Macrofauna invertebrada edáfica em cultivo de mandioca sob sistemas de cobertura do solo Edaphic invertebrate macrofauna in cassava cultivation under vegetable cover crops

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Rogério Ferreira da Silva

2007-06-01

Full Text Available O objetivo deste trabalho foi avaliar o efeito do cultivo da mandioca em diferentes sistemas de cobertura do solo na densidade e diversidade da comunidade da macrofauna de invertebrados edáfica. O trabalho foi conduzido no Município de Glória de Dourados, MS, num Argissolo Vermelho, sob sistema convencional (SC, plantio direto sobre palhada de mucuna (PDMu, sorgo (PDSo e milheto (PDMi, além de sistema com vegetação nativa (VN, como referencial para comparação. As avaliações foram realizadas em quatro épocas distintas: abril/2003 (antes do plantio, novembro/2003 (6 meses após o plantio, abril/2004 (11 meses após o plantio e novembro/2004 (18 meses após o plantio. Houve efeito da interação entre os sistemas avaliados e as épocas de amostragens sobre a densidade, riqueza e diversidade da macrofauna invertebrada do solo. Entre os grupos da macrofauna invertebrada do solo, cupins, formigas e coleópteros (imaturo e adulto foram predominantes no ambiente estudado. O uso de plantas de cobertura no pré-cultivo de mandioca no sistema plantio direto proporcionou condições para a recomposição da comunidade de macrofauna invertebrada do solo, o que indica que as espécies utilizadas, mucuna, sorgo e milheto, representam alternativas promissoras para melhor manejo dessa cultura.The objective of this work was to evaluate the effect of cassava cultivation under different vegetable cover crops according to the density and diversity of soil invertebrate macrofauna. Field experiment was carried out at Glória de Dourados, Mato Grosso do Sul State, Brazil, on an Oxisol, under conventional drilling (SC, no-tillage system under Stizolobium cinereum (PDMu, Sorghum bicolor (PDSo and Pennisetum glaucum (PDMi mulching, with comparison of native vegetation system (VN. Evaluations were performed in April/2003 (before sowing, November/2003 (6 months after sowing, April/2004 (11 months after sowing and November/2004 (18 months after sowing. Significant

Spatial Structure of Soil Macrofauna Diversity and Tree Canopy in Riparian Forest of Maroon River

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Ehsan Sayad

2017-02-01

Full Text Available Introduction: Sustainability and maintenance of riparian vegetation or restoring of degraded sites is critical to sustain inherent ecosystem function and values. Description of patterns in species assemblages and diversity is an essential step before generating hypotheses in functional ecology. If we want to have information about ecosystem function, soil biodiversity is best considered by focusing on the groups of soil organisms that play major roles in ecosystem functioning when exploring links with provision of ecosystem services. Information about the spatial pattern of soil biodiversity at the regional scale is limited though required, e.g. for understanding regional scale effects of biodiversity on ecosystem processes. The practical consequences of these findings are useful for sustainable management of soils and in monitoring soil quality. Soil macrofauna play significant, but largely ignored roles in the delivery of ecosystem services by soils at plot and landscape scales. One main reason responsible for the absence of information about biodiversity at regional scale is the lack of adequate methods for sampling and analyzing data at this dimension. An adequate approach for the analysis of spatial patterns is a transect study in which samples are taken in a certain order and with a certain distance between samples. Geostatistics provide descriptive tools such as variogram to characterize the spatial pattern of continuous and categorical soil attributes. This method allows assessment of consistency of spatial patterns as well as the scale at which they are expressed. This study was conducted to analyze spatial patterns of soil macrofauna in relation to tree canopy in the riparian forest landscape of Maroon. Materilas and Methods: The study was carried out in the Maroon riparian forest of the southeasternIran (30o 38/- 30 o 39/ N and 50 o 9/- 50 o 10/ E. The climate of the study area is semi-arid. Average yearly rainfall is about 350.04 mm

Effects of plant cover on the macrofauna of Spartina marshes in northern Brazil

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Cesar França Braga

2009-12-01

Full Text Available Data on macrofauna density and diversity, and the height and density of Spartina brasiliensis, were obtained from salt marsh beds of a tropical estuary in northern Brazil. Sampling was carried out at four distinct times of the year, during the wet and dry seasons and in the transition periods between these. Sampling was also carried out in salt marshes of three size classes, small, medium and large. Variables were analyzed in relation to time of year and salt marsh size class. Overall, 46 taxa were found, with polychaetes, isopods and the gastropod Neritina virginea dominating the fauna. Macrofauna density and diversity were positively correlated with culm density, indicating a possible role in protection from predation. All the three variables were higher during the transitional periods between the wet and dry seasons and seasonal changes in rainfall, salinity and light availability may influence mortality, food availability and settlement of the macrofauna. There was no effect of salt marsh size on either the macrofauna or the vegetation.Dados sobre a densidade e diversidade da macrofauna em relação à altura e densidade de Spartina brasiliensis foram obtidos em bancos de marismas em um estuário tropical no norte do Brasil. A amostragem foi realizada quatro vezes durante um ano, nas estações chuvosa, seca e nos períodos de transição entre estas. A amostragem foi realizada em marismas de três classes de tamanho: pequeno, médio e grande. As variáveis foram analisadas em relação às estações do ano e das classes de tamanho das marismas. Um total de 46 táxons foram encontrados, com os poliquetos, isopodos e o gastropódo Neritina virginea dominando a fauna, resultados similares a estudos realizados em marismas no sul do Brasil. A densidade e a diversidade da macrofauna foram correlacionadas positivamente com a densidade de colmos da vegetação, indicando um possível papel da vegetação em proteção contra predação. Todas as

Stimulation of microbial nitrogen cycling in aquatic ecosystems by benthic macrofauna: mechanisms and environmental implications

DEFF Research Database (Denmark)

Stief, P.

2013-01-01

(mainly nitrate and ammonium) and the emission of the greenhouse gas nitrous oxide are evaluated. Published data indicate that ecosystem engineering by sediment-burrowing macrofauna stimulates benthic nitrification and denitrification, which together allows fixed nitrogen removal. However, the release...... enhance nitrous oxide emission from shallow aquatic ecosystems. The beneficial effect of benthic macrofauna on fixed nitrogen removal through coupled nitrification-denitrification can thus be offset by the concurrent release of (i) ammonium that stimulates aquatic primary production and (ii) nitrous oxide...... of ammonium from sediments is enhanced more strongly than the sedimentary uptake of nitrate. Ecosystem engineering by reef-building macrofauna increases nitrogen retention and ammonium concentrations in shallow aquatic ecosystems, but allows organic nitrogen removal through harvesting. Grazing by macrofauna...

Soil macrofauna in cover crops of figs grown under organic management Macrofauna edáfica sob coberturas do solo no cultivo de figo sob manejo orgânico

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Analy de Oliveira Merlim

2005-01-01

Full Text Available Soil fauna plays an important role in organic management through their effects on soil organic decomposition, nutrient mineralization, and amelioration of the soil's physical properties. This work evaluates the density and diversity of the soil macrofauna under types of cover plants in areas cultivated with Ficus carica L. under organic management. The soil macrofauna was collected in 0.25 × 0.25 m areas, down to a soil depth of 0.3 m, and at the surface layer. The treatments consisted of bahiagrass living mulch (Paspalum notatum, siratro living mulch (Macroptilium atropurpureum, and bahiagrass mulch. The highest macrofauna density and the lowest diversity were observed in bahiagrass, of which 80% were represented by ants, thus characterizing the soil under this cover crop as showing the lowest functional diversity and quality.A fauna do solo tem papel importante em sistemas orgânicos, através dos seus efeitos na decomposição da matéria orgânica, mineralização de nutrientes e condicionamento físico do solo. Este trabalho avaliou a densidade e a diversidade da macrofauna edáfica sob tipos de cobertura do solo em áreas cultivadas com Ficus carica L. sob manejo orgânico do solo. A macrofauna foi coletada em áreas de 0,25 × 0,25 m e amostraram-se as camadas de material vegetal e solo até a profundidade de 0,3 m, nos meses de março e setembro de 2001. Os tratamentos constaram de cobertura viva com grama batatais (Paspalum notatum, cobertura viva de siratro (Macroptilium atropurpureum e cobertura morta formada por palha de grama batatais. A mais alta densidade da macrofauna e a mais baixa diversidade foi observada em grama batatais, sendo mais de 80% dessa fauna de formigas, o que caracteriza o solo sob influência desta cobertura como o de mais baixa diversidade funcional e qualidade, comparado às outras coberturas.

Kunstmatige substraten als standaard-monstermethode voor macrofauna in sloten. Een onderzoek in de Volgermeerpolder

NARCIS (Netherlands)

Brinkkemper, Otto

1986-01-01

This report, deals with a research about the applicability of artificial substrates as a standard sampling-method for macrofauna. Macrofauna is considered as the macroscopic invertebrate fauna in aquatic ecosystems. The artificial substrates, open steel constructions filled with roofing-tiles, were

Soil macrofauna in wooded pasture with legume trees

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Lusimar Lamarte Gonzaga Galindo da Silva

2015-07-01

Full Text Available Grasslands afforestation aims at adding different soil uses in a way they become profitable for their owners. As such handling aims at minimizing impacts, the current study had as its goal the use of soil macrofauna in order to evaluate legume afforestation effects on the soil, regardless the depth. Thus, nitrogen fixing species were inserted onto grassland areas and the macrofauna collection was performed 6 years after their planting in the 0-10cm, 10-20cm and 20.30cm layers, in winter and summer. Leguminous influence was different between depths and times of the year. It mostly favors communities under "Mimosa" Genus treetops. Besides, the effects from climatic seasonal variations on invertebrates were mitigated by the implementation of such legume trees

Antifouling Compounds from Marine Macroalgae.

Science.gov (United States)

Dahms, Hans Uwe; Dobretsov, Sergey

2017-08-28

Marine macroalgae produce a wide variety of biologically-active metabolites that have been developed into commercial products, such as antibiotics, immunosuppressive, anti-inflammatory, cytotoxic agents, and cosmetic products. Many marine algae remain clean over longer periods of time, suggesting their strong antifouling potential. Isolation of biogenic compounds and the determination of their structure could provide leads for the development of environmentally-friendly antifouling paints. Isolated substances with potent antifouling activity belong to fatty acids, lipopeptides, amides, alkaloids, lactones, steroids, terpenoids, and pyrroles. It is unclear as yet to what extent symbiotic microorganisms are involved in the synthesis of these compounds. Algal secondary metabolites have the potential to be produced commercially using genetic and metabolic engineering techniques. This review provides an overview of publications from 2010 to February 2017 about antifouling activity of green, brown, and red algae. Some researchers were focusing on antifouling compounds of brown macroalgae, while metabolites of green algae received less attention. Several studies tested antifouling activity against bacteria, microalgae and invertebrates, but in only a few studies was the quorum sensing inhibitory activity of marine macroalgae tested. Rarely, antifouling compounds from macroalgae were isolated and tested in an ecologically-relevant way.

Changes in diversity, biomass and abundance of soil macrofauna, Parrotio-Carpinetum forest at organic and semi-organic horizons

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Masomeh Izadi

2016-07-01

Full Text Available Present study evaluates diversity, abundance and biomass of soil macrofauna in organic and semi-organic horizons in Parrotia persica-Carpinus betulus forest in Shast kola area. Totally 70 sample points were randomly selected from organic and semi-organic horizons then sampling was done by a rectangle 100 cm2 area. Soil macrofauna were separated from soil samples by hand sorting and using Berlese funnel then dried at 60°C for 72h and weighted in 0.001 gr. With using taxonomic classification key, thirteen macrofauna orders were identified. Most of abundance of soil macrofauna in both soil horizons were allocated to Millipedes order. Changes in diversity, abundance and biomass of macrofauna in both soil horizons were calculated. The results showed Shannon diversity index, Simpson evenness and Margalef richness indices in semi-organic horizon were more than organic horizon. Abundance and biomass of macrofauna in semi-organic horizon were more than organic horizon.

Diversity and Spatial-Temporal Distribution of Soil Macrofauna Communities Along Elevation in the Changbai Mountain, China.

Science.gov (United States)

Yin, Xiuqin; Qiu, Lili; Jiang, Yunfeng; Wang, Yeqiao

2017-06-01

The understanding of patterns of vertical variation and diversity of flora and fauna along elevational change has been well established over the past century. However, it is unclear whether there is an elevational distribution pattern for soil fauna. This study revealed the diversity and spatial-temporal distribution of soil macrofauna communities in different vegetation zones from forest to alpine tundra along elevation of the Changbai Mountain, China. The abundance, richness, and Shannon-Wiener diversity index of soil macrofauna communities were compared in four distinguished vegetation zones including the coniferous and broadleaved mixed forest zone, the coniferous forest zone, the subalpine dwarf birch (Betula ermanii) forest zone, and the alpine tundra zone. Soil macrofauna were extracted in May, July, and September of 2009. In each season, the abundance and richness of the soil macrofauna decreased with the ascending elevation. The Shannon-Wiener diversity indices of the soil macrofauna were higher in the vegetation zones of lower elevation than of higher elevation. Significant differences were observed in the abundance, richness, and Shannon-Wiener diversity index for the studied vegetation zones. Soil macrofauna congregated mainly to the litter layer in the low-elevation areas and in the 0-5 cm soil layer of the higher elevation areas. The results emphasized that the diversity of soil macrofauna communities decreased as the elevation increased and possess the distinct characteristics of zonation in the mountain ecosystem. The diversity and distribution of soil macrofauna communities were influenced by mean annual precipitation, altitude, annual radiation quantity, and mean annual temperature. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Dynamic of epigeous macrofauna under organic soil management in the Brazilian semi-arid regionDinâmica da macrofauna epígea sob manejo orgânico do solo no semi-árido brasileiro

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Márcio Sampaio Pimentel

2012-04-01

Full Text Available Soil macrofauna is responsible for soil fertility through cycling of nutrients, tillage and fragmentation of organic matter, as well as through the association between groups of fauna with conserved and/or degraded pedoenvironments. Nevertheless, under the conditions of the Brazilian semi-arid region, there is little information about this resource. The objective of this study was to evaluate the epigeous macrofauna in successive cropping using previous green manure and subsequent planting of melon (Cucumis melo L. in Juazeiro county, Bahia, Brazil. Sampling dates were undertaken in November 2007 and February, April and July 2008, using traps containing 4 % formaldehyde for seven days in plots of 64 m2. Results obtained indicate that there is no difference among the treatments with mixed cover crops, and epigeous macrofauna is influenced by the time of collection. Diversity and uniformity are inversely correlated with total density of epigeous macrofauna. Diversification of plant species favors the increase of diversity and uniformity of epigeous macrofauna. Formicidae, followed by Isopoda, Coleoptera and Oligochaeta are the groups of fauna most numerous in the areas. A macrofauna do solo é responsável pela melhoria da fertilidade do solo através da ciclagem de nutrientes, revolvimento e fragmentação da matéria orgânica, como também, pela associação entre grupos de fauna com pedoambientes conservados e/ou degradados. No entanto, nas condições de semi-árido brasileiro pouca informação se tem a respeito deste recurso. Neste sentido, na região do sub-médio do Rio São Francisco, pólo de desenvolvimento da agricultura irrigada objetivou-se avaliar a macrofauna epígea em sucessão cultural utilizando prévia adubação verde e subseqüente plantio de melão (Cucumis melo L.. As coletas foram realizadas em novembro de 2007 e fevereiro, abril e julho de 2008 no município de Juazeiro, BA, utilizando armadilhas contendo formol 4

MACROFAUNA DIVERSITY AND ABUNDANCE ACROSS DIFFERENT LAND USE SYSTEMS IN EMBU, KENYA

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Fred Ayuke

2009-10-01

Full Text Available This paper presents data on diversity and abundance of soil macrofauna of various land use systems in Embu, Kenya (natural forest, plantation forest, fallow, coffee, tea, napier, and maize. Each was sampled for macrofauna using three sampling methods (monolith, transect and pitfall traps. Thirty four (34 genera/species of soil macrofauna were recorded, the highest number (27 being observed in napier. Majority of these genera/species being Coleoptera. Rényi diversity profile indicated that in terms of species richness (α at 0, maize the richest of all the land use systems, but plantation forest the least. It was however not possible to clearly order or rank the land use system in terms of diversity because of the bias of each of the two diversity indices as indicated by the numerous crossings observed for the diversity profiles/curves. Shannon index of diversity (α = 1 indicated that coffee was the most diverse of the land use systems followed by plantation forest > natural forest > napier > maize > tea, while fallow/pasture was the least diverse (Figure 1. On the other hand, Simpson’s diversity (α = 2 indicated that plantation forest was the most diverse followed by fallowed by coffee > natural forest > napier > maize >tea > fallow/pasture. Rényi evenness profile indicated that the plantation forest was most even in terms of species distribution followed by natural forest and coffee > napier > tea > maize but least even in the fallow/pasture. Hymenoptera were most abundant of the macrofauna groups constituting about 45% of the total followed by Isoptera (39%, Coleoptera (6%, Oligochaeta (5%, Orthoptera (3% and Arenae (2%. The other groups that comprised of Hemiptera, Diptera, Phasmidae and Blattelidae each constituted coffee (1170 > natural forest (1110 > tea (755, but lowest in plantation forest (309, although analysis of variance indicated no significant variation among the land use systems. This study however

Development of Radiation Breeding Technology of Macroalgae

Energy Technology Data Exchange (ETDEWEB)

Choi, Jongil; Park, J. H.; Song, B. S.; Kim, J. K.; Kim, J. H.; Lee, H. J.; Yang, H. Y.

2013-01-15

Macroalgae has been utilized as food material from long time ago, and recently newly recognized as functional materials and the source of bio-fuel. But, the study on the macroalgae is just beginning and the study on radiation effect and radiation breeding technology was not reported. In this study, the effect of radiation on the macroalgae Porphyra was investigated for the development of new mutant strains. Prphyra was successively cultivated in the laboratory chamber with optimized growth condition. Also, the radiation sensitivity of Porphyra was determined. To develop the mutant strain, irradiated Porphyra strains were screened for better growth and higher resistance against oxidative stress. The selected Porphyra was further cultivated in ocean site. Also, several genes from mutant Porphyra was heterologous expressed and studied for its dunctionality. This results can provide mutation technology of macroalgae and further contribute in the activation of fishery industry and national health enhancement.

Development of Radiation Breeding Technology of Macroalgae

International Nuclear Information System (INIS)

Choi, Jongil; Park, J. H.; Song, B. S.; Kim, J. K.; Kim, J. H.; Lee, H. J.; Yang, H. Y.

2013-01-01

Macroalgae has been utilized as food material from long time ago, and recently newly recognized as functional materials and the source of bio-fuel. But, the study on the macroalgae is just beginning and the study on radiation effect and radiation breeding technology was not reported. In this study, the effect of radiation on the macroalgae Porphyra was investigated for the development of new mutant strains. Prphyra was successively cultivated in the laboratory chamber with optimized growth condition. Also, the radiation sensitivity of Porphyra was determined. To develop the mutant strain, irradiated Porphyra strains were screened for better growth and higher resistance against oxidative stress. The selected Porphyra was further cultivated in ocean site. Also, several genes from mutant Porphyra was heterologous expressed and studied for its dunctionality. This results can provide mutation technology of macroalgae and further contribute in the activation of fishery industry and national health enhancement

Loss of soil (macro)fauna due to the expansion of Brazilian sugarcane acreage.

Science.gov (United States)

Franco, André L C; Bartz, Marie L C; Cherubin, Maurício R; Baretta, Dilmar; Cerri, Carlos E P; Feigl, Brigitte J; Wall, Diana H; Davies, Christian A; Cerri, Carlos C

2016-09-01

Land use changes (LUC) from pasture to sugarcane (Saccharum spp.) crop are expected to add 6.4Mha of new sugarcane land by 2021 in the Brazilian Cerrado and Atlantic Forest biomes. We assessed the effects of these LUC on the abundance and community structure of animals that inhabit soils belowground through a field survey using chronosequences of land uses comprising native vegetation, pasture, and sugarcane along a 1000-km-long transect across these two major tropical biomes in Brazil. Macrofauna community composition differed among land uses. While most groups were associated with samples taken in native vegetation, high abundance of termites and earthworms appeared associated with pasture soils. Linear mixed effects analysis showed that LUC affected total abundance (X(2)(1)=6.79, p=0.03) and taxa richness (X(2)(1)=6.08, p=0.04) of soil macrofauna. Abundance increased from 411±70individualsm(-2) in native vegetation to 1111±202individualsm(-2) in pasture, but decreased sharply to 106±24individualsm(-2) in sugarcane soils. Diversity decreased 24% from native vegetation to pasture, and 39% from pasture to sugarcane. Thus, a reduction of ~90% in soil macrofauna abundance, besides a loss of ~40% in the diversity of macrofauna groups, can be expected when sugarcane crops replace pasture in Brazilian tropical soils. In general, higher abundances of major macrofauna groups (ants, coleopterans, earthworms, and termites) were associated with higher acidity and low contents of macronutrients and organic matter in soil. This study draws attention for a significant biodiversity loss belowground due to tropical LUC in sugarcane expansion areas. Given that many groups of soil macrofauna are recognized as key mediators of ecosystem processes such as soil aggregation, nutrients cycling and soil carbon storage, our results warrant further efforts to understand the impacts of altering belowground biodiversity and composition on soil functioning and agriculture performance

Diversity Patterns of Benthic Macrofauna Caused by Marine Fish Farming

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Arnaldo Marín

2011-04-01

Full Text Available This paper reviews the patterns observed in the diversity and structure of the macrofauna benthic community under the influence of fish farming. First, we explain the effects of organic enrichment on the sediment and the consequences for the inhabiting communities. We describe the diversity trends in spatial and temporal gradients affected by fish farming and compare them with those described by the Pearson and Rosenberg model. We found that in general terms, the trends of diversity and other community parameters followed the Pearson and Rosenberg model but they can vary to some extent due to sediment local characteristics or to secondary disturbances. We also show the different mechanisms by which wild fish can affect macrofauna diversity patterns under fish farming influence. In addition, we comment the importance of the macrofauna diversity in the ecosystem functions and propose some guidelines to measure functional diversity related to relevant processes at ecosystem level. We propose more research efforts in the main topics commented in this review to improve management strategies to guarantee a good status of the diversity and ecosystem functioning of sediments influenced by fish farming.

CHANGES IN SOIL MACROFAUNA IN AGROECOSYSTEMS DERIVED FROM LOW DECIDUOUS TROPICAL FOREST ON LEPTOSOLS FROM KARSTIC ZONES

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Francisco Bautista

2009-02-01

Full Text Available In Yucatan Mexico the method of slash and burn is used for the establishment of pastures. Pastures are developed for 15 to 20 years, no more because weed control is too expensive. The impact of these practices on soil macrofauna had not been evaluated. Because of its wide distribution, diverse habits and high sensitivity to disturbance, soil macrofauna is considered a valuable indicator of soil health, allowing monitoring of soil sustainability. We studied soil macrofauna communities in low deciduous tropical forest and four livestock agroecosystems with increasing management-derived disturbance including a silvopastoral system, Taiwan grass (Cynodon nlemfuensis and Star grass (Pennisetum purpureum pastures in order to describe community structure across systems, and evaluate disturbance sensitivity of taxonomical groups to detect taxa with potential use as biological indicators of soil health or degradation. Pitfall traps were used at each of the systems to sample soil macrofauna. We estimate their taxonomical abundance, biomass, richness (order, morphospecies, diversity, dominance and response to disturbance on agroecosystems and the forest. We found 133 macrofauna morphospecies of 15 taxa. Groups with more individuals were: Hymenoptera (64.97%, Coleoptera (22.68%, and Orthoptera (3.91%.  Agroecosystem of two-year old Taiwan-grass pasture (TP2 had the highest macrofauna abundances, biomass and richness, low diversity, and a non-homogeneous distribution of individuals among species; in contrast, silvopastoral system (SP, had low abundance and biomass, the lowest specific richness, high diversity and a homogeneous distribution of individuals among species. The discriminant analysis revealed that the agroecosystems and the forest serve to predict the macrofauna communities, since they have particular or typical soil macrofauna. The cases (sampled points with a correct assignation by agroecosystems were: Forest (70%, Sivopastoral system (70

Platform construction of molecular breeding for utilization of brown macroalgae.

Science.gov (United States)

Takagi, Toshiyuki; Kuroda, Kouichi; Ueda, Mitsuyoshi

2018-01-01

Brown macroalgae are characterized by a large size and high productivity without requiring arable land, fresh water, and fertilizer. Furthermore, since brown macroalgae contain little or no lignin, simple biorefinery processing can efficiently produce sugars from this material. Therefore, brown macroalgae have attracted attention as an alternative feedstock for bioethanol production. However, the utilization of biotechnologies previously developed for terrestrial biomass processing results in difficulties in the bioconversion of brown macroalgae. Recently, several studies have developed biotechnologies for using major carbohydrates of brown macroalgae, such as laminarin, mannitol, and alginate. This review focuses on these fermentation biotechnologies using natural or engineered microorganisms. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Meiofaunal assemblages associated with native and non-indigenous macroalgae

Science.gov (United States)

Veiga, Puri; Sousa-Pinto, Isabel; Rubal, Marcos

2016-07-01

Meiofauna is a useful tool to detect effects of different disturbances; however, its relevance in the frame of biological invasions has been almost fully neglected. Meiofaunal assemblages associated with the invasive macroalga Sargassum muticum were studied and compared with those associated with two native macroalgae (Bifurcaria bifurcata and Chondrus crispus). We used a linear mixed model to determine the influence of habitat size (i.e. macroalgal biomass) in shaping meiofaunal assemblages. Results showed that habitat size (i.e. macroalgal biomass) shaped meiofaunal assemblages influencing its abundance, richness and structure. However, the identity of macroalga (i.e. species) appears also to play a significant role, particularly the differences of complexity among the studied species may shape their meiofaunal assemblages. Finally, the invasive macroalga appears to influence positively species richness. Our results highlight the need of including different faunal components to achieve a comprehensive knowledge on effects of invasive macroalgae and that meiofaunal assemblages may be a valuable tool to examine them.

Macrofauna Settlement on Pearl Oyster Collectors in Kenya ...

African Journals Online (AJOL)

Key words: Pearl oysters, seed collection, macrofauna, bivalves, settlement, monsoon seasons,. Kenya .... have shown that pearl oyster settlement is higher within calm ...... collectors in the Timor Sea, Northern Australia. J. Shellfish ... systems. Aquaculture, 189: 375-388. Urban, H.J. (2000b): Culture potential of the pearl.

Tracking macroalgae introductions in North Atlantic oceanic islands

Science.gov (United States)

Micael, Joana; Parente, Manuela I.; Costa, Ana C.

2014-06-01

The Azores archipelago was selected as a case study since there are few studies on macroalgae introduction in oceanic islands. While at a global scale, around 3 % of macroalgae are considered non-indigenous; in the remote oceanic islands of the Azores, over 6 % of the marine algal flora is non-indigenous. The taxa distribution pattern of non-indigenous species in the Azores is significantly different from the distribution pattern in the globe. The most representative group was Rhodophyta species, being 84 % of the total non-indigenous macroalgae, mainly introduced via maritime traffic. This study highlights the vulnerability of remote islands to the introduction of macroalgae and the need to develop further studies on other archipelagos to understand whether the observed vulnerability is generally characteristic of oceanic islands. The development of local monitoring and mitigation programs and the necessity of regulatory and preventive measures for the maritime traffic vector are strongly suggested.

Processing of 13C-labelled phytoplankton in a fine-grained sandy-shelf sediment (North Sea): relative importance of different macrofauna species

DEFF Research Database (Denmark)

Kamp, Anja; Witte, Ursula

2005-01-01

by additional laboratory experiments on the role of the dominant macrofauna organism, the bivalve Fabulina fabula (Bivalvia: Tellinidae), for particulate organic matter subduction to deeper sediment layers. The specific uptake of algal 13C by macrofauna organisms was visible after 12 h and constantly increased...... carbon processing. Predatory macrofauna organisms like Nephtys spp. (Polychaeta: Nephtyidae) also quickly became labelled. The rapid subduction of fresh organic matter by F. fabula down to ca. 4 to 7 cm sediment depth could be demonstrated, and it is suggested that entrainment by macrofauna in this fine...

Substantial role of macroalgae in marine carbon sequestration

KAUST Repository

Krause-Jensen, Dorte; Duarte, Carlos M.

2016-01-01

Vegetated coastal habitats have been identified as important carbon sinks. In contrast to angiosperm-based habitats such as seagrass meadows, salt marshes and mangroves, marine macroalgae have largely been excluded from discussions of marine carbon sinks. Macroalgae are the dominant primary producers in the coastal zone, but they typically do not grow in habitats that are considered to accumulate large stocks of organic carbon. However, the presence of macroalgal carbon in the deep sea and sediments, where it is effectively sequestered from the atmosphere, has been reported. A synthesis of these data suggests that macroalgae could represent an important source of the carbon sequestered in marine sediments and the deep ocean. We propose two main modes for the transport of macroalgae to the deep ocean and sediments: macroalgal material drifting through submarine canyons, and the sinking of negatively buoyant macroalgal detritus. A rough estimate suggests that macroalgae could sequester about 173 TgC yr â '1 (with a range of 61-268 TgC yr â '1) globally. About 90% of this sequestration occurs through export to the deep sea, and the rest through burial in coastal sediments. This estimate exceeds that for carbon sequestered in angiosperm-based coastal habitats.

Substantial role of macroalgae in marine carbon sequestration

KAUST Repository

Krause-Jensen, Dorte

2016-09-12

Vegetated coastal habitats have been identified as important carbon sinks. In contrast to angiosperm-based habitats such as seagrass meadows, salt marshes and mangroves, marine macroalgae have largely been excluded from discussions of marine carbon sinks. Macroalgae are the dominant primary producers in the coastal zone, but they typically do not grow in habitats that are considered to accumulate large stocks of organic carbon. However, the presence of macroalgal carbon in the deep sea and sediments, where it is effectively sequestered from the atmosphere, has been reported. A synthesis of these data suggests that macroalgae could represent an important source of the carbon sequestered in marine sediments and the deep ocean. We propose two main modes for the transport of macroalgae to the deep ocean and sediments: macroalgal material drifting through submarine canyons, and the sinking of negatively buoyant macroalgal detritus. A rough estimate suggests that macroalgae could sequester about 173 TgC yr â \\'1 (with a range of 61-268 TgC yr â \\'1) globally. About 90% of this sequestration occurs through export to the deep sea, and the rest through burial in coastal sediments. This estimate exceeds that for carbon sequestered in angiosperm-based coastal habitats.

Macroalgae - Production and Biorefining in Denmark

DEFF Research Database (Denmark)

Seghetta, Michele; Hou, Xiaoru; Bastianoni, Simone

Macroalgae is a key biomass for the development of circular economy. This study analyzes the environmental sustainability of a macroalgae production and conversion system in Denmark. A brown algae model based on Laminaria digitata and Saccharina latissima is utilized as feedstock for a biorefinery...... system which produces bioethanol, fish feed and liquid fertilizers. A Life Cycle Assessment was conducted from cradle to grave; i.e. from cultivation and harvest of biomass, to the use phase of the products....

Soil macrofauna under integrated crop-livestock systems in a Brazilian Cerrado Ferralsol Macrofauna edáfica em sistemas de integração lavoura-pecuária num Latossolo Vermelho do Cerrado

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Robélio Leandro Marchão

2009-08-01

Full Text Available The objective of this work was to assess the effects of integrated crop-livestock systems, associated with two tillage and two fertilization regimes, on the abundance and diversity of the soil macrofauna. Four different management systems were studied: continuous pasture (mixed grass; continuous crop; two crop-livestock rotations (crop/pasture and pasture/crop; and native Cerrado as a control. Macrofauna was sampled using a modified Tropical Soil Biology and Fertility method, and all individuals were counted and identified at the morphospecies level for each plot. A total of 194 morphospecies were found, distributed among 30 groups, and the most representative in decreasing order of density were: Isoptera, Coleoptera larvae, Formicidae, Oligochaeta, Coleoptera adult, Diplopoda, Hemiptera, Diptera larvae, Arachnida, Chilopoda, Lepidoptera, Gasteropoda, Blattodea and Orthoptera. Soil management systems and tillage regimes affected the structure of soil macrofauna, and integrated crop-livestock systems, associated with no-tillage, especially with grass/legume species associations, had more favorable conditions for the development of "soil engineers" compared with continuous pasture or arable crops. Soil macrofauna density and diversity, assessed at morphospecies level, are effective data to measure the impact of land use in Cerrado soils.O objetivo deste trabalho foi avaliar os efeitos de sistemas de integração lavoura-pecuária, associados a dois tipos de preparo e de fertilização do solo, sobre a abundância e a diversidade da macrofauna edáfica. Quatro sistemas de manejo foram estudados: pastagem contínua de gramíneas; lavoura contínua de culturas anuais; dois sistemas integrados lavoura-pecuária (lavoura/pastagem e pastagem/lavoura; e Cerrado nativo (controle. A macrofauna foi avaliada pelo método "Tropical Soil Biology and Fertility" modificado e todos os indivíduos coletados nas parcelas foram contados e identificados ao nível de

Quantification of the macrofauna in a vertisol under different systems from handling in the Cauca Valley, Colombia

International Nuclear Information System (INIS)

Marin, Elida P; Feijoo, A; Pena, J de J

2001-01-01

Using the tropical soil biology and fertility (TSBF) methodology the biodiversity, the density and biomass of macrofauna was evaluated in a vertisol soil under four tillage systems and in a cocoa plantation with an undisturbed for more than 20 years. Soil under cocoa showed the highest values of biodiversity (47 u.t.) while mulch tiller treatment showed the highest density (122 ind. 0.062 m 2 ) and direct seeding the highest value of biomass (5.44 g. 0.062 m 2 ). Ants, Myriapods and earthworms exhibited greater level of population density (41 +/- 28; 15 +/- 8 and 8 +/- 5 ind. 0.062 m 2 , respectively) while the greatest contribution to biomass was made by earthworms and coleoptera population with 2.3 +/- 1.7 and 0.27 +/- 0.32 g. 0.062 m 2 . Soil under cocoa plantation and direct seeding presented the highest proportion of macrofauna at the top 5 cm (58.2 and 51.1 % respectively) while treatments with soil disturbance as mulch tiller, disk plowing and chisel plow the distribution of macrofauna was between 5 to 20 cm depth (55.8,53.7 and 46.2 %). this study evidenced the sensibility of the soil's macrofauna to different tillage systems. Macrofauna quantifying could be used to evaluate soil conditions under different management methods

Characterisation of estuarine intertidal macroalgae by laser-induced fluorescence

DEFF Research Database (Denmark)

Gameiro, Carla; Utkin, Andrei B.; Sousa Dias Cartaxana, Paulo Jorge

2015-01-01

The article reports the application of laser-induced fluorescence (LIF) for the assessment of macroalgae communities of estuarine intertidal areas. The method was applied for the characterisation of fifteen intertidal macroalgae species of the Tagus estuary, Portugal, and adjacent coastal area...... spectra were determined by differences in the main fluorescing pigments: phycoerythrin, phycocyanin and chlorophyll a (Chl a). In the green and brown macroalgae groups, the relative significance of the two emission maxima seems to be related to the thickness of the photosynthetic layer. In thick...... macroalgae, like Codium tomentosum or Fucus vesiculosus, the contribution of the far-red emission fluorescence peak was more significant, most probably due to re-absorption of the emitted red Chl a fluorescence within the dense photosynthetic layer. Similarly, an increase in the number of layers of the thin...

Macrofauna edáfica e sua interação com atributos químicos e físicos do solo sob diferentes sistemas de manejo = Edaphic macrofauna and its interaction with the soil's chemical and physical properties under different management systems

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Marlene Estevão Marchetti

2007-01-01

Full Text Available O presente trabalho teve o objetivo de avaliar a macrofauna edáfica sob diferentes sistemas de uso do solo. Avaliaram-se os sistemas: plantio convencional, plantio direto, pastagem contínua, integração lavoura-pecuária, eucalipto e vegetação nativa. As amostragens foram realizadas em cinco pontos em cada sistema, ao longo de um transecto.Os organismos foram extraídos manualmente e identificados em nível de grandes grupos taxonômicos. A vegetação nativa apresentou uma maior riqueza de grupos da comunidade da macrofauna edáfica em comparação aos sistemas conduzidos em monocultivos e/ou com alta intensidade de revolvimento do solo. Entre os sistemas cultivados, a maior densidade de organismos da macrofauna edáfica ocorreu nos sistemas sob integração lavoura/pecuária e em pastagem cultivada continuamente. A densidade total de indivíduos e a riqueza de grupos da macrofauna não foram influenciadas pelos atributos físicos do solo. Em relaçãoaos atributos químicos, apenas a riqueza de grupos se correlacionou com algumas propriedades.This work aimed to evaluate edaphic macrofauna under different soil use systems. Two systems were evaluated: conventional system, no-till, continuous grazing, crop-cattle integration, eucalyptus andnative vegetation. Sampling was carried out in five points at one transect per system. Organisms were manually extracted and identified to the level of broad taxonomic groups. Native vegetation did show the highest variety of edaphic macrofauna groups when compared to monocultures and/or high intensity of soil tillage. Among cropped systems, the highest density of edaphic macrofauna organisms was observed in crop-cattle integration and continuous grazing systems. The total density of individuals and the macrofauna group richness were not influenced by soil physical attributes. Regarding to chemical attributes, only the group richness was correlated to some of such proprieties.

Macrofauna edáfica asociada con sistemas agroforestales en la Amazonía Colombiana

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Juan Carlos Suárez Salazar

2015-07-01

Full Text Available La densidad, riqueza y diversidad de la macrofauna edáfica son afectadas, entre otros factores, por la configuración de los agroecosistemas y la estacionalidad de la precipitación. Con el fin de evaluar estos efectos en mayo y noviembre de 2011, correspondientes a épocas de máxima y mínima precipitación, respectivamente, se realizaron estudios sobre la composición de la macrofauna edáfica asociada con los arreglos agroforestales ubicados en el Centro de Investigaciones Macagual Cesar Augusto Estrada González, Amazonia, Caquetá, Colombia. El experimento se dispuso en un diseño completo al azar bifactorial con cuatro tratamientos (arreglos agroforestales: AB = abarco - Cariniana pyriformis Miers; CH = caucho Hevea brasiliensis (Willd. ex A. Juss. Müll. Arg. ; CP = caucho-parica Schizolobium amazonicum Huber; UV = uvito Genipa Americana L. y dos épocas (máxima y mínima precipitación, y cuatro repeticiones en parcelas divididas. Para explorar las relaciones entre los órdenes de macrofauna, se realizó un análisis de componentes principales y se evalúo el efecto de los arreglos agroforestales con una prueba de Monte Carlo. Los resultados mostraron que la densidad de la macrofauna fue mayor en el periodo de máxima precipitación (1129 individuos en comparación con el de mínima (598 individuos. Los arreglos agroforestales influyen sobre la presencia o ausencia de algunos grupos taxonómicos (P < 0.05 como Homoptera (Insecta y Raphidioptera (Insecta; además los UV y AB pueden favorecer a la macrofauna del estrés por sequía

Characterization of sediment trapped by macroalgae on a Hawaiian reef flat

Science.gov (United States)

Stamski, Rebecca E.; Field, Michael E.

2006-01-01

Reef researchers studying community shifts in the balance between corals and fleshy macroalgae have noted that algae are often covered with sediment. This study characterizes sediment trapping by macroalgae within a Hawaiian reef habitat and constrains the controls on this process. Sediment-laden macroalgae were sampled and macroalgal cover was assessed on a wide (˜1 km) reef flat off south-central Molokai. Macroalgae trapped a mean of 1.26 (±0.91 SD) grams of sediment per gram of dry weight biomass and that sediment was dominantly terrigenous mud (59% by weight). It was determined that biomass, as a proxy for algal size, and morphology were not strict controls on the sediment trapping process. Over 300 metric tons of sediment were estimated to be retained by macroalgae across 5.75 km 2 of reef flat (54 g m -2), suggesting that this process is an important component of sediment budgets. In addition, understanding the character of sediment trapped by macroalgae may help constrain suspended sediment flux and has implications for nutrient dynamics in reef flat environments.

Stimulation of microbial nitrogen cycling in aquatic ecosystems by benthic macrofauna: mechanisms and environmental implications

OpenAIRE

P. Stief

2013-01-01

Invertebrate animals that live at the bottom of aquatic ecosystems (i.e., benthic macrofauna) are important mediators between nutrients in the water column and microbes in the benthos. The presence of benthic macrofauna stimulates microbial nutrient dynamics through different types of animal–microbe interactions, which potentially affect the trophic status of aquatic ecosystems. This review contrasts three types of animal–microbe interactions in the benthos of aquatic ecosystems: (i) e...

Technical and Economic Evaluation of Macroalgae Cultivation for Fuel Production (Draft)

Energy Technology Data Exchange (ETDEWEB)

Feinberg, D. A.; Hock, S. M.

1985-04-01

The potential of macroalgae as sources of renewable liquid and gaseous fuels is evaluated. A series of options for production of macroalgae feedstock is considered. Because of their high carbohydrate content, the fuel products for which macroalgae are most suitable are methane and ethanol. Fuel product costs were compared with projected fuel costs in the year 1995.

Macroalgae Extracts From Antarctica Have Antimicrobial and Anticancer Potential

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Rosiane M. Martins

2018-03-01

Full Text Available Background: Macroalgae are sources of bioactive compounds due to the large number of secondary metabolites they synthesize. The Antarctica region is characterized by extreme weather conditions and abundant aggregations of macroalgae. However, current knowledge on their biodiversity and their potential for bio-prospecting is still fledging. This study evaluates the antimicrobial and cytotoxic activity of different extracts of four macroalgae (Cystosphaera jacquinotii, Iridaea cordata, Himantothallus grandifolius, and Pyropia endiviifolia from the Antarctic region against cancer and non-cancer cell lines.Methods: The antimicrobial activity of macroalgae was evaluated by the broth microdilution method. Extracts were assessed against Staphylococcus aureus ATCC 19095, Enterococcus faecalis ATCC 4083, Escherichia coli ATCC29214, Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 62342, and the clinical isolates from the human oral cavity, namely, C. albicans (3, C. parapsilosis, C. glabrata, C. lipolytica, and C. famata. Cytotoxicity against human epidermoid carcinoma (A-431 and mouse embryonic fibroblast (NIH/3T3 cell lines was evaluated with MTT colorimetric assay.Results: An ethyl acetate extract of H. grandifolius showed noticeable antifungal activity against all fungal strains tested, including fluconazole-resistant samples. Cytotoxicity investigation with a cancer cell line revealed that the ethyl acetate extract of I. cordata was highly cytotoxic against A-431 cancer cell line, increasing the inhibitory ratio to 91.1 and 95.6% after 24 and 48 h exposure, respectively, for a concentration of 500 μg mL−1. Most of the algal extracts tested showed little or no cytotoxicity against fibroblasts.Conclusion: Data suggest that macroalgae extracts from Antarctica may represent a source of therapeutic agents.HIGHLIGHTSDifferent macroalgae samples from Antarctica were collected and the lyophilized biomass of each macroalgae was extracted

Macrofauna invertebrada do solo sob diferentes sistemas de produção em Latossolo da Região do Cerrado Soil invertebrate macrofauna under different production systems in a Hapludox in the Cerrado Region

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Rogério Ferreira da Silva

2006-04-01

Full Text Available O objetivo deste trabalho foi quantificar a densidade e diversidade de grupos da comunidade de macrofauna invertebrada do solo sob diferentes sistemas de produção, bem como analisar a similaridade entre os sistemas avaliados. O trabalho foi conduzido no Município de Dourados, MS, em Latossolo Vermelho distroférrico típico, sob os seguintes sistemas: sistema convencional (SC, sistema plantio direto (SPD, sistema integração lavoura/pecuária (SILP, pastagem contínua (PC e vegetação nativa. As amostragens foram realizadas em três safras de verão e de inverno. Os valores de densidade total da comunidade de macrofauna invertebrada de solo, nos sistemas SPD, SILP e PC, foram similares, no entanto, o SPD apresentou a maior diversidade de grupos. Na safra de verão, observou-se similaridade entre os sistemas SPD e SILP e entre o SC e PC; e na safra de inverno, a similaridade foi entre os sistemas SPD, SILP e PC.The objective of this work was to quantify the density and diversity of soil invertebrate macrofauna community, in different production systems, and also to evaluate the similarity among them. The study was carried out in the Municipality of Dourados, MS, Brazil, in a Typic Hapludox under the following systems: conventional system (CS, no-tillage system (NTS, crop/livestock integration system (CLIS, continuous pasture (CP and natural system. Samples were collected during summer and winter cropping seasons. Total density and diversity of the soil invertebrate macrofauna community in the NTS, CLIS, and CP systems were similar. However, NTS showed the highest diversity. In summer, similarity was observed between NTS and CLIS, and between CS and CP, with regard to the soil invertebrate macrofauna community. In winter, similarity was among NTS, CLIS and CP.

Soil macrofauna in a Cerrado/Caatinga ecotone under different crops in Southwestern Piauí State, Brazil

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Djavan Pinheiro Santos

2017-09-01

Full Text Available ABSTRACT: The aim of this study was to characterize the soil macrofauna under different crop systems and compare them to the macrofauna under the native vegetation of a Cerrado/Caatinga ecotone in southwestern Piauí State, Brazil. The areas studied included areas under sweetsop cultivation (Annona squamosa L., andropogon grass with three years of use, andropogon grass with six years of use, pivot-irrigated corn, Napier grass, and native vegetation. In each area, soil layers of 0-0.1, 0.1-0.2, and 0.2-0.3m, including the surface litter, were evaluated following the Tropical Soil Biology and Fertility Program (TSBF recommendations. The soil macrofauna from the different land-use systems were identified to the family level, and the mean density of each taxon was calculated for each soil-management type and layer. The structure of the soil macrofauna was negatively altered under the different crops in comparison to the native Cerrado/Caatinga vegetation, with macrofaunal occurrence varying in the different soil layers. A correlation existed between the functional groups and the soil grain-size distribution and moisture. Napier grass cultivation favored greater soil macrofaunal abundance, with a predominance of families belonging to the orders Isoptera and Hymenoptera. Number of soil macrofaunal families under pivot-irrigated corn was more like the number observed with the native vegetation, and corn also had greater family diversity compared to the other crops studied. Therefore, pivot-irrigated corn can reduce the impact of anthropogenic land use on the diversity of soil macrofauna.

Assessment of Vegetation Density and Soil Macrofauna Relationship in Riparian Forest of Karkhe River for the Determination of Rivers Buffer Zone

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SH. Gholami

2014-06-01

Full Text Available The spatial distribution of soil organisms is influenced by the plant cover, thus resulting in a horizontal mosaic of areas subjected to gradients of nutrient availability and microclimatic conditions.This study was conducted to investigate the spatial variability of soil macrofauna in relation to vegetation density in the riparian forest landscape of Karkhe. The vegetation density was determined by calculating the NDVI index. Soil macrofauna were sampled using 200 sampling points along parallel transects (perpendicular to the river. The maximum distance between samples was 0.5 km. Soil macrofauna were extracted from 50 cm×50 cm×25 cm soil monolith by the hand-sorting procedure. Abundance, diversity (Shannon H’ index, richness (Menhinick index and evenness (Sheldon index were calculated. Soil macrofauna and NDVI data were analyzed using geostatistics (variogram in order to describe and quantify the spatial continuity. The variograms were spherical, revealing the presence of spatial autocorrelation. The range of influence was 1724 m for abundance, 1326 m for diversity, 1825 m for richness, 1450 for evenness and 1977 m for NDVI. The kriging maps showed that the NDVI Index and soil macrofauna had spatial variability. The spatial pattern of soil macrofauna abundance and biodiversity were similar to the spatial pattern of vegetation density as shown in the correlation.

Effective production of fermentable sugars from brown macroalgae biomass.

Science.gov (United States)

Wang, Damao; Kim, Do Hyoung; Kim, Kyoung Heon

2016-11-01

Brown macroalgae are renewable and sustainable biomass resources for the production of biofuels and chemicals, owing to their high levels of carbohydrates and low levels of lignin. To increase the biological usage of brown macroalgae, it is necessary to depolymerize the polysaccharides that generate macroalgal monomeric sugars or sugar derivatives and to convert them into fermentable sugars for the production of biofuels and chemicals. In this review, we discuss the chemical and enzymatic saccharification of the major carbohydrates found in brown macroalgae and the use of the resulting constituents in the production of biofuels and chemicals, as well as high-value health-benefiting functional oligosaccharides and sugars. We also discuss recently reported experimental results, novel enzymes, and technological breakthroughs that are related to polysaccharide depolymerization, fermentable sugar production, and the biological conversion of non-favorable sugars for fermentation using industrial microorganisms. This review provides a comprehensive perspective of the efficient utilization of brown macroalgae as renewable resources for the production of biofuels and chemicals.

Edaphic macrofauna as biological indicator of the conservation/disturbance status of soil. Results obtained in Cuba

International Nuclear Information System (INIS)

Cabrera, Grisel

2012-01-01

In order to predict the degradation status of a soil, a group of variables comprising its physical, chemical and/or biological properties is used. Macrofauna, which includes soil invertebrates higher than 2 mm of diameter, is a biological component that can be used for such purpose. Its taxonomic richness as well as its density, biomass and functional composition change depending on the effect of diverse land uses and managements. This review reaffirms that the macrofauna characteristics and the results obtained, mainly in Cuba, about its variation in ecosystems with different anthropization levels, support the potential use of this fauna as biological indicator of the soil's conservation status. Future studies should consider a lower taxonomic level in the identification of macrofauna, and relate its taxonomic and functional composition to the climate and pedological factors. (author)

Effect of direct seeding mulch-based systems on soil carbon storage and macrofauna in central Brazil

Energy Technology Data Exchange (ETDEWEB)

Blanchart, E.; Bernoux, M.; Sarda, X.; Feller, C. [Institut de Recherche pour le Developpement, Montpellier (France); Siqueira Neto, M.; Cerri, C.C.; Piccolo, M. [CENA-USP, Piracicaba (Brazil). Lab. Biogeoquimica Ambiental; Douzet, J.M. [CIRAD, Antsirabe (Madagascar); Scopel, E. [CIRAD-CA, Planaltina (Brazil)

2007-07-01

Soils represent a large carbon pool, approximately 1500 Gt, equivalent to almost three times the quantity stored in terrestrial biomass and twice the amount stored in the atmosphere. The management and maintenance of soil carbon is therefore an integral part of the global carbon cycle. Land use change, inappropriate agricultural practices and climate change can all lead to a net release of C from soils to the atmosphere, exacerbating the problems of greenhouse gas release. Any modification of land-use or land management can induce variations in soil carbon stocks, even in agricultural systems that are perceived to be in a steady state. These modifications also alter soil macrofauna that is known to affect soil carbon dynamics. Direct seeding Mulch-based Cropping (DMC) systems with two crops per year without soil tillage have widely been adopted over the last 10 to 15 years in the Cerrado (central region) of Brazil. They are replacing the traditional soybean monocropping with fallow under conventional tillage (CT). Th e objective of this study was to examine how DMC practices affect soil organic carbon (SOC) dynamics and macrofauna (Rio Verde, Goias State). The approach was to determine soil C stocks and macrofauna in five fi elds under DMC aged 1, 5, 7, 11 and 13 years. In order to compare DMC systems with the native system of the region and previous land-use, a situation under native Cerrado (tree-savanna like vegetation) and a field conducted traditionally (CT) were also studied. Soil C stocks were calculated for the 0-10 and 0-40 cm soil depth and also for the fi rst 400 kg m{sup -2} of soil to compare the same amount of soil and to suppress the potential artefact of soil compaction when sample is based on fix layer depth. Soil macrofauna was hand-sorted from soil monoliths (30 cm depth, TSBF method). In our study, the annual rate of carbon storage was equal to ca. 1.6 MgC ha{sup -1}, which is in the range of values measured for DMC in different areas of Brazil

Macroalgae - an environmental problem or a resource from an eMergy perspective?

DEFF Research Database (Denmark)

Seghetta, Michele; Østergård, Hanne; Bastianoni, Simone

Eutrophication is an environmental problem in a majority of shallow water basins all over the world. The flow of nutrients into the water basin leads to an undesired flowering of macroalgae and their decomposition decreases dissolved oxygen which hampers heterothrophic organisms from breathing....... Could the macroalgae biomass be harvested and used for biofuels in a sustainable way? Two case studies are analyzed: Orbetello Lagoon, Italy, and Køge bay, Denmark. Today, macroalgae are collected and stored in landfills to limit the problem. This study models a scenario where the macroalgae are used...

EFFECT OF LEGUME TREES ON SOIL MACROFAUNA OF A Brachiaria brizantha cv. MARANDU PASTURE EFEITO DE LEGUMINOSAS ARBÓREAS SOBRE A MACROFAUNA DO SOLO EM PASTAGEM DE Brachiaria brizantha cv. MARANDU

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Avílio Antonio Franco

2007-09-01

Full Text Available

The objective of this research was to evaluate the effect of four legume tree species in a Brachiaria brizantha cv. Marandu pasture on soil macrofauna density and diversity, in a low natural fertility soil. The tree leguminous species introduced in the pasture were Pseudosamanea guachapele, Mimosa artemisiana, Mimosa tenuiflora, and Enterolobium contortisiliquum. The macrofauna sampling consisted in collecting six soil monoliths with 25 cm x 25 cm x 30 cm under tree canopies or in a transect in the single Brachiaria pasture. The densities varied from 602 individuals.m-2 under the canopy of E. contortisiliquum to two individuals.m-2 in the single pasture. The largest group richness was found under M. tenuiflora canopy (ten groups, followed by P. guachapele (nine groups, E. contortisiliquum (seven groups and M. artemisiana (six groups. The leguminous species influence was related to N content and to C:N ratio of leaf material. M. artemisiana and M. tenuiflora favored the occurrence of Oligochaeta and Coleoptera larvae, while under the P. guachapele and E. contortisiliquum canopies Formicidae activity was more intense.

KEY-WORDS: Soil macrofauna; sivipastoral systems; soil quality.

O objetivou deste trabalho foi avaliar o efeito de quatro espécies leguminosas arbóreas, em uma pastagem de Brachiaria brizantha cv. Marandu, com dois anos de estabelecimento, sobre a densidade e diversidade da macrofauna de um planossolo de baixa fertilidade natural. As espécies arbóreas introduzidas na pastagem foram: Pseudosamanea guachapele, Mimosa artemisiana, Mimosa tenuiflora e Enterolobium contortisiliquum. A amostragem da macrofauna consistiu na retirada de seis monolitos de solo com 25 cm x 25 cm x 30 cm sob a copa das árvores ou em um transecto na pastagem solteira. As densidades variaram de 602

Role of marine macroalgae in plant protection & improvement for sustainable agriculture technology

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Seham M. Hamed

2018-03-01

Full Text Available Marine macroalgae are plant-like organisms with simple internal structures that generally live in coastal areas. They mainly include different communities of red, brown and green macroalgae. Marine macroalgae commonly occupy intertidal and sublittoral-to-littoral zones on rocks and other hard substrata. They are considered to be an excellent natural biosource in different aspects of agricultural fields. They have great proficiency in improving soil physical and chemical properties. Marine macroalgae are also characterized by producing a large array of biologically active biocidal substances against plant-infecting pathogens. Unfortunately, most available literatures on marine macroalgae and their derivatives mainly focused on their pharmaceutical applications but their potential utilization in sustainable agriculture development is still often regarded as a secondary goal. However, a relatively considerable dataset on marine macroalgae showed that they could play a major role in plant protection and improvement. This review summarizes different aspects of potential macroalgal applications in agriculture. Commercial production and exploitation of specific compounds with interesting biotechnological importance from marine macroalgae including microbicides, nematicides, insecticides, biofertilizers, biostimulators and soil conditioners are highlighted and discussed in detail. Bioactive compounds like fatty acids (in particular polyunsaturated fatty acids (PUFAs, proteins (amino acids, bioflavonoids, sulfated polysaccharides, carotenoids, polyphenols and carbohydrates are considered to have bactericidal, antiviral and fungicidal effects against some plant-infecting pathogens. These biocontrol agents provide multiple benefits and act as useful pointers for improving cultivation practices in diverse habitats. Marine macroalgae can be generally considered as promising multifunctional bioinoculants and ecofriendly environmental tools in recent trends

Checklist of Macroalgae in Waisai Coast, Raja Ampat

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Retno Suryandari

2016-05-01

Full Text Available Macroalgae are very abundant organisms in Indonesian coastal zone. They comprise 8.6% of the total marine organisms.The aim of the research was to identify macroalgae in Waisai Coast Raja Ampat. The results showed that 38 macroalgae were found in Waisai Coast Raja Ampat but only 29 species of macroalgae can be identified. Macroalgae found in Waisai Coast Raja Ampat are green algae, red algae and brown algae. Green algae found and identified are Caulerpa macra (Weber-van Bosse Draisma & Prud’homme, Caulerpa racemosa var. macrophysa (Sonder wx Kutzing W.R.Taylor,  Caulerpa sertularoides (S. Gmelin Howe f. brevipes (J. Agardh Svedilus, Caulerpa cupressoides (Vahl C. Agardh, Halimeda discoidea Decaisne, Halimeda Opuntia (Linnaeus J.V. Lamoroux, Halimeda tuna (J. Ellis & Solander J.V. Lamoroux, Halimeda cylindraceae Decaisne, Halimeda macroloba Decaisne, Avrainvillea erecta (Berkeley A. Gepp & E.S. Gepp, Codium geppiorum O.C.Schmidt, Boergesenia forbesii (Hardvey Feldmann, Valonia ventricosa J. Agardh, Dictyosphaeria cavernosa (Forsskål Børgesen, Chaetomorpha spiralisOkamura, Anadyomene wrightii Harvey ex. J. E. Gray, Neomeris annulata Dickie. Red algae species found and successfully identified areAcanthophora spicifera (M. Vahl Børgesen, Laurencia papilosa (C. Agardh Greville, Gracilaria salicornia (C. Agardh E.Y. Dawson, Amphiora fragilissima (Linnaeus J.V. Lamoroux, Hypnea pannosa J. Agardh. Brown algae species  found and identified are Hormophysa cuneiformis (J.F. Gmelin P.C. Silva, Sargassum aquifolium (Turner C. Agardh, Sargassum polycystum C. Agardh, Turbinaria ornata (Turner J. Agardh, Padina australis Hauck, Canistrocarpus cervicornis (Kutzing De Paula & De Clerck Hydroclathrus clatratus (C. Agardh M. Howe. The only species found in Indonesia is Sargassum aquifolium.

Microphytobenthos and benthic macroalgae determine sediment organic matter composition in shallow photic sediments

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A. K. Hardison

2013-08-01

Full Text Available Microphytobenthos and benthic macroalgae play an important role in system metabolism within shallow coastal bays. However, their independent and interactive influences on sediment organic matter (SOM are not well understood. We investigated the influence of macroalgae and microphytobenthos on SOM quantity and quality in an experimental mesocosm system using bulk and molecular level (total hydrolyzable amino acids, THAA; phospholipid linked fatty acids, PLFA; pigment analyses. Our experiment used an incomplete factorial design made up of two factors, each with two levels: (1 light (ambient vs. dark and (2 macroalgae (presence vs. absence of live macroalgae. Over the course of the 42-day experiment, total organic carbon (TOC and total nitrogen (TN increased under ambient light by 173 ± 14 and 141 ± 7%, respectively, compared to in the dark (78 ± 29 and 39 ± 22%. THAA comprised a substantial fraction of SOM (~ 16% of TOC, 35% of TN and followed TOC and TN accumulation patterns. Mole percent composition of the THAA pool indicated that SOM was composed of more labile organic material (e.g., L-glutamic acid, phenylalanine under ambient light conditions while SOM in dark treatments was more degraded, with higher proportions of glycine and D-alanine. PLFA content, which represents viable biomass, made up ~ 1% of TOC and contained high levels of algal fatty acids in the light, particularly PLFA derived from diatoms. In the presence of microphytobenthos (i.e., light and macroalgae treatments, SOM lability increased, resulting in the observed increases in bacterial PLFA concentrations. Macroalgae, which were added to half of the light treatments, decreased SOM accumulation compared to light treatments without macroalgae, with TOC and TN increasing by only 130 ± 32 and 94 ± 24%, respectively. This decrease likely resulted from shading by macroalgae, which reduced production of microphytobenthos. The presence of macroalgae decreased SOM lability as

Microphytobenthos and benthic macroalgae determine sediment organic matter composition in shallow photic sediments

Science.gov (United States)

Hardison, A. K.; Canuel, E. A.; Anderson, I. C.; Tobias, C. R.; Veuger, B.; Waters, M. N.

2013-08-01

Microphytobenthos and benthic macroalgae play an important role in system metabolism within shallow coastal bays. However, their independent and interactive influences on sediment organic matter (SOM) are not well understood. We investigated the influence of macroalgae and microphytobenthos on SOM quantity and quality in an experimental mesocosm system using bulk and molecular level (total hydrolyzable amino acids, THAA; phospholipid linked fatty acids, PLFA; pigment) analyses. Our experiment used an incomplete factorial design made up of two factors, each with two levels: (1) light (ambient vs. dark) and (2) macroalgae (presence vs. absence of live macroalgae). Over the course of the 42-day experiment, total organic carbon (TOC) and total nitrogen (TN) increased under ambient light by 173 ± 14 and 141 ± 7%, respectively, compared to in the dark (78 ± 29 and 39 ± 22%). THAA comprised a substantial fraction of SOM (~ 16% of TOC, 35% of TN) and followed TOC and TN accumulation patterns. Mole percent composition of the THAA pool indicated that SOM was composed of more labile organic material (e.g., L-glutamic acid, phenylalanine) under ambient light conditions while SOM in dark treatments was more degraded, with higher proportions of glycine and D-alanine. PLFA content, which represents viable biomass, made up ~ 1% of TOC and contained high levels of algal fatty acids in the light, particularly PLFA derived from diatoms. In the presence of microphytobenthos (i.e., light and macroalgae treatments), SOM lability increased, resulting in the observed increases in bacterial PLFA concentrations. Macroalgae, which were added to half of the light treatments, decreased SOM accumulation compared to light treatments without macroalgae, with TOC and TN increasing by only 130 ± 32 and 94 ± 24%, respectively. This decrease likely resulted from shading by macroalgae, which reduced production of microphytobenthos. The presence of macroalgae decreased SOM lability as well, which

Modelling the effects of drifting macroalgae in coastal waters

DEFF Research Database (Denmark)

Canal Vergés, Paula; Jørgensen, Charlotte; Flindt, Mogens

2009-01-01

It is well-known that opportunistic macroalgae starts to drift at low current velocities (Flindt et al. 2007) and that the nutrient transport in many aquatic systems are dominated by this process. New studies have shown, that at this current velocities, macroalgae moves as bedload transport creat...... obtained by flume experiments and field observations in protected and semi-protected shallow estuarine waters....

Modelling potential production of macroalgae farms in UK and Dutch coastal waters

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J. van der Molen

2018-02-01

Full Text Available There is increasing interest in macroalgae farming in European waters for a range of applications, including food, chemical extraction for biofuel production. This study uses a 3-D numerical model of hydrodynamics and biogeochemistry to investigate potential production and environmental effects of macroalgae farming in UK and Dutch coastal waters. The model included four experimental farms in different coastal settings in Strangford Lough (Northern Ireland, in Sound of Kerrera and Lynn of Lorne (north-west Scotland and in the Rhine plume (the Netherlands, as well as a hypothetical large-scale farm off the UK north Norfolk coast. The model could not detect significant changes in biogeochemistry and plankton dynamics at any of the farm sites averaged over the farming season. The results showed a range of macroalgae growth behaviours in response to simulated environmental conditions. These were then compared with in situ observations where available, showing good correspondence for some farms and less good correspondence for others. At the most basic level, macroalgae production depended on prevailing nutrient concentrations and light conditions, with higher levels of both resulting in higher macroalgae production. It is shown that under non-elevated and interannually varying winter nutrient conditions, farming success was modulated by the timings of the onset of increasing nutrient concentrations in autumn and nutrient drawdown in spring. Macroalgae carbohydrate content also depended on nutrient concentrations, with higher nutrient concentrations leading to lower carbohydrate content at harvest. This will reduce the energy density of the crop and thus affect its suitability for conversion into biofuel. For the hypothetical large-scale macroalgae farm off the UK north Norfolk coast, the model suggested high, stable farm yields of macroalgae from year to year with substantial carbohydrate content and limited environmental effects.

Modelling potential production of macroalgae farms in UK and Dutch coastal waters

Science.gov (United States)

van der Molen, Johan; Ruardij, Piet; Mooney, Karen; Kerrison, Philip; O'Connor, Nessa E.; Gorman, Emma; Timmermans, Klaas; Wright, Serena; Kelly, Maeve; Hughes, Adam D.; Capuzzo, Elisa

2018-02-01

There is increasing interest in macroalgae farming in European waters for a range of applications, including food, chemical extraction for biofuel production. This study uses a 3-D numerical model of hydrodynamics and biogeochemistry to investigate potential production and environmental effects of macroalgae farming in UK and Dutch coastal waters. The model included four experimental farms in different coastal settings in Strangford Lough (Northern Ireland), in Sound of Kerrera and Lynn of Lorne (north-west Scotland) and in the Rhine plume (the Netherlands), as well as a hypothetical large-scale farm off the UK north Norfolk coast. The model could not detect significant changes in biogeochemistry and plankton dynamics at any of the farm sites averaged over the farming season. The results showed a range of macroalgae growth behaviours in response to simulated environmental conditions. These were then compared with in situ observations where available, showing good correspondence for some farms and less good correspondence for others. At the most basic level, macroalgae production depended on prevailing nutrient concentrations and light conditions, with higher levels of both resulting in higher macroalgae production. It is shown that under non-elevated and interannually varying winter nutrient conditions, farming success was modulated by the timings of the onset of increasing nutrient concentrations in autumn and nutrient drawdown in spring. Macroalgae carbohydrate content also depended on nutrient concentrations, with higher nutrient concentrations leading to lower carbohydrate content at harvest. This will reduce the energy density of the crop and thus affect its suitability for conversion into biofuel. For the hypothetical large-scale macroalgae farm off the UK north Norfolk coast, the model suggested high, stable farm yields of macroalgae from year to year with substantial carbohydrate content and limited environmental effects.

Design and Analysis of Offshore Macroalgae Biorefineries.

Science.gov (United States)

Golberg, Alexander; Liberzon, Alexander; Vitkin, Edward; Yakhini, Zohar

2018-03-15

Displacing fossil fuels and their derivatives with renewables, and increasing sustainable food production are among the major challenges facing the world in the coming decades. A possible, sustainable direction for addressing this challenge is the production of biomass and the conversion of this biomass to the required products through a complex system coined biorefinery. Terrestrial biomass and microalgae are possible sources; however, concerns over net energy balance, potable water use, environmental hazards, and uncertainty in the processing technologies raise questions regarding their actual potential to meet the anticipated food, feed, and energy challenges in a sustainable way. Alternative sustainable sources for biorefineries are macroalgae grown and processed offshore. However, implementation of the offshore biorefineries requires detailed analysis of their technological, economic, and environmental performance. In this chapter, the basic principles of marine biorefineries design are shown. The methods to integrate thermodynamic efficiency, investment, and environmental aspects are discussed. The performance improvement by development of new cultivation methods that fit macroalgae physiology and development of new fermentation methods that address macroalgae unique chemical composition is shown.

Edaphic macrofauna as biological indicator of the conservation/disturbance status of soil. Results obtained in Cuba; La macrofauna edáfica como indicador biológico del estado de conservación/perturbación del suelo. Resultados obtenidos en Cuba

Energy Technology Data Exchange (ETDEWEB)

Cabrera, Grisel [Instituto de Ecología y Sistemática, CITMA. Carretera de Varona km 3 1/2 Capdevila, Boyeros, La Habana 19 CP 11900 (Cuba)

2012-07-01

In order to predict the degradation status of a soil, a group of variables comprising its physical, chemical and/or biological properties is used. Macrofauna, which includes soil invertebrates higher than 2 mm of diameter, is a biological component that can be used for such purpose. Its taxonomic richness as well as its density, biomass and functional composition change depending on the effect of diverse land uses and managements. This review reaffirms that the macrofauna characteristics and the results obtained, mainly in Cuba, about its variation in ecosystems with different anthropization levels, support the potential use of this fauna as biological indicator of the soil's conservation status. Future studies should consider a lower taxonomic level in the identification of macrofauna, and relate its taxonomic and functional composition to the climate and pedological factors. (author)

Trait modality distribution of aquatic macrofauna communities as explained by pesticides and water chemistry.

Science.gov (United States)

Ieromina, O; Musters, C J M; Bodegom, P M; Peijnenburg, W J G M; Vijver, M G

2016-08-01

Analyzing functional species' characteristics (species traits) that represent physiological, life history and morphological characteristics of species help understanding the impacts of various stressors on aquatic communities at field conditions. This research aimed to study the combined effects of pesticides and other environmental factors (temperature, dissolved oxygen, dissolved organic carbon, floating macrophytes cover, phosphate, nitrite, and nitrate) on the trait modality distribution of aquatic macrofauna communities. To this purpose, a field inventory was performed in a flower bulb growing area of the Netherlands with significant variation in pesticides pressures. Macrofauna community composition, water chemistry parameters and pesticide concentrations in ditches next to flower bulb fields were determined. Trait modalities of nine traits (feeding mode, respiration mode, locomotion type, resistance form, reproduction mode, life stage, voltinism, saprobity, maximum body size) likely to indicate pesticides impacts were analyzed. According to a redundancy analysis, phosphate -and not pesticides- constituted the main factor structuring the trait modality distribution of aquatic macrofauna. The functional composition could be ascribed for 2-4 % to pesticides, and for 3-11 % to phosphate. The lack of trait responses to pesticides may indicate that species may have used alternative strategies to adapt to ambient pesticides stress. Biomass of animals exhibiting trait modalities related to feeding by predation and grazing, presence of diapause form or dormancy, reproduction by free clutches and ovoviviparity, life stage of larvae and pupa, was negatively correlated to the concentration of phosphate. Hence, despite the high pesticide pollution in the area, variation in nutrient-related stressors seems to be the dominant driver of the functional composition of aquatic macrofauna assembly in agricultural ditches.

Communities of soil macrofauna in green spaces of an urbanizing city at east China Comunidades de macrofauna del suelo en espacios verdes de una ciudad en proceso de urbanización en el este de China

Directory of Open Access Journals (Sweden)

GE BAO-MING

2012-06-01

Full Text Available We evaluated the diversity of soil macrofauna communities inhabiting urban green spaces in Yancheng City, an urbanizing city located east of China. In the end of April 2011, the taxonomic richness, abundance and composition of soil macrofauna communities were assessed and compared among five types of green space (poplar forest, rapeseed farm, grassland in park, lawn and nursery garden and three depth layers in the soil, with taxonomic resolution attained at the order level. Taxonomic richness (orders and abundance were significantly different among green spaces. Diversity indices (Margalef's taxonomic richness R and Shannon-Weaver diversity index H' were higher in poplar forest, grassland in park and nursery garden than in rapeseed farm and lawn. Taxonomic richness (Chao 2 showed a similar trend. There were significant effects of green space type and soil layer, which showed a significant interaction affecting macrofauna composition. We recommend that urban green spaces can be used for maintaining biodiversity, not only for landscape purposes.Evaluamos la diversidad de las comunidades de macrofauna del suelo que habitan los espacios verdes urbanos en la ciudad de Yancheng, una ciudad en proceso de urbanización situada al este de China. A fines de abril 2011, la riqueza taxonómica, abundancia y composición de comunidades de macrofauna del suelo fueron evaluadas y comparadas entre cinco tipos de espacio verde (bosque de álamos, granja de colza, pastizal de parque, césped y jardín vivero y tres capas de profundidad del suelo, con resolución taxonómica a nivel de orden. La riqueza taxonómica (de órdenes y la abundancia fueron significativamente diferentes entre los espacios verdes. Los indices de diversidad (riqueza taxonómica R de Margalef y diversidad H' de Shannon-Weaver fueron mayores en el bosque de álamos, pastizal de parque y jardin vivero que en la granja de la colza y el césped. La riqueza taxonómica (Chao 2 mostró una

Macroalgae Decrease Growth and Alter Microbial Community Structure of the Reef-Building Coral, Porites astreoides

Science.gov (United States)

Vega Thurber, Rebecca; Burkepile, Deron E.; Correa, Adrienne M. S.; Thurber, Andrew R.; Shantz, Andrew A.; Welsh, Rory; Pritchard, Catharine; Rosales, Stephanie

2012-01-01

With the continued and unprecedented decline of coral reefs worldwide, evaluating the factors that contribute to coral demise is of critical importance. As coral cover declines, macroalgae are becoming more common on tropical reefs. Interactions between these macroalgae and corals may alter the coral microbiome, which is thought to play an important role in colony health and survival. Together, such changes in benthic macroalgae and in the coral microbiome may result in a feedback mechanism that contributes to additional coral cover loss. To determine if macroalgae alter the coral microbiome, we conducted a field-based experiment in which the coral Porites astreoides was placed in competition with five species of macroalgae. Macroalgal contact increased variance in the coral-associated microbial community, and two algal species significantly altered microbial community composition. All macroalgae caused the disappearance of a γ-proteobacterium previously hypothesized to be an important mutualist of P. astreoides. Macroalgal contact also triggered: 1) increases or 2) decreases in microbial taxa already present in corals, 3) establishment of new taxa to the coral microbiome, and 4) vectoring and growth of microbial taxa from the macroalgae to the coral. Furthermore, macroalgal competition decreased coral growth rates by an average of 36.8%. Overall, this study found that competition between corals and certain species of macroalgae leads to an altered coral microbiome, providing a potential mechanism by which macroalgae-coral interactions reduce coral health and lead to coral loss on impacted reefs. PMID:22957055

Macroalgae decrease growth and alter microbial community structure of the reef-building coral, Porites astreoides.

Directory of Open Access Journals (Sweden)

Rebecca Vega Thurber

Full Text Available With the continued and unprecedented decline of coral reefs worldwide, evaluating the factors that contribute to coral demise is of critical importance. As coral cover declines, macroalgae are becoming more common on tropical reefs. Interactions between these macroalgae and corals may alter the coral microbiome, which is thought to play an important role in colony health and survival. Together, such changes in benthic macroalgae and in the coral microbiome may result in a feedback mechanism that contributes to additional coral cover loss. To determine if macroalgae alter the coral microbiome, we conducted a field-based experiment in which the coral Porites astreoides was placed in competition with five species of macroalgae. Macroalgal contact increased variance in the coral-associated microbial community, and two algal species significantly altered microbial community composition. All macroalgae caused the disappearance of a γ-proteobacterium previously hypothesized to be an important mutualist of P. astreoides. Macroalgal contact also triggered: 1 increases or 2 decreases in microbial taxa already present in corals, 3 establishment of new taxa to the coral microbiome, and 4 vectoring and growth of microbial taxa from the macroalgae to the coral. Furthermore, macroalgal competition decreased coral growth rates by an average of 36.8%. Overall, this study found that competition between corals and certain species of macroalgae leads to an altered coral microbiome, providing a potential mechanism by which macroalgae-coral interactions reduce coral health and lead to coral loss on impacted reefs.

Antimicrobial activity of extracts from macroalgae Ulva lactuca against clinically important Staphylococci is impacted by lunar phase of macroalgae harvest.

Science.gov (United States)

Deveau, A M; Miller-Hope, Z; Lloyd, E; Williams, B S; Bolduc, C; Meader, J M; Weiss, F; Burkholder, K M

2016-05-01

Staphylococcus aureus is a common human bacterial pathogen that causes skin and soft tissue infections. Methicillin-resistant Staph. aureus (MRSA) are increasingly drug-resistant, and thus there is great need for new therapeutics to treat Staph. aureus infections. Attention has focused on potential utility of natural products, such as extracts of marine macroalgae, as a source of novel antimicrobial compounds. The green macroalgae Ulva lactuca produces compounds inhibitory to human pathogens, although the effectiveness of U. lactuca extracts against clinically relevant strains of Staph. aureus is poorly understood. In addition, macroalgae produce secondary metabolites that may be influenced by exogenous factors including lunar phase, but whether lunar phase affects U. lactuca antimicrobial capacity is unknown. We sought to evaluate the antibacterial properties of U. lactuca extracts against medically important Staphylococci, and to determine the effect of lunar phase on antimicrobial activity. We report that U. lactuca methanolic extracts inhibit a range of Staphylococci, and that lunar phase of macrolagae harvest significantly impacts antimicrobial activity, suggesting that antimicrobial properties can be maximized by manipulating time of algal harvest. These findings provide useful parameters for future studies aimed at isolating and characterizing U. lactuca anti-Staphylococcal agents. The growing prevalence of antibiotic-resistant human pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) has intensified efforts towards discovery and development of novel therapeutics. Marine macroalgae like Ulva lactuca are increasingly recognized as potential sources of antimicrobials, but the efficacy of U. lactuca extracts against common, virulent strains of Staph. aureus is poorly understood. We demonstrate that U. lactuca methanolic extracts inhibit a variety of clinically relevant Staphylococcus strains, and that the antimicrobial activity can

Content of polyphenol compound in mangrove and macroalga extracts

Science.gov (United States)

Takarina, N. D.; Patria, M. P.

2017-07-01

Polyphenol or phenolic are compounds containing one or more hydroxyl group of the aromatic ring [1]. These compounds have some activities like antibacterial, antiseptic, and antioxidants. Natural resources like mangrove and macroalga were known containing these compounds. The purpose of the research was to investigate polyphenol content in mangrove and macroalga. Materials used in this research were mangrove (Avicennia sp.) leaves and the whole part of macroalga (Caulerpa racemosa). Samples were dried for 5 days then macerated in order to get an extract. Maceration were done using methanol for 48 hours (first) and 24 hours (second) continously. Polyphenol content was determined using phytochemical screening on both extracts. The quantitative test was carried out to determine catechin and tannin as polyphenol compound. The result showed that catechin was observed in both extracts while tannin in mangrove extract only. According to quantitative test, mangrove has a higher content of catechin and tannin which were 12.37-13.44 % compared to macroalga which was 2.57-4.58 %. Those indicated that both materials can be the source of polyphenol compound with higher content on mangrove. Moreover, according to this result, these resources can be utilized for advanced studies and human needs like medical drug.

The effect of soil macrofauna on water regime of post mining soils

Czech Academy of Sciences Publication Activity Database

Frouz, Jan; Kuráž, V.

2008-01-01

Roč. 10, - (2008) ISSN 1029-7006. [EGU General Assembly 2008. 13.04.2008-18.04.2008, Vienna] Institutional research plan: CEZ:AV0Z60660521 Keywords : soil macrofauna * water regime * post mining soil s Subject RIV: EH - Ecology, Behaviour

Biogas from Macroalgae: is it time to revisit the idea?

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Hughes Adam D

2012-11-01

Full Text Available Abstract The economic and environmental viability of dedicated terrestrial energy crops is in doubt. The production of large scale biomass (macroalgae for biofuels in the marine environment was first tested in the late 1960’s. The culture attempts failed due to the engineering challenges of farming offshore. However the energy conversion via anaerobic digestion was successful as the biochemical composition of macroalgae makes it an ideal feedstock. The technology for the mass production of macroalgae has developed principally in China and Asia over the last 50 years to such a degree that it is now the single largest product of aquaculture. There has also been significant technology transfer and macroalgal cultivation is now well tried and tested in Europe and America. The inherent advantage of production of biofuel feedstock in the marine environment is that it does not compete with food production for land or fresh water. Here we revisit the idea of the large scale cultivation of macroalgae at sea for subsequent anaerobic digestion to produce biogas as a source of renewable energy, using a European case study as an example.

Transuranium elements in macroalgae at Monaco following the Chernobyl accident

International Nuclear Information System (INIS)

Holm, E.; Ballestra, S.; Lopez, J.J.; Barci-Funel, G.; Ardisson, G.

1991-01-01

The atmospheric deposition and transfer of transuranium elements (TU) to macroalgae at Monaco following the Chernobyl accident has been studied. The deposition of TU was small compared to most fission products: 239+240 Pu and 241 Am could not be detected in water or algae, 242 Cm was the dominant α emitter detected in Chernobyl fallout. Concentration factors of TU for the macroalgae are estimated

Bioremediation capacity, nutritional value and biorefining of macroalga Saccharina latissima

DEFF Research Database (Denmark)

Silva Marinho, Goncalo

Macroalgae have the ability to assimilate and convert waste nutrients (N and P) into valuable biomass. In this context, they have been extensively studied for their bioremediation potential for integrated multi-trophic aquaculture (IMTA). With a global aquaculture production of 23.8 million tonnes...... attention as sustainable feedstock for biorefinery. Nevertheless, macroalgae resources are still very little explored in western countries. The aim of this study was fulfilled by the investigation of the bioremediation potential of the macroalga Saccharina latissima cultivated at a reference site (control...... two growing seasons enhanced the biomass yield and thus value, but not the bioremediation capacity. Harvest time had a significant impact in overall chemical composition, while cultivation site did not generally result in marked differences. The growth of epiphytic organisms from July to November...

Soil macrofauna functional groups and their effects on soil structure, as related to agricultural management practices across agroecological zones of Sub-Saharan Africa

NARCIS (Netherlands)

Ayuke, F.O.

2010-01-01

This study aimed at understanding the effects of crop management practices on soil macrofauna and the links with soil aggregation and soil organic matter dynamics, which is key to the improvement of infertile or degrading soils in Sub-Sahara Africa. Soil macrofauna, especially earthworms and

Studies on the intertidal macrofauna of the sandy beach at Kavarati atoll (Lakshadweep)

Digital Repository Service at National Institute of Oceanography (India)

Narayanan, B.; Sivadas, P.

The distribution of macrofauna in Kavaratti Atoll is studied in the intertidal region for over a period of 13 months. Several diversity in the faunal composition was not observed. The polychaete Scoloplos sp. and the bivalve Mesodesma glabratum were...

Macroalgae-Derived Ingredients for Cosmetic Industry—An Update

Directory of Open Access Journals (Sweden)

Filipa B. Pimentel

2017-12-01

Full Text Available Aging is a natural and progressive declining physiological process that is influenced by multifactorial aspects and affects individuals’ health in very different ways. The skin is one of the major organs in which aging is more evident, as it progressively loses some of its natural functions. With the new societal paradigms regarding youth and beauty have emerged new concerns about appearance, encouraging millions of consumers to use cosmetic/personal care products as part of their daily routine. Hence, cosmetics have become a global and highly competitive market in a constant state of evolution. This industry is highly committed to finding natural sources of functional/bioactive-rich compounds, preferably from sustainable and cheap raw materials, to deliver innovative products and solutions that meet consumers’ expectations. Macroalgae are an excellent example of a natural resource that can fit these requirements. The incorporation of macroalgae-derived ingredients in cosmetics has been growing, as more and more scientific evidence reports their skin health-promoting effects. This review provides an overview on the possible applications of macroalgae as active ingredients for the cosmetic field, highlighting the main compounds responsible for their bioactivity on skin.

Small scale morphodynamics of shoreface-connected ridges and their impact on benthic macrofauna

Science.gov (United States)

Markert, Edith; Kröncke, Ingrid; Kubicki, Adam

2015-05-01

The first interdisciplinary analysis (biological and sedimentological) of macrofauna communities influenced by long-term morphodynamics of shoreface-connected ridges in the German Bight on a small scale is presented in this study. The study area covering 4 km2 was located off the island of Spiekeroog, in an area known as a Tellina fabula community. Sediment samples taken at 27 sample sites were coupled with side-scan sonar data to draw a precise sediment map of the area, as well as with high-resolution multi-beam bathymetry data to understand the morphodynamic changes of the seabed between 2003 and 2010. The macrofauna data acquired at the same 27 sites were analysed for community structure using non-metric multidimensional scaling, the ANOSIM and PERMANOVA tests. Correlations between biological and environmental variables were examined with the BIOENV procedure. The study revealed a shore-parallel sediment zonation with clear and sharp borders induced by local morphodynamics, which together with specific local bathymetry affected the formation of three different macrofauna affinity groups. One group was located on the shoreface and in the troughs (dominant species: Scoloplos armiger, Lanice conchilega, Notomastus latericeus), one on the landward flanks of the ridges (dominant species: Aonides paucibranchiata, Goniadella bobretzkii), and one on the ridge crests (dominant species: Ophelia spp. juv., Spio goniocephala). The spatial distribution of the affinity groups, their taxa number and abundance of species was dependent on a surface sediment pattern resulting from local hydrodynamics, which in turn is known to influence the food availability. A seaward steepening of ridges took place and was an effect of erosion up to 0.34 m on landward flanks in and accumulation up to 0.29 m on seaward flanks in seven years. The studied shoreface-connected ridges migrated seawards with a pace of 5 m/year for the large ridge and 20 m/year for the small ridge. Elongated mud

Environmental variation and macrofauna response in a coastal area influenced by land runoff

Science.gov (United States)

Akoumianaki, Ioanna; Papaspyrou, Sokratis; Kormas, Konstantinos Ar.; Nicolaidou, Artemis

2013-11-01

Macrofauna community interactions with environmental variables in the water column (salinity, temperature, turbidity, transparency, suspended particulate matter, particulate organic matter, choloroplastic pigments) and in the sediment (granulometric variables, organic carbon and pigments) were investigated in a coastal area with high land runoff due to riverine and temporary stream discharges (Greece, Aegean Sea, Maliakos Gulf). Samples were taken along a distance-depositional gradient from the river mouth to the open sea at eight stations, at times of different precipitation regime from August 2000 to May 2001. The physical variables, such as transparency and median grain size, generally increased seawards, and parallelled the depositional gradient as opposed to measures of food inputs and hydrodynamic regime. High environmental heterogeneity was observed during peak precipitation. The total number of species increased seawards and from August (122 species) to May (170 species). Maximum abundance also increased from August (4953 m-2) to May (10,220 individuals m-2), irrespective of distance from river mouth. Species belonging to different functional groups, as to recolonization, feeding, motility and substrate preferences, coexisted at all times indicating high functional diversity. Non-parametric multivariate regression showed that at times of low, rising and falling precipitation 78-81% of community variation was explained by environmental variables, indicating that macrofauna distribution and species composition respond to food inputs and sediment characteristics. During peak land runoff the community-environment relationship weakened (57% of the variability explained). The diversity of functional traits of the most abundant species indicates that the macrofauna community can absorb the impact of increased turbidity, sedimentation and current-driven dispersion. The study offers baseline information for the integrated coastal zone management in microtidal areas

Microphytobenthos and benthic macroalgae determine sediment organic matter composition in shallow photic sediments

NARCIS (Netherlands)

Hardison, A.K.; Canuel, E.A/; Anderson, I.C.; Tobias, C.R.; Veuger, B.; Waters, M.N.

2013-01-01

Microphytobenthos and benthic macroalgae play an important role in system metabolism within shallow coastal bays. However, their independent and interactive influences on sediment organic matter (SOM) are not well understood. We investigated the influence of macroalgae and microphytobenthos on SOM

Biodiversity of Macrofauna Associated with Sponges across Ecological Gradients in the Central Red Sea

KAUST Repository

Kandler, Nora

2015-01-01

Between 33 and 91 percent of marine species are currently undescribed, with the majority occurring in tropical and offshore environments. Sponges act as important microhabitats and promote biodiversity by harboring a wide variety of macrofauna

Caracterización de la meso y macrofauna edáfica en sistemas de cultivo del Sudeste Bonaerense Characterization of the meso and macrofauna of a Southeastern Buenos Aires province soil under different cropping systems

Directory of Open Access Journals (Sweden)

Antonio H Gizzi

2009-06-01

Full Text Available Los objetivos de este estudio fueron: i. determinar la composición taxonómica y la abundancia relativa de la meso y macrofauna y de sus grupos tróficos en suelos del sudeste de la provincia de Buenos Aires, ii. evaluar la densidad de los organismos que integran dichas comunidades y iii. estudiar el efecto de los sistemas de cultivo (combinación entre sistema de labranza y rotación y la fertilización sobre la meso y macrofauna. Se utilizaron cuatro sistemas de cultivo: LC50 [(50% pastura - 50% agricultura bajo labranza convencional (LC], SD50 [(50% pastura - 50% agricultura bajo siembra directa (SD], LC75 (25% pastura - 75% agricultura bajo LC, SD75 (25% pastura - 75% agricultura bajo SD y cuatro dosis de fertilización nitrogenada (0, 60, 120 y 180 kg de N ha-1. En el año 2000, en LC50 y en SD50 se sembró una pastura (P, la que en 2001 tenía un año de implantada. En el 2000, en LC75 y en SD75 se sembró maíz y en el 2001, soja. Dentro de la mesofauna, la mayoría de los individuos fueron enquitreidos, que en el primer año no presentaron diferencias entre LC y SD, mientras que en el segundo, los mayores porcentajes se observaron en P cuando ésta tenía más de un año de implantada. En la macrofauna predominaron oligoquetos megadrilos, isópodos y miriápodos y en P en ambos años los isópodos y miriápodos fueron dominantes. En el primer año, las densidades de la meso y macrofauna no mostraron diferencias significativas (p>0,003 entre sistemas de cultivo, sin embargo, fueron mayores en los cultivos bajo SD. En el segundo año, las densidades fueron significativamente mayores (p0,003 entre los sistemas de cultivo y las dosis de fertilización. A pesar de no haberse observado diferencias significativas (p>0,003 entre los sistemas en el primer año, los cuatro grupos fueron más abundantes en P y SD que en LC. En el segundo año, los detritívoros, los predadores y los omnívoros fueron significativamente más abundantes en P que en

A Comparison of Lignin, Macroalgae, Wood and Straw Fast Pyrolysis

DEFF Research Database (Denmark)

Trinh, Ngoc Trung; Jensen, Peter Arendt; Dam-Johansen, Kim

2013-01-01

these biomasses. The fast pyrolysis of macroalgae showed a promising result with a bio-oil yield of 65 wt% dry ash free basis (daf) and 76 % energy recovery in the bio-oil while the lignin fast pyrolysis provides a bio-oil yield of 47 wt% daf and energy recovery in bio-oil of 45 %. The physiochemical properties...... of the bio-oils were characterized with respect to higher heating value (HHV), molecular mass distribution, viscosity, pH, density, thermal behaviors, elemental concentrations, phase separation and aging. The lignin and macroalgae oil properties were different compared to those of the wood and straw oils......A fast pyrolysis study on lignin and macroalgae (non-conventional biomass) and wood and straw (conventional biomass) were carried out in a pyrolysis centrifugal reactor at pyrolysis temperature of 550 ºC. The product distributions and energy recoveries were measured and compared among...

Long-term (1998 vs. 2010) large-scale comparison of soft-bottom benthic macrofauna composition in the Gulf of Lions, NW Mediterranean Sea

Science.gov (United States)

Bonifácio, Paulo; Grémare, Antoine; Gauthier, Olivier; Romero-Ramirez, Alicia; Bichon, Sabrina; Amouroux, Jean-Michel; Labrune, Céline

2018-01-01

We achieved a long term (i.e., 1998 vs. 2010) large scale (i.e., whole Gulf of Lions) study of benthic macrofauna composition in the Gulf of Lions based on the resampling of 91 stations located along 21 inshore-offshore transects. Results show that the 3 main benthic communities identified in 1998 were still present in 2010 although their composition changed. Using only year and station of sampling we found a significant space-time interaction explaining changes in macrofaunal community composition, and, in this study, stations differ primarily in terms of depth and distance to the Rhône river mouth. Temporal changes in benthic macrofauna composition were clearly most important at shallow stations (i.e., in the Littoral Fine Sand community) than at deep ones (i.e., Terrigenous Coastal Mud community). These results are in good agreement with the current paradigm according to which climatic oscillations such as NAO (North Atlantic Oscillation) and WeMO (Western Mediterranean Oscillation) are indirectly (i.e., through changes in the frequency of occurrence and the intensity of storms) controlling benthic macrofauna composition in the Gulf of Lions. This hypothesis is further supported by a meta-analysis of changes in the average and maximal yearly abundances of the polychaete Ditrupa arietina. At last, the spatial modelling of 1998 and 2010 benthic macrofauna compositions both suggested a significant effect of Rhône River inputs on the spatial distribution of benthic macrofauna in the Gulf of Lions.

Potential of macroalgae for biodiesel production: Screening and evaluation studies.

Science.gov (United States)

Abomohra, Abd El-Fatah; El-Naggar, Amal Hamed; Baeshen, Areej Ali

2018-02-01

Nowadays, biofuel production is a fast expanding industry and is facing a growing dilemma about a feedstock source capable of keeping up with demand. Recently, macroalgae have been attracting a wide attention as a source for biofuel. In the present study, ten macroalgae were collected and screened as biodiesel feedstocks. As a result of their high biomass production and relatively high lipid content, Ulva lactuca, Padina boryana and Ulva intestinalis showed the highest significant lipids and fatty acid methyl esters (FAMEs) areal productivities among the studied species. Saturated fatty acids (SAFs) showed insignificant differences in the selected species, with noticeably significant higher polyunsaturated fatty acids (PUFAs) content in U. lactuca by 4.2 and 3 times, with respect to P. boryana and U. intestinalis, respectively. The recorded increase in PUFAs was attributed to higher content of C16:4n-3, C18:3n-3 and C18:4n-3. By lipid fractionation, P. boryana showed significant higher concentration of neutral lipids (37.7 mg g -1 CDW, representing 46.7% of total fatty acids) in comparison to U. lactuca and U. intestinalis, which showed 16% and 17% lower neutral lipid fractions, respectively. In addition, biodiesel characteristics of the studied macroalgae complied with that of international standards. Furthermore, oil-free residual biomass can be readily converted into fermentable sugars or biogas due to its high carbohydrates content, which adds to the economics of macroalgae as biofuel feedstock. In conclusion, the present study confirmed that macroalgae represent an attractive alternative renewable feedstock for biodiesel and other biofuels. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Macroalgae and macrozoobenthos of the Pčinja river

Directory of Open Access Journals (Sweden)

Simić Vladica M.

2003-01-01

Full Text Available During autumn and spring periods of 1998, 1999 and 2000, 4 taxa of macroalgae (divisions of Cyanophyta, Rhodophyta, Chrysophyta and Chlorophyta and 78 taxa of macrozoobenthos were found in 10 localities of Pčinja River, in a part of its watercourse through Serbia. Macroalga Cladophora glomerata was the most numerous among representatives. The find of red alga Lemanea sp. which was recorded for the first time at this biotope in Serbia, is significant. From representatives of macrozoobenthos the greatest number of species was found in the groups of Epheromeroptera, Trichoptera and larvae of Diptera. Majority of species of macrozoobenthos have wide geographic distribution, and in relation to ecological factors they are mainly eurivalent forms.

Comparative Studies on the Carbohydrate Composition of Marine Macroalgae: Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Mack, R. W.

1985-01-01

The purpose of this subcontract is to evaluate carbohydrates from macroalgae common to the Gulf of Mexico. Information from these analyses will be used to provide an indication of the feasibility of fermenting macroalgae to ethanol. Knowledge of the carbohydrates will allow for assessment of required pretreatments and utilization efficiencies in converting algal feedstocks to ethanol.

Temporal variation of sandy beach macrofauna at two sites with distinct environmental conditions on Cassino Beach, extreme southern Brazil

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Pedro de Sá Rodrigues da Silva

2008-12-01

Full Text Available Temporal variations of the macrofauna of sandy beaches have been related to variations in the beach morphodynamics and also to the population dynamics of dominant species. The aim of this article is to describe the temporal variation of the intertidal macrofauna at two sites with distinct environmental condition on Cassino Beach, extreme southern Brazil. At each site three transect lines 50 m apart were defined perpendicular to the shore line, from which samples were collected monthly in triplicate at 4 intertidal levels (10 m apart from June 2004 to May 2005. During winter a generally low density was observed, due to the absence of recruitments and to the mud deposition, which occurred just before sampling (in April 2004, and to low intensity stranding events. Spring witnessed a population explosion of Scolelepis gaucha, a migration of Mesodesma mactroides adults from the subtidal zone, and a strong stranding event. In the summer, recruitment of M. mactroides, Donax hanleyanus and Emerita brasiliensis was observed. Fall was characterized by low densities, except for D. hanleyanus recruitment. The macrofauna at both sites showed a striking seasonal variation in density and diversity, perhaps attributable to the recruitment of numerically dominant species and physical disturbances (stranding and mud deposition.Variações sazonais da macrofauna bentônica de praias arenosas têm sido relacionadas com variações da morfodinâmica da praia e também aos recrutamentos das espécies dominantes. Este trabalho objetiva avaliar a variabilidade temporal da macrofauna da zona entremarés de dois locais com distintas características ambientais na praia do Cassino, extremo sul do Brasil. Em cada local foram demarcadas três transversais (separadas por 50m perpendiculares à linha de água, nas quais amostras foram coletadas em triplicata em 4 níveis entremarés (separados por 10 m, entre junho/2004 e maio/2005. Durante o inverno ocorreram baixas

Eelgrass re-establishment in shallow estuaries is affected by drifting macroalgae

DEFF Research Database (Denmark)

Canal-Verges, Paula; Potthoff, M.; Hansen, F. T.

2014-01-01

surface sediment. Furthermore, drifting macroalgae ballistically damage eelgrass beds and increase seedling mortality. The frequency and impact of drifting macroalgae in Odense Fjord was evaluated with an agent-based model. The aims of this model were to understand and predict the mobility...... resuspension in bare bottoms and on rooted vegetation due to ballistic impacts in areas affected by algae drift. (C) 2013 Elsevier B.V. All rights reserved....

Chlorophyta and Rhodophyta macroalgae: a source of health promoting phytochemicals.

Science.gov (United States)

Santos, Sonia A O; Vilela, Carla; Freire, Carmen S R; Abreu, Maria H; Rocha, Silvia M; Silvestre, Armando J D

2015-09-15

A detailed study of the lipophilic composition of Codium tomentosum, Ulva lactuca, Gracilaria vermiculophylla and Chondrus crispus macroalgae cultivated in the Portuguese coast was carried out by gas chromatography-mass spectrometry before and after alkaline hydrolysis. Their long-chain aliphatic alcohols and monoglycerides compositions are reported for the first time. Additionally, other new compounds were also identified: phytol and neophytadiene in C. tomentosum, U. lactuca and G. vermiculophylla and stigmasterol, α-tocopherol and 24-methylenecholesterol in C. tomentosum. The lipophilic fraction of the studied macroalgae are mainly constituted by fatty acids (110.1-1030.5mgkg(-1) of dry material) and sterols (14.8-1309.1mgkg(-1) of dry material). C. tomentosum showed to be a valuable source of stigmasterol (1229.0mgkg(-1) of dry material) and α-tocopherol (21.8mgkg(-1) of dry material). These results are a relevant contribution for the valorisation of these macroalgae species as sources of valuable phytochemicals. Copyright © 2015 Elsevier Ltd. All rights reserved.

Trace element seasonality in marine macroalgae of different functional-form groups.

Science.gov (United States)

Malea, Paraskevi; Chatziapostolou, Anastasia; Kevrekidis, Theodoros

2015-02-01

Novel information on the seasonality of element accumulation in seaweeds is provided. Seasonal patterns of As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Se, Sr, U, V and Zn concentrations in macroalgae belonging to different functional-form groups (Ulva intestinalis, Ulva rigida, Codium fragile, Gracilaria gracilis) from the Thessaloniki Gulf, Aegean Sea were determined and compared. Uni- and multivariate data analyses were applied. Element concentrations generally decreased during spring and/or summer, probably due to the growth effect, but a reverse trend, particularly in Ulva species, was also observed. Most elements (Cd, Co, Cr, Cu, Mo, Ni, Pb, Sr) in Ulva species displayed a comparatively low monthly variability, indicating that the extent of seasonal variation is closely related to thallus morphology and growth strategy. In particular, these data suggest that Cd, Co, Cr, Cu, Mo, Ni, Pb and Sr contents in fast-growing, sheet-like macroalgae are less influenced by the season, compared to their contents in coarsely-branched and thick-leathery macroalgae; therefore, sheet-like macroalgae may be more appropriate to be used in biomonitoring of coastal waters. The data presented could be utilized in the development of biomonitoring programmes for the protection of coastal environments. Copyright © 2014 Elsevier Ltd. All rights reserved.

Macroalgas submareales de la bahía de Todos Santos, Baja California, México Submareal macroalgae of the Todos Santos Bay, Baja California, Mexico

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Raúl Aguilar-Rosas

2010-12-01

Full Text Available Con el fin de identificar y caracterizar la composición de especies de la zona submareal de la bahía de Todos Santos, Baja California, México; se realizaron muestreos de macroalgas marinas bentónicas en 7 sitios durante 1995-2000. Como resultado de 25 buceos Scuba entre 3 y 33 m de profundidad se encontraron 150 especies de macroalgas para el área de estudio; 10 son Chlorophyta, 26 Phaeophyta y 114 Rhodophyta. Del total, 47 son registros nuevos para el área de estudio y 2 de éstos, Faucheocolax attenuata Setchell y Minium parvum R.L. Moe, son nuevos para la flora marina del Pacífico de México. Se incluye una revisión de las investigaciones en las que se han considerado las macroalgas presentes en la bahía de Todos Santos y una discusión sobre la composición de las especies encontradas, su distribución vertical y reproducción, así como sobre las especies epífitas y parásitas del área.In order to identify and characterize the species composition of the subtidal zone of the Todos Santos Bay, Baja California, Mexico, benthic marine macroalgae were sampled at 7 sites from 1995 to 2000. As a result of 25 scuba at derds for the study area, of which Faucheocolax attenuata Setchell and R.L Moe Minium parvum are new to the marine flora of Pacific Mexico. We include a research that consider the macroalpths between 3 and 33 m we found a total of 150 species of macroalgae for the study area, of which 10 are Chlorophyta, 26 Phaeophyta and 114 Rhodophyta; 47 species represent new recogae in the Todos Santos Bay and a discussion on the composition of species found, its vertical distribution and reproduction, particularly the species epiphytes and parasites present in the study area.

Macroalgae Analysis A National GIS-based Analysis of Macroalgae Production Potential Summary Report and Project Plan

Energy Technology Data Exchange (ETDEWEB)

Roesijadi, Guritno; Coleman, Andre M.; Judd, Chaeli; Van Cleve, Frances B.; Thom, Ronald M.; Buenau, Kate E.; Tagestad, Jerry D.; Wigmosta, Mark S.; Ward, Jeffrey A.

2011-12-01

The overall project objective is to conduct a strategic analysis to assess the state of macroalgae as a feedstock for biofuels production. The objective in FY11 is to develop a multi-year systematic national assessment to evaluate the U.S. potential for macroalgae production using a GIS-based assessment tool and biophysical growth model developed as part of these activities. The initial model development for both resource assessment and constraints was completed and applied to the demonstration areas. The model for macroalgal growth was extended to the EEZ off the East and West Coasts of the United States, and a plan to merge the findings for an initial composite assessment was developed. In parallel, an assessment of land-based, port, and offshore infrastructure needs based on published and grey literature was conducted. Major information gaps and challenges encountered during this analysis were identified. Also conducted was an analysis of the type of local, state, and federal requirements that pertain to permitting land-based facilities and nearshore/offshore culture operations

Distinctly variable mudscapes: Distribution gradients of intertidal macrofauna across the Dutch Wadden Sea

NARCIS (Netherlands)

Compton, T.J.; Holthuijsen, S.; Koolhaas, A.; Dekinga, A.; ten Horn, J.; Smith, J.; Galama, Y.; Brugge, M.; van der Wal, D.; van der Meer, J.; van der Veer, H.W.; Piersma, T.

2013-01-01

The Wadden Sea is a shallow coastal region, with a large area of sedimentary tidal flats that extends from The Netherlands to Denmark and has been declared a site of international importance in the Dutch and German parts (Ramsar status and UNESCO World Heritage Site). Benthic macrofauna are central

Environmental features and macrofauna of Kahana Estuary, Oahu, Hawaii

Science.gov (United States)

Maciolek, J.A.; Timbol, A.S.

1981-01-01

Lack of ecological information on Hawaiian estuaries prompted an intensive 2-year study of a small (5.7 ha) stream-mouth estuary on windward Oahu. Water quality and macrofauna were sampled weekly at seven stations. The water mass was strongly stratified vertically except during freshets. Average values for water column temperature and bottom salinity were 23.2°C and 12‰ at the head to 28.3°C and 28‰ at the mouth. Dissolved oxygen saturation in the water column varied from about 50% at night to 140% in the afternoon. Usually, bottom waters were 3–6°C warmer than surface waters and sometimes showed severe oxygen depletion.Macrofauna, collected primarily by seining, consisted mainly of decapod crustaceans (four species of crabs, seven species of shrimps) and fishes (24 species). Other typical estuarine taxons (mollusks, barnacles, polychaetes) were scarce or absent. Diversity increased seaward from 14 species near the estuary head to 29 species near the mouth. Three species of crustaceans and six of fishes were captured at all stations. Most abundant were the native prawn, Macrobrachium grandimanus, and mullet, Mugil cephalus. Perennially resident adults occurred among crustaceans and gobioid fishes; most other fishes were present as juveniles and sporadic adults. Comparisons with other data suggest that more than 50 species of native fishes may occur in Hawaiian estuaries, and that estuarine macrofaunal diversity on oceanic islands is much lower than on continents at similar latitudes.

EVALUACIÓN DE LA MACROFAUNA DEL SUELO EN SOLANUM TUBEROSUM (SOLANALES: SOLANACEAE) CON SISTEMAS DE LABRANZA TRADICIONAL Y MÍNIMA

OpenAIRE

Botina G., Bibiana; Velásquez I., ángel; Bacca, Tito; Castillo F., Jesús; Dias, Lucimar G.

2012-01-01

El objetivo de esta investigación fue evaluar la diversidad, abundancia y biomasa de la macrofauna en cuatro diferentes usos del suelo; cultivo de papa con labranza mínima, cultivo de papa con labranza tradicional, suelo desnudo y una pradera de kikuyo. Para evaluar la fauna fue utilizada la metodología del programa Tropical Soil Biology and Fertility (TSBF). La macrofauna del suelo fue identificada hasta nivel de orden y familia. La mayor abundancia y diversidad de macroinvertebrados fue enc...

Comparative study on metal biosorption by two macroalgae in saline waters: single and ternary systems.

Science.gov (United States)

Figueira, Paula; Henriques, Bruno; Teixeira, Ana; Lopes, Cláudia B; Reis, Ana T; Monteiro, Rui J R; Duarte, A C; Pardal, M A; Pereira, E

2016-06-01

The biosorption capability of two marine macroalgae (green Ulva lactuca and brown Fucus vesiculosus) was evaluated in the removal of toxic metals (Hg, Cd and Pb) from saline waters, under realistic conditions. Results showed that, independently of the contamination scenario tested, both macroalgae have a remarkable capacity to biosorb Hg and Pb. In single-contaminant systems, by using only c.a. 500 mg of non-pre-treated algae biomass (size macroalgae exhibited a similar selectivity toward the target metals: Hg > Pb> > Cd, although Pb removal by U. lactuca was more inhibited than that achieved by F. vesiculosus. Under the experimental conditions used, none of the macroalgae was effective to remove Cd (maximum removal of 20 %). In all cases, the kinetics of biosorption was mathematically described with success. Globally, it became clear that the studied macroalgae may be part of simple, efficient, and cost-effective water treatment technologies. Nevertheless, Fucus vesiculosus has greater potential, since it always presented higher initial sorption rates and higher removal efficiencies.

Apparent characteristics and taxonomic study of macroalgae in Pattani Bay

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Naruemol Pianthumdee

2007-07-01

Full Text Available 2A survey on macroalgae in Pattani Bay was carried out to build up a database resource for the management of algae in the area. From February 2004 to March 2005, samples of macroalgae from 10 sites were randomly collected monthly. Macroalgae were found at 4 sites in the north of the bay, namely Laem Tachi, Lighthouse, Ban Bu Di and Ban Ta Lo Samilae; 3 sites in the east, namely Ban Da To, the Yaring River Mouth and Ban Bang Pu and only one site in the south at Ban Tanyong Lu Lo. Twelve species of 3 divisions of macroalgae were detected. They were Division Cyanophyta, Lyngbya majuscula (Dillwyn Harvey ex Gomont; Division Chlorophyta; Ulva intestinalis Linnaeus, U. pertusa Kjellman and U. reticulata Forsskal, Rhizoclonium riparium (Roth Harvey, R. tortuosum Kutzing, Chaetomorpha crassa (C. Agardh Kutzing and Cladophora sp.; and Division Rhodophyta, namely Gracilaria tenuistipitata Chang et Xia, G. fisheri (Xia et Abbott Abbott, Zhang et Xia, Hypnea spinella (C. Agardh Kutzing and Acanthophora spicifera (Vahl B∅rgesen. Among them, four species were new recordings at Pattani Bay: Lyngbya majuscula, Rhizoclonium riparium, R. tortuosum and Acanthophora spicifera. Most of these seaweeds were found at the east sites in the dry season from February to September 2004 and from January to March 2005. Only a few species could be found in the wet season from November to December 2004.

Soil fertility management: Impacts on soil macrofauna, soil aggregation and soil organic matter allocation.

NARCIS (Netherlands)

Ayuke, F.O.; Brussaard, L.; Vanlauwe, B.; Six, J.; Lelei, D.K.; Kibunja, C.N.; Pulleman, M.M.

2011-01-01

Maintenance of soil organic matter through integrated soil fertility management is important for soil quality and agricultural productivity, and for the persistence of soil faunal diversity and biomass. Little is known about the interactive effects of soil fertility management and soil macrofauna

Diversity of pigmented Gram-positive bacteria associated with marine macroalgae from Antarctica.

Science.gov (United States)

Leiva, Sergio; Alvarado, Pamela; Huang, Ying; Wang, Jian; Garrido, Ignacio

2015-12-01

Little is known about the diversity and roles of Gram-positive and pigmented bacteria in Antarctic environments, especially those associated with marine macroorganisms. This work is the first study about the diversity and antimicrobial activity of culturable pigmented Gram-positive bacteria associated with marine Antarctic macroalgae. A total of 31 pigmented Gram-positive strains were isolated from the surface of six species of macroalgae collected in the King George Island, South Shetland Islands. On the basis of 16S rRNA gene sequence similarities ≥99%, 18 phylotypes were defined, which were clustered into 11 genera of Actinobacteria (Agrococcus, Arthrobacter, Brachybacterium, Citricoccus, Kocuria, Labedella, Microbacterium, Micrococcus, Rhodococcus, Salinibacterium and Sanguibacter) and one genus of the Firmicutes (Staphylococcus). It was found that five isolates displayed antimicrobial activity against a set of macroalgae-associated bacteria. The active isolates were phylogenetically related to Agrococcus baldri, Brachybacterium rhamnosum, Citricoccus zhacaiensis and Kocuria palustris. The results indicate that a diverse community of pigmented Gram-positive bacteria is associated with Antartic macroalgae and suggest its potential as a promising source of antimicrobial and pigmented natural compounds. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Optimum Fermentation Process for Red Macroalgae Gelidium latifolium and Gracillaria verrucosa

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Mujizat Kawaroe

2015-12-01

Full Text Available Red macroalgae have the potential to be processed into bioethanol due to their high carbohydrate and low lignin content. Gelidium latifolium and Gracilaria verrucosa are red macroalgae commonly found in Indonesian seas. Sometimes an over-supply of red macroalgae is rejected by the food industry, which opens up opportunities for others uses, e.g. for producing bioethanol. The objectives of this research were to analyze the influence of sulfuric acid concentration on hydrolysis of G. latifolium and G. verrucosa and to calculate the optimum fermentation process to produce bioethanol. G. latifolium and G. verrucosa were hydrolyzed using H2SO4 at concentrations of 1%, 2%, 3%, and 4%, at a temperature of 121 °C and a pressure of 1.5 bar for 45 minutes. The process of fermentation was done using Saccharomyces cerevisiae in anaerobic conditions for 4, 5, 6 and 7 days. The results show that the optimum H2SO4 concentrations to hydrolyze G. latifolium and G. verrucosa were 1% and 2% respectively. The number of S. cerevisiae cells in hydrolysate G. latifolium and G. verrucosa increased in the third adaptation. S. cerevisiae can convert sugar from G. latifolium and G. verrucosa into bioethanol through fermentation. The highest bioethanol yields were achieved on days five and six. Therefore, red macroalgae can be seen as a potential raw material for bioethanol production.

Protective role of marine macroalgae extracts against STZ induced diabetic rats

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Marine macroalgae

2017-12-01

Full Text Available Objective: To study the anti-diabetic activity of marine macroalgae extracts (n = 31, purification and characterization of sulphated galactopyran (SGP from Gracilaria opuntia (FM4 in diabetic rats. Methods: The animals were separated into groups and STZ (55 mg/kg body weight was used to induce diabetics. Glucose, HbA1c, insulin, C-peptide levels and in vivo antioxidant levels were estimated and histopathological studies were done in STZ-induced diabetic and marine macroalgae treated rats. Results: Based on glucose and HbA1c levels and in vivo antioxidant levels, among the 31 marine macroalgae extracts, FM4 has showed high anti-diabetic activity. Hence, FM4 was purified and characterized by 1H-NMR spectra and FT-IR as sulphated galactopyran. During the survival analysis, SGP at dose of 100 mg/kg showed significant (P < 0.05 survival rate and elevations in C-peptide and insulin levels. The histopathological modulations of SGP were observed in diabetic rat tissues such as liver, kidney and brain. Hence obtained results reveal that SGP treated diabetic rats has significant changes in C-peptide and insulin levels which regulates the blood glucose levels and recovered the histopathological changes. Conclusions: Marine macroalgae have significant anti-diabetic activity. Hence, they could be used as nutraceutical supplement or natural green remedy against diabetes mellitus.

Selecting reliable and robust freshwater macroalgae for biomass applications.

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Rebecca J Lawton

Full Text Available Intensive cultivation of freshwater macroalgae is likely to increase with the development of an algal biofuels industry and algal bioremediation. However, target freshwater macroalgae species suitable for large-scale intensive cultivation have not yet been identified. Therefore, as a first step to identifying target species, we compared the productivity, growth and biochemical composition of three species representative of key freshwater macroalgae genera across a range of cultivation conditions. We then selected a primary target species and assessed its competitive ability against other species over a range of stocking densities. Oedogonium had the highest productivity (8.0 g ash free dry weight m⁻² day⁻¹, lowest ash content (3-8%, lowest water content (fresh weigh: dry weight ratio of 3.4, highest carbon content (45% and highest bioenergy potential (higher heating value 20 MJ/kg compared to Cladophora and Spirogyra. The higher productivity of Oedogonium relative to Cladophora and Spirogyra was consistent when algae were cultured with and without the addition of CO₂ across three aeration treatments. Therefore, Oedogonium was selected as our primary target species. The competitive ability of Oedogonium was assessed by growing it in bi-cultures and polycultures with Cladophora and Spirogyra over a range of stocking densities. Cultures were initially stocked with equal proportions of each species, but after three weeks of growth the proportion of Oedogonium had increased to at least 96% (±7 S.E. in Oedogonium-Spirogyra bi-cultures, 86% (±16 S.E. in Oedogonium-Cladophora bi-cultures and 82% (±18 S.E. in polycultures. The high productivity, bioenergy potential and competitive dominance of Oedogonium make this species an ideal freshwater macroalgal target for large-scale production and a valuable biomass source for bioenergy applications. These results demonstrate that freshwater macroalgae are thus far an under-utilised feedstock with

Fast pyrolysis of lignin, macroalgae and sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Trinh, N.T.

2013-04-15

Non-conventional biomass feedstock may also be applicable for fast pyrolysis processes. Among the forms of non-conventional biomasses, macroalgae, lignin (industrial residue) and sewage sludge may be attractive materials due to their low price, non-competitiveness with food crops and the possible utilization of solid wastes. Besides, a fast pyrolysis process can be used as a process to densify the biomass and produce bioslurry, a mixture of bio-oil and pyrolytic char. The bioslurry is found to be a possible feedstock for pressurized gasification plants. Thus, the aims of this project are to investigate fast pyrolysis properties of lignin, sewage sludge and macroalgae on a lab scale PCR and characterize their bio-oil properties. Bioslurry properties with respect to use as a feedstock for pressurized gasification is also investigated. Lignin and sewage sludge PCR pyrolysis provided bio-oil yields of 47 and 54 wt% daf, and oil energy recovery of 45 and 50 %, respectively. While the macroalgae PCR pyrolysis showed promising results with an organic oil yield of 65 wt% daf and an oil energy recovery of 76 %. The HHV of the lignin, sewage sludge and macroalgae oils were 29.7, 25.7 and 25.5 MJ/kg db respectively, and that are higher than that of typical bioiv oil from conventional biomasses (23-24 MJ/kg db). Almost all metals feedstock contents were contained in the chars at temperatures of 550 - 575 deg. C for lignin, sewage sludge and macroalgae PCR pyrolysis. Due to high feedstock nitrogen and sulfur contents, also a high level of nitrogen and sulfur of macroalgae and sewage sludge oils were observed compared to conventional bio-oil and this may limit their further industrial applications. The lignin char had a high proportion of small size particles, a HHV of 21 MJ/kg db and were almost free of chloride and sulfur, thus it is considered as a promising fuel for gasification or combustion; whereas macroalgae and sewage sludge chars containing high amounts of

Radionuclide accumulation in green and brown macroalgae at the Bulgarian Black Sea coast

International Nuclear Information System (INIS)

Strezov, A.; Nonova, T.

2005-01-01

The concentration of technogenic and natural radionuclides were measured in brown and green macroalgae from the Bulgarian Black Sea coast for the period 1996 and 2003 using low-level gamma spectroscopy. Mean values and concentration range for the studied species enables the comparison of the nuclide content in macroalgae showing that brown algae accumulate the studied radionuclides to a higher extent. (author)

A deep sea community at the Kebrit brine pool in the Red Sea

KAUST Repository

Vestheim, Hege

2015-02-26

Approximately 25 deep sea brine pools occur along the mid axis of the Red Sea. These hypersaline, anoxic, and acidic environments have previously been reported to host diverse microbial communities. We visited the Kebrit brine pool in April 2013 and found macrofauna present just above the brine–seawater interface (~1465 m). In particular, inactive sulfur chimneys had associated epifauna of sea anemones, sabellid type polychaetes, and hydroids, and infauna consisting of capitellid polychaetes, gastropods of the genus Laeviphitus (fam. Elachisinidae), and top snails of the family Cocculinidae. The deep Red Sea generally is regarded as extremely poor in benthos. We hypothesize that the periphery along the Kebrit holds increased biomass and biodiversity that are sustained by prokaryotes associated with the brine pool or co-occurring seeps.

Biomass and Habitat Characteristics of Epiphytic Macroalgae in the Sibuti Mangroves, Sarawak, Malaysia.

Science.gov (United States)

Isa, Hasmidah Md; Kamal, Abu Hena Mustafa; Idris, Mohd Hanafi; Rosli, Zamri; Ismail, Johan

2017-01-01

Mangroves support diverse macroalgal assemblages as epibionts on their roots and tree trunks. These algae provide nutrients to the primary consumers in the aquatic food web and have been reported to be substantial contributors to marine ecosystems. The species diversity, biomass, and habitat characteristics of mangrove macroalgae were investigated at three stations in the Sibuti mangrove estuary, Sarawak, Malaysia, from November 2012 to October 2013. Three groups of macroalgae were recorded and were found to be growing on mangrove prop roots, namely Rhodophyta ( Caloglossa ogasawaraensis , Caloglossa adhaerens , Caloglossa stipitata , Bostrychia anomala, and Hypnea sp.), Chlorophyta ( Chaetomorpha minima and Chaetomorpha sp.), and Phaeophyta ( Dictyota sp.). The biomass of macroalgae was not influenced ( p >0.05) by the season in this mangrove forest habitat. The macroalgal species Hypnea sp. contributed the highest biomass at both Station 1 (210.56 mg/cm 2 ) and Station 2 (141.72 mg/cm 2 ), while the highest biomass was contributed by B. anomala (185.89 mg/cm 2 ) at Station 3. This study shows that the species distribution and assemblages of mangrove macroalgae were influenced by environmental parameters such as water nutrients, dissolved solids, and salinity in the estuarine mangrove habitats of Sibuti, Sarawak.

Nitrous Oxide Production by Abundant Benthic Macrofauna

DEFF Research Database (Denmark)

Stief, Peter; Schramm, Andreas

of the short-term metabolic induction of gut denitrification is the preferential production of nitrous oxide rather than dinitrogen. On a large scale, gut denitrification in, for instance, Chironomus plumosus larvae can increase the overall nitrous oxide emission of lake sediment by a factor of eight. We...... screened more than 20 macrofauna species for nitrous oxide production and identified filter-feeders and deposit-feeders that occur ubiquitously and at high abundance (e.g., chironomids, ephemeropterans, snails, and mussels) as the most important emitters of nitrous oxide. In contrast, predatory species...... that do not ingest large quantities of microorganisms produced insignificant amounts of nitrous oxide. Ephemera danica, a very abundant mayfly larva, was monitored monthly in a nitrate-polluted stream. Nitrous oxide production by this filter-feeder was highly dependent on nitrate availability...

Efecto de la macroalga Caulerpa sertularioides en el desarrollo del camarón Penaeus californiensis (Decapoda: Peneidae

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Marco Antonio Porchas Cornejo

1999-09-01

Full Text Available El efecto de la macroalga Caulerpa sertularioides sobre el crecimiento, sobrevivencia y producción en cautiverio del camarón café Penaeus californiensis (Holmes, 1900 a temperaturas invernales (14 a 21°C se estudió en La Paz, B.C.S., México. Se utilizaron nueve unidades experimentales (Tres por el tratamiento consistiendo en tanques plásticos de150 l de capacidad. El crecimiento del camarón con la presencia directa de la macroalga fue de 3.98 ± 0.4 g después de 10 semanas de cultivo, la sobrevivencia fue del 100 % y el rendimiento de 36.24 ± 4.3 g. Estos resultados fueron significativamente más altos que los obtenidos en presencia indirecta, y en ausencia de la macroalga, los cuales no presentaron diferencias significativas entre sí. El crecimiento, sobrevivencia y producción en la presencia indirecta de la macroalga fueron de 0.73 ± 0.4 g, 75± 10% and 7.8 + 1.2 g respectivamente. En ausencia de la macroalga, se obtuvieron valores de 0.46 ± 0.4 g, 68.7 ± 12% y 5.6 ±1.1 g. La presencia directa de la macroalga tiene un efecto positivo y significativo en el desarrollo del camarón café en cautiverio.The effect of the macroalga Caulerpa sertularioides on the growth, survival and yield of captive yellowleg shrimp Penaeus californiensis (Holmes, 1900 at winter temperatures (14 to 21°C was studied at La Paz, B.C.S., México. Nine experimental units (three per treatment consisting in 150 l-fiberglass tanks were used. Shrimp growth with macroalgal presence was 3.98 ± 0.4 g after 10 weeks, survival was 100% and yield 36.24 ± 4.3 g. These results were better than those obtained with indirect presence, and absence of the macroalga, which were not different among themselves. Under indirect macroalgal presence growth, survival and yield were 0.73 ± 0.4 g, 75± 10% and 7.8 ± 1.2 g. Without macroalgae, corresponding values were 0.46 ± 0.4 g, 68.7 ± 12% and 5.6 ±1.1 g. Significant differences were found between "absence" and "indirect

Interaction strength between different grazers and macroalgae mediated by ocean acidification over warming gradients.

Science.gov (United States)

Sampaio, E; Rodil, I F; Vaz-Pinto, F; Fernández, A; Arenas, F

2017-04-01

Since the past century, rising CO 2 levels have led to global changes (ocean warming and acidification) with subsequent effects on marine ecosystems and organisms. Macroalgae-herbivore interactions have a main role in the regulation of marine community structure (top-down control). Gradients of warming prompt complex non-linear effects on organism metabolism, cascading into altered trophic interactions and community dynamics. However, not much is known on how will acidification and grazer assemblage composition shape these effects. Within this context, we aimed to assess the combined effects of warming gradients and acidification on macroalgae-herbivore interactions, using three cosmopolitan species, abundant in the Iberian Peninsula and closely associated in nature: the amphipod Melita palmata, the gastropod Gibbula umbilicalis, and the green macroalga Ulva rigida. Under two CO 2 treatments (ΔCO 2 ≃ 450 μatm) across a temperature gradient (13.5, 16.6, 19.9 and 22.1 °C), two mesocosm experiments were performed to assess grazer consumption rates and macroalgae-herbivore interaction, respectively. Warming (Experiment I and II) and acidification (Experiment II) prompted negative effects in grazer's survival and species-specific differences in consumption rates. M. palmata was shown to be the stronger grazer per biomass (but not per capita), and also the most affected by climate stressors. Macroalgae-herbivore interaction strength was markedly shaped by the temperature gradient, while simultaneous acidification lowered thermal optimal threshold. In the near future, warming and acidification are likely to strengthen top-down control, but further increases in disturbances may lead to bottom-up regulated communities. Finally, our results suggest that grazer assemblage composition may modulate future macroalgae-herbivore interactions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Review on toxicity testing with marine macroalgae and the need for method standardization--exemplified with copper and phenol.

Science.gov (United States)

Eklund, Britta T; Kautsky, Lena

2003-02-01

Toxic effects on macroalgae have been compiled. Eighty-two articles have been found in literature during 1959-2000. A total of 120 substances were investigated using 65 different macroalgae species. About one-third of the tested compounds were organic substances (33%), another third metal-organic substances (35%), and the last third were oils (14%), metals (8%), detergents (7.5%) and other inorganic chemicals (2.5%). Half of the substances were only tested once on a single species. Likewise, toxicity data has only been reported for one chemical tested on a single occasion for about half of the 65 species. Thus little is known about the toxic effects on marine macroalgae. The objectives of the previous studies undertaken varied and therefore the toxicity data was presented in numerous ways, e.g. using different exposure times, temperature, light intensity, light regime, salinity, and nutrients, which makes a direct comparison of the data difficult. This review also shows that many stages in the lifecycle of macroalgae are often more sensitive to toxic substances than other aquatic organisms. Consequently, tests using macroalgae may discover toxicity earlier, which would in turn also protect the fauna. If toxic compounds have a negative affect on the distribution and growth of structurally and functionally dominating macroalgae, there may indirectly be a large and harmful influence on the whole marine coastal ecosystem. For this reason tests on macroalgae should be included in control programs along the coasts.

Macrofauna associated with Saccorhiza polyschides (Lightfoot Batters 1902 holdfasts

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Susana Pereira

2014-06-01

Full Text Available Distribution patterns of species and the causes driving its distribution have always been central questions in ecology, as well as the mechanisms determining species composition and structure of biological assemblages. In the present work the distribution patterns of the macrofauna associated with Saccorhiza polyschides holdfasts along the western coast of Iberian Peninsula was studied. The aims of this work were to evaluate (i the role of Saccorhiza polyschides holdfasts as suitable habitat for littoral macrofauna, (ii the influence of latitude on the colonization patterns, and (iii to examine the processes determining these colonization patterns. This study took place at three different locations along the western coast of Iberian Peninsula, Ferrol (Galicia, northern Spain, Viana do Castelo (northern Portugal and Figueira da Foz (central Portugal. Sampling of macrofaunal organisms was held by scuba diving and eight samples were collected on the nearshore rocky subtidal zone of each site. All species were identified to the highest taxonomic level possible. Similarity analyses (Cluster and NMDS showed the separation of the sampling sites in two different groups: one corresponding to the northern limits of the study area (Ferrol and another corresponding to the two Portuguese sampling sites (Viana do Castelo and Figueira da Foz. The results showed that Saccorhiza polyschides provides a suitable habitat for 107 species, mainly small crustaceans like amphipods and molluscs. The inner species partitioning of samples suggests the additional influence of the exposure degree of each sampling area. The observed colonization patterns are consistent with habitats with high level of environmental stress, which could be related to the seasonal instability of holdfasts.

Biodiversity of Macrofauna Associated with Sponges across Ecological Gradients in the Central Red Sea

KAUST Repository

Kandler, Nora

2015-12-01

Between 33 and 91 percent of marine species are currently undescribed, with the majority occurring in tropical and offshore environments. Sponges act as important microhabitats and promote biodiversity by harboring a wide variety of macrofauna and microbiota, but little is known about the relationships between the sponges and their symbionts. This study uses DNA barcoding to examine the macrofaunal communities associated with sponges of the central Saudi Arabian Red Sea, a drastically understudied ecosystem with high biodiversity and endemism. In total, 185 epifaunal and infaunal operational taxonomic units (OTUs) were distinguished from the 1399 successfully-sequenced macrofauna individuals from 129 sponges representing seven sponge species, one of which (Stylissa carteri) was intensively studied. A significant difference was found in the macrofaunal community composition of Stylissa carteri along a cross-shelf gradient using relative OTU abundance (Bray-Curtis diversity index). The abundance of S. carteri also follows a cross-shelf gradient, increasing with proximity to shore. The difference in macrofaunal communities of several species of sponges at one location was found to be significant as well, using OTU presence (binary Jaccard diversity index). Four of the seven sponge species collected were dominated by a single annelid OTU, each unique to one sponge species. A fifth was dominated by four arthropod OTUs, all species-specific as well. Region-based diversity differences may be attributed to environmental factors such as reef morphology, water flow, and sedimentation, whereas species-based differences may be caused by sponge morphology, microbial abundances, and chemical defenses. As climate change and ocean acidification continue to modify coral reef ecosystems, understanding the ecology of sponges and their role as microhabitats may become more important. This thesis also includes a supplemental document in the form of a spreadsheet showing the number of

Antimicrobial activity of methanolic extracts of selected marine macroalgae against some pathogenic microorganisms

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Ehab Omer Abdalla

2016-05-01

Full Text Available Objective: To evaluate the antimicrobial activity of methanolic extracts of six marine macroalgae belonging to green algae (Chlorophyceae, brown algae (Phaeophyceae and the red algae (Rhodophyceae collected from the intertidal area of the Sudanese Red Sea coast near Port Sudan. Methods: Methanol was used for extracting the active principles of the algae and the disc diffusion method was performed to examine the activity and the minimum inhibitory concentration of the samples against four pathogenic bacteria and two fungi. Results: All tested algal extracts exhibited considerable bioactivity and inhibited the growth of all pathogenic microorganisms under investigation. The green alga Caulerpa racemosa produced the maximum inhibition zone (21 mm against Candida albicans while the red alga Laurencia papillosa showed low antimicrobial activity with the minimum inhibition zone of 10 mm against Pseudomonas aeruginosa. The tested algal extracts did not show any special antimicrobial influence on the selected microorganisms when they were considered as Grampositive and Gram-negative bacteria and fungi but the most efficient methanolic extracts in inhibiting microbial growth were those of green macroalgae followed by the brown and the red macroalgae respectively. Conclusions: The study demonstrated that the tested marine macroalgae from Sudanese Red Sea coast may represent a potential and alternative source for secondary metabolites with antimicrobial activity.

Stable nitrogen isotopes in coastal macroalgae: Geographic and anthropogenic variability

International Nuclear Information System (INIS)

Viana, Inés G.; Bode, Antonio

2013-01-01

Growing human population adds to the natural nitrogen loads to coastal waters. Both anthropogenic and natural nitrogen is readily incorporated in new biomass, and these different nitrogen sources may be traced by the measurement of the ratio of stable nitrogen isotopes (δ 15 N). In this study δ 15 N was determined in two species of macroalgae (Ascophyllum nodosum and Fucus vesiculosus), and in nitrate and ammonium to determine the relative importance of anthropogenic versus natural sources of nitrogen along the coast of NW Spain. Both algal species and nitrogen sources showed similar isotopic enrichment for a given site, but algal δ 15 N was not related to either inorganic nitrogen concentrations or δ 15 N in the water samples. The latter suggests that inorganic nitrogen inputs are variable and do not always leave an isotopic trace in macroalgae. However, a significant linear decrease in macroalgal δ 15 N along the coast is consistent with the differential effect of upwelling. Besides this geographic variability, the influence of anthropogenic nitrogen sources is evidenced by higher δ 15 N in macroalgae from rias and estuaries compared to those from open coastal areas and in areas with more than 15 × 10 3 inhabitants in the watershed. These results indicate that, in contrast with other studies, macroalgal δ 15 N is not simply related to either inorganic nitrogen concentrations or human population size but depends on other factors as the upwelling or the efficiency of local waste treatment systems. - Highlights: ► Anthropogenic versus upwelling nitrogen effect on macroalgal δ 15 N was studied. ► The influence of populations and upwelling has not been made before on macroalgal δ 15 N. ► Natural variability has not been taken into account in most biomonitoring studies. ► Upwelling explains most of the variability in δ 15 N in macroalgae

Radionuclide uptake in red macroalgae from the Bulgarian Black Sea coast

International Nuclear Information System (INIS)

Nonova, Tz.; Strezov, A.

2005-01-01

Technogenic and natural radionuclide content in red macroalgae (Ceramium rubrum, Corallina officinalis and Callithamnion corymbosum) from the Bulgarian Black Sea coast, collected in the period 1992-2003, was studied by low-level gamma-spectrometry. The data show that the nuclide concentrations depend on macroalgae species and coast locations. The highest nuclide content was measured in Ceramium rubrum species. The 137 Cs mean value is 9.8 Bq/kg, 19.6 Bq/kg for 226 Ra and 17 Bq/kg for 210 Pb. The radionuclide pollution is considerably small due to the absence of nuclear facilities along the Bulgarian Black Sea coast. (author)

Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water

OpenAIRE

Michael B. Ellison; Rocky de Nys; Nicholas A. Paul; David A. Roberts

2014-01-01

The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation...

Alien macroalgae in Denmark - a broad-scale national perspective

DEFF Research Database (Denmark)

Thomsen, Mads S.; Wernberg, Thomas; Stæhr, Peter Anton

2007-01-01

Most studies documenting the importance of alien macroalgae relative to native species are based on smaller-scale sampling programmes. Between 1989 and 2003, a Danish monitoring programme collected data on the percentage cover of macroalgae at more than 600 locations throughout the country. We...... examined this data set to estimate the relative abundance of alien species in the algal flora on large spatiotemporal scales, i.e. across depth ranges, regions and years. Of the 10 alien macroalgal species known to inhabit Danish coastal waters, nine were found in the survey. Most of the alien species were...... only present in low quantities (alien species, Sargassum muticum and Bonnemaisonia hamifera, constituted 2-7% of the assemblages, depending on depth, region and year. Sargassum muticum was abundant from 0 to 5 m in the northwestern region...

Alien macroalgae in Denmark - A broad-scale national perspective

DEFF Research Database (Denmark)

Thomsen, M. S.; Wernberg, T.; Stæhr, P.

2007-01-01

Most studies documenting the importance of alien macroalgae relative to native species are based on smaller-scale sampling programmes. Between 1989 and 2003, a Danish monitoring programme collected data on the percentage cover of macroalgae at more than 600 locations throughout the country. We...... examined this data set to estimate the relative abundance of alien species in the algal flora on large spatiotemporal scales, i.e. across depth ranges, regions and years. Of the 10 alien macroalgal species known to inhabit Danish coastal waters, nine were found in the survey. Most of the alien species were...... only present in low quantities (alien species, Sargassum muticum and Bonnemaisonia hamifera, constituted 2-7% of the assemblages, depending on depth, region and year. Sargassum muticum was abundant from 0 to 5 m in the northwestern region...

Potencial de cultivo da macroalga Kappaphycus alvarezii no litoral de Santa Catarina

OpenAIRE

Santos, Alex Alves dos

2014-01-01

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Aqüicultura, Florianópolis, 2014. Os cultivos da macroalga K. alvarezii em monocultivo ou integrados com moluscos (Crassostrea gigas e Perna perna) podem proporcionar benefícios ambientais e econômicos. Este trabalho avaliou o potencial de cultivo da macroalga Kappaphycus alvarezii no parque aquícola de Santa Catarina. O primeiro trabalho identificou a capacidade do parque e...

Spatial distribution of macroalgae along the shores of Kongsfjorden (West Spitsbergen using acoustic imaging

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Kruss Aleksandra

2017-06-01

Full Text Available The identification of macroalgal beds is a crucial component for the description of fjord ecosystems. Direct, biological sampling is still the most popular investigation technique but acoustic methods are becoming increasingly recognized as a very efficient tool for the assessment of benthic communities. In 2007 we carried out the first acoustic survey of the littoral areas in Kongsfjorden. A 2.68 km2 area comprised within a 12.40 km2 euphotic zone was mapped along the fjord’s coast using single- and multi-beam echosounders. The singlebeam echosounder (SBES proved to be a very efficient and reliable tool for macroalgae detection in Arctic conditions. The multibeam echosounder (MBES was very useful in extending the SBES survey range, even though it’s ability in discriminating benthic communities was limited. The final result of our investigation is a map of the macroalgae distribution around the fjord, showing 39% macroalgae coverage (1.09 km2 of investigated area between isobaths -0.70 m and -30 m. Zonation analysis showed that most of the studied macroalgae areas occur up to 15 m depth (93%. These results were confirmed by biological sampling and observation in key areas. The potential of acoustic imaging of macrophytes, and a proposed methodology for the processing of acoustic data, are presented in this paper along with preliminary studies on the acoustic reflectivity of macroalgae, also highlighting differences among species. These results can be applied to future monitoring of the evolution of kelp beds in different areas of the Arctic, and in the rest of the world.

Effects of marine and freshwater macroalgae on in vitro total gas and methane production.

Science.gov (United States)

Machado, Lorenna; Magnusson, Marie; Paul, Nicholas A; de Nys, Rocky; Tomkins, Nigel

2014-01-01

This study aimed to evaluate the effects of twenty species of tropical macroalgae on in vitro fermentation parameters, total gas production (TGP) and methane (CH4) production when incubated in rumen fluid from cattle fed a low quality roughage diet. Primary biochemical parameters of macroalgae were characterized and included proximate, elemental, and fatty acid (FAME) analysis. Macroalgae and the control, decorticated cottonseed meal (DCS), were incubated in vitro for 72 h, where gas production was continuously monitored. Post-fermentation parameters, including CH4 production, pH, ammonia, apparent organic matter degradability (OMd), and volatile fatty acid (VFA) concentrations were measured. All species of macroalgae had lower TGP and CH4 production than DCS. Dictyota and Asparagopsis had the strongest effects, inhibiting TGP by 53.2% and 61.8%, and CH4 production by 92.2% and 98.9% after 72 h, respectively. Both species also resulted in the lowest total VFA concentration, and the highest molar concentration of propionate among all species analysed, indicating that anaerobic fermentation was affected. Overall, there were no strong relationships between TGP or CH4 production and the >70 biochemical parameters analysed. However, zinc concentrations >0.10 g x kg(-1) may potentially interact with other biochemical components to influence TGP and CH4 production. The lack of relationship between the primary biochemistry of species and gas parameters suggests that significant decreases in TGP and CH4 production are associated with secondary metabolites produced by effective macroalgae. The most effective species, Asparagopsis, offers the most promising alternative for mitigation of enteric CH4 emissions.

Effects of marine and freshwater macroalgae on in vitro total gas and methane production.

Directory of Open Access Journals (Sweden)

Lorenna Machado

Full Text Available This study aimed to evaluate the effects of twenty species of tropical macroalgae on in vitro fermentation parameters, total gas production (TGP and methane (CH4 production when incubated in rumen fluid from cattle fed a low quality roughage diet. Primary biochemical parameters of macroalgae were characterized and included proximate, elemental, and fatty acid (FAME analysis. Macroalgae and the control, decorticated cottonseed meal (DCS, were incubated in vitro for 72 h, where gas production was continuously monitored. Post-fermentation parameters, including CH4 production, pH, ammonia, apparent organic matter degradability (OMd, and volatile fatty acid (VFA concentrations were measured. All species of macroalgae had lower TGP and CH4 production than DCS. Dictyota and Asparagopsis had the strongest effects, inhibiting TGP by 53.2% and 61.8%, and CH4 production by 92.2% and 98.9% after 72 h, respectively. Both species also resulted in the lowest total VFA concentration, and the highest molar concentration of propionate among all species analysed, indicating that anaerobic fermentation was affected. Overall, there were no strong relationships between TGP or CH4 production and the >70 biochemical parameters analysed. However, zinc concentrations >0.10 g x kg(-1 may potentially interact with other biochemical components to influence TGP and CH4 production. The lack of relationship between the primary biochemistry of species and gas parameters suggests that significant decreases in TGP and CH4 production are associated with secondary metabolites produced by effective macroalgae. The most effective species, Asparagopsis, offers the most promising alternative for mitigation of enteric CH4 emissions.

Pretreatment of macroalgae for volatile fatty acid production.

Science.gov (United States)

Pham, Thi Nhan; Um, Youngsoon; Yoon, Hyon Hee

2013-10-01

In this study, a novel method was proposed for the biological pretreatment of macroalgae (Laminaria japonica, Pachymeniopsis elliptica, and Enteromorpha crinita) for production of volatile fatty acid (VFA) by anaerobic fermentation. The amount of VFA produced from 40 g/L of L. japonica increased from 8.3 g/L (control) to 15.6 g/L when it was biologically pretreated with Vibrio harveyi. The biological treatment of L. japonica with Vibrio spp. was most effective likely due to the alginate lyase activity of Vibrio spp. However, a considerable effect was also observed after biological pretreatment of P. elliptica and E. crinita, which are red and green algae, respectively. Alkaline pretreatment of 40 g/L of L. japonica with 0.5 N NaOH resulted in an increase of VFA production to 12.2 g/L. These results indicate that VFA production from macroalgae can be significantly enhanced using the proposed biological pretreatments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Preference of the herbivorous marine teleost Siganus canaliculatus for different macroalgae

Science.gov (United States)

You, Cuihong; Zeng, Fangui; Wang, Shuqi; Li, Yuanyou

2014-06-01

The decomposition of a large amount of unexploited macroalgal resource along the coast of China often results in heavy environmental pollution. In order to pave a way of using macroalgae as the dietary ingredient of rabbitfish Siganus canaliculatus, one of a few farmed herbivorous marine teleosts in China, its preference (feeding selectivity) for different macroalgae was determined in this study. Seven seaweed species abundantly inhabiting the coast of east Guangdong Province were exposed simultaneously to rabbitfish juveniles in laboratory (multiple-choice feeding) with their content and absolute intake assayed. It was found that the most preferred algae were Ulva prolifera, Gracilaria lemaneiformis and Chaetomorpha linum, less preferred algae were U. pertusa and Porphyra haitanensis, and least preferred ones were Sargassum fusiforme and Corallina sessilis. Such an order did not change when one to four relatively preferred seaweeds were removed. The preferred seaweeds were richer in protein and soluble sugar thus higher in energy than the least preferred. In addition, this fish was found to favor filamentous and flat algae rather than calcified ones. Accordingly, the richness of nutrients and morphological characteristics determined the preference of S. canaliculatus for tested macroalgae.

Estructura de la comunidad y distribución vertical de la macrofauna de fondos blandos en isla Gorgona, Pacífico Colombiano

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Bellineth Valencia

2014-02-01

Full Text Available Resumen Se evaluó la variación temporal, espacial y vertical de la estructura comunitaria de la macrofauna de fondos blandos submareales en isla Gorgona, Pacífico colombiano. Las muestras fueron colectadas en marzo y junio de 2011 mediante descorazonadores a 10m de profundidad en cinco puntos alrededor de la isla. Se registraron un total de 73 especies; poliquetos (55% y crustáceos (30% fueron los grupos dominantes en número de individuos. La estructura comunitaria evaluada mediante análisis de clasificación y ordenación, no varió temporalmente, pero si presentó diferencias entre puntos de muestreo, al parecer relacionada con la estructura del sedimento. Las mayores abundancias de la macrofauna se registraron en puntos con dominancia de partículas finas (Farallones, pero en otro punto con sustrato similar (Planchón, la abundancia fue baja, al parecer por la bioperturbación ejercida por el pez Heteroconger sp. La presencia de Heteroconger sp. en el Planchón posiblemente afectó la distribución vertical de la macrofauna, ya que en este último punto la abundancia relativa fue homogénea entre las capas analizadas (1-2-3-4-5-10cm. En los otros cuatro sitios, la abundancia de la macrofauna estuvo limitada principalmente a los primeros dos centímetros del sedimento. En Playa Blanca y Remanso el sustrato fue principalmente gravoso, registrándose en el último punto la menor riqueza, diversidad y abundancia.

Understanding the association of Escherichia coli with diverse macroalgae in the lagoon of Venice.

Science.gov (United States)

Quero, Grazia M; Fasolato, Luca; Vignaroli, Carla; Luna, Gian Marco

2015-06-04

Recent studies provided evidence that the macroalga Cladopohora in lakes hosts associated Escherichia coli, with consequences on the environmental and human health. We expanded these investigations to other macroalgae (Ulva spp., Sargassum muticum and Undaria pinnatifida) widespread in the lagoon of Venice (Italy). Attached E. coli were abundant, accounting up to 3,250 CFU gram(-1) of alga. Macroalgal-associated isolates belonged to all E. coli phylogroups, including pathogenic ones, and to Escherichia cryptic clades. Attached E. coli showed potential to grow even at in situ temperature on macroalgal extracts as only source of carbon and nutrients, and ability to produce biofilm in vitro. The genotypic diversity of the attached isolates was high, with significant differences between algae and the overlying water. Our evidences suggest that attached populations consist of both resident and transient strains, likely resulting from the heterogeneous input of fecal bacteria from the city. We report that cosmopolitan and invasive macroalgae may serve as source of E. coli, including pathogenic genotypes, and that this habitat can potentially support their growth. Considering the global diffusion of the macroalgae here studied, this phenomenon is likely occurring in other coastal cities worldwide and deserves further investigations from either the sanitary and ecological perspectives.

Understanding the association of Escherichia coli with diverse macroalgae in the lagoon of Venice

Science.gov (United States)

Quero, Grazia M.; Fasolato, Luca; Vignaroli, Carla; Luna, Gian Marco

2015-06-01

Recent studies provided evidence that the macroalga Cladopohora in lakes hosts associated Escherichia coli, with consequences on the environmental and human health. We expanded these investigations to other macroalgae (Ulva spp., Sargassum muticum and Undaria pinnatifida) widespread in the lagoon of Venice (Italy). Attached E. coli were abundant, accounting up to 3,250 CFU gram-1 of alga. Macroalgal-associated isolates belonged to all E. coli phylogroups, including pathogenic ones, and to Escherichia cryptic clades. Attached E. coli showed potential to grow even at in situ temperature on macroalgal extracts as only source of carbon and nutrients, and ability to produce biofilm in vitro. The genotypic diversity of the attached isolates was high, with significant differences between algae and the overlying water. Our evidences suggest that attached populations consist of both resident and transient strains, likely resulting from the heterogeneous input of fecal bacteria from the city. We report that cosmopolitan and invasive macroalgae may serve as source of E. coli, including pathogenic genotypes, and that this habitat can potentially support their growth. Considering the global diffusion of the macroalgae here studied, this phenomenon is likely occurring in other coastal cities worldwide and deserves further investigations from either the sanitary and ecological perspectives.

Biofuel potential production from the Orbetello lagoon macroalgae: A comparison with sunflower feedstock

Energy Technology Data Exchange (ETDEWEB)

Bastianoni, Simone; Coppola, Fazio; Tiezzi, Enzo [Department of Chemical and Biosystems Sciences, Siena University, via della Diana, 2A, 53100 Siena (Italy); Colacevich, Andrea; Borghini, Francesca; Focardi, Silvano [Department of Environmental Sciences, Siena University, via Mattioli 4, 53100 Siena (Italy)

2008-07-15

The diversification of different types and sources of biofuels has become an important energy issue in recent times. The aim of this work is to evaluate the use of two kinds of renewable feedstocks in order to produce biodiesel. We have analyzed the potential production of oil from two species of macroalgae considered as waste coming out from a lagoon system involved in eutrophication and from sunflower seeds. We have tested oil extraction yields of both feedstock. Furthermore, a comparison has been carried out based on the emergy approach, in order to evaluate the sustainability and environmental performance of both processes. The results show that, under present conditions, considering oil extraction yields, the production of oil from sunflower seeds is feasible, because of the lower value of transformity of the final product with respect to macroalgae. On the other hand, the results demonstrate that with improvements of oil extraction methodology, macroalgae could be considered a good residual biomass usable for biofuel production. (author)

Deoxy-liquefaction of three different species of macroalgae to high-quality liquid oil.

Science.gov (United States)

Li, Jinhua; Wang, Guoming; Chen, Ming; Li, Jiedong; Yang, Yaoyao; Zhu, Qiuyan; Jiang, Xiaohuan; Wang, Zonghua; Liu, Haichao

2014-10-01

Three species of macroalgae (Ulva lactuca, Laminaria japonica and Gelidium amansii) were converted into liquid oils via deoxy-liquefaction. The elemental analysis, FTIR and GC-MS results showed that the three liquid oils were all mainly composed of aromatics, phenols, alkanes and alkenes, other oxygen-containing compounds, and some nitrogen-containing compounds though there were some differences in terms of their types or contents due to the different constituents in the macroalgae feedstocks. The oxygen content was only 5.15-7.30% and the H/C molar ratio was up to 1.57-1.73. Accordingly, the HHV of the three oils were 42.50, 41.76 and 40.00 MJ/kg, respectively. The results suggested that U. lactuca, L. japonica and G. amansii have potential as biomass feedstock for fuel and chemicals and that deoxy-liquefaction technique may be an effective way to convert macroalgae into high-quality liquid oil. Copyright © 2014 Elsevier Ltd. All rights reserved.

First record of Ostreopsis cfr. ovata on macroalgae in the Northern Adriatic Sea

International Nuclear Information System (INIS)

Monti, Marina; Minocci, Marco; Beran, Alfred; Ivesa, Ljiljana

2007-01-01

Ostreopsis ovata is an epiphytic potentially toxic dinoflagellate. It has a world-wide distribution, normally associated with other epiphytic or benthic dinoflagellates. In tropical seas O. ovata is often associated with the genera Gambierdiscus, Coolia and Prorocentrum, causing cinguatera fish poisoning. Recently, Ostreopsis spp. blooms in the Tyrrhenian and southern Adriatic Sea have been related to human health problems, such as breathing and skin irritation. Here we report the first record of Ostreopsis cfr. ovata in the Northern Adriatic Sea. O. cfr. ovata was isolated from macroalgae in two areas, the Gulf of Trieste (Italy) and close to Rovinj (Croatia). The microalga was identified by scanning electron microscopy and by fluorescence light microscopy. Size range and thecal pore structure were similar to those described for O. cfr. ovata in previous studies. Ostreopsis cfr. ovata was present on all the macroalgae collected, particularly browns and reds. The microalgal association on macroalgae was mostly composed of Ostreopsis sp., Coolia monotis and Coscinodiscus sp

First record of Ostreopsis cfr. ovata on macroalgae in the Northern Adriatic Sea

Energy Technology Data Exchange (ETDEWEB)

Monti, Marina [Department of Biological Oceanography, National Institute of Oceanography and Applied Geophysics, Via Auguste Piccard 54, 34010 Trieste (Italy)]. E-mail: mmonti@inogs.it; Minocci, Marco [Department of Biological Oceanography, National Institute of Oceanography and Applied Geophysics, Via Auguste Piccard 54, 34010 Trieste (Italy); Beran, Alfred [Department of Biological Oceanography, National Institute of Oceanography and Applied Geophysics, Via Auguste Piccard 54, 34010 Trieste (Italy); Ivesa, Ljiljana [Ruder Boskovic Institute, Center for Marine Research, G. Paliaga 5, 52210 Rovinj (Croatia)

2007-05-15

Ostreopsis ovata is an epiphytic potentially toxic dinoflagellate. It has a world-wide distribution, normally associated with other epiphytic or benthic dinoflagellates. In tropical seas O. ovata is often associated with the genera Gambierdiscus, Coolia and Prorocentrum, causing cinguatera fish poisoning. Recently, Ostreopsis spp. blooms in the Tyrrhenian and southern Adriatic Sea have been related to human health problems, such as breathing and skin irritation. Here we report the first record of Ostreopsis cfr. ovata in the Northern Adriatic Sea. O. cfr. ovata was isolated from macroalgae in two areas, the Gulf of Trieste (Italy) and close to Rovinj (Croatia). The microalga was identified by scanning electron microscopy and by fluorescence light microscopy. Size range and thecal pore structure were similar to those described for O. cfr. ovata in previous studies. Ostreopsis cfr. ovata was present on all the macroalgae collected, particularly browns and reds. The microalgal association on macroalgae was mostly composed of Ostreopsis sp., Coolia monotis and Coscinodiscus sp.

Functional trait responses to sediment deposition reduce macrofauna-mediated ecosystem functioning in an estuarine mudflat

Science.gov (United States)

Mestdagh, Sebastiaan; Bagaço, Leila; Braeckman, Ulrike; Ysebaert, Tom; De Smet, Bart; Moens, Tom; Van Colen, Carl

2018-05-01

Human activities, among which dredging and land use change in river basins, are altering estuarine ecosystems. These activities may result in changes in sedimentary processes, affecting biodiversity of sediment macrofauna. As macrofauna controls sediment chemistry and fluxes of energy and matter between water column and sediment, changes in the structure of macrobenthic communities could affect the functioning of an entire ecosystem. We assessed the impact of sediment deposition on intertidal macrobenthic communities and on rates of an important ecosystem function, i.e. sediment community oxygen consumption (SCOC). An experiment was performed with undisturbed sediment samples from the Scheldt river estuary (SW Netherlands). The samples were subjected to four sedimentation regimes: one control and three with a deposited sediment layer of 1, 2 or 5 cm. Oxygen consumption was measured during incubation at ambient temperature. Luminophores applied at the surface, and a seawater-bromide mixture, served as tracers for bioturbation and bio-irrigation, respectively. After incubation, the macrofauna was extracted, identified, and counted and then classified into functional groups based on motility and sediment reworking capacity. Total macrofaunal densities dropped already under the thinnest deposits. The most affected fauna were surficial and low-motility animals, occurring at high densities in the control. Their mortality resulted in a drop in SCOC, which decreased steadily with increasing deposit thickness, while bio-irrigation and bioturbation activity showed increases in the lower sediment deposition regimes but decreases in the more extreme treatments. The initial increased activity likely counteracted the effects of the drop in low-motility, surficial fauna densities, resulting in a steady rather than sudden fall in oxygen consumption. We conclude that the functional identity in terms of motility and sediment reworking can be crucial in our understanding of the

Functional trait responses to sediment deposition reduce macrofauna-mediated ecosystem functioning in an estuarine mudflat

Directory of Open Access Journals (Sweden)

S. Mestdagh

2018-05-01

Full Text Available Human activities, among which dredging and land use change in river basins, are altering estuarine ecosystems. These activities may result in changes in sedimentary processes, affecting biodiversity of sediment macrofauna. As macrofauna controls sediment chemistry and fluxes of energy and matter between water column and sediment, changes in the structure of macrobenthic communities could affect the functioning of an entire ecosystem. We assessed the impact of sediment deposition on intertidal macrobenthic communities and on rates of an important ecosystem function, i.e. sediment community oxygen consumption (SCOC. An experiment was performed with undisturbed sediment samples from the Scheldt river estuary (SW Netherlands. The samples were subjected to four sedimentation regimes: one control and three with a deposited sediment layer of 1, 2 or 5 cm. Oxygen consumption was measured during incubation at ambient temperature. Luminophores applied at the surface, and a seawater–bromide mixture, served as tracers for bioturbation and bio-irrigation, respectively. After incubation, the macrofauna was extracted, identified, and counted and then classified into functional groups based on motility and sediment reworking capacity. Total macrofaunal densities dropped already under the thinnest deposits. The most affected fauna were surficial and low-motility animals, occurring at high densities in the control. Their mortality resulted in a drop in SCOC, which decreased steadily with increasing deposit thickness, while bio-irrigation and bioturbation activity showed increases in the lower sediment deposition regimes but decreases in the more extreme treatments. The initial increased activity likely counteracted the effects of the drop in low-motility, surficial fauna densities, resulting in a steady rather than sudden fall in oxygen consumption. We conclude that the functional identity in terms of motility and sediment reworking can be crucial in our

Analysis of Environmental Physical-Chemical Factors and Macroalga Species In The Coastal Water of Nusalaut, Central Maluku - Indonesia

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Karel Melsasail

2018-03-01

Full Text Available The physical-chemical factors of environment are very influential on the presence and the growth of macrolaga in waters. Well-maintained water habitat is a good environment for the growth of macroalgae. A research has been conducted on the physicochemical environmental factors and the macroalgae species in the coastal waters of Nusalaut Island using transect method, and it was a survey research on four different observation stations. The results of the research showed that station I (Amet Village has the best physicochemical factors for the presence and the growth of macroalgae, compared to station II (Nalahia Village, station III (Sila Village and station IV (Leinitu Village. The most widely found macro algae are from the Rhodophyta class, with a total of 17 species of macroalgae, of which 15 species are found in station I.

An economic model for offshore cultivation of macroalgae

NARCIS (Netherlands)

Dijk, van Wim; Schoot, van der Jan Rinze; Edwards, Maeve; Queguineur, Benoit; Champenois, Jennifer; Mooney, Karen; Barrento, Sara

2015-01-01

Algae biomass is considered as a potential non-fossil source of raw materials to produce fuel, feed, chemicals and materials. For this purpose microalgae as well as macroalgae can be used, and in this report we focus on the latter. More than 99% of the world production of aquatic plants is produced

Spatio-temporal distribution patterns of the invasive macroalga Sargassum muticum within a Danish Sargassum-bed

DEFF Research Database (Denmark)

Thomsen, M. S.; Wernberg, T.; Stæhr, P. A.

2006-01-01

Sargassum muticum was first observed in Scandinavia in Limfjorden (Denmark) in 1984, where it is now the most abundant and conspicuous macroalga. Despite the ecological importance of Sargassum, few studies have described seasonal patterns within Scandinavian Sargassum beds. We quantified the dyna...... and sediment stress limits Sargasum in shallow waters, and the presence of stable boulder substratum facilitate Sargassum. Competition for space from other macroalgae and herbivory are probably of minor importance.......Sargassum muticum was first observed in Scandinavia in Limfjorden (Denmark) in 1984, where it is now the most abundant and conspicuous macroalga. Despite the ecological importance of Sargassum, few studies have described seasonal patterns within Scandinavian Sargassum beds. We quantified...... the dynamics of macroalgae among years and seasons along a depth transect through a typical Sargassum bed in Limfjorden. The annual investigations (summer transects 1989-1999) showed a gradual increase in the dominance of Sargassum, especially at the 2-4-m depth interval. Significant seasonal dynamics...

In situ monitoring of molecular changes during cell differentiation processes in marine macroalgae through mass spectrometric imaging.

Science.gov (United States)

Kessler, Ralf W; Crecelius, Anna C; Schubert, Ulrich S; Wichard, Thomas

2017-08-01

Matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI-MSI) was employed to discriminate between cell differentiation processes in macroalgae. One of the key developmental processes in the algal life cycle is the production of germ cells (gametes and zoids). The gametogenesis of the marine green macroalga Ulva mutabilis (Chlorophyta) was monitored by metabolomic snapshots of the surface, when blade cells differentiate synchronously into gametangia and giving rise to gametes. To establish MSI for macroalgae, dimethylsulfoniopropionate (DMSP), a known algal osmolyte, was determined. MSI of the surface of U. mutabilis followed by chemometric data analysis revealed dynamic metabolomic changes during cell differentiation. DMSP and a total of 55 specific molecular biomarkers, which could be assigned to important stages of the gametogenesis, were detected. Our research contributes to the understanding of molecular mechanisms underlying macroalgal cell differentiation. Graphical abstract Molecular changes during cell differentiation of the marine macroalga Ulva were visualized by matrix assisted laser desorption/ionization mass spectrometric imaging (MALDI-MSI).

Stable nitrogen isotopes in coastal macroalgae: Geographic and anthropogenic variability

Energy Technology Data Exchange (ETDEWEB)

Viana, Inés G., E-mail: ines.gonzalez@co.ieo.es; Bode, Antonio

2013-01-15

Growing human population adds to the natural nitrogen loads to coastal waters. Both anthropogenic and natural nitrogen is readily incorporated in new biomass, and these different nitrogen sources may be traced by the measurement of the ratio of stable nitrogen isotopes (δ{sup 15}N). In this study δ{sup 15}N was determined in two species of macroalgae (Ascophyllum nodosum and Fucus vesiculosus), and in nitrate and ammonium to determine the relative importance of anthropogenic versus natural sources of nitrogen along the coast of NW Spain. Both algal species and nitrogen sources showed similar isotopic enrichment for a given site, but algal δ{sup 15}N was not related to either inorganic nitrogen concentrations or δ{sup 15}N in the water samples. The latter suggests that inorganic nitrogen inputs are variable and do not always leave an isotopic trace in macroalgae. However, a significant linear decrease in macroalgal δ{sup 15}N along the coast is consistent with the differential effect of upwelling. Besides this geographic variability, the influence of anthropogenic nitrogen sources is evidenced by higher δ{sup 15}N in macroalgae from rias and estuaries compared to those from open coastal areas and in areas with more than 15 × 10{sup 3} inhabitants in the watershed. These results indicate that, in contrast with other studies, macroalgal δ{sup 15}N is not simply related to either inorganic nitrogen concentrations or human population size but depends on other factors as the upwelling or the efficiency of local waste treatment systems. - Highlights: ► Anthropogenic versus upwelling nitrogen effect on macroalgal δ{sup 15}N was studied. ► The influence of populations and upwelling has not been made before on macroalgal δ{sup 15}N. ► Natural variability has not been taken into account in most biomonitoring studies. ► Upwelling explains most of the variability in δ{sup 15}N in macroalgae.

Variation in soil macro-fauna diversity in seven humus orders of a Parrotio-Carpinetum forest association on Chromic Cambisols of Shast-klateh area in Iran

Science.gov (United States)

Izadi, M.; Habashi, H.; Waez-Mousavi, S. M.

2017-03-01

Soil biodiversity includes organisms which spend a part or all of their life cycle on or in the soil. Among soil-dwelling animals, macro-fauna as an important group of animals have important effects on the dynamics of soil organic matter and litter decomposition process. The humus forms interact with the climatic conditions, flora, as well as soil fauna, and microbial activity. In new humus form classifications, soil organisms play an important role in separation of humus horizons from one another. The subject of this study was to determine the diversity of macro fauna for different humus forms. We determined humus forms using morphological classification, and then 69 random samples were taken from plots of 100 cm2 in area, and soil macro-fauna species were collected by hand sorting method. Two classes of humus forms, including Mull (with three humus orders, namely Dysmull, Oligomull, and Mesomull,) and Amphi (with four humus orders, namely Leptoamphi, Eumacroamphi, Eumesoamphi, and Pachyamphi) were identified. A number of 13 macro-fauna orders were identified using identification key. Among the humus orders, Shannon diversity, Simpson evenness and Margalef richness indices were the highest in Pachyamphi order. Arthropod diversity in Pachyamphi humus order was higher than those of Mull. These results showed that diversity of soil macrofauna increase by increasing the thickness of the organic horizons (OL, OF, OH), especially OH horizon.

The Effect of CO2 Injection on Macroalgae Gelidium latifolium Biomass Growth Rate and Carbohydrate Content

Directory of Open Access Journals (Sweden)

Mujizat Kawaroe

2016-06-01

Full Text Available There are many species of macroalga grow in marine ecosystem and potentially as raw material for bioethanol resource. Bioethanol is a conversion result of carbohydrate, one of macroalgae biomass content. The exploration of macroalgae require information about  growth rate ability to determine availability in the nature. This research analyze growth rate and carbohydrate content of marine macroalga Gelidium latifolium on cultivation using varied injection of carbon dioxide and aeration. The treatments were control (K, 2000 cc CO2 injection and aeration (P1, 3000 cc CO2 injection and aeration (P2, 2000 cc CO2 injection without aeration (P3, and 3000 cc CO2 injection without aeration (P4. Samples weight were 3 gram in early cultivation on laboratorium scale for 42 days observation. The results showed that the daily growth rate Gelidium latifolium during the study ranged from 0.02-1.06%. The highest daily growth rate was 1.06±0.14% (P2. Carbohydrate yield was 18.23% in early cultivation then 19.40% (K and P2, 20.40% (P1, 16.87% (K3, and 16.40% (P4 after cultivation. The high of carbohydrates value may not guarantee the sustainable Gelidium latifolium biomass utilization as raw material for bioethanol production because of the low growth rate, thus it is necessary to modified and encourage cultivation method effectively. Keywords: CO2 injection, growth rate, carbohydrate, macroalgae, Gelidium latifolium

The Effect of Various Species of Macroalgae on the Growth, Survival, and Toxicity of Karenia brevis

Science.gov (United States)

Gardner, K. G.; Lovko, V. J.; Henry, M. S.

2016-02-01

Harmful algal blooms (HABs) caused by the dinoflagellate Karenia brevis produce toxins that result in negative impacts to both humans and the environment. Little is known about the termination stages of these blooms, and few viable control mechanisms have been suggested. Natural, algae derived compounds have been proposed as a way to limit bloom growth and reduce brevetoxins in the water column. The work presented here examines the ability of macroalgae to inhibit the growth or survival of K. brevis, similar to what has been demonstrated with other red tide species. Additionally, we attempted to determine if macroalgae decreases water column brevetoxins which, to our knowledge, has not been tested with macroalgae but has been demonstrated in other studies with microalgal species. The macroalgae species Dictyota sp. and Gracilaria sp. caused 100% mortality of K. brevis in under 24 hours. Compared to the control, 7 other species significantly decreased the growth rate of K. brevis. The Dictyota treatments showed significant toxin reduction and increase of the antitoxin brevanol. These results indicate that some combination of compounds produced by macroalgae inhibit growth and survival of K. brevis and possibly limit their toxin production. Future studies will attempt to isolate and identify these compounds and test their effects on other marine organisms such as diatoms. Determining the interactions between HAB species K. brevis and macroalgal species will provide insights on the mechanism of bloom termination and a potential control method.

Macroalgae blooms and δ15N in subtropical coastal lagoons from the Southeastern Gulf of California: Discrimination among agricultural, shrimp farm and sewage effluents

International Nuclear Information System (INIS)

Pinon-Gimate, Alejandra; Soto-Jimenez, Martin F.; Ochoa-Izaguirre, Maria Julia; Garcia-Pages, Eynar; Paez-Osuna, Federico

2009-01-01

Macroalgae blooms of Gracilaria vermiculophylla, Hypnea spinella and Spyridia filamentosa have been found in coastal lagoons in the SE Gulf of California. Agriculture, livestock, shrimp and poultry farms and sewage contribute anthropogenic nitrogen to the systems. The δ 15 N of these sources, water column and macroalgae were studied in order to identify the N supply for macroalgae blooms. δ 15 N of three species of macroalgae (4.3-13.6 per mille ) were enriched compared to the water column (δ 15 N-NO 3 - 3.7-6.8 per mille ), probably because of fractioning from the macroalgae. δ 15 N of POM (1.4-10.3 per mille ) was similar to the water column but the relationship was unclear. Depending on the site, macroalgae showed different δ 15 N values since some sites receive more or less influence from one given source of the associated watershed, which is reflected in the different δ 15 N values of the macroalgae of the same system and in the relative contributions of the sources.

Macroalgas de riachos da Floresta Nacional de Irati, região centro-sul do Estado do Paraná, Sul do Brasil Stream macroalgae of Irati National Forest, mid-southern Paraná State, Southern Brazil

Directory of Open Access Journals (Sweden)

Ciro Cesar Zanini Branco

2008-06-01

Full Text Available Estudos florísticos das comunidades de macroalgas lóticas no Brasil são quase que exclusivamente baseadas em material do Estado de São Paulo. Informações sobre macroalgas de riachos são virtualmente ausentes no Estado do Paraná. Considerando a carência de trabalhos sobre estes importantes produtores primários de ambientes lóticos, foi realizado um estudo mais amplo, a fim de conhecer melhor a biodiversidade das comunidades de macroalgas no Paraná. Neste contexto, o presente trabalho teve como objetivo realizar o levantamento florístico das comunidades de macroalgas da Floresta Nacional de Irati (Flona de Irati, uma unidade de conservação que protege uma área de Floresta Ombrófila Mista (Mata de Araucária. Os estudos foram desenvolvidos em 11 riachos, através de duas coletas realizadas durante os períodos de 19-21 de julho/2005 e 2-4 de fevereiro/2006. Em cada riacho foi estabelecido um segmento de 10 metros de extensão, no qual foi realizado o exame visual detalhado do substrato a fim de determinar a presença de macroalgas. Além da presença das macroalgas, as seguintes variáveis ambientais foram medidas em cada data de amostragem: temperatura, turbidez, condutividade específica, pH, oxigênio dissolvido, profundidade, nutrientes, cor da água e demanda química de oxigênio (DQO. O levantamento taxonômico resultou na identificação de 23 táxons e mostrou a dominância, em termos de número de táxons, de Chlorophyta sobre as demais divisões. O gênero Phormidium Kützing ex Gomont foi o único representado por mais de uma espécie. De modo geral, a maioria das espécies encontradas na Flona de Irati tem sido reportada em estudos prévios, entretanto, uma parte significativa das macroalgas inventariadas foi formada por táxons de ocorrência rara em riachos brasileiros ou, até mesmo, prováveis novidades para a ciência.Surveys of stream macroalgal communities in Brazil are almost exclusively based on data from S�

Demineralization of Sargassum spp. Macroalgae Biomass: Selective Hydrothermal Liquefaction Process for Bio-Oil Production

OpenAIRE

Díaz-Vázquez, Liz M.; Rojas-Pérez, Arnulfo; Fuentes-Caraballo, Mariela; Robles, Isis V.; Jena, Umakanta; Das, K. C.

2015-01-01

Algae biomasses are considered a viable option for the production of biofuel because of their high yields of oil produced per dry weight. Brown macroalgae Sargassum spp. are one of the most abundant species of algae in the shores of Puerto Rico. Its availability in large quantity presents a great opportunity for use as a source of renewable energy. However, high ash content of macroalgae affects the conversion processes and the quality of resulting fuel products. This research studied the eff...

Methane production from marine macroalgae. A literature study with comments

Energy Technology Data Exchange (ETDEWEB)

Josefsen, K.; Aasen, I.M.

1995-06-16

This report is a survey of the published literature on fermentation of marine macroalgae to produce methane. The emphasis is placed on modern fermentation process development, including both bio-technological and economic parameters. Marine macroalgae are mostly good feedstock for methane fermentation. The main carbohydrates in seaweeds are alginate, laminaria and mannitol. Both the N and P content of kelp are usually high enough to avoid nutrient limitation. The biogass produced from marine macroalgae usually contains 50 - 65% methane. Experimentally methane yields in the order of 0.35 - 0.43 m{sup 3}/kg volatile solids (VS) have been obtained from Macrocystis pyrifera and 0.20 - 0.30 m{sup 3}/kg VS for Laminaria sp. at long retention times (50-60 days) in completely mixed reactors. The maximum reported production rate in a completely mixed reactor is 2.7 vol CH{sub 4}/reactor volume x day for M. pyrifera. In reactor configurations giving longer solids retention times (SRT) than liquid retention times (LRT), the highest reported productivity was 3.3 vol/vol x day, with loading rate 9.6 kg VS/m{sup 3} x day, HRT 10 days and SRT 23 days. There are discussions of special problems related to fermentation of marine algae, in particular the sulphur content, the toxicity of H{sub 2}S and the precipitation of heavy metals as sulphides. 72 refs., 5 figs., 13 tabs.

Utilização de ostra e macroalga como biofiltro para efluentes de cultivo de camarão marinho

OpenAIRE

Iru Menezes Guimarães

2008-01-01

A eficiência de um sistema de tratamento integrado para melhorar a qualidade da água de viveiros de camarão foi avaliada utilizando-se processos sedimentação, filtração por ostras e absorção por macroalgas, assim como também foram avaliadas diferentes densidades de ostra e macroalga no tratamento de efluentes de sistemas autotrófico e heterotrófico de cultivo de camarão. Espécie nativa de ostra (Crassostrea rhizophorae) e macroalga (Gracilaria sp.) foram selecionadas devido a disponibil...

Anti-Phytopathogenic Activities of Macro-Algae Extracts

Directory of Open Access Journals (Sweden)

Ingrid Ramírez

2011-05-01

Full Text Available Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.

Natural diet of three species of shrimp in a tropical coastal lagoon

Directory of Open Access Journals (Sweden)

Albertoni Edélti Faria

2003-01-01

Full Text Available The gut content of 495 specimens of Farfantepenaeus brasiliensis, 131 of F. paulensis (Penaeidae and 102 of Macrobrachium acanthurus (Palaemonidae were analyzed to establish the composition of their diets F. brasiliensis had as the most important feeding items in its diet larvae of Chironomidae, Polychaeta and Heleobia australis (Mollusca. For F. paulensis, the most important items were the same as for F. brasiliensis, but the order of importance of H. australis and Polychaeta was inverted. M. acanthurus had detritus as the most important item, followed by Chironomidae larvae, Odonata nymphs, and fragments of the macroalgae Chara. The results showed that the three species were omnivorous, with a varied diet including both components of macrofauna of benthos and associated to the macroalgae Chara and plant fragments and detritus.

Macroalgae-Derived Biofuel: A Review of Methods of Energy Extraction from Seaweed Biomass

Directory of Open Access Journals (Sweden)

John J. Milledge

2014-11-01

Full Text Available The potential of algal biomass as a source of liquid and gaseous biofuels is a highly topical theme, but as yet there is no successful economically viable commercial system producing biofuel. However, the majority of the research has focused on producing fuels from microalgae rather than from macroalgae. This article briefly reviews the methods by which useful energy may be extracted from macroalgae biomass including: direct combustion, pyrolysis, gasification, trans-esterification to biodiesel, hydrothermal liquefaction, fermentation to bioethanol, fermentation to biobutanol and anaerobic digestion, and explores technical and engineering difficulties that remain to be resolved.

Benthic macrofauna variations and community structure in Cenomanian cyclic chalk-marl from Southerham Grey Pit, SE England

DEFF Research Database (Denmark)

Lauridsen, Bodil Wesenberg; Gale, A. S.; Surlyk, Finn

2009-01-01

Cenomanian chalk-marl couplets from England represent the 20 ka Milankovitch precession cycle. Fossil communities from both chalk and marl are identified to test if the orbital fluctuations and the associated changes in substrate lithology and climate exerted any control on the benthic macrofauna...

Effects of Ocean Acidification and Temperature Increases on the Photosynthesis of Tropical Reef Calcified Macroalgae.

Science.gov (United States)

Scherner, Fernando; Pereira, Cristiano Macedo; Duarte, Gustavo; Horta, Paulo Antunes; E Castro, Clovis Barreira; Barufi, José Bonomi; Pereira, Sonia Maria Barreto

2016-01-01

Climate change is a global phenomenon that is considered an important threat to marine ecosystems. Ocean acidification and increased seawater temperatures are among the consequences of this phenomenon. The comprehension of the effects of these alterations on marine organisms, in particular on calcified macroalgae, is still modest despite its great importance. There are evidences that macroalgae inhabiting highly variable environments are relatively resilient to such changes. Thus, the aim of this study was to evaluate experimentally the effects of CO2-driven ocean acidification and temperature rises on the photosynthesis of calcified macroalgae inhabiting the intertidal region, a highly variable environment. The experiments were performed in a reef mesocosm in a tropical region on the Brazilian coast, using three species of frondose calcifying macroalgae (Halimeda cuneata, Padina gymnospora, and Tricleocarpa cylindrica) and crustose coralline algae. The acidification experiment consisted of three treatments with pH levels below those occurring in the region (-0.3, -0.6, -0.9). For the temperature experiment, three temperature levels above those occurring naturally in the region (+1, +2, +4°C) were determined. The results of the acidification experiment indicate an increase on the optimum quantum yield by T. cylindrica and a decline of this parameter by coralline algae, although both only occurred at the extreme acidification treatment (-0.9). The energy dissipation mechanisms of these algae were also altered at this extreme condition. Significant effects of the temperature experiment were limited to an enhancement of the photosynthetic performance by H. cuneata although only at a modest temperature increase (+1°C). In general, the results indicate a possible photosynthetic adaptation and/or acclimation of the studied macroalgae to the expected future ocean acidification and temperature rises, as separate factors. Such relative resilience may be a result of the

Investigation of mangrove macroalgae as biomonitors of estuarine metal contamination

Energy Technology Data Exchange (ETDEWEB)

Melville, Felicity [Department of Environmental Sciences/Institute of Water and Environmental Resource Management, University of Technology, Sydney, PO Box 123, Broadway NSW 2007 (Australia)], E-mail: f.melville@cqu.edu.au; Pulkownik, Alex [Department of Environmental Sciences/Institute of Water and Environmental Resource Management, University of Technology, Sydney, PO Box 123, Broadway NSW 2007 (Australia)

2007-11-15

This study examined the potential use of macroalgae epiphytic on mangrove aerial roots as biomonitors of estuarine contamination. The metal concentrations of macroalgae were investigated in four estuaries in the vicinity of Sydney, Australia, and compared to water and sediment metal concentrations over three seasonal surveys. Macroalgal metal concentrations (copper, zinc, cadmium, chromium, lead, nickel, manganese and iron) appeared to be more associated with sediment metal concentrations than water concentrations, suggesting they may be useful biomonitors of estuarine sediment contamination. Algae in the more contaminated estuaries generally contained higher metal concentrations. However, concentrations of iron, nickel and manganese appeared to be similar in the algae despite the varying sediment concentrations, while accumulation of copper, zinc, lead and chromium appeared to be associated with ambient environmental concentrations. The uptake of metals also varied among the different species, suggesting that algal parameters, such as morphology, may also influence metal uptake and accumulation.

Efficient ethanol production from brown macroalgae sugars by a synthetic yeast platform.

Science.gov (United States)

Enquist-Newman, Maria; Faust, Ann Marie E; Bravo, Daniel D; Santos, Christine Nicole S; Raisner, Ryan M; Hanel, Arthur; Sarvabhowman, Preethi; Le, Chi; Regitsky, Drew D; Cooper, Susan R; Peereboom, Lars; Clark, Alana; Martinez, Yessica; Goldsmith, Joshua; Cho, Min Y; Donohoue, Paul D; Luo, Lily; Lamberson, Brigit; Tamrakar, Pramila; Kim, Edward J; Villari, Jeffrey L; Gill, Avinash; Tripathi, Shital A; Karamchedu, Padma; Paredes, Carlos J; Rajgarhia, Vineet; Kotlar, Hans Kristian; Bailey, Richard B; Miller, Dennis J; Ohler, Nicholas L; Swimmer, Candace; Yoshikuni, Yasuo

2014-01-09

The increasing demands placed on natural resources for fuel and food production require that we explore the use of efficient, sustainable feedstocks such as brown macroalgae. The full potential of brown macroalgae as feedstocks for commercial-scale fuel ethanol production, however, requires extensive re-engineering of the alginate and mannitol catabolic pathways in the standard industrial microbe Saccharomyces cerevisiae. Here we present the discovery of an alginate monomer (4-deoxy-L-erythro-5-hexoseulose uronate, or DEHU) transporter from the alginolytic eukaryote Asteromyces cruciatus. The genomic integration and overexpression of the gene encoding this transporter, together with the necessary bacterial alginate and deregulated native mannitol catabolism genes, conferred the ability of an S. cerevisiae strain to efficiently metabolize DEHU and mannitol. When this platform was further adapted to grow on mannitol and DEHU under anaerobic conditions, it was capable of ethanol fermentation from mannitol and DEHU, achieving titres of 4.6% (v/v) (36.2 g l(-1)) and yields up to 83% of the maximum theoretical yield from consumed sugars. These results show that all major sugars in brown macroalgae can be used as feedstocks for biofuels and value-added renewable chemicals in a manner that is comparable to traditional arable-land-based feedstocks.

Design and economic analysis of a macroalgae-to-butanol process via a thermochemical route

International Nuclear Information System (INIS)

Okoli, Chinedu O.; Adams, Thomas A.; Brigljević, Boris; Liu, Jay J.

2016-01-01

Highlights: • Novel macroalgae-to-butanol plants are designed and assessed for U.S. and S. Korea. • The lowest MBSP of 1.97 $/L was obtained for the S. Korean natural gas import plant. • S. Korean plant with no fossil utilities had lowest CO_2 avoided cost of 620 $/tCO_2e. • Macroalgae-to-butanol plants CO_2 avoided costs are competitive with other biofuels. • CO_2 avoided costs of assessed plants are most sensitive to changes in gasoline price. - Abstract: In this work, a first of its kind assessment of butanol production from macroalgae through a thermochemical route is carried out. Different process configurations were designed and simulated in Aspen Plus to quantify their mass and energy balances. Furthermore, economic and environmental metrics such as the minimum butanol selling price (MBSP), and cost of CO_2 equivalent emissions (CO_2e) avoided were used to assess the potential of the different configurations under different market scenarios, with comparisons carried out amongst the configurations as well as against standard literature references of similar processes. Finally, a sensitivity analysis was used to assess the impact that changes in key parameters have on the considered metrics. The results show that configurations which import natural gas and electricity as utility sources alongside the macroalgae feedstock offer the lowest MBSP, however they do poorly when cost of CO_2e avoided is considered. On the other hand, the configurations which utilize only macroalgae offer the best potential for cost of CO_2e avoided but have the poorest values for MBSP. In addition, the cost of CO_2e avoided obtained for the best configurations are in line with literature references. However, the MBSP values are higher than literature references for butanol derived from cellulosic feedstock primarily due to the high ash content in seaweed. The sensitivity analyses results show that changes in gasoline prices have a very significant effect on the plant

Proximate - Production of Macroalgae for Human Consumption in the Pacific Northwest

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This proposal will focus on the production of fresh macroalgae in a land-based system. This type of production system avoids the regulatory and permitting issues...

Growth - Production of Macroalgae for Human Consumption in the Pacific Northwest

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This proposal will focus on the production of fresh macroalgae in a land-based system. This type of production system avoids the regulatory and permitting issues...

Stable nitrogen isotopes in coastal macroalgae: geographic and anthropogenic variability.

Science.gov (United States)

Viana, Inés G; Bode, Antonio

2013-01-15

Growing human population adds to the natural nitrogen loads to coastal waters. Both anthropogenic and natural nitrogen is readily incorporated in new biomass, and these different nitrogen sources may be traced by the measurement of the ratio of stable nitrogen isotopes (δ(15)N). In this study δ(15)N was determined in two species of macroalgae (Ascophyllum nodosum and Fucus vesiculosus), and in nitrate and ammonium to determine the relative importance of anthropogenic versus natural sources of nitrogen along the coast of NW Spain. Both algal species and nitrogen sources showed similar isotopic enrichment for a given site, but algal δ(15)N was not related to either inorganic nitrogen concentrations or δ(15)N in the water samples. The latter suggests that inorganic nitrogen inputs are variable and do not always leave an isotopic trace in macroalgae. However, a significant linear decrease in macroalgal δ(15)N along the coast is consistent with the differential effect of upwelling. Besides this geographic variability, the influence of anthropogenic nitrogen sources is evidenced by higher δ(15)N in macroalgae from rias and estuaries compared to those from open coastal areas and in areas with more than 15×10(3) inhabitants in the watershed. These results indicate that, in contrast with other studies, macroalgal δ(15)N is not simply related to either inorganic nitrogen concentrations or human population size but depends on other factors as the upwelling or the efficiency of local waste treatment systems. Copyright © 2012 Elsevier B.V. All rights reserved.

The distribution of macrofauna on the inner continental shelf of southeastern Brazil: The major influence of an estuarine system

Science.gov (United States)

Zalmon, I. R.; Macedo, I. M.; Rezende, C. E.; Falcão, A. P. C.; Almeida, T. C.

2013-09-01

The environmental heterogeneity of the Campos Basin on the northern coast of Rio de Janeiro State was assessed by the benthic macrofauna on the platform adjacent to the Paraíba do Sul River (PSR) on the dry and rainy seasons. The samples were collected in triplicate from 33 sites using a van Veen grab during March 2009 - a period of higher precipitation and flow rate - and July 2009 - a period of lower precipitation and flow rate. The grab depths ranged from 12 to 97 m and were grouped into three strata: 1: 50 m. The particle size, total carbonate and total organic carbon in each sample were analyzed. Subsamples for the macrofauna analysis were washed, sieved with a 500 μm mesh and identified. The sediment was predominantly composed of sand, with mud pockets near the mouth of the river. The macrofauna included annelids, crustaceans, mollusks, echinoderms, cnidarians, nemerteans, cephalochordates, sipunculids and bryozoans. The density and richness were directly related to the depth, with both descriptors being higher during the rainy season and at depths greater than 50 m. This result is probably due to the higher availability of food in the river during this period and is corroborated by the predominance of deposit feeders in the deepest stratum. The number of individuals of each species was higher in the shallowest stratum, probably due to the higher productivity of this stratum. The rate of organic particulate matter flow from the coastal regions to the deeper regions can also be influenced by the material export dynamics of the river, which are more intense during the rainy season. These dynamics explain why a significantly higher number of individuals were observed in the rainy period in comparison to the dry one. Multivariate analyses identified differences between the sampling sites in the deepest stratum during both periods and revealed a stronger similarity between the shallow and intermediate strata, especially during the rainy season, which has a

An evaluation of the toxicity and bioaccumulation of bismuth in the coastal environment using three species of macroalga

International Nuclear Information System (INIS)

Kearns, James; Turner, Andrew

2016-01-01

Bismuth is a heavy metal whose biogeochemical behaviour in the marine environment is poorly defined. In this study, we exposed three different species of macroalga (the chlorophyte, Ulva lactuca, the phaeophyte, Fucus vesiculosus, and the rhodophyte, Chondrus crispus) to different concentrations of Bi (up to 50 μg L −1 ) under controlled, laboratory conditions. After a period of 48-h, the phytotoxicity of Bi was measured in terms of chlorophyll fluorescence quenching, and adsorption and internalisation of Bi determined by ICP after EDTA extraction and acid digestion, respectively. For all algae, both the internalisation and total accumulation of Bi were proportional to the concentration of aqueous metal. Total accumulation followed the order: F. vesiculosus > C. crispus > U. lactuca; with respective accumulation factors of about 4200, 1700 and 600 L kg −1 . Greatest internalisation (about 33% of total accumulated Bi) was exhibited by C. crispus, the only macroalga to display a phytotoxic response in the exposures. A comparison of the present results with those reported in the literature suggests that Bi accumulation by macroalgae is significantly lower than its accumulation by marine plankton (volume concentration factors of 10 5 to 10 7 ), and that the phytotoxicity of Bi is low relative to other heavy metals like Ag and Tl. - Highlights: • Very little is understood about the biogeochemistry of bismuth. • We exposed three species of coastal macroalga to variable concentrations of Bi. • Greatest accumulation was exhibited by Fucus vesiculosus. • Greatest internalisation was exhibited by Chondus crispus. • C. crispus was the only macroalga to display a toxic response. - Bismuth is accumulated by three species of marine macroalga but exhibits only moderate toxicity to the rhodophyte, Chondrus crispus.

The macrofauna of the soil in systems of agricultural production: Answers to the perturbations and handling perspectives. A case of study in the Oriental Plains of Colombia

International Nuclear Information System (INIS)

Decaens, T; Jimenez, J J; Schneidmadl, J; Lavelle, P

1998-01-01

During the last 20 years, numerous investigations were dedicated to the understanding of the relationships between soil macro-invertebrates and the abiotic factors that determine soil function. Important effects of macro-fauna activities were observed in soil organic matter dynamics, cycles of assimilable nutrients, soil structure and plant growth. Actual investigation in the Eastern Plains of Colombia (Investigation Centre of Carimagua and Matazul Farm) aims to identify sustainable and macrofauna-protecting systems of production; managing savanna results in important changes in soil faunal communities. Sowing improved pastures increases the activity of local macro-invertebrates populations (especially earthworms) and conserves the initial biodiversity of the savanna. On the other hand, monocrops have a dramatic effect on the whole soil macrofauna. An appropriate management of soil tillage and plant residues may minimize the negative effects of such monocrops. Other alternative is the use of rotations and/or juxtapositions of suitable and unfavorable situations, which may facilitates macrofaunal migrations from one system to another

Allelopathic interactions between the opportunistic species Ulva prolifera and the native macroalga Gracilaria lichvoides.

Directory of Open Access Journals (Sweden)

Dong Xu

Full Text Available Allelopathy, one type of direct plant competition, can be a potent mechanism through which plant communities are structured. The aim of this study was to determine whether allelopathic interactions occur between the opportunistic green tide-forming species Ulva prolifera and the native macroalga Gracilaria lichvoides, both of which were collected from the coastline of East China sea. In laboratory experiments, the presence of G. lichvoides at 1.25 g wet weight L(-1 significantly inhibited growth and photosynthesis of U. prolifera at concentrations of 1.25, 2.50, and 3.75 g wet weight L(-1 (p0.05. Culture medium experiments further confirmed that some allelochemicals may be released by both of the tested macroalgae, and these could account for the observed physiological inhibition of growth and photosynthesis. Moreover, the native macroalgae G. lichvoides was a stronger competitor than the opportunistic species U. prolifera. Collectively, the results of the present study represent a significant advance in exploring ecological questions about the effects of green tide blooms on the macroalgal community.

Mollusc diversity associated with the non-indigenous macroalga Asparagopsis armata Harvey, 1855 along the Atlantic coast of the Iberian Peninsula.

Science.gov (United States)

Rubal, Marcos; Costa-Garcia, Ricardo; Besteiro, Celia; Sousa-Pinto, Isabel; Veiga, Puri

2018-05-01

The aims of this study were to explore mollusc assemblages associated with the non-indigenous macroalga Asparagopsis armata, to compare them with those on other macroalgae at the study region and to explore potential differences on mollusc assemblages between two regions in the Atlantic coast of the Iberian Peninsula, where A. armata is present. To achieve this, at each region, four intertidal shores were sampled. Twenty-nine mollusc species were reported and thus, A. armata harboured similar or higher diversity than other annual macroalgae in this area. When compared with perennial macroalgae, results depend on the species and studied area. Moreover, significant differences in structure of mollusc assemblages between the two studied regions were found. However, these were due to differences in the relative abundance of species rather than the presence of exclusive species at each region. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effects of s-triazines on selected marine macroalgae

International Nuclear Information System (INIS)

Lewey, S.A.; Nummela, E.C.

1999-01-01

Although s-triazines have been used as herbicides for many years, their use and that of other herbicides and fungicides, in antifouling compounds is only fairly recent. The Hamble estuary, Hampshire UK has been identified as one such site. Investigations were conducted into the effects of s-triazines on selected marine macroalgae, local to that area

Macroalgae for CO₂ Capture and Renewable Energy - A Pilot Project

Energy Technology Data Exchange (ETDEWEB)

Wiley, Kristine [Gas Technology Inst., Des Plaines, IL (United States)

2011-01-31

The objective of this project was to demonstrate, at a pilot scale, the beneficial use of carbon dioxide (CO₂) through a technology designed to capture CO₂ from fossil-fuel fired power plant stack gas, generating macroalgae and converting the macroalgae at high efficiency to renewable methane that can be utilized in the power plant or introduced into a natural gas pipeline. The proposed pilot plant would demonstrate the cost-effectiveness and CO₂/ NO_x flue-gas removal efficiency of an innovative algal scrubber technology where seaweeds are grown out of water on specially-designed supporting structures contained within greenhouses where the plants are constantly bathed by recycled nutrient sprays enriched by flue gas constituents. The work described in this document addresses Phase 1 of the project only. The scope of work for Phase 1 includes the completion of a preliminary design package; the collection of additional experimental data to support the preliminary and detailed design for a pilot scale utilization of CO₂ to cultivate macroalage and to process that algae to produce methane; and a technological and economic analysis to evaluate the potential of the system. Selection criteria for macroalgae that could survive the elevated temperatures and potential periodic desiccation of near desert project sites were identified. Samples of the selected macroalgae species were obtained and then subjected to anaerobic digestion to determine conversions and potential methane yields. A Process Design Package (PDP) was assembled that included process design, process flow diagram, material balance, instrumentation, and equipment list, sizes, and cost for the Phase 2 pilot plant. Preliminary economic assessments were performed under the various assumptions made, which are purposely conservative. Based on the results, additional development work should be conducted to delineate the areas for improving efficiency, reducing

Allelochemicals Produced by Brown Macroalgae of the Lobophora Genus Are Active against Coral Larvae and Associated Bacteria, Supporting Pathogenic Shifts to Vibrio Dominance.

Science.gov (United States)

Morrow, Kathleen M; Bromhall, Katrina; Motti, Cherie A; Munn, Colin B; Bourne, David G

2017-01-01

Pervasive environmental stressors on coral reefs are attributed with shifting the competitive balance in favor of alternative dominants, such as macroalgae. Previous studies have demonstrated that macroalgae compete with corals via a number of mechanisms, including the production of potent primary and secondary metabolites that can influence coral-associated microbial communities. The present study investigates the effects of the Pacific brown macroalga Lobophora sp. (due to the shifting nature of the Lobophora species complex, it will be referred to here as Lobophora sp.) on coral bacterial isolates, coral larvae, and the microbiome associated with the coral Porites cylindrica. Crude aqueous and organic macroalgal extracts were found to inhibit the growth of coral-associated bacteria. Extracts and fractions were also shown to inhibit coral larval settlement and cause mortality at concentrations lower (pathogenic. Macroalgae (e.g., seaweeds) can physically and chemically interact with corals, causing abrasion, bleaching, and overall stress. This study contributes to a growing body of evidence suggesting that macroalgae play a critical role in shifting the coral holobiont equilibrium, which may promote the invasion of opportunistic pathogens and cause coral mortality, facilitating additional macroalgal growth and invasion in the reef. Thus, macroalgae not only contribute to a decline in coral fitness but also influence coral reef ecosystem structure. © Crown copyright 2016.

Why is the influence of soil macrofauna on soil structure only considered by soil ecologists ?

OpenAIRE

Bottinelli, N.; Jouquet, Pascal; Capowiez, Y.; Podwojewski, Pascal; Grimaldi, Michel; Peng, X.

2015-01-01

These last twenty years have seen the development of an abundant literature on the influence of soil macrofauna on soil structure. Amongst these organisms, earthworms, termites and ants are considered to play a key role in regulating the physical, chemical and microbiological properties of soils. Due to these influential impacts, soil ecologists consider these soil macro-invertebrates as ‘soil engineers’ and their diversity and abundance are nowadays considered as relevant bioindi...

Anthropogenic nitrogen input traced by means of δ 15N values in macroalgae: Results from in-situ incubation experiments

International Nuclear Information System (INIS)

Deutsch, Barbara; Voss, Maren

2006-01-01

The macroalgae species Fucus vesiculosus (Phaeophyta), Polysiphonia sp., and Ceramium rubrum (Rhodophyta) originally grown at an unpolluted brackish site of the southern Baltic Sea were incubated for 10 and 14 days at 12 stations along a salinity gradient in a highly polluted estuary. We have expected an adaptation of the initially low δ 15 N values to the higher ones within the incubation period. In addition to the macroalgae the δ 15 N values of NO 3 - were measured to evaluate fractionation processes of the source nitrate. Inside the estuary, δ 15 N-NO 3 - values were 6.2-9.7 per mille , indicating anthropogenic nitrogen sources. The red macroalgae adequately reflected the nitrate isotope values in the surrounding waters, whereas for F. vesiculosus the results were not that clear. The reasons were assumed to be higher initial δ 15 N values of F. vesiculosus and presumably a too slow nitrogen uptake and growth rate. The method of macroalgae incubations seems suitable as a simple monitoring to study the influence of anthropogenic nitrogen loading in an estuarine environment

The effect of nutrient enrichment on the growth, nucleic acid concentrations, and elemental stoichiometry of coral reef macroalgae.

Science.gov (United States)

Reef, Ruth; Pandolfi, John M; Lovelock, Catherine E

2012-08-01

The growth rate hypothesis (GRH) links growth rates with organism elemental stoichiometry. Support for the GRH was found for many animal species, but less so for plants. This is the first study to test the GRH in macroalgae. Tropical coral reef macroalgae from three lineages, Caulerpa serrulata (Chlorophyta), Laurencia intricata (Rhodophyta), and Sargassum polyphyllum (Phaeophyceae) were grown enriched with nitrogen or phosphorous and under control conditions at Heron Island on the Great Barrier Reef, Australia. Growth rate, photosynthesis, nucleic acid composition, and elemental stoichiometry were measured. Nutrient enrichment had positive effects on photosynthetic rates and on investment in RNA. However, growth rate was not correlated with either photosynthetic rates or RNA content; thus, we did not find support for the GRH in tropical macroalgae. Macroalgae, especially L. intricata, accumulated P to very high levels (>0.6% of dry weight). The growth rate response to tissue P concentrations was unimodal. Above 0.21%, P accumulation had negative effects on growth. Nitrogen was not stored, but evidence of futile cycling was observed. The capacity to store large amounts of P is probably an adaptation to the low and patchy nutrient environment of the tropical oceans.

Effects of three macroalgae, Ulva linza (Chlorophyta), Corallina pilulifera (Rhodophyta) and Sargassum thunbergii (Phaeophyta) on the growth of the red tide microalga Prorocentrum donghaiense under laboratory conditions

Science.gov (United States)

Wang, Renjun; Xiao, Hui; Wang, You; Zhou, Wenli; Tang, Xuexi

2007-10-01

Allelopathic effects of several concentrations of fresh tissue and dry powder of three macroalgae, Ulva linza, Corallina pilulifera and Sargassum thunbergii, on the red tide microalga Prorocentrum donghaiense were evaluated in microcosms. Preliminary studies on the algicidal effects of one aqueous and four organic solvent extracts from the macroalgae on the microalga were carried out to confirm the existence of allelochemicals in the tissues of the macroalgae. The effects of macroalgal culture medium filtrate on P. donghaiense were investigated using initial or semi-continuous filtrate addition. Furthermore, the potential effects of the microalga on these three macroalgae were also tested. The results of the microcosm assay showed that the growth of P. donghaiense was strongly inhibited by using fresh tissues and dry powder of the three macroalgae. Both aqueous and methanol extracts of the macroalgae had strong growth inhibitory effects on P. donghaiense, while the other three organic solvent extracts (acetone, ether and chloroform) had no apparent effect on its growth; this suggested that the allelochemicals from these three macroalga had relatively high polarities. The three macroalgal culture medium filtrates exhibited apparent growth inhibitory effect on the microalgae under initial or semi-continuous addition, which suggested that the cells of P. donghaiense are sensitive to the allelochemicals. In contrast, P. donghaiense had no apparent effect on the growth of the macroalgae in coexistence experiment.

Diatom Control - Production of Macroalgae for Human Consumption in the Pacific Northwest

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This proposal will focus on the production of fresh macroalgae in a land-based system. This type of production system avoids the regulatory and permitting issues...

Macroalgas e seus usos – alternativas para as indústrias brasileiras

Directory of Open Access Journals (Sweden)

Bárbara Monique de Freitas Vasconcelos

2014-05-01

Full Text Available As macroalgas marinhas são divididas em três grandes grupos: algas verdes, pardas e vermelhas. Elas vêm sendo utilizadas há milênios pelos povos orientais como parte importante de sua dieta alimentar. Os teores de nutrientes diferem de acordo com o grupo aos qual pertencem, no entanto, suas características nutricionais justificam o incremento desses vegetais na alimentação humana. O alto teor proteico, o elevado conteúdo de fibras e ainda o grande número de minerais são extremamente importantes para suplementação das necessidades nutricionais humanas. No entanto, além de seu uso como alimento, as algas têm sido utilizadas como suplemento de rações para diversos animais, adubos sólidos ou líquidos, no desenvolvimento de diversos cosméticos, como xampus, hidratantes, cremes anti-idade e fontes de produtos químicos diversos, dentre os quais se destacam certas mucilagens conhecidas como ficocolóides, ou colóides de algas. Estas últimas substâncias são classificadas em três grupos básicos em função de sua estrutura química e propriedades reológicas: os ágares (ágar-ágar ou agaranas, as carragenanas e os alginatos. O objetivo deste artigo é atualizar o leitor sobre as pesquisas realizadas nos últimos anos com macroalgas marinhas, abrangendo várias áreas na qual as macroalgas tem se destacado.

Soil macrofauna community structure along a gradient of land use intensification in the humid forest zone of southern Cameroon.

NARCIS (Netherlands)

Madong à Birang,

2004-01-01

The impact of land use systems on soil macrofauna community structures is described as well as their relationships with the vegetation and soil parameters in the humid forest zone of southernCameroon

Exclusion of soil macrofauna did not affect soil quality but increases crop yields in a sub-humid tropical maize-based system

NARCIS (Netherlands)

Paul, B.K.; Vanlauwe, B.; Hoogmoed, M.; Hurisso, T.T.; Ndabamenye, T.; Terano, Y.; Ayuke, F.O.; Pulleman, M.M.

2015-01-01

Soil macrofauna such as earthworms and termites are involved in key ecosystem functions and thus considered important for sustainable intensification of crop production. However, their contribution to tropical soil and crop performance, as well as relations with agricultural management (e.g.

Effects of macroalgae, with emphasis on Sargassum spp., on coral reef recruitment processes in Martinique (French West Indies)

OpenAIRE

Thabard, Marie

2012-01-01

Many coral reef ecosystems have undergone profound ecological changes over the past decades leading sometimes to a shift from coral to macroalgal-dominated areas. In Martinique (Caribbean region), the proliferation of macroalgae is an important phenomenon. Coral reef resilience, involving reef building species recruitment, might be modified by macroalgal presence. This work aimed at understanding reef recruitment processes in areas dominated either by macroalgae, coral or intermediate, based ...

Large-Scale Agricultural Management and Soil Meso- and Macrofauna Conservation in the Argentine Pampas

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José Camilo Bedano

2016-07-01

Full Text Available Soil is the most basic resource for sustainable agricultural production; it promotes water quality, is a key component of the biogeochemical cycles and hosts a huge diversity of organisms. However, we are not paying enough attention to soil degradation produced by land use. Modern agriculture has been successful in increasing yields but has also caused extensive environmental damage, particularly soil degradation. In the Argentine Pampas, agriculturization reached a peak with the generalized use of the no-till technological package: genetically modified soybeans tolerant to glyphosate, no-till, glyphosate, and inorganic fertilizers. This phenomenon has been widely spread in the country; the no-till package has been applied in large areas and has been used by tenants in a 60%–70% of cultivated lands. Thus, those who were involved in developing management practices may not be the same as those who will face degradation issues related to those practices. Indeed, most evidence reviewed in this paper suggests that the most widely distributed practices in the Pampas region are actually producing severe soil degradation. Biological degradation is particularly important because soil biota is involved in numerous soil processes on which soil functioning relies, affecting soil fertility and productivity. For example, soil meso- and macrofauna are especially important in nutrient cycling and in soil structure formation and maintenance, and they are key components of the network that links microbial process to the scale of fields and landscapes where ecosystem services are produced. However, the knowledge of the impact of different agricultural managements on soil meso- and macrofauna in Pampas agroecosystems is far from conclusive at this stage. The reason for this lack of definite conclusions is that this area has been given less attention than in other parts of the world; the response of soil fauna to agricultural practices is complex and taxa

Response of intertidal sandy-beach macrofauna to human trampling: An urban vs. natural beach system approach.

Science.gov (United States)

Reyes-Martínez, Ma José; Ruíz-Delgado, Ma Carmen; Sánchez-Moyano, Juan Emilio; García-García, Francisco José

2015-02-01

Sandy beaches are subjected to intense stressors, which are mainly derived from the increasing pattern of beach urbanization. These ecosystems are also a magnet for tourists, who prefer these locations as leisure and holiday destinations, and such activity further increases the factors that have an adverse effect on beaches. In the study reported here the effect of human trampling on macrofauna assemblages that inhabit intertidal areas of sandy beaches was assessed using a BACI design. For this purpose, three contrasting sectors of the same beach were investigated: an urban area with a high level of visitors, a protected sector with a low density of users, and a transitional area with a high level of human occupancy. The physical variables were constant over time in each sector, whereas differences were found in the intensity of human use between sectors. Density variations and changes in the taxonomic structure of the macrofauna with time were shown by PERMANOVA analysis in the urban and transitional locations whereas the protected sector remained constant throughout the study period. The amphipod Bathyporeia pelagica appears sensitive to human trampling pressure and the use of this species as a bioindicator for these types of impact is recommended. Copyright © 2014 Elsevier Ltd. All rights reserved.

Macroalgas marinas afectadas por flotas de arrastre de camarón en el Mar Caribe de Colombia

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Lennin Flórez-Leiva

2005-07-01

en ambas sitios de estudio. La biomasa de macroalgas registradas en cada lance fue mucho menor que la registrada de camarones y descartes. La evidencia que presenta este estudio sobre la existencia de macroalgas en la captura acompañante de la flota de arrastre de camarón y la acción prolongada de esta pesquería en el mar Caribe de Colombia, indican que es urgente implementar modificaciones en las redes para disminuir su efecto abrasivo sobre los fondos.

French Brittany macroalgae screening: composition and methane potential for potential alternative sources of energy and products.

Science.gov (United States)

Jard, G; Marfaing, H; Carrère, H; Delgenes, J P; Steyer, J P; Dumas, C

2013-09-01

Macroalgae are biomass resources that represent a valuable feedstock to be used entirely for human consumption or for food additives after some extractions (mainly colloids) and/or for energy production. In order to better develop the algal sector, it is important to determine the capacity of macroalgae to produce these added-values molecules for food and/or for energy industries on the basis of their biochemical characteristics. In this study, ten macroalgae obtained from French Brittany coasts (France) were selected. The global biochemical composition (proteins, lipids, carbohydrates, fibers), the presence and characteristics of added-values molecules (alginates, polyphenols) and the biochemical methane potential of these algae were determined. Regarding its biochemical composition, Palmaria palmata is interesting for food (rich in nutrients) and for anaerobic digestion (0.279 LCH4/gVS). Saccharina latissima could be used for alginate extraction (242 g/kgTS, ratio between mannuronic and guluronic acid M/G=1.4) and Sargassum muticum for polyphenol extraction (19.8 g/kgTS). Copyright © 2013 Elsevier Ltd. All rights reserved.

Reduced cover of drifting macroalgae following nutrient reduction in Danish coastald waters

DEFF Research Database (Denmark)

Rasmussen, Jonas Ribergaard; Dromph, Karsten Mikael; Göke, Cordula

2015-01-01

conditions and environmental characteristics. The cover of drifting algae was positively related to total nitrogen concentration and Secchi depth but negatively related to exposure, salinity and mean summer temperature. The cover of drifting macroalgae showed significant declines over the past two decades...

Potential contribution of surface-dwelling Sargassum algae to deep-sea ecosystems in the southern North Atlantic

Science.gov (United States)

Baker, Philip; Minzlaff, Ulrike; Schoenle, Alexandra; Schwabe, Enrico; Hohlfeld, Manon; Jeuck, Alexandra; Brenke, Nils; Prausse, Dennis; Rothenbeck, Marcel; Brix, Saskia; Frutos, Inmaculada; Jörger, Katharina M.; Neusser, Timea P.; Koppelmann, Rolf; Devey, Colin; Brandt, Angelika; Arndt, Hartmut

2018-02-01

Deep-sea ecosystems, limited by their inability to use primary production as a source of carbon, rely on other sources to maintain life. Sedimentation of organic carbon into the deep sea has been previously studied, however, the high biomass of sedimented Sargassum algae discovered during the VEMA Transit expedition in 2014/2015 to the southern North Atlantic, and its potential as a regular carbon input, has been an underestimated phenomenon. To determine the potential for this carbon flux, a literature survey of previous studies that estimated the abundance of surface water Sargassum was conducted. We compared these estimates with quantitative analyses of sedimented Sargassum appearing on photos taken with an autonomous underwater vehicle (AUV) directly above the abyssal sediment during the expedition. Organismal communities associated to Sargassum fluitans from surface waters were investigated and Sargassum samples collected from surface waters and the deep sea were biochemically analyzed (fatty acids, stable isotopes, C:N ratios) to determine degradation potential and the trophic significance within deep-sea communities. The estimated Sargassum biomass (fresh weight) in the deep sea (0.07-3.75 g/m2) was several times higher than that estimated from surface waters in the North Atlantic (0.024-0.84 g/m2). Biochemical analysis showed degradation of Sargassum occurring during sedimentation or in the deep sea, however, fatty acid and stable isotope analysis did not indicate direct trophic interactions between the algae and benthic organisms. Thus, it is assumed that components of the deep-sea microbial food web form an important link between the macroalgae and larger benthic organisms. Evaluation of the epifauna showed a diverse nano- micro-, meio, and macrofauna on surface Sargassum and maybe transported across the Atlantic, but we had no evidence for a vertical exchange of fauna components. The large-scale sedimentation of Sargassum forms an important trophic link

Anthropogenic nitrogen input traced by means of {delta} {sup 15}N values in macroalgae: Results from in-situ incubation experiments

Energy Technology Data Exchange (ETDEWEB)

Deutsch, Barbara [Baltic Sea Research Institute, Seestr. 15, 18119 Rostock (Germany)]. E-mail: barbara.deutsch@io-warnemuende.de; Voss, Maren [Baltic Sea Research Institute, Seestr. 15, 18119 Rostock (Germany)

2006-08-01

The macroalgae species Fucus vesiculosus (Phaeophyta), Polysiphonia sp., and Ceramium rubrum (Rhodophyta) originally grown at an unpolluted brackish site of the southern Baltic Sea were incubated for 10 and 14 days at 12 stations along a salinity gradient in a highly polluted estuary. We have expected an adaptation of the initially low {delta} {sup 15}N values to the higher ones within the incubation period. In addition to the macroalgae the {delta} {sup 15}N values of NO{sub 3} {sup -} were measured to evaluate fractionation processes of the source nitrate. Inside the estuary, {delta} {sup 15}N-NO{sub 3} {sup -} values were 6.2-9.7 per mille , indicating anthropogenic nitrogen sources. The red macroalgae adequately reflected the nitrate isotope values in the surrounding waters, whereas for F. vesiculosus the results were not that clear. The reasons were assumed to be higher initial {delta} {sup 15}N values of F. vesiculosus and presumably a too slow nitrogen uptake and growth rate. The method of macroalgae incubations seems suitable as a simple monitoring to study the influence of anthropogenic nitrogen loading in an estuarine environment.

Macroalgae as a Biomass Feedstock: A Preliminary Analysis

Energy Technology Data Exchange (ETDEWEB)

Roesijadi, Guritno; Jones, Susanne B.; Snowden-Swan, Lesley J.; Zhu, Yunhua

2010-09-26

A thorough of macroalgae analysis as a biofuels feedstock is warranted due to the size of this biomass resource and the need to consider all potential sources of feedstock to meet current biomass production goals. Understanding how to harness this untapped biomass resource will require additional research and development. A detailed assessment of environmental resources, cultivation and harvesting technology, conversion to fuels, connectivity with existing energy supply chains, and the associated economic and life cycle analyses will facilitate evaluation of this potentially important biomass resource.

Variability of macrofauna distribution along a dissipative log-spiral sandy beach in Rio de Janeiro, Southeastern Brazil

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Carlos A.M. Barboza

2017-03-01

Full Text Available Log-spiral beaches display defined physical gradients alongshore. However, the majority of studies focus on the variability of a single population of macrofauna species. We aimed to investigate the variation in species distribution and in community structure along ten transects on a log-spiral beach. Principal component analysis indicated a clear physical gradient alongshore. Redundancy analysis showed that the sheltered end was related to smaller particle sizes, higher organic matter content and high densities of polychaetes. The exposed end was characterized by coarser sand, lower organic matter content and a high presence of crustaceans. Model selection indicated that the “best fit” to explain the variability in the number of individuals included grain size and beach slope. Variability of the polychaete Scolelepis squamata was best explained by grain size, slope and sediment sorting. The best model for the cirolanid Excirolana armata only included sediment sorting. The physical gradient in sediment texture and the beach slope explained more than one-third of the variability in community structure. The physical variables were also correlated with the distribution of the individual species. We showed that the physical gradient on log-spiral coasts may be an important driver of macrofauna variability, even at mesoscales and in dissipative conditions.

KAROTENOID DARI MAKROALGAE DAN MIKROALGAE: POTENSI KESEHATAN APLIKASI DAN BIOTEKNOLOGI [Carotenoids from Macroalgae and Microalgae: Health Potential, Application and Biotechnology

OpenAIRE

Leenawaty Limantara3); Budhi Prasetyo1); AB. Susanto2); Helly de Fretes1)*

2012-01-01

Algae, both micro and macroalgae, is one of the largest producers of carotenoids. The major composition of carotenoid on algae are β-carotene, astaxanthin, luthein, zeaxanthin, cryptoxanthin, and fucoxanthin which have important roles for human health. Carotenoids were produced by several microalgae species such as Dunaliella sallina, Haemotococcus pluvialis, Chlorella pyrenoidosa, Spirulina platensis, Nannnochloropsis oculata, and also from some macroalgae species such as Kappaphycus alvarez...

Profiling of the Molecular Weight and Structural Isomer Abundance of Macroalgae-Derived Phlorotannins

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Natalie Heffernan

2015-01-01

Full Text Available Phlorotannins are a group of complex polymers of phloroglucinol (1,3,5-trihydroxybenzene unique to macroalgae. These phenolic compounds are integral structural components of the cell wall in brown algae, but also play many secondary ecological roles such as protection from UV radiation and defense against grazing. This study employed Ultra Performance Liquid Chromatography (UPLC with tandem mass spectrometry to investigate isomeric complexity and observed differences in phlorotannins derived from macroalgae harvested off the Irish coast (Fucus serratus, Fucus vesiculosus, Himanthalia elongata and Cystoseira nodicaulis. Antioxidant activity and total phenolic content assays were used as an index for producing phlorotannin fractions, enriched using molecular weight cut-off dialysis with subsequent flash chromatography to profile phlorotannin isomers in these macroalgae. These fractions were profiled using UPLC-MS with multiple reaction monitoring (MRM and the level of isomerization for specific molecular weight phlorotannins between 3 and 16 monomers were determined. The majority of the low molecular weight (LMW phlorotannins were found to have a molecular weight range equivalent to 4–12 monomers of phloroglucinol. The level of isomerization within the individual macroalgal species differed, resulting in substantially different numbers of phlorotannin isomers for particular molecular weights. F. vesiculosus had the highest number of isomers of 61 at one specific molecular mass, corresponding to 12 phloroglucinol units (PGUs. These results highlight the complex nature of these extracts and emphasize the challenges involved in structural elucidation of these compounds.

MACROALGAS E QUALIDADE DA ÁGUA NA BACIA DO ALTO RIO NEGRO - MUNICÍPIO DE SÃO GABRIEL DA CACHOEIRA (AM.

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Domitila Pascoaloto

2011-01-01

Full Text Available Foram investigadas as comunidades de macroalgas do rio Negro, no município de São Gabriel da Cachoeira. Em setembro/2007 foram visitados cinco sítios amostrais, próximos à sede da cidade; em Março/2008 foram investigados oito sítios amostrais, entre a comunidade Amium (hemisfério norte e a sede da cidade (hemisfério sul; em agosto de 2008 foram investigadas as comunidades de macroalgas e a qualidade da água do rio Negro e onze afluentes, entre os rios Içana (hemisfério norte e Marie, no hemisfério sul; em abril/2009 foram coletadas macroalgas e água no rio Negro e em igarapés de água com tonalidade vermelha, na sede da cidade; em maio/2009 foram feitas coletas de água no rio Negro entre a comunidade de Cucuí, onde o rio Negro entra no Brasil e a sede do município. As águas dos locais apresentaram características típicas de rio de “água preta”: pH ácido ( 6,0 mgO2/L. As entidades ecológicas de macroalgas observadas pertenceram aos gêneros Batrachospermum Roth (Batrachospermaceae, Rhodophyta; Microspora Thuret (Microsporaceae, Chorophyta, Oedogonium Link ex Hirn (Oedogoniaceae, Chorophyta; Oscillatoria Vaucher ex Gomont (Oscillatoriaceae, Cyanophyta; Phormidium Kützing ex Gomont (Phormidiaceae, Cyanophyta; Spirogyra Link (Zygnemaceae, Chlorophyta; Tabellaria Ehrenberge ex Kützing (Fragilariophyceae, Bacillariophyta. Na sede da cidade, a macroalga mais freqüente (50% dos registros foi Spirogyra spp.. Foram encontradas macroalgas com hábitos eplilíticos e efíticos Gametófitos de Batrachospermum spp. foram observados em três sítios amostrais (em troncos ou rochas em setembro/2007, período de águas mais baixas, porém não foram encontradas macroalgas nesses locais em março/2008, quando o rio estava mais cheio. No entanto, em agosto de 2008, quando o rio também estava em período de águas altas, foram observados, em fragmentos rochosos na orla da sede do município, filamentos férteis de Batrachospermum sp

Bioremediation for coal-fired power stations using macroalgae.

Science.gov (United States)

Roberts, David A; Paul, Nicholas A; Bird, Michael I; de Nys, Rocky

2015-04-15

Macroalgae are a productive resource that can be cultured in metal-contaminated waste water for bioremediation but there have been no demonstrations of this biotechnology integrated with industry. Coal-fired power production is a water-limited industry that requires novel approaches to waste water treatment and recycling. In this study, a freshwater macroalga (genus Oedogonium) was cultivated in contaminated ash water amended with flue gas (containing 20% CO₂) at an Australian coal-fired power station. The continuous process of macroalgal growth and intracellular metal sequestration reduced the concentrations of all metals in the treated ash water. Predictive modelling shows that the power station could feasibly achieve zero discharge of most regulated metals (Al, As, Cd, Cr, Cu, Ni, and Zn) in waste water by using the ash water dam for bioremediation with algal cultivation ponds rather than storage of ash water. Slow pyrolysis of the cultivated algae immobilised the accumulated metals in a recalcitrant C-rich biochar. While the algal biochar had higher total metal concentrations than the algae feedstock, the biochar had very low concentrations of leachable metals and therefore has potential for use as an ameliorant for low-fertility soils. This study demonstrates a bioremediation technology at a large scale for a water-limited industry that could be implemented at new or existing power stations, or during the decommissioning of older power stations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Caracterización de la macrofauna edáfica en sistemas de producción intensiva de césped

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Wendy Ramírez

Full Text Available Se realizó una investigación con el objetivo de evaluar el comportamiento de la macrofauna edáfica en áreas de la finca de producción intensiva de césped, en la Estación Experimental de Pastos y Forrajes Indio Hatuey. Se evaluaron tres sistemas, con diferentes años de explotación y tres réplicas por sistema: S1: suelos con diez años o más de explotación intensiva; S2: suelos con cuatro años de explotación; y S3: suelos de condición estándar o de referencia, en los que se establecerán las parcelas para la producción intensiva de césped. En sentido general, la composición taxonómica de la macrofauna edáfica fue similar en los sistemas evaluados, y existieron diferencias en cuanto a la diversidad y equitatividad de los órdenes. Los sistemas más perturbados (S1 y S2 fueron los de menor diversidad taxonómica, con cinco unidades taxonómicas (ut, debido al monocultivo continuado de gramíneas cespitosas. Los órdenes de mayor representación en el S1 fueron Coleoptera (38,63 % y Haplotaxida (31,81 %; en el S2, Coleoptera (52,63 % y Haplotaxida (28,94 %; y en el S3, Haplotaxida (34,48 % y Lepidoptera (12,93 %. Estos resultados evidencian el potencial de la macrofauna edáfica como indicador de la calidad del suelo, y su sensibilidad ante las perturbaciones causadas por la intensidad en el uso y manejo del suelo.

The potential of freshwater macroalgae as a biofuels feedstock and the influence of nutrient availability on freshwater macroalgal biomass production

Science.gov (United States)

Yun, Jin-Ho

Extensive efforts have been made to evaluate the potential of microalgae as a biofuel feedstock during the past 4-5 decades. However, filamentous freshwater macroalgae have numerous characteristics that favor their potential use as an alternative algal feedstock for biofuels production. Freshwater macroalgae exhibit high rates of areal productivity, and their tendency to form dense floating mats on the water surface imply significant reductions in harvesting and dewater costs compared to microalgae. In Chapter 1, I reviewed the published literature on the elemental composition and energy content of five genera of freshwater macroalgae. This review suggested that freshwater macroalgae compare favorably with traditional bio-based energy sources, including terrestrial residues, wood, and coal. In addition, I performed a semi-continuous culture experiment using the common Chlorophyte genus Oedogonium to investigate whether nutrient availability can influence its higher heating value (HHV), productivity, and proximate analysis. The experimental study suggested that the most nutrient-limited growth conditions resulted in a significant increase in the HHV of the Oedogonium biomass (14.4 MJ/kg to 16.1 MJ/kg). Although there was no significant difference in productivity between the treatments, the average dry weight productivity of Oedogonium (3.37 g/m2/day) was found to be much higher than is achievable with common terrestrial plant crops. Although filamentous freshwater macroalgae, therefore, have significant potential as a renewable source of bioenergy, the ultimate success of freshwater macroalgae as a biofuel feedstock will depend upon the ability to produce biomass at the commercial-scale in a cost-effective and sustainable manner. Aquatic ecology can play an important role to achieve the scale-up of algal crop production by informing the supply rates of nutrients to the cultivation systems, and by helping to create adaptive production systems that are resilient to

Importance of the macrofauna for the feeding of young fish species from infralittoral of Arrozal - Cananeia lagoon estuarine region (25º02'S-47º56'W: Brazil

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Yoko Wakabara

1993-01-01

Full Text Available The aim of this study was to establish the importance of the macrofauna as food for young fish species that inhabit the infralittoral adjacent to the lower marsh. The sampling site is located at Arrozal, Cananéia lagoon estuarine region (25º02'S and 47º56'W and the collectings were realized monthly, during a year. The results suggest that the studied area could be considered as a nursery ground for young fish species. The local macrofauna is composed mainly by several groups of crustaceans and has a marked temporal variation. Mysids were dominant in Spring, copepods in Summer, mysids and bivalves were co-dominants in the Autumn and amphipods in Winter. Mysids, copepods, ostracods, tan aids and other epifaunal crustaceans were more consumed than other items. According to the trophic habits, the twelve fish species could be divided into three groups: the first and the third as mysids and copepods eaters respectively, and the second group with a balanced diet reflecting more than the other groups the seasonal variation of the macrofauna collected by the dredge. Benthonic and benthopelagic organisms were considered the major food source, being consumed by 75% of the analysed fish species, in Cananéia infralittoral.O objetivo do presente trabalho foi avaliar a importância da macrofauna do infralitoral, adjacente a marisma do Arrozal, região de Cananéia, na dieta alimentar de doze espécies de peixes jovens. De acordo com os resultados obtidos, a região pode ser considerada um berçário para muitas espécies de peixes. A macrofauna local é composta principalmente de crustáceos e apresenta uma acentuada variação temporal. Misidáceos foram dominantes na primavera, copépodes no verão, misidáceos e bivalves foram co-dominantes no outono e anfípodes no inverno. Misidáceos, copépodes, ostrácodes, tanaidáceos e outros crustáceos epifaunais foram mais consumidos pelos peixes macropredadores que outros itens. Os peixes capturados foram

A macroalgae-based biotechnology for water remediation: Simultaneous removal of Cd, Pb and Hg by living Ulva lactuca.

Science.gov (United States)

Henriques, Bruno; Rocha, Luciana S; Lopes, Cláudia B; Figueira, Paula; Duarte, A C; Vale, Carlos; Pardal, M A; Pereira, E

2017-04-15

Metal uptake from contaminated waters by living Ulva lactuca was studied during 6 days, under different relevant contamination scenarios. In mono-metallic solutions, with concentrations ranging from 10 to 100 μg L -1 for Hg, 10-200 μg L -1 for Cd, and 50-1000 μg L -1 for Pb, macroalgae (500 mg L -1 , d.w.) were able to remove, in most cases 93-99% of metal, allowing to achieve water quality criteria regarding both surface and drinking waters. In multi-metallic solutions, comprising simultaneously the three metals, living macroalgae still performed well, with Hg removal (c.a. 99%) not being significantly affected by the presence of Cd and Pb, even when those metals were in higher concentrations. Removal efficiencies for Cd and Pb varied between 57 and 96%, and 34-97%, respectively, revealing an affinity of U. lactuca toward metals: Hg > Cd > Pb. Chemical quantification in macroalgae, after bioaccumulation assays demonstrated that all Cd and Hg removed from solution was really bound in macroalgae biomass, while only half of Pb showed to be sorbed on the biomass. Overall, U. lactuca accumulated up to 209 μg g -1 of Hg, up to 347 μg g -1 of Cd and up to 1641 μg g -1 of Pb, which correspond to bioconcentration factors ranging from 500 to 2200, in a dose-dependent accumulation. Pseudo-first order, pseudo-second order and Elovich models showed a good performance in describing the kinetics of bioaccumulation, in the whole period of time. In the range of experimental conditions used, no mortality was observed and U. lactuca relative growth rate was not significantly affected by the presence of metals. Results represent an important contribution for developing a macroalgae-based biotechnology, applied for contaminated saline water remediation, more "green" and cost-effective than conventional treatment methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of Benthic Macrofauna as a Spatial Structuring Agent for Juvenile Haddock (Melanogrammus aeglefinus) on the Eastern Scotian Shelf, Atlantic Canada.

Science.gov (United States)

Rincón, Beatriz; Kenchington, Ellen L

2016-01-01

We examined the habitat of juvenile haddock on the eastern Scotian Shelf (off Nova Scotia, Canada) in relation to grab-sampled benthic macrofaunal invertebrate species assemblages in order to determine whether there were significant differences in benthic macrofauna between areas of historically persistent high and low juvenile haddock abundance. Our analyses were conducted over two spatial scales in each of two years: among banks (Emerald, Western and Sable Island), approximately 60 km distant from each other, and between areas of high and low juvenile haddock abundance at distances of 10 to 30 km-all in an area that had not experienced groundfishing in the decade prior to sampling. We also examined fine-scale (10s of metres) within-site variability in the macrofauna and used surficial sediment characteristics, along with hydrographic variables, to identify environmental correlates. PERMANOVA identified statistically significant differences in biomass, density and composition of the benthos associated with juvenile haddock abundance; however it was difficult to determine whether the results had biological relevance. Post hoc tests showed that these differences occurred only on Sable Island Bank where both fish and benthos may have been independently responding to sediment type which was most different there (100% sand in the area of low haddock abundance vs. 22% gravel in the area of high haddock abundance). In total, 383 benthic taxa representing 13 phyla were identified. Annelida was the most specious phylum (36.29% of taxa, representing 33 families), followed by Arthropoda (with Crustaceans, mostly Amphipoda, accounting for 25.07% of the total number of taxa). The strongest pattern in the macrofauna was expressed at the largest scale, between banks, accounting for approximately 25% of the variation in the data. Emerald Bank, deeper, warmer and saltier than the Western and Sable Island Banks, had a distinctive fauna.

Influence of Benthic Macrofauna as a Spatial Structuring Agent for Juvenile Haddock (Melanogrammus aeglefinus) on the Eastern Scotian Shelf, Atlantic Canada

Science.gov (United States)

2016-01-01

We examined the habitat of juvenile haddock on the eastern Scotian Shelf (off Nova Scotia, Canada) in relation to grab-sampled benthic macrofaunal invertebrate species assemblages in order to determine whether there were significant differences in benthic macrofauna between areas of historically persistent high and low juvenile haddock abundance. Our analyses were conducted over two spatial scales in each of two years: among banks (Emerald, Western and Sable Island), approximately 60 km distant from each other, and between areas of high and low juvenile haddock abundance at distances of 10 to 30 km–all in an area that had not experienced groundfishing in the decade prior to sampling. We also examined fine-scale (10s of metres) within-site variability in the macrofauna and used surficial sediment characteristics, along with hydrographic variables, to identify environmental correlates. PERMANOVA identified statistically significant differences in biomass, density and composition of the benthos associated with juvenile haddock abundance; however it was difficult to determine whether the results had biological relevance. Post hoc tests showed that these differences occurred only on Sable Island Bank where both fish and benthos may have been independently responding to sediment type which was most different there (100% sand in the area of low haddock abundance vs. 22% gravel in the area of high haddock abundance). In total, 383 benthic taxa representing 13 phyla were identified. Annelida was the most specious phylum (36.29% of taxa, representing 33 families), followed by Arthropoda (with Crustaceans, mostly Amphipoda, accounting for 25.07% of the total number of taxa). The strongest pattern in the macrofauna was expressed at the largest scale, between banks, accounting for approximately 25% of the variation in the data. Emerald Bank, deeper, warmer and saltier than the Western and Sable Island Banks, had a distinctive fauna. PMID:27649419

Anaerobic digestion of macroalgae: methane potentials, pre-treatment, inhibition and co-digestion

DEFF Research Database (Denmark)

Bangsø Nielsen, Henrik; Heiske, Stefan

2011-01-01

In the present study we tested four macroalgae species – harvested in Denmark – for their suitability of bioconversion to methane. In batch experiments (53 WC) methane yields varied from 132 ml g volatile solids1 (VS) for Gracillaria vermiculophylla, 152 ml g VS1 for Ulva lactuca, 166 ml g VS1...

KAROTENOID DARI MAKROALGAE DAN MIKROALGAE: POTENSI KESEHATAN APLIKASI DAN BIOTEKNOLOGI [Carotenoids from Macroalgae and Microalgae: Health Potential, Application and Biotechnology

Directory of Open Access Journals (Sweden)

Leenawaty Limantara3

2012-12-01

Full Text Available Algae, both micro and macroalgae, is one of the largest producers of carotenoids. The major composition of carotenoid on algae are β-carotene, astaxanthin, luthein, zeaxanthin, cryptoxanthin, and fucoxanthin which have important roles for human health. Carotenoids were produced by several microalgae species such as Dunaliella sallina, Haemotococcus pluvialis, Chlorella pyrenoidosa, Spirulina platensis, Nannnochloropsis oculata, and also from some macroalgae species such as Kappaphycus alvarezii, Sargassum sp, and Caulerpa sp. Carotenoids from algae has been proven as a powerful antioxidant and may prevent some degenerative diseases, cardiovascular, and cancer. Carotenoid also has been applied as a natural dye and dietary supplements. Biotechnology has been developed to increase the production of carotenoids from micro- and macroalgae. The large-scale cultivation of microalgae, either in open or closed system are shown to increase carotenoid production. During cultivation, some stress conditions can be specifically manipulated to optimize carotenoid production from microalgae.

Land use, macroalgae, and a tumor-forming disease in marine turtles.

Directory of Open Access Journals (Sweden)

Kyle S Van Houtan

Full Text Available Wildlife diseases are an increasing concern for endangered species conservation, but their occurrence, causes, and human influences are often unknown. We analyzed 3,939 records of stranded Hawaiian green sea turtles (Chelonia mydas over 28 years to understand fibropapillomatosis, a tumor-forming disease linked to a herpesvirus. Turtle size is a consistent risk factor and size-standardized models revealed considerable spatial and temporal variability. The disease peaked in some areas in the 1990s, in some regions rates remained constant, and elsewhere rates increased. Land use, onshore of where the turtles feed, may play a role. Elevated disease rates were clustered in watersheds with high nitrogen-footprints; an index of natural and anthropogenic factors that affect coastal eutrophication. Further analysis shows strong epidemiological links between disease rates, nitrogen-footprints, and invasive macroalgae and points to foraging ecology. These turtles now forage on invasive macroalgae, which can dominate nutrient rich waters and sequester environmental N in the amino acid arginine. Arginine is known to regulate immune activity, promote herpesviruses, and contribute to tumor formation. Our results have implications for understanding diseases in aquatic organisms, eutrophication, herpesviruses, and tumor formation.

In vitro Antibacterial Activities of the Marine Macroalgae\\" Laurencia Snyderiae\\" and \\"Sargassum Angustifolium\\" Against Human Pathogens

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behrouz Derakhshesh

2011-04-01

Full Text Available Background: Nowadays widespread applications of antibiotics caused to create resistant microorganisms and increased additive antibiotic resistance in all over the world. Thus, researches linked to investigate new antimicrobial agents that are produced in natural way have great significance to achieve new pharmaceutics resources. Based on many accomplished researches, some macroalgae have found to show noticeable antimicrobial and antifungal activities. Methods: In this research antimicrobial activity of organic extracts of the macroalgae "Laurencia snyderiae" and Sargassum angustifolium (which has been collected from coasts of Boushehr port was tested against 3 Gram- positive bacteria Streptococous mutans, Streptococous salivaris and Streptococous sanguis as well as 4 Gram- negative bacteria Salmonella typhi, Proteus vulgaris, Shigella flexniu and Micrococos luteus. Extraction was carried out using maceration method, methanol and chloroform extracts was obtained. Antimicrobial activities of the final extracts was tested using two methods agar disk diffusion method and serial tube dilution method (in order to determine Minimum Inhibitory Concentration (MIC. Results: Results of bioassay showed the tested macroalgae exhibited the highest antibacterial activity against Gram- negative bacteria, S. typhi and Gram- negative bacteria M. Luteus exhibited the highest resistant against algal extracts. Conclusion: red alga L. snyderiae exhibited higher antibacterial activity than brown alga S. angustifolium against tested bacteria strains.

Climate change and ocean acidification effects on seagrasses and marine macroalgae.

Science.gov (United States)

Koch, Marguerite; Bowes, George; Ross, Cliff; Zhang, Xing-Hai

2013-01-01

Although seagrasses and marine macroalgae (macro-autotrophs) play critical ecological roles in reef, lagoon, coastal and open-water ecosystems, their response to ocean acidification (OA) and climate change is not well understood. In this review, we examine marine macro-autotroph biochemistry and physiology relevant to their response to elevated dissolved inorganic carbon [DIC], carbon dioxide [CO2 ], and lower carbonate [CO3 (2-) ] and pH. We also explore the effects of increasing temperature under climate change and the interactions of elevated temperature and [CO2 ]. Finally, recommendations are made for future research based on this synthesis. A literature review of >100 species revealed that marine macro-autotroph photosynthesis is overwhelmingly C3 (≥ 85%) with most species capable of utilizing HCO3 (-) ; however, most are not saturated at current ocean [DIC]. These results, and the presence of CO2 -only users, lead us to conclude that photosynthetic and growth rates of marine macro-autotrophs are likely to increase under elevated [CO2 ] similar to terrestrial C3 species. In the tropics, many species live close to their thermal limits and will have to up-regulate stress-response systems to tolerate sublethal temperature exposures with climate change, whereas elevated [CO2 ] effects on thermal acclimation are unknown. Fundamental linkages between elevated [CO2 ] and temperature on photorespiration, enzyme systems, carbohydrate production, and calcification dictate the need to consider these two parameters simultaneously. Relevant to calcifiers, elevated [CO2 ] lowers net calcification and this effect is amplified by high temperature. Although the mechanisms are not clear, OA likely disrupts diffusion and transport systems of H(+) and DIC. These fluxes control micro-environments that promote calcification over dissolution and may be more important than CaCO3 mineralogy in predicting macroalgal responses to OA. Calcareous macroalgae are highly vulnerable to OA

Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water.

Science.gov (United States)

Ellison, Michael B; de Nys, Rocky; Paul, Nicholas A; Roberts, David A

2014-01-01

The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn) and metalloids (As and Se) in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in "clean" water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn) more rapidly than metalloids (As, Mo and Se). Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water

Directory of Open Access Journals (Sweden)

Michael B. Ellison

2014-05-01

Full Text Available The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn and metalloids (As and Se in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in “clean” water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn more rapidly than metalloids (As, Mo and Se. Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

Changes in ultrastructure and histochemistry of two red macroalgae strains of Kappaphycus alvarezii (Rhodophyta, Gigartinales), as a consequence of ultraviolet B radiation exposure.

Science.gov (United States)

Schmidt, Eder Carlos; Scariot, Lidiane Angela; Rover, Ticiane; Bouzon, Zenilda Laurita

2009-12-01

Ultraviolet radiation (UVR) affects macroalgae in many important ways, including reduced growth rate, reduction of primary productivity and changes in cell biology and ultrastructure. Among red macroalgae, Kappaphycus alvarezii is of economic interest by its production of kappa carrageenan. Only a few reports have examined the changes in macroalgae ultrastructure and cell biology resulting from UVB radiation exposure. Therefore, we examined two strains of K. alvarezii (green and red) exposed to UVB for 3 h per day during 28 days and then processed them for histochemical and electron microscopy analysis. Reaction with Toluidine Blue showed an increase in the thickness of the cell wall and Periodic Acid-Schiff stain showed a decrease in the number of starch grains. UVBR also caused changes in the ultrastructure of cortical and subcortical cells, which included increased thickness of the cell wall and number of free ribosomes and plastoglobuli, reduced intracellular spaces, changes in the cell contour, and destruction of chloroplast internal organization. Based on these lines of evidence, it was evident by the ultrastructural changes observed that UVBR negatively affects intertidal macroalgae and, by extension, their economic viability.

Soil macrofauna (invertebrates of Kazakhstanian Stipa lessingiana dry steppe

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Bragina Tatyana М.

2016-12-01

Full Text Available Stipa lessingiana steppes used to be prevalent on the dry Trans-Ural denudation plains, particularly, on the Sub-Ural and the Turgay Plateau. But, most of them have been lost because they were plowed up during the Virgin Land campaign in the second part of 20th century. This paper presents a detailed study of the faunistic composition and the structure of soil-dwelling invertebrate communities (macrofauna of a temperate-dry bunch feather grass steppe in the Turgai Plateau (Northern-Turgai physical-geographical province of steppe Kazakhstan, Kostanay Oblast. The study site is located in the territory of the Naurzum State Nature Reserve, a part of the UNESCO World Heritage site “Saryarka Steppe and Lakes of Northern Kazakhstan”, where remnants of Virgin S. lessingiana steppes have been preserved to the present day. This region is the driest and most continental in climate of all the dry steppes of Kazakhstan. The total abundance and biomass of soil invertebrate communities in the investigated site were lower than in the northern and western steppe areas. Soil invertebrates are among the major components that determine the functioning of terrestrial natural ecosystems.

Production of liquid biofuels (biodiesel and bioethanol) from brown marine macroalgae Padina tetrastromatica

International Nuclear Information System (INIS)

Ashokkumar, Veeramuthu; Salim, Mohd Razman; Salam, Zainal; Sivakumar, Pandian; Chong, Cheng Tung; Elumalai, Sanniyasi; Suresh, Veeraperumal; Ani, Farid Nasir

2017-01-01

Highlights: • Integrated concept of biofuels production from brown macroalgae P. tetrastromatica. • The activation energy was determined as Ea = 34.314 kJ mol"−"1. • Brown marine alga produced 7.8% of biodiesel by acid and alkali transesterification. • The fuel properties of Padina biodiesel meet the ASTM specifications. • Spent biomass of Padina yields 16.1% of bioethanol after fermentation process. - Abstract: In this study, an integrated biomass conversion concept of producing liquid biofuels from brown marine macroalga Padina tetrastromatica was investigated. The algal biomass was collected from the Mandapam coastal region and processed under laboratory. Various parameters were studied to extract crude lipids from the biomass. A kinetic study was conducted for extracting the lipids from the biomass, which follows the first order kinetics and the lipid yield was 8.15 wt.%. The activation energy; Ea = 34.314 kJ mol"−"1 and their thermodynamic parameters were determined. Since the crude algal lipids contain high amount of free fatty acids, a sequential transesterification technique was examined and 7.8% of biodiesel (78 mg/g algal biomass) yield was obtained. The biodiesel was analyzed by "1H and "1"3C–NMR spectroscopy and the conversion yield was estimated. Further, the biodiesel fuel properties were investigated and found that all the features fit the required ASTM D6751 specification limits. The residual biomass after lipid extraction was further explored for bioethanol production through the anaerobic fermentation process. The ethanol yield obtained after saccharification and fermentation were estimated and 161 mg/g residue biomass was reported. The theoretical yield of conversion of hydrolysate to bioethanol was estimated and found to be 83.4%. Therefore, this study demonstrates that macroalga P. tetrastromatica biomass has great potential to produce liquid biofuels such as biodiesel and bioethanol.

Ultrasound assisted methods for enhanced extraction of phycobiliproteins from marine macro-algae, Gelidium pusillum (Rhodophyta).

Science.gov (United States)

Mittal, Rochak; Tavanandi, Hrishikesh A; Mantri, Vaibhav A; Raghavarao, K S M S

2017-09-01

Extraction of phycobiliproteins (R-phycoerythrin, R-PE and R-phycocyanin, R-PC) from macro-algae is difficult due to the presence of large polysaccharides (agar, cellulose etc.) present in the cell wall which offer major hindrance for cell disruption. The present study is aimed at developing most suitable methodology for the primary extraction of R-PE and R-PC from marine macro-algae, Gelidium pusillum(Stackhouse) Le Jolis. Such extraction of phycobiliproteins by using ultrasonication and other conventional methods such as maceration, maceration in presence of liquid nitrogen, homogenization, and freezing and thawing (alone and in combinations) is reported for the first time. Standardization of ultrasonication for different parameters such as ultrasonication amplitude (60, 90 and 120µm) and ultrasonication time (1, 2, 4, 6, 8 and 10mins) at different temperatures (30, 35 and 40°C) was carried out. Kinetic parameters were estimated for extraction of phycobiliproteins by ultrasonication based on second order mass transfer kinetics. Based on calorimetric measurements, power, ultrasound intensity and acoustic power density were estimated to be 41.97W, 14.81W/cm 2 and 0.419W/cm 3 , respectively. Synergistic effect of ultrasonication was observed when employed in combination with other conventional primary extraction methods. Homogenization in combination with ultrasonication resulted in an enhancement in efficiency by 9.3% over homogenization alone. Similarly, maceration in combination with ultrasonication resulted in an enhancement in efficiency by 31% over maceration alone. Among all the methods employed, maceration in combination with ultrasonication resulted in the highest extraction efficiency of 77 and 93% for R-PE and R-PC, respectively followed by homogenization in combination with ultrasonication (69.6% for R-PE and 74.1% for R-PC). HPLC analysis was carried out in order to ensure that R-PE was present in the extract and remained intact even after processing

Sewage pollution in Negril, Jamaica: effects on nutrition and ecology of coral reef macroalgae

Science.gov (United States)

Lapointe, B. E.; Thacker, K.; Hanson, C.; Getten, L.

2011-07-01

Coral reefs in the Negril Marine Park (NMP), Jamaica, have been increasingly impacted by nutrient pollution and macroalgal blooms following decades of intensive development as a major tourist destination. A baseline survey of DIN and SRP concentrations, C:N:P and stable nitrogen isotope ratios (δ15N) of abundant reef macroalgae on shallow and deep reefs of the NMP in 1998 showed strong P-limitation and evidence of increasing sewage pollution. In 1999, a sewage collection and treatment project began diverting wastewater from the resort and urban areas to a pond system that discharged partially-treated effluent into the South Negril River (SNR). These sewage discharges significantly increased concentrations of NH{4/+} and SRP (N:P ˜13) in the SNR, which flows into Long Bay and around Negril's "West End". Concentrations of SRP, the primary limiting nutrient, were higher on shallow reefs of the West End in 2001 compared to 1998. Stable nitrogen isotope ratios (δ15N) of abundant reef macroalgae on both shallow and deep reefs of the West End in 2002 were significantly higher than baseline values in 1998, indicating an escalating impact of sewage nitrogen pollution over this timeframe. The increased nutrient concentrations and δ15N enrichment of reef macroalgae correlated with blooms of the chlorophyte Chaetomorpha linum in shallow waters of Long Bay and Codium isthmocladum and Caulerpa cupressoides on deep reefs of the West End. Sewage treatment systems adjacent to coral reefs must include nutrient removal to ensure that DIN and SRP concentrations, after dilution, are below the low thresholds noted for these oligotrophic ecosystems.

Distribution of vascular plants and macroalgae along salinity and elevation gradients in Oregon tidal marshes

Science.gov (United States)

Sea level rise due to global climate change may affect the spatial distribution of plants and macroalgae within tidal estuaries. We present preliminary results from on-going research in Oregon to determine how these potential abiotic drives correlate with the presence or absence...

Evaluation of impacts of climate change and local stressors on the biotechnological potential of marine macroalgae: a brief theoretical discussion of likely scenarios

Directory of Open Access Journals (Sweden)

Paulo A. Horta

2012-08-01

Full Text Available Climate change can be associated with variations in the frequency and intensity of extreme temperatures and precipitation events on the local and regional scales. Along coastal areas, flooding associated with increased occupation has seriously impacted products and services generated by marine life, in particular the biotechnological potential that macroalgae hold. Therefore, this paper analyzes the available information on the taxonomy, ecology and physiology of macroalgae and discusses the impacts of climate change and local stress on the biotechnological potential of Brazilian macroalgae. Based on data compiled from a series of floristic and ecological works, we note the disappearance in some Brazilian regions of major groups of biotechnological interest. In some cases, the introduction of exotic species has been documented, as well as expansion of the distribution range of economically important species. We also verify an increase in the similarities between the Brazilian phycogeographic provinces, although they still remain different. It is possible that these changes have resulted from the warming of South Atlantic water, as observed for its surface in southeastern Brazilian, mainly during the winter. However, unplanned urbanization of coastal areas can also produce similar biodiversity losses, which requires efforts to generate long-term temporal data on the composition, community structure and physiology of macroalgae.

Small-scale experimental contamination with diesel oil does not affect the recolonization of Sargassum (Fucales fronds by vagile macrofauna

Directory of Open Access Journals (Sweden)

Henrique Grande

2012-04-01

Full Text Available Coastal regions are subject to various forms of environmental impacts, such as spills of crude oil and associated products, with a wide range of effects on benthic biodiversity. This study characterized the patterns of recolonization of the macrofauna associated with the brown alga Sargassum cymosum(C. Agardh, on fronds contaminated by diesel oil in a small-scale field experiment. We collected 40 fronds of S. cymosum from an algal bed in southeastern Brazil and defaunated each frond by immersion in fresh water. Half of the fronds were then immersed in seawater (control group and the other half in a mixture of 50% diesel oil and 50% seawater (impacted group. The test fronds were returned to the algal bed, and natural recolonization took place over a period of 12 days. Samples of the vagile macrofauna were taken randomly at three-day intervals over the course of the recolonization period. No significant differences in the densities of most taxa were found between the impact treatment (IG and control treatment (CG. At the end of the recolonization period (day 12, the faunal composition of the treated fronds was very similar to the natural conditions, indicating a high rate of community recovery and suggesting that benthic associations can be rather resilient to diesel-oil impacts on a small scale.

Temporal pattern in the bloom-forming macroalgae Chaetomorpha linum and Ulva pertusa in seagrass beds, Swan Lake lagoon, North China

International Nuclear Information System (INIS)

Zhang, Xiaomei; Zhou, Yi; Liu, Peng; Wang, Feng; Liu, Bingjian; Liu, Xujia; Xu, Qiang; Yang, Hongsheng

2014-01-01

Highlights: • We conducted an annual survey of bloom-forming macroalgae in a lagoon. • C. linum biomass reached 1712 ± 780 g DW m −2 at the northern part of the lagoon. • Macroalgae δ 15 N values indicated a land-based source of N enrichment to the blooms. • High nutrient concentrations near the river mouth supported the blooms. • C. linum blooms induced the loss of seagrasses and benthic filter feeders. - Abstract: Seagrasses that are distributed over a large area of the Swan Lake, Weihai, China, support a productive ecosystem. In recent years, however, frequent macroalgal blooms have changed the ecosystem structure and threatened the seagrasses. To understand the bloom-forming macroalgae we conducted a yearly field survey of Swan Lake. Results indicated that the macroalgae Chaetomorpha linum and Ulva pertusa both exhibited a much higher productivity and attained a greater maximum biomass (of 1712 ± 780 g DW m −2 and 1511 ± 555 g DW m −2 , respectively) than was the case for the seagrasses. The mean annual atomic ratios of C/N, C/P and N/P in C. linum were 14.31 ± 4.45, 402.82 ± 130.25, and 28.12 ± 2.08, respectively. The δ 15 N values (11.09 ± 0.91‰ for C. linum; 9.27 ± 2.83‰ for U. pertusa) indicated a land-based source of N enrichment to the macroalgal blooms. High concentrations of nitrogen and phosphorus in the lagoon, particularly near the river mouth, supported the blooms

Bioaccumulation of heavy metals by the flora and benthic macrofauna of the Bouregreg estuary wetland

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Khamar M.

2018-01-01

Full Text Available Estuarine systems account for a high proportion of wetlands in Morocco due to the development of the river system. These estuarine and coastal Moroccan environments are as rich in fauna and flora as their European equivalents and present much originality. However, these coastal areas are generally highly urbanized and industrialized, and therefore subject to domestic and industrial discharges. The Bouregreg Estuary represents a good example of this situation, in view of this pollution (organic, chemical and biological and the absence of fresh water supply upstream of the estuary after the dam was built, is increasingly unable of restoring the equilibrium of this ecosystem. This tide can instead ensure the polluting discharge downstream or upstream. Metallic contamination affects the different compartments of the estuarine ecosystem (sediment, water and benthic species (fauna and flora. The objective of this study is to assess the accumulation and bioaccumulation of five heavy metals (Cu, Fe, Zn, Cr and Pb at the sediment level of two dominant plant species (Artiplex portulacoides and Sarcocornia fructicosa and three species of benthic macrofauna (Scrobicularia plana, Venerupis decussata and Hediste diversicolor from the wetland of this estuary. This work will enable us to clearly understand the nutritional relationships between plant, animal, water and sediment species. The results of the analysis revealed that bioaccumulation varies from one species to another and from one metal to another. Thus, the levels of Lead and Chromium at Sarcocornia fructicosa are higher than those found at Artiplex portulacoides. Nevertheless, the latter accumulates better the other metals: Cu, Zn and Fe. While, the macrofauna shows a fairly large variation depending on the life style and sensitivity of species. Thus, Hediste diversicolor showed high levels of the various metals analyzed compared to Scrobicularia plana and Venerupis decussata.

Pretreatment of the macroalgae Chaetomorpha linum for the production of bioethanol - Comparison of five pretreatment technologies

DEFF Research Database (Denmark)

Schultz-Jensen, Nadja; Thygesen, Anders; Thomsen, Sune Tjalfe

2013-01-01

-assisted pretreatment (PAP) and ball milling (BM), to determine effects of the pretreatment methods on the conversion of C. linum into ethanol by simultaneous saccharification and fermentation (SSF). WO and BM showed the highest ethanol yield of 44. g ethanol/100. g glucan, which was close to the theoretical ethanol......A qualified estimate for pretreatment of the macroalgae Chaetomorpha linum for ethanol production was given, based on the experience of pretreatment of land-based biomass. C. linum was subjected to hydrothermal pretreatment (HTT), wet oxidation (WO), steam explosion (STEX), plasma...... yield of 57. g ethanol/100. g glucan. A 64% higher ethanol yield, based on raw material, was reached after pretreatment with WO and BM compared with unpretreated C. linum, however 50% of the biomass was lost during WO. Results indicated that the right combination of pretreatment and marine macroalgae...

Diversidad de macroalgas asociada con un manto de rodolitos tropical de Brasil

OpenAIRE

Amado-Filho, GM; Maneveldt, GW; Pereira-Filho, GH; Manso, RCC; Bahia, RG.; Barros-Barreto, MB; Guimarães, SMPB

2010-01-01

Se describen las poblaciones de las macroalgas submareales predominantemente tropicales que crecen sobre rodolitos entre 4 y 18 m de profundidad en la parte sur del estado de Espirito Santo (Brasil). Muestreos cualitativos y cuantitativos revelaron comunidades ricas en especies de algas, incluyendo 167 especies. Tres especies de rodofitas son nuevas adiciones a la flora marina de Brasil (Lithothamnion muelleri, Scinaia aborealis y Mesophyllum engelhartii). Las marcadas diferencias estacionale...

Recovery of benthic macrofauna from chronic pollution in the sea area off a refinery plant, southwest Finland

Energy Technology Data Exchange (ETDEWEB)

Leppakoski, E J; Lindstrom, L S

1978-05-01

Quantitative field studies on benthic sublittoral macrofauna near an oil refinery in southwestern Finland before and after the installation of a new wastewater treatment plant that reduced the amount of oil and liquid effluents are detailed. The number of species and species diversity increased during the first and second year after pollution abatement at the stations close to the former outflows. Postabatement succession is discussed. The recovery from chronic oil pollution and the degree of ecological damage caused by previous continuous discharge of oil is discussed. (1 diagram, 10 graphs, 4 maps, 33 references, 3 tables)

Contribution of residual proteins to the thermomechanical performance of cellulosic nanofibrils isolated from green macroalgae

Science.gov (United States)

Jiaqi Guo; Khan Mohammad Ahsan Uddin; Karl Mihhels; Wenwen Fang; Päivi Laaksonen; J. Y. Zhu; Orlando J. Rojas

2017-01-01

Cellulosic nanofibrils (CNFs) were isolated from one of the most widespread freshwater macroalgae, Aegagropila linnaei. The algae were first carboxylated with a recyclable dicarboxylic acid, which facilitated deconstruction into CNFs via microfluidization while preserving the protein component. For comparison, cellulosic fibrils were also isolated by chemical treatment...

Accumulation of Cu and Zn from antifouling paint particles by the marine macroalga, Ulva lactuca

International Nuclear Information System (INIS)

Turner, Andrew; Pollock, Heather; Brown, Murray T.

2009-01-01

The marine macroalga, Ulva lactuca, has been exposed to different concentrations of antifouling paint particles (4-200 mg L -1 ) in the presence of a fixed quantity of clean estuarine sediment and its photosynthetic response and accumulation of Cu and Zn monitored over a period of 2 days. An immediate (<2 h) toxic effect was elicited under all experimental conditions that was quantitatively related to the concentration of contaminated particles present. Likewise, the rate of leaching of both Cu and Zn was correlated with the concentration of paint particles added. Copper accumulation by the alga increased linearly with aqueous Cu concentration, largely through adsorption to the cell surface, but significant accumulation of Zn was not observed. Thus, in coastal environments where boat maintenance is practiced, discarded antifouling paint particles are an important source of Cu, but not Zn, to U. lactuca. - The marine macroalga, Ulva lactuca, is able to accumulate Cu but not Zn from discarded antifouling paint particles.

Accumulation of Cu and Zn from antifouling paint particles by the marine macroalga, Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Turner, Andrew, E-mail: aturner@plymouth.ac.u [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Pollock, Heather [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Brown, Murray T. [School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

2009-08-15

The marine macroalga, Ulva lactuca, has been exposed to different concentrations of antifouling paint particles (4-200 mg L{sup -1}) in the presence of a fixed quantity of clean estuarine sediment and its photosynthetic response and accumulation of Cu and Zn monitored over a period of 2 days. An immediate (<2 h) toxic effect was elicited under all experimental conditions that was quantitatively related to the concentration of contaminated particles present. Likewise, the rate of leaching of both Cu and Zn was correlated with the concentration of paint particles added. Copper accumulation by the alga increased linearly with aqueous Cu concentration, largely through adsorption to the cell surface, but significant accumulation of Zn was not observed. Thus, in coastal environments where boat maintenance is practiced, discarded antifouling paint particles are an important source of Cu, but not Zn, to U. lactuca. - The marine macroalga, Ulva lactuca, is able to accumulate Cu but not Zn from discarded antifouling paint particles.

Modelling Macroalgae Productivity In An Estuary. A Biorremediation To Nutrient Discharges In The Ecosystems.

Science.gov (United States)

Alvera-Azcárate, A.; Ferreira, J. G.; Nunes, J. P.

Enhanced nutrient load to estuaries and coastal waters due to anthropogenic activities is damaging aquatic ecosystems, resulting in water pollution and eutrophication prob- lems. It is important to quantify the production of photosynthetic organisms, as they play an important role in controlling nitrogen removal and nitrogen fluxes between the sediments and the water column. In turbid estuaries, such as those on the NE Atlantic coast of Europe, benthic primary producers such as macroalgae may play an important part in carbon fixation and nutrient removal, since pelagic production is often strongly light-limited. Estuarine seaweeds are primarily located in intertidal areas, which are characterised by shallow waters and strong tidal currents. Due to high concentrations of suspended particulate matter in the water column, light is rapidly attenuated, limiting macroal- gae production during part of the tidal cycle. An accurate representation of sediment dynamics is essential for the determination of the light energy available for the algae, which is a key factor in reliable primary production estimates. In tidal flats, the sedi- ment dynamics is made more complex by the formation of tidal pools during low tide, where water quickly becomes clear, allowing more light to penetrate through the water column. In the present work a model is developed to calculate macroalgae production in the intertidal areas of estuaries, considering the factors mentioned above. The model is tested for the Tagus estuary (Portugal), and a Gross Primary Production of 3300 g m-2 y-1 was obtained. That results in a total nitrogen removal of 440 gN m-2 y-1. The results show that the macroalgae community plays an impor- tant role in the nitrogen cycle in estuaries and nutrient export to the open sea, acting as a biorremediation for the increased nutrient loading problem.

Demineralization of Sargassum spp. Macroalgae Biomass: Selective Hydrothermal Liquefaction Process for Bio-Oil Production

Energy Technology Data Exchange (ETDEWEB)

Díaz-Vázquez, Liz M., E-mail: limdiaz@uprrp.edu; Rojas-Pérez, Arnulfo; Fuentes-Caraballo, Mariela; Robles, Isis V. [Department of Chemistry, University of Puerto Rico Río Piedras Campus, San Juan, PR (United States); Jena, Umakanta [Bioenergy Laboratory, Desert Research Institute, Reno, NV (United States); Das, K. C. [College of Engineering, University of Georgia, Athens, GA (United States)

2015-02-11

Algae biomasses are considered a viable option for the production of biofuel because of their high yields of oil produced per dry weight. Brown macroalgae Sargassum spp. are one of the most abundant species of algae in the shores of Puerto Rico. Its availability in large quantity presents a great opportunity for use as a source of renewable energy. However, high ash content of macroalgae affects the conversion processes and the quality of resulting fuel products. This research studied the effect of different demineralization treatments of Sargassum spp. biomass, subsequent hydrothermal liquefaction (HTL), and bio-oil characterization. Demineralization constituted five different treatments: nanopure water, nitric acid, citric acid, sulfuric acid, and acetic acid. Performance of demineralization was evaluated by analyzing both demineralized biomass and HTL products by the following analyses: total carbohydrates, proteins, lipids, ash content, caloric content, metals analysis, Fourier transform infrared-attenuated total reflectance spectroscopy, energy dispersive spectroscopy, scanning electron microscopy, and GCMS analysis. HTL of Sargassum spp. before and after citric acid treatment was performed in a 1.8 L batch reactor system at 350°C with a holding time of 60 min and high pressures (5–21 MPa). Demineralization treatment with nitric acid was found the most effective in reducing the ash content of the macroalgae biomass from 27.46 to 0.99% followed by citric acid treatment that could reduce the ash content to 7%. Citric acid did not show significant leaching of organic components such as carbohydrates and proteins, and represented a less toxic and hazardous option for demineralization. HTL of untreated and citric acid treated Sargassum spp. resulted in bio-oil yields of 18.4 ± 0.1 and 22.2 ± 0.1% (ash-free dry basis), respectively.

Demineralization of Sargassum spp. Macroalgae Biomass: Selective Hydrothermal Liquefaction Process for Bio-Oil Production

International Nuclear Information System (INIS)

Díaz-Vázquez, Liz M.; Rojas-Pérez, Arnulfo; Fuentes-Caraballo, Mariela; Robles, Isis V.; Jena, Umakanta; Das, K. C.

2015-01-01

Algae biomasses are considered a viable option for the production of biofuel because of their high yields of oil produced per dry weight. Brown macroalgae Sargassum spp. are one of the most abundant species of algae in the shores of Puerto Rico. Its availability in large quantity presents a great opportunity for use as a source of renewable energy. However, high ash content of macroalgae affects the conversion processes and the quality of resulting fuel products. This research studied the effect of different demineralization treatments of Sargassum spp. biomass, subsequent hydrothermal liquefaction (HTL), and bio-oil characterization. Demineralization constituted five different treatments: nanopure water, nitric acid, citric acid, sulfuric acid, and acetic acid. Performance of demineralization was evaluated by analyzing both demineralized biomass and HTL products by the following analyses: total carbohydrates, proteins, lipids, ash content, caloric content, metals analysis, Fourier transform infrared-attenuated total reflectance spectroscopy, energy dispersive spectroscopy, scanning electron microscopy, and GCMS analysis. HTL of Sargassum spp. before and after citric acid treatment was performed in a 1.8 L batch reactor system at 350°C with a holding time of 60 min and high pressures (5–21 MPa). Demineralization treatment with nitric acid was found the most effective in reducing the ash content of the macroalgae biomass from 27.46 to 0.99% followed by citric acid treatment that could reduce the ash content to 7%. Citric acid did not show significant leaching of organic components such as carbohydrates and proteins, and represented a less toxic and hazardous option for demineralization. HTL of untreated and citric acid treated Sargassum spp. resulted in bio-oil yields of 18.4 ± 0.1 and 22.2 ± 0.1% (ash-free dry basis), respectively.

Demineralization of Sargassum spp. macroalgae biomass: selective hydrothermal liquefaction process for bio-oil production

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Liz M Díaz-Vázquez

2015-02-01

Full Text Available Algae biomasses are considered a viable option for the production of biofuel because of their high yields of oil produced per dry weight. Brown macroalgae Sargassum spp. are one of the most abundant species of algae in the shores of Puerto Rico. Its availability in large quantity presents a great opportunity for use as a source of renewable energy. However, high ash content of macroalgae affects the conversion processes and the quality of resulting fuel products. This research studied the effect of different demineralization treatments of Sargassum spp. biomass, subsequent hydrothermal liquefaction (HTL and bio-oil characterization. Demineralization constituted five different treatments: nanopure water, nitric acid, citric acid, sulfuric acid, and acetic acid. Performance of demineralization was evaluated by analyzing both demineralized biomass and HTL products by the following analyses: total carbohydrates, proteins, lipids, ash content, caloric content, metals analysis, Fourier Transform Infrared - Attenuated Total Reflectance (FTIR-ATR Spectroscopy, Energy Dispersive Spectroscopy (EDS, Scanning Electron Microscopy (SEM, and GCMS analysis. HTL of Sargassum spp. before and after citric acid treatment, was performed in a 1.8 L batch reactor system at 350°C with a holding time of 60 min and high pressures (5-21 MPa. Demineralization treatment with nitric acid was found the most effective in reducing the ash content of the macroalgae biomass from 27.46% to 0.99% followed by citric acid treatment that could reduce the ash content to 7%. Citric acid did not show significant leaching of organic components such as carbohydrates and proteins, and represented a less toxic and hazardous option for demineralization. HTL of untreated and citric acid treated Sargassum spp. resulted in bio-oil yields of 18.4±0.1 % and 22.2±0.1 % (ash free dry basis, respectively.

Nutrient and metal pollution of the eastern Gulf of Finland coastline: Sediments, macroalgae, microbiota

International Nuclear Information System (INIS)

Gubelit, Yulia; Polyak, Yulia; Dembska, Grazyna; Pazikowska-Sapota, Grazyna; Zegarowski, Lukasz; Kochura, Dmitry; Krivorotov, Denis; Podgornaya, Elena; Burova, Olga; Maazouzi, Chafik

2016-01-01

The anthropogenic pollution along the coastline of the eastern Gulf of Finland was studied through a range of methods, including analyses of metal contamination in water, surface sediments, accumulated algal biomass and its correlation with resistant microbiota. According to concentrations, the main pollutants in water were copper and manganese. Influence of Nuclear Power Plant was remarkable in adjacent areas and was expressed in high concentrations of molybdenum, nickel, copper and other elements in the water. Relatively high concentrations of copper, lead and zinc were found in sediments. Microbial tolerance appeared to be correlated with the concentration of the metals in sediments. Higher tolerance levels were found in sediment samples from more polluted stations. Macroalgae, which were massively developed in the coastal zone, had shown high level of metal bioaccumulation. Analyses of carbon, nitrogen and phosphorus content of algal tissues allowed the estimation of additional nutrient loading from accumulated decaying algal biomass on the coastal zone of the eastern Gulf of Finland. Mass development of algae in coastal area may contribute to accumulation of organic matter and associated metals. In our study the highest metal concentrations in sediments were found at the sites with dense and continuous layer of fresh and decaying macroalgal biomass, accompanied by hypoxic conditions. Also our study has shown that accumulated biomass may be a significant source of nutrients in the coastal ecosystem. - Highlights: • We studied heavy metal pollution in the coastline of the eastern Gulf of Finland. • Sediments, water, mass macroalgae and microbiota were included into analyses. • Eutrophication and nutrient loading remain the main problem of the studied area. • Macroalgae contribute to accumulation of organic matter, nutrient, and heavy metal. • Pollution in the studied area is caused by a combination of different factors.

Nutrient and metal pollution of the eastern Gulf of Finland coastline: Sediments, macroalgae, microbiota

Energy Technology Data Exchange (ETDEWEB)

Gubelit, Yulia, E-mail: Gubelit@list.ru [Zoological Institute of the Russian Academy of Sciences, St. Petersburg (Russian Federation); Polyak, Yulia [Scientific Research Center for Ecological Safety of the Russian Academy of Sciences, St. Petersburg (Russian Federation); Dembska, Grazyna; Pazikowska-Sapota, Grazyna; Zegarowski, Lukasz [Maritime Institute in Gdansk, Department of Environmental Protection, Gdansk (Poland); Kochura, Dmitry; Krivorotov, Denis; Podgornaya, Elena; Burova, Olga [Research Institute of Hygiene, Occupational Pathology and Human Ecology (RIHOPHE), Federal Medical Biological Agency, St. Petersburg (Russian Federation); Maazouzi, Chafik [Université Claude Bernard Lyon 1, Laboratoire d' Écologie des Hydrosystèmes Naturels et Anthropisés (LEHNA), Lyon (France)

2016-04-15

The anthropogenic pollution along the coastline of the eastern Gulf of Finland was studied through a range of methods, including analyses of metal contamination in water, surface sediments, accumulated algal biomass and its correlation with resistant microbiota. According to concentrations, the main pollutants in water were copper and manganese. Influence of Nuclear Power Plant was remarkable in adjacent areas and was expressed in high concentrations of molybdenum, nickel, copper and other elements in the water. Relatively high concentrations of copper, lead and zinc were found in sediments. Microbial tolerance appeared to be correlated with the concentration of the metals in sediments. Higher tolerance levels were found in sediment samples from more polluted stations. Macroalgae, which were massively developed in the coastal zone, had shown high level of metal bioaccumulation. Analyses of carbon, nitrogen and phosphorus content of algal tissues allowed the estimation of additional nutrient loading from accumulated decaying algal biomass on the coastal zone of the eastern Gulf of Finland. Mass development of algae in coastal area may contribute to accumulation of organic matter and associated metals. In our study the highest metal concentrations in sediments were found at the sites with dense and continuous layer of fresh and decaying macroalgal biomass, accompanied by hypoxic conditions. Also our study has shown that accumulated biomass may be a significant source of nutrients in the coastal ecosystem. - Highlights: • We studied heavy metal pollution in the coastline of the eastern Gulf of Finland. • Sediments, water, mass macroalgae and microbiota were included into analyses. • Eutrophication and nutrient loading remain the main problem of the studied area. • Macroalgae contribute to accumulation of organic matter, nutrient, and heavy metal. • Pollution in the studied area is caused by a combination of different factors.

Gene expression patterns of the coral Acropora millepora in response to contact with macroalgae

Science.gov (United States)

Shearer, T. L.; Rasher, D. B.; Snell, T. W.; Hay, M. E.

2012-12-01

Contact with macroalgae often causes coral mortality, but the roles of abrasion versus shading versus allelopathy in these interactions are rarely clear, and effects on gene expression are unknown. Identification of gene expression changes within corals in response to contact with macroalgae can provide insight into the mode of action of allelochemicals, as well as reveal transcriptional strategies of the coral that mitigate damage from this competitive interaction, enabling the coral to survive. Gene expression responses of the coral Acropora millepora after long-term (20 days) direct contact with macroalgae ( Chlorodesmis fastigiata, Dictyota bartayresiana, Galaxaura filamentosa, and Turbinaria conoides) and short-term (1 and 24 h) exposure to C. fastigiata thalli and their hydrophobic extract were assessed. After 20 days of exposure, T. conoides thalli elicited no significant change in visual bleaching or zooxanthellae PSII quantum yield within A. millepora nubbins, but stimulated the greatest alteration in gene expression of all treatments. Chlorodesmis fastigiata, D. bartayresiana, and G. filamentosa caused significant visual bleaching of coral nubbins and reduced the PSII quantum yield of associated zooxanthellae after 20 days, but elicited fewer changes in gene expression relative to T. conoides at day 20. To evaluate initial molecular processes leading to reduction of zooxanthella PSII quantum yield, visual bleaching, and coral death, short-term exposures to C. fastigiata thalli and hydrophobic extracts were conducted; these interactions revealed protein degradation and significant changes in catalytic and metabolic activity within 24 h of contact. These molecular responses are consistent with the hypothesis that allelopathic interactions lead to alteration of signal transduction and an imbalance between reactive oxidant species production and antioxidant capabilities within the coral holobiont. This oxidative imbalance results in rapid protein degradation

Analyzing redox balance in a synthetic yeast platform to improve utilization of brown macroalgae as feedstock

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C.A. Contador

2015-12-01

Full Text Available Macroalgae have high potential to be an efficient, and sustainable feedstock for the production of biofuels and other more valuable chemicals. Attempts have been made to enable the co-fermentation of alginate and mannitol by Saccharomyces cerevisiae to unlock the full potential of this marine biomass. However, the efficient use of the sugars derived from macroalgae depends on the equilibrium of cofactors derived from the alginate and mannitol catabolic pathways. There are a number of strong metabolic limitations that have to be tackled before this bioconversion can be carried out efficiently by engineered yeast cells.An analysis of the redox balance during ethanol fermentation from alginate and mannitol by Saccharomyces cerevisiae using metabolic engineering tools was carried out. To represent the strain designed for conversion of macroalgae carbohydrates to ethanol, a context-specific model was derived from the available yeast genome-scale metabolic reconstructions. Flux balance analysis and dynamic simulations were used to determine the flux distributions. The model indicates that ethanol production is determined by the activity of 4-deoxy-l-erythro-5-hexoseulose uronate (DEHU reductase (DehR and its preferences for NADH or NADPH which influences strongly the flow of cellular resources. Different scenarios were explored to determine the equilibrium between NAD(H and NADP(H that will lead to increased ethanol yields on mannitol and DEHU under anaerobic conditions. When rates of mannitol dehydrogenase and DehRNADH tend to be close to a ratio in the range 1–1.6, high growth rates and ethanol yields were predicted. The analysis shows a number of metabolic limitations that are not easily identified through experimental procedures such as quantifying the impact of the cofactor preference by DEHU reductase in the system, the low flux into the alginate catabolic pathway, and a detailed analysis of the redox balance. These results show that

Aminas biogênicas em macroalgas marinhas do Estado do Ceará, Brasil Biogenic amines in marine macroalgae of the state of Ceará, Brazil

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Daniel Barroso de Alencar

2011-06-01

Full Text Available Muitas aminas são comumente encontradas em alimentos de origem vegetal e animal, porém apenas um pequeno número é de interesse por produzirem reações adversas se ingeridas e absorvidas no organismo humano. Dentre elas, a histamina e a tiramina podem desencadear sintomas de intoxicação. As algas marinhas são amplamente consumidas pelos povos orientais, e, no Ocidente, seu consumo encontra-se em expansão. O Brasil não tem esta tradição, mas a diversidade de espécies encontradas no litoral brasileiro as torna potencialmente úteis como alimento humano. Para promovê-las com essa finalidade, são necessários estudos químicos e bioquímicos. No presente trabalho, treze espécies de macroalgas marinhas coletadas na praia do Pacheco, no município de Caucaia - CE, foram preliminarmente analisadas quanto à presença de histamina e tiramina por cromatografia líquida de alta eficiência. A identificação destas aminas biogênicas foi feita com base nos tempos de retenção dos padrões comerciais de dicloridrato de histamina e cloridrato de tiramina, comparados com aqueles correspondentes aos mesmos compostos nos extratos algais. Nenhuma das treze espécies estudadas neste trabalho apresentou histamina e/ou tiramina em quantidades capazes de provocar sintomas de intoxicação através do seu consumo.Many amines are commonly found in food of both animal and vegetable origin, however only a small number is of interest since they produce diverse reactions when ingested and absorbed by humans. Among them, histamine and tyramine can cause intoxication symptoms. Marine algae are consumed widely by the eastern civilizations, and in the West, their consumption is expanding. Brazil does not have this tradition, but the diversity of species found throughout the Brazilian coast line make marine algae potentially useful for human ingestion. For such, it is necessary to perform chemical and biochemical studies. In this study, thirteen species of

Antibacterial activity of extracts of six macroalgae from the northeastern brazilian coast

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Lima-Filho José Vitor M.

2002-01-01

Full Text Available Hexane, chloroform and ethanol extracts of six marine macroalgae (Rhodophyta and Chlorophyta from North Ceará coast (Northeast Brazil were evaluated for antibacterial activity by the single disk method. Best results were shown by the hexane extracts of Amansia multifida against enteric Gram-negative strains such as Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, S. cholerae-suis, Serratia marcescens, Vibrio cholerae and the Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus.

The effect of earthworms and other saprophagous macrofauna on soil microstructure in reclaimed and un-reclaimed post-mining sites in Central Europe

Czech Academy of Sciences Publication Activity Database

Frouz, Jan; Pižl, Václav; Tajovský, Karel

2007-01-01

Roč. 43, Suppl. 1 (2007), S184-S189 ISSN 1164-5563 R&D Projects: GA ČR GA526/01/1055; GA ČR(CZ) GA526/06/0728; GA ČR GA526/03/1259; GA AV ČR 1QS600660505 Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworms * soil macrofauna * soil microstructure Subject RIV: EH - Ecology, Behaviour Impact factor: 0.500, year: 2007

Zonation of macrofauna across sandy beaches and surf zones along the Dutch coast

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Gerard Janssen

2005-06-01

Full Text Available On nine beaches and two transects in the surf zone along the Dutch coast the presence of benthic macrofauna was studied in relation to basic abiotic characteristics. According to Short's classification system, Dutch beaches are mesotidal and dissipative (Ω = 8.6, and the RTR is low (1.52-1.27, which means that they are not tide-dominated. BSI ranged from 1.4 to 1.1 for the northern and western Dutch coasts respectively and had an overall value of 1.2. The rates of exposure of the beaches varied between 8 and 12, and are therefore regarded as sheltered to moderately exposed. The Dutch beaches display a geographical trend in beach types. Those of the Wadden Sea islands in the northern part of the Netherlands are dissipative, flat, fine-grained, and host high densities of many species of benthic macrofauna. The beaches along the western Dutch coast are less dissipative, steeper, with a higher mean grain size; the species diversity and abundance there are lower. Species diversity and abundance on the beaches increase from the high- to the low-water line. The maximum number of species was found between 0 and -1 m relative to the mean tidal level. The abundance peaks just above the mean tidal level, while the biomass reaches a maximum at the mean tidal level.     Species diversity and abundance are low in the surf zone, but increase towards deeper water. Species numbers are high and the abundance is very high in the trough between the two bars.     The relation between the diversity and abundance of macrobenthic species on the one hand, and the sediment composition, water column depth, and position between the bars on the other show a clear pattern of zonation for the beach, surf zone and near-shore: (1 a supralittoral zone with insects and air-breathing crustaceans, (2 a midshore zone, with intertidal species, (3 a lower shore zone, whose species extend into the shallow surf zone, and (4 a zone of sublittoral fauna in the trough between the

Valuable biomolecules from nine North Atlantic red macroalgae: Amino acids, fatty acids, carotenoids, minerals and metals

DEFF Research Database (Denmark)

Razi Parjikolaei, Behnaz; Bruhn, Annette; Eybye, Karin Loft

2016-01-01

In modern society, novel marine resources are scrutinized pursuing compounds of use in the medical, pharmaceutical, biotech, food or feed industry. Few of the numerous marine macroalgae are currently exploited. In this study, the contents of nutritional compounds from nine common North Atlantic r...

Herbivory on macro-algae affects colonization of beach-cast algal wrack by detritivores but not its decomposition

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Philip Eereveld

2013-05-01

Full Text Available Spatial subsidies have increasingly been considered significant sources of matter and energy to unproductive ecosystems. However, subsidy quality may both differ between subsidizing sources and vary over time. In our studies, sub-littoral herbivory by snails or isopods on red or brown macro-algae induced changes in algal tissues that affected colonization of beach-cast algal wrack by supra-littoral detritivores (amphipods. However, microbial decay and decomposition through the joint action of detritivores and microbes of algal wrack in the supra-littoral remained unaffected by whether or not red or brown algae had been fed upon by snails or isopods. Thus, herbivory on marine macro-algae affects the cross-system connection of sub-littoral and supra-littoral food webs transiently, but these effects diminish upon ageing of macro-algal wrack in the supra-littoral zone.

Nutritional and Functional Bioactivity Value of Selected Azorean Macroalgae: Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea.

Science.gov (United States)

Paiva, Lisete; Lima, Elisabete; Neto, Ana Isabel; Marcone, Massimo; Baptista, José

2017-07-01

This study presents information on the biochemical composition (dry weight basis), nutritional aspects, and angiotensin I-converting enzyme (ACE) inhibitory properties of selected macroalgae (Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea) from Azores. Moisture content was very high (83.2% to 90.0% of fresh weight). Total dietary fiber (33.7% to 41.0%) that presented a good balance of both soluble and insoluble fibers (15.5% to 19.2% and 18.2% to 21.8%, respectively) was the most abundant component in these macroalgae. Protein and ash (ranged from 15.7% to 23.4% and 10.7% to 20.7%, respectively) were the 2nd most abundant components in red and green macroalgae, respectively. Moderate soluble carbohydrate contents (14.5% to 19.8%) were found in all species. Lipid contents were low (1.0% to 4.3%), particularly in Ulva species (1.0% to 1.7%), but contained higher unsaturated fatty acids (FAs) (7.5% to 32.9% and 29.6% to 69.2% of total FA for monounsaturated fatty acid and polyunsaturated fatty acid groups, respectively) than saturated fatty acid (23.3% to 46.8% of total FA) contents. All the macroalgal proteins had high digestibility in vitro (82.2% to 89.4%, relatively to sodium caseinate), contained high quantity of essential amino acids (45.3% to 58.1% of total amino acids), but in different proportions, and were rich in aspartic and glutamic acids that together account for 17.2% to 36.2% of the total amino acids. These results suggested that regular consumption of the selected macroalgae may improve human health and revealed that they can be used for producing food supplements for human and animal nutrition and/or pharmaceuticals with potential effect on the regional economy. Furthermore, the ACE-inhibitory IC 50 values of 0.095 to 0.695 mg/mL for the <1 kDa protein hydrolysate fraction revealed a potential impact on hypertension disorder. © 2017 Institute of Food Technologists®.

Laboratory experiments examining inducible defense show variable responses of temperate brown and red macroalgae Experimentos de laboratorio para examinar las defensas inducibles muestran respuestas variables en macroalgas pardas y rojas de ambientes templados

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EVA ROTHÄUSLER

2005-12-01

Full Text Available Macroalgae can defend themselves against generalist and specialist herbivores via morphological and/or chemical traits. Herein we examined the defensive responses (via relative palatability of two brown (Lessonia nigrescens, Glossophora kunthii and two red algae (Grateloupia doryphora, Chondracanthus chamissoi from the northern-central coast of Chile against selected generalist meso-herbivores. Two laboratory experiments were conducted to investigate whether (i algae can respond generally to grazing pressure of meso-herbivores (amphipods, isopods and juvenile sea urchins and whether (ii these algal responses were inducible. In order to examine palatability and thus effectiveness of responses, feeding assays were run after each experiment using fresh algal pieces and artificial agar-based food. Lessonia nigrescens responded to amphipods but not to sea urchins, and G. kunthii showed inducible response against one species of amphipods. Grateloupia doryphora did not respond against any of the tested grazers, whereas C. chamissoi responded against one species of amphipods and the tested isopod. Our results indicate variable responses of macroalgae against selected generalist meso-herbivores and evidence of an inducible defense in the brown alga G. kunthii.Muchas macroalgas poseen la capacidad de defenderse contra herbívoros generalistas y especialistas utilizando defensas químicas y/o morfológicas. En este trabajo se examinó la respuesta de la palatabilidad ante meso-herbívoros generalistas de dos algas pardas (Lessonia nigrescens, Glossophora kunthii y dos algas rojas (Grateloupia doryphora, Chondracanthus chamissoi de la costa Norte de Chile. Se realizaron dos experimentos de laboratorio para investigar si: (i las algas pueden responder al pastoreo realizado por meso-herbivoros generalistas (anfípodos, isópodos y erizos juveniles y (ii si la respuesta de estas algas es inducible. Para examinar la palatabilidad y de esta forma la efectividad

Chemical characterization of 21 species of marine macroalgae common in Norwegian waters: benefits of and limitations to their potential use in food and feed

Science.gov (United States)

Biancarosa, Irene; Belghit, Ikram; Bruckner, Christian G; Liland, Nina S; Waagbø, Rune; Amlund, Heidi; Heesch, Svenja

2018-01-01

Abstract BACKGROUND In the past few years, much effort has been invested into developing a new blue economy based on harvesting, cultivating and processing marine macroalgae in Norway. Macroalgae have high potential for a wide range of applications, e.g. as source of pharmaceuticals, production of biofuels or as food and feed. However, data on the chemical composition of macroalgae from Norwegian waters are scant. This study was designed to characterize the chemical composition of 21 algal species. Both macro‐ and micronutrients were analysed. Concentrations of heavy metals and the metalloid arsenic in the algae were also quantified. RESULTS The results confirm that marine macroalgae contain nutrients which are relevant for both human and animal nutrition, the concentrations whereof are highly dependent on species. Although heavy metals and arsenic were detected in the algae studied, concentrations were mostly below maximum allowed levels set by food and feed legislation in the EU. CONCLUSION This study provides chemical data on a wide range of algal species covering the three taxonomic groups (brown, red and green algae) and discusses both benefits of and potential limitations to their use for food and feed purposes. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:29193189

Constancy despite variability: Local and regional macrofaunal diversity in intertidal seagrass beds

Science.gov (United States)

Boyé, Aurélien; Legendre, Pierre; Grall, Jacques; Gauthier, Olivier

2017-12-01

The importance of seagrass habitat for the diversity of benthic fauna has been extensively studied worldwide. Most of the information available is, however, about α diversity while little consideration has been given to β diversity. To fill the knowledge gaps regarding the variability of epifaunal and infaunal seagrass assemblages at large spatial and temporal scales, we scrutinized an extensive dataset covering five years of monitoring of eight intertidal Zostera marina meadows around Brittany (France). High species richness arose at the regional scale from the combination of high local diversity of the meadows and substantial among-meadows β diversity. Epifauna and infauna appeared as distinct self-communities as they displayed different spatial and temporal patterns and varied in their responses to local hydrological conditions. Infauna had higher total β diversity than epifauna due to a tighter link to the great variability of local environmental conditions in the region. Both exhibited substantial variations in species composition and community structure with variations of dominant species that were accompanied by extensive change in numerous rare species. The dominant epifaunal species were all grazers. Changes in species composition were induced mostly by species replacement and rarely by richness differences between meadows. Indeed, species richness remained within a narrow range for all seagrass beds, suggesting a potential carrying capacity for species richness of the meadows. Overall, all meadows contributed equally to the regional turnover of seagrass macrofauna, emphasizing high variability and complementarity among beds at the regional scale. The implications of this substantial within-seagrass variability for the functioning of benthic ecosystems at broad scale and for conservation purposes in habitat mosaics warrant further investigations but our results clearly advocate taking into account within-habitat variation when evaluating the diversity

Deep-sea Lebensspuren of the Australian continental margins

Science.gov (United States)

Przeslawski, Rachel; Dundas, Kate; Radke, Lynda; Anderson, Tara J.

Much of the deep sea comprises soft-sediment habitats dominated by comparatively low abundances of species-rich macrofauna and meiofauna. Although often not observed, these animals bioturbate the sediment during feeding and burrowing, leaving signs of their activities called Lebensspuren ('life traces'). In this study, we use still images to quantify Lebensspuren from the eastern (1921 images, 13 stations, 1300-2200 m depth) and western (1008 images, 11 stations, 1500-4400 m depth) Australian margins using a univariate measure of trace richness and a multivariate measure of Lebensspuren assemblages. A total of 46 Lebensspuren types were identified, including those matching named trace fossils and modern Lebensspuren found elsewhere in the world. Most traces could be associated with waste, crawling, dwellings, organism tests, feeding, or resting, but the origin of 15% of trace types remains unknown. Assemblages were significantly different between the two regions and depth profiles, with five Lebensspuren types accounting for over 95% of the differentiation (ovoid pinnate trace, crater row, spider trace, matchstick trace, mesh trace). Lebensspuren richness showed no strong relationships with depth, total organic carbon, or mud, although there was a positive correlation to chlorin index (i.e., organic freshness) in the eastern margin, with richness increasing with organic freshness. Lebensspuren richness was not related to epifauna either, indicating that epifauna may not be the primary source of Lebensspuren. Despite the abundance and distinctiveness of several traces both in the current and previous studies (e.g., ovoid pinnate, mesh, spider), their origin and distribution remains a mystery. We discuss this and several other considerations in the identification and quantification of Lebensspuren. This study represents the first comprehensive catalogue of deep-sea Lebensspuren in Australian waters and highlights the potential of Lebensspuren as valuable and often

Towards an ecological index for tropical soil quality based on soil macrofauna Em busca de um índice ecológico para a qualidade de solo tropical com base na macrofauna edáfica

Directory of Open Access Journals (Sweden)

Esperanza Huerta

2009-08-01

Full Text Available The objective of this work was to construct a simple index based on the presence/absence of different groups of soil macrofauna to determine the ecological quality of soils. The index was tested with data from 20 sites in South and Central Tabasco, Mexico, and a positive relation between the model and the field observations was detected. The index showed that diverse agroforestry systems had the highest soil quality index (1.00, and monocrops without trees, such as pineapple, showed the lowest soil quality index (0.08. Further research is required to improve this model for natural systems that have very low earthworm biomass (O objetivo deste trabalho foi construir um índice simples com base na presença/ausência de diferentes grupos da macrofauna edáfica para auxiliar na determinação da qualidade ecológica dos solos. O índice foi testado com dados de 20 locais do sul e centro do Estado de Tabasco, México, e foi observada uma correlação positiva entre o dados gerados pelo modelo e pelas observações de campo. O índice de qualidade de solo mostrou que diversos sistemas agroflorestais tiveram a mais alta qualidade de solo (1,0 e que os monocultivos sem árvores, como o de abacaxi, apresentaram a qualidade de solo mais baixa (0,08. Este modelo precisa ser melhor desenvolvido para ser aplicado eficientemente em sistemas que apresentam naturalmente baixas densidades de minhocas (<10 g m-2 e número elevado de espécies de minhocas (5-7, como ocorre em solos de floresta tropical, cujo índice de qualidade de solo apresentou valores médios (0,5. A aplicação desse índice precisará de um guia ilustrado para os seus usuários. Mais estudos são necessários para testar o seu emprego por fazendeiros.

Cross-shelf transport of sub-thermocline nitrate by the internal tide and rapid (3-6 h) incorporation by an inshore macroalga

Science.gov (United States)

Ladah, Lydia B.; Filonov, Anatoliy; Lavín, Miguel F.; Leichter, James J.; Zertuche-González, José A.; Pérez-Mayorga, Diana M.

2012-07-01

During summer in shallow waters off Baja California, Mexico, the internal tide is a dominant thermal feature of the water column. However, its importance for sub-thermocline nutrient provision to benthic macroalgae is unknown. In order to determine if internal motions provide nutrients to macroalgae in summer, Ulva lactuca was outplanted at inshore stations for short (3 and 6 h) intervals, at the surface, 5 and 10 m depth, and tissue nitrogen content was measured before and after each deployment. Concurrently temperature, currents, and nutrients were measured using moored thermistors, current profilers, CTDs, Niskin bottles, and an in-situ UV absorbance nitrate sensor (ISUS). Discrete pulses of cool, nutrient-rich water were horizontally displaced at least 4 km on the shelf and shoaled more than 20 m depth at the semidiurnal frequency, resulting in more than a 10-fold change in the concentration of nitrate. Inshore, tissue nitrogen of Ulva outplants increased significantly during longer exposures to this cool water. At this site, the semidiurnal signal dominates water column temperature fluctuations from April to November, with summer showing the greatest cooling (up to 5 °C) in a one-hour period. We estimated that 11% of the days of a year show internal waves that would cause a significant change in nutrient availability to macroalgae at 5 m depth. This study supports the hypothesis that nitrate can reach and be rapidly incorporated by inshore macroalgae such as Ulva through transport forced by the internal tide, and that even very short (internal tide provides a significant, yet understudied, high frequency nutrient source to inshore primary producers, particularly in summer.

Spatial distribution pattern analysis of subtidal macroalgae assemblages by a non-destructive rapid assessment method

Science.gov (United States)

Guinda, Xabier; Juanes, José Antonio; Puente, Araceli; Echavarri-Erasun, Beatriz

2012-01-01

The extensive field work carried out over the last century has allowed the worldwide description of general distribution patterns and specific composition of rocky intertidal communities. However, the information concerning subtidal communities on hard substrates is more recent and scarce due to the difficulties associated with working in such environments. In this work, a non-destructive method is applied to the study and mapping of subtidal rocky bottom macroalgae assemblages on the coast of Cantabria (N Spain) which is quick, easy and economical. Gelidium corneum and Cystoseira baccata were the dominant species, however, the composition and coverage of macroalgae assemblages varied significantly at different locations and depth ranges. The high presence of Laminaria ochroleuca and Saccorhiza polyschides, characteristic of colder waters, shows the transitional character of this coastal area. The results obtained throughout this study have been very useful to the application of the European Water Framework Directive (WFD 2000/60/EC) and could be of great interest for the future conservation and management of these ecosystems (e.g. Habitats Directive 92/43/EEC).

Effects of organic loading rate on biogas production from macroalgae: Performance and microbial community structure.

Science.gov (United States)

Sun, Meng-Ting; Fan, Xiao-Lei; Zhao, Xiao-Xian; Fu, Shan-Fei; He, Shuai; Manasa, M R K; Guo, Rong-Bo

2017-07-01

Macroalgae biomass has been considered as a promising feedstock for biogas production. In order to improve the efficiency of anaerobic digestion (AD) of macroalgae, semi-continuous fermentation was conducted to examine the effects of organic loading rate (OLR) on biogas production from Macrocystis pyrifer. Results showed that, under OLRs of 1.37, 2.74, 4.12 and 6.85kgVS substrate /(m 3 ·d), the average unit biogas yields were 438.9, 477.3, 480.1 and 188.7mL/(gVS substrate d), respectively. It indicated that biogas production was promoted by the increased OLR in an appropriate range while inhibited by the OLR beyond the appropriate range. The investigation on physical-chemical parameters revealed that unfavorable VFAs concentration, pH and salinity might be the main causes for system failure due to the overrange OLR, while the total phenols failed to reach the inhibitory concentration. Microbial community analysis demonstrated that several bacterial and archaeal phyla altered with increase in OLR apparently. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bioremediation of reject water from anaerobically digested waste water sludge with macroalgae (Ulva lactuca, Chlorophyta).

Science.gov (United States)

Sode, Sidsel; Bruhn, Annette; Balsby, Thorsten J S; Larsen, Martin Mørk; Gotfredsen, Annemarie; Rasmussen, Michael Bo

2013-10-01

Phosphorus and biologically active nitrogen are valuable nutrient resources. Bioremediation with macroalgae is a potential means for recovering nutrients from waste streams. In this study, reject water from anaerobically digested sewage sludge was successfully tested as nutrient source for cultivation of the green macroalgae Ulva lactuca. Maximal growth rates of 54.57±2.16% FW d(-1) were achieved at reject water concentrations equivalent to 50 μM NH4(+). Based on the results, the growth and nutrient removal was parameterised as function of NH4(+) concentration a tool for optimisation of any similar phycoremediation system. Maximal nutrient removal rates of 22.7 mg N g DW(-1) d(-1) and 2.7 mg P g DW(-1) d(-1) were achieved at reject water concentrations equivalent to 80 and 89 μM NH4(+), respectively. A combined and integrated use of the produced biomass in a biorefinery is thought to improve the feasibility of using Ulva for bioremediation of reject water. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Trophic categorization in the Rías Baixas (NW Spain: nutrients in water and in macroalgae

Directory of Open Access Journals (Sweden)

Rubén Villares

2006-03-01

Full Text Available Marine eutrophication caused by an excess supply of nutrients is a serious problem in many coastal areas throughout the world. In the present study we used the capacity of macroalgae (Ulva and Enteromorpha to integrate the nutrient regime of a water body in order to examine the trophic categorization in the embayments studied. We found that the trophic categorization established based on nutrient levels in macroalgae differed from that established based on concentrations in the water. The waters of the innermost areas of the inlets were the most nutrient enriched; the algae appeared to be more affected by specific local conditions and did not display the gradient of decreasing nutrient concentrations from inner to outer areas that was observed in the water samples. The lack of correspondence between nutrients in the water and in the algae in the present study may have been due to the heterogeneous nutrient conditions found in coastal areas, so that the intertidal algae did not adequately reflect the nutrient levels of the inner zones of the embayments under study.

Efecto de diferentes usos de la tierra en la composición y la abundancia de la macrofauna edáfica, en la provincia de Matanzas

Directory of Open Access Journals (Sweden)

Y García

Full Text Available Se evaluó el efecto de cuatro sistemas de uso de la tierra en la riqueza y la abundancia de la macrofauna edáfica, durante el periodo lluvioso (junio-octubre del año 2011, en los municipios de Colón, Calimete y Perico (provincia de Matanzas, Cuba. El muestreo de la macrofauna se realizó según la Metodología del Programa de Investigación Internacional Biología y Fertilidad del Suelo Tropical (TSBF. Los sistemas evaluados fueron: cultivos varios (suelos con 10 años -o más- de explotación intensiva, fincas agropecuarias (suelos con más de cinco años de explotación, con laboreo mínimo y con fertilización orgánica e inorgánica, silvopastoril (suelos con más de 10 años de explotación y con una carga global de ganado vacuno entre 1,7 y 1,8 UGM/ha y pastizal (suelos con más de 10 años de explotación y con una carga global de ganado vacuno entre 1,3 y 1,5 UGM/ha. Los mayores valores de densidad y biomasa se obtuvieron en los sistemas menos perturbados, siguiendo el gradiente: silvopastoril-pastizal-fincas agropecuarias-cultivos varios. La densidad solo fue sensible en los sistemas donde hubo un contraste en cuanto a la diversidad y los estratos de vegetación. La biomasa reflejó los cambios en los diferentes usos y en el manejo de los suelos. Se demostró que los distintos usos de la tierra, así como el grado de perturbación e intensidad del manejo, influyeron en la composición y la abundancia de la macrofauna edáfica.

Mechanisms of metal tolerance in marine macroalgae, with emphasis on copper tolerance in Chlorophyta and Rhodophyta.

Science.gov (United States)

Moenne, Alejandra; González, Alberto; Sáez, Claudio A

2016-07-01

Green and red macroalgae are closely related organisms, and with terrestrial plants, and constitute the base of marine food webs in coastal ecosystems. Green and red seaweeds, as all living organisms, require essential metals, such as copper, iron, zinc, which can act as co-factors for several proteins and enzymes; however, these metals in excess can induce stress and impair cell viability. Most important negative effects of metal excess are related to the induction of an oxidative stress condition, characterized by the over-accumulation of Reactive Oxygen Species (ROS). In this respect, copper, abundant in wastewaters disposed to coastal environments from domestic and industrial activities, has been one of the most studied metals. Different investigations have provided evidence that green and red macroalgae display several defenses against copper excess to prevent, or at least reduce, stress and damage, among which are cellular exclusion mechanisms, synthesis of metal-chelating compounds, and the activation of the antioxidant system. Most important defense mechanisms identified in green and red seaweed involve: metal-binding to cell wall and epibionts; syntheses of metallothioneins and phytochelatins that accumulate in the cytoplasm; and the increase in the activity of antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, glutathione peroxidase and catalase, and greater production of antioxidant metabolites as glutathione and ascorbate in organelles and the cytoplasm. In this review, we go through historical records, latest advances, and pending tasks aiming to expand our current knowledge on defense mechanisms to copper excess in green and red macroalgae, with emphasis on biochemical and molecular aspects. Copyright © 2016 Elsevier B.V. All rights reserved.

Macrofauna on rocky substrates in the Forsmark biotest basin. March 1984 - March 1985

International Nuclear Information System (INIS)

Snoeijs, P.; Mo, K.

1987-09-01

The Forsmark biotest basin, situated on the Swedish east coast, is an artificial offshore brackish lake, through which the cooling water is channelled from the Forsmark nuclear power plant to the Bothnian Sea. The biotest basin is up to 10 0 C warmer than the sea surrounding it, and has no ice cover in winter. There is an artificial, fast current in a large part of the basin. Macrofauna on stones in the hydrolittoral belt was sampled at 11 sites in- and outside the basin every third week during one year. The numbers of individuals per m 2 for each taxon were counted. Diversity indices and dominance-diversity curves were computed for each site on the basis of pooled data for the cold season, and for the rest of the year. In total 66 taxa were distinguished in the species lists, of which 3 are sessile, the rest free-living. (orig./DG)

Asexual propagation in the coral reef macroalga Halimeda (Chlorophyta, Bryopsidales) : production, dispersal and attachment of small fragments

NARCIS (Netherlands)

Walters, LJ; Coyer, JA; Hunter, CL; Beach, KS; Vroom, PS

2002-01-01

Siphonous, green macroalgae of the genus Halimeda are ubiquitous and ecologically important in tropical and subtropical marine environments. It has been hypothesized that the abundance of Halimeda on coral reefs is in part due to the ability of this genus to propagate asexually via vegetative

Prebiotics from marine macroalgae for human and animal health applications.

LENUS (Irish Health Repository)

O'Sullivan, Laurie

2010-01-01

The marine environment is an untapped source of bioactive compounds. Specifically, marine macroalgae (seaweeds) are rich in polysaccharides that could potentially be exploited as prebiotic functional ingredients for both human and animal health applications. Prebiotics are non-digestible, selectively fermented compounds that stimulate the growth and\\/or activity of beneficial gut microbiota which, in turn, confer health benefits on the host. This review will introduce the concept and potential applications of prebiotics, followed by an outline of the chemistry of seaweed polysaccharides. Their potential for use as prebiotics for both humans and animals will be highlighted by reviewing data from both in vitro and in vivo studies conducted to date.

Chemical characterization of 21 species of marine macroalgae common in Norwegian waters: benefits of and limitations to their potential use in food and feed.

Science.gov (United States)

Biancarosa, Irene; Belghit, Ikram; Bruckner, Christian G; Liland, Nina S; Waagbø, Rune; Amlund, Heidi; Heesch, Svenja; Lock, Erik-Jan

2018-03-01

In the past few years, much effort has been invested into developing a new blue economy based on harvesting, cultivating and processing marine macroalgae in Norway. Macroalgae have high potential for a wide range of applications, e.g. as source of pharmaceuticals, production of biofuels or as food and feed. However, data on the chemical composition of macroalgae from Norwegian waters are scant. This study was designed to characterize the chemical composition of 21 algal species. Both macro- and micronutrients were analysed. Concentrations of heavy metals and the metalloid arsenic in the algae were also quantified. The results confirm that marine macroalgae contain nutrients which are relevant for both human and animal nutrition, the concentrations whereof are highly dependent on species. Although heavy metals and arsenic were detected in the algae studied, concentrations were mostly below maximum allowed levels set by food and feed legislation in the EU. This study provides chemical data on a wide range of algal species covering the three taxonomic groups (brown, red and green algae) and discusses both benefits of and potential limitations to their use for food and feed purposes. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Thermal pyrolysis characteristics of macroalgae Cladophora glomerata.

Science.gov (United States)

Gao, Wenhua; Chen, Kefu; Zeng, Jinsong; Xu, Jun; Wang, Bin

2017-11-01

The Cladophora glomerata (C. glomerata) is a kind of widely distributed macroalgae in the freshwater ecosystems. It primarily consists of carbohydrates that can be converted into biofuel by pyrolysis. In this study, thermogravimetric analysis (TGA) was used to investigate the thermal behavior and kinetics of C. glomerata during the pyrolysis process. The results showed that heating rates slightly affect the decomposition properties of C. glomerata; with the heating rates increasing, the maximum peak of weight loss rate shifted to higher temperatures. The activation energies of C. glomerata pyrolysis reaction were 244.25 and 238.07kJ/mol, respectively, as calculated by Friedman and Kissinger-Akahira-Sunose (KAS) methods. The pre-exponential factor and reaction order were determined by Coats-Redfern model, and applied to simulate the pyrolysis process of C. glomerata. The model calculated data and experimental data were consistent. This study could provide theoretical supports for designing C. glomerata conversion processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Wastewater use in agriculture and potential effects on meso and macrofauna soil

Directory of Open Access Journals (Sweden)

Dinéia Tessaro

2016-06-01

Full Text Available ABSTRACT: The use of wastewater in agriculture has been practiced on an increasing scale over the past decades because of its fertilizing potential and the reduction in demand for surface water and groundwater. However, this practice may bring harm when performed without planning, not respecting the capacity of the soil to recycle organic waste. The most common problems are contamination of surface and groundwater via leaching and runoff, as well as accumulation of nutrients and potentially polluting elements that compromise chemical, physical and biological characteristics of the soil. The biological compartment, represented by the micro, meso and macrofauna, plays an important role in nutrient cycling, decomposition of organic matter, particle movement and transport of materials at different depths, helping to maintain soil physical and chemical characteristics. In this sense, this paper aims to discuss the effect of using different kinds of wastewater in agriculture on soil biology, highlighting strengths and weaknesses, as well as emphasizing the need to conduct investigations that enhance the positive aspects of wastewater use associated with edaphic processes.

Potential effects of climate change on the water level, flora and macro-fauna of a large neotropical wetland.

Science.gov (United States)

Úbeda, Bárbara; Di Giacomo, Adrian S; Neiff, Juan José; Loiselle, Steven A; Poi, Alicia S Guadalupe; Gálvez, José Ángel; Casco, Silvina; Cózar, Andrés

2013-01-01

Possible consequences of climate change in one of the world's largest wetlands (Ibera, Argentina) were analysed using a multi-scale approach. Climate projections coupled to hydrological models were used to analyse variability in wetland water level throughout the current century. Two potential scenarios of greenhouse gas emissions were explored, both resulting in an increase in the inter-annual fluctuations of the water level. In the scenario with higher emissions, projections also showed a long-term negative trend in water-level. To explore the possible response of biota to such water-level changes, species-area relationships of flora and aerial censuses of macro-fauna were analysed during an extraordinary dry period. Plant species richness at the basin scale was found to be highly resistant to hydrological changes, as the large dimension of the wetland acts to buffer against the water-level variations. However, local diversity decreased significantly with low water levels, leading to the loss of ecosystem resilience to additional stressors. The analysis of macro-fauna populations suggested that wetland provides refuge, in low water periods, for the animals with high dispersal ability (aquatic and migratory birds). On the contrary, the abundance of animals with low dispersal ability (mainly herbivorous species) was negatively impacted in low water periods, probably because they are required to search for alternative resources beyond the wetland borders. This period of resource scarcity was also related to increased mortality of large mammals (e.g. marsh deer) around water bodies with high anthropogenic enrichment and cyanobacteria dominance. The synergy between recurrent climatic fluctuations and additional stressors (i.e. biological invasions, eutrophication) presents an important challenge to the conservation of neotropical wetlands in the coming decades.

Accumulation of alkaline earth metals by the green macroalga Bryopsis maxima.

Science.gov (United States)

Takahashi, Shigekazu; Aizawa, Kyoko; Nakamura, Saki; Nakayama, Katsumi; Fujisaki, Shingo; Watanabe, Soichiro; Satoh, Hiroyuki

2015-04-01

Twenty-five days after the disaster at the Fukushima Daiichi nuclear power plant in 2011, we collected samples of the green macroalga Bryopsis maxima from the Pacific coast of Japan. Bryopsis maxima is a unicellular, multinuclear, siphonous green macroalga. Radiation analysis revealed that B. maxima emitted remarkably high gamma radiation of (131)I, (134)Cs, (137)Cs, and (140)Ba as fission products of (235)U. Interestingly, B. maxima contained naturally occurring radionuclides derived from (226)Ra and (228)Ra. Analysis of element content revealed that B. maxima accumulates many ocean elements, especially high quantities of the alkaline earth metals Sr (15.9 g per dry-kg) and Ba (3.79 g per dry-kg), whereas Ca content (12.5 g per dry-kg) was lower than that of Sr and only 61 % of the mean content of 70 Japanese seaweed species. Time-course analysis determined the rate of radioactive (85)Sr incorporation into thalli to be approximately 0.13 g Sr per dry-kg of thallus per day. Subcellular fractionation of B. maxima cells showed that most of the (85)Sr was localized in the soluble fraction, predominantly in the vacuole or cytosol. Given that (85)Sr radioactivity was permeable through a dialysis membrane, the (85)Sr was considered to be a form of inorganic ion and/or bound with a small molecule. Precipitation analysis with sodium sulfate showed that more than 70% of the Sr did not precipitate as SrSO4, indicating that a proportion of the Sr may bind with small molecules in B. maxima.

Low-molecular-weight organoiodine and organobromine compounds released by polar macroalgae--the influence of abiotic factors.

Science.gov (United States)

Laturnus, F; Giese, B; Wiencke, C; Adams, F C

2000-01-01

The influence of temperature, light, salinity and nutrient availability on the release of volatile halogenated hydrocarbons was investigated in the Antarctic red macroalgal species Gymnogongrus antarcticus Skottsberg. Compared to standard culture condition, an increase in the release rates of iodocompounds was generally found for the exposure of the alga to altered environmental conditions. Macroalgae exhibited higher release rates after adaptation for two months to the changed factors, than after short-term exposure. Monitoring the release rates during a 24 h incubation period (8.25 h light, 15.75 h darkness) showed that changes between light and dark periods had no influence on the release of volatile halocarbons. Compounds like bromoform and 1-iodobutane exhibited constant release rates during the 24 h period. The formation mechanisms and biological role of volatile organohalogens are discussed. Although marine macroalgae are not considered to be the major source of biogenically-produced volatile organohalogens, they contribute significantly to the bromine and iodine cycles in the environment. Under possible environmental changes like global warming and uncontrolled entrophication of the oceans their significance may be increase.

Anaerobic co-digestion of Tunisian green macroalgae Ulva rigida with sugar industry wastewater for biogas and methane production enhancement.

Science.gov (United States)

Karray, Raida; Karray, Fatma; Loukil, Slim; Mhiri, Najla; Sayadi, Sami

2017-03-01

Ulva rigida is a green macroalgae, abundantly available in the Mediterranean which offers a promising source for the production of valuable biomaterials, including methane. In this study, anaerobic digestion assays in a batch mode was performed to investigate the effects of various inocula as a mixture of fresh algae, bacteria, fungi and sediment collected from the coast of Sfax, on biogas production from Ulva rigida. The results revealed that the best inoculum to produce biogas and feed an anaerobic reactor is obtained through mixing decomposed macroalgae with anaerobic sludge and water, yielding into 408mL of biogas. The process was then investigated in a sequencing batch reactor (SBR) which led to an overall biogas production of 375mL with 40% of methane. Further co-digestion studies were performed in an anaerobic up-flow bioreactor using sugar wastewater as a co-substrate. A high biogas production yield of 114mL g -1 VS added was obtained with 75% of methane. The co-digestion proposed in this work allowed the recovery of natural methane, providing a promising alternative to conventional anaerobic microbial fermentation using Tunisian green macroalgae. Finally, in order to identify the microbial diversity present in the reactor during anaerobic digestion of Ulva rigida, the prokaryotic diversity was investigated in this bioreactor by the denaturing gradient gel electrophoresis (DGGE) method targeting the 16S rRNA gene. Copyright © 2016 Elsevier Ltd. All rights reserved.

An evaluation of the toxicity and bioaccumulation of cisplatin in the marine environment using the macroalga, Ulva lactuca

International Nuclear Information System (INIS)

Easton, Cecilia; Turner, Andrew; Sewell, Graham

2011-01-01

The cytotoxic drug, cisplatin (cis-PtCl 2 (NH 3 ) 2 ), has been added to cultures of the marine macroalga, Ulva lactuca, under various experimental conditions. Both accumulation and internalisation over a 48 h period was greater when cisplatin was added to coastal sea water (salinity = 33) from a distilled water solution than when added to either sea water or estuarine water (salinity = 16.5) from a saline solution. This effect is attributed to the greater abundance of the more reactive monoaqua complex (cis-PtCl(OH 2 )(NH 3 ) 2 + ) in the distilled water solution and kinetic constraints on its conversion back to cis-PtCl 2 (NH 3 ) 2 in sea water. Despite its mode of action at the cellular level, cisplatin added up to concentrations of 150 nM did not incur a measurable reduction in the efficiency of photochemical energy conversion under any of experimental conditions tested. - Highlights: → This study is the first to examine the biogeochemistry and toxicity of a cytotoxic drug in the marine environment. → Cisplatin is accumulated and internalised by the marine macroalga, Ulva lactuca. → Accumulation is greater when the drug is administered from a distilled water solution than from a saline solution. → Results are consistent with the greater abundance of the more reactive aquated complexes in pure water. → Cisplatin is not phytotoxic to the alga over the concentration range (<150 nM) studied. - The cytotoxic drug, cisplatin, is accumulated and internalised by the marine macroalga, Ulva lactuca, but is not phytotoxic up to concentrations of 150 nM

Salt tolerance of estuarine benthic macroalgae in the Kattegat-Baltic Sea area

DEFF Research Database (Denmark)

Larsen, A.; Sand-Jensen, K.

2006-01-01

Tolerance of benthic marine macroalgae to low salinities is believed to be a main determinant of their vertical distribution across the marine coastline and their horizontal distribution from oceanic regions into low-saline bays, fjords and estuaries. Salt tolerance should also be important......, Denmark (salinity: 16 psu, tide 10 cm) to maintain photosynthesis after 4 days exposure to declining salinities (16 to 0 psu). Overall, the algal community had a high short-term tolerance to low salinities because 35 of 44 species maintained more than half the photosynthetic capacity at salinities lower...

Influence of macroalgae diversity on radionuclide and heavy metal accumulation in Bulgarian Black Sea ecosystems

International Nuclear Information System (INIS)

Nonova, Tz.; Strezov, A.; Ivanov, D.; Stankov, D.

2006-01-01

Radionuclides and toxic metals in Black Sea green, brown and red macroalgae were investigated using Low-level Gamma Spectroscopy and Atomic Absorption Spectrometry AAS (FAAS, ETAAS). All algae samples were collected along the whole Bulgarian coast during the period 1996 - 2004. The obtained data show that radionuclide and metal concentrations depend on the macrophytes type and are higher in red Ceramium species. Tendencies in the concentration pollutants variations during the studied period are examined and all data give information about different macrophytic species ability to accumulate certain elements from one and the same sampling location The possibilities to use Chlorophyta, Phaeophyta and Rhodophyta algae phylums as bioindicators in marine environment are investigated. All obtained results show that use of macroalgae reduces the need of complex studies on chemical speciation of aquatic contaminants and makes algae valuable indicators for the seawater quality assessment. Higher levels are obtained at the northern part of the Black Sea due to seawater current circulation, originating from Danube, Dnyeper and Dnester river outflow and also at the southern part of the coast. All data show that there is no serious contamination along the Bulgarian coast

Subtidal eelgrass/macroalgae surveys for the proposed breakwaters at the US Coast Guard Station at Ediz Hook, Washington, March 1993

Energy Technology Data Exchange (ETDEWEB)

Shreffler, D.K. [Battelle/Marine Sciences Lab., Sequim, WA (US)

1993-05-01

In 1993, the US Coast Guard proposed to construct two breakwaters and a debris boom to protect its existing pier and moored vessels inside Ediz Hook in Port Angeles Harbor, Washington. To assist the US Army Corps of Engineers -- Seattle District in determining the potential environmental impacts of the proposed breakwaters, Battelle/Marine Sciences Laboratory performed subtidal SCUBA surveys as specified in the Washington Department of Fisheries intermediate eelgrass/macroalgae habitat survey guidelines. The objectives of the subtidal surveys were to (1) quantify the shoot densities of eelgrass; (2) provide percent cover estimates for non-eelgrass macroalgae species; (3) develop a site map indicating the qualitative distribution of eelgrass/macroalgae species, substrate characterization, approximate depth contours, and the approximate location of the proposed project features; and (4) document the time and date of the surveys, turbidity/visibility, presence of invertebrate/vertebrate species, and anecdotal observations pertinent to habitat characterization of the project site. A total of 14 dives along 12 transects (T1--T12) were successfully completed between March 15 and March 17, 1993. Eelgrass was observed on all of the transects except T7 and T8 at the western debris barrier and T12 along the waterward margin of the existing T-pier. The vicinity of the proposed east breakwater had the highest eelgrass shoot densities (up to 89 shoots/m{sup 2}) observed by the divers. Macroalgae and invertebrate species diversity were also highest at the east breakwater site. The low eelgrass densities observed at the west debris barrier site (0 to 14 shoots/m{sup 2}) can be attributed mostly to the lack of suitable substrate. The existing layer of wood debris armoring the bottom at the west project site currently limits, and in the areas of heaviest deposition probably precludes, the growth of eelgrass. As was expected, no eelgrass was observed at the south breakwater site.

Prebiotics from Marine Macroalgae for Human and Animal Health Applications

Science.gov (United States)

O’Sullivan, Laurie; Murphy, Brian; McLoughlin, Peter; Duggan, Patrick; Lawlor, Peadar G.; Hughes, Helen; Gardiner, Gillian E.

2010-01-01

The marine environment is an untapped source of bioactive compounds. Specifically, marine macroalgae (seaweeds) are rich in polysaccharides that could potentially be exploited as prebiotic functional ingredients for both human and animal health applications. Prebiotics are non-digestible, selectively fermented compounds that stimulate the growth and/or activity of beneficial gut microbiota which, in turn, confer health benefits on the host. This review will introduce the concept and potential applications of prebiotics, followed by an outline of the chemistry of seaweed polysaccharides. Their potential for use as prebiotics for both humans and animals will be highlighted by reviewing data from both in vitro and in vivo studies conducted to date. PMID:20714423

Homogalactanas sulfatadas da macroalga verde Codium isthmocladum: aspectos estruturais e farmacológicos

OpenAIRE

Farias, Eduardo Henrique Cunha de [UNIFESP

2011-01-01

Galactanas e o termo utilizado para designar polissacarideos que contem galactose. Homogalactanas sulfatadas, SG 1 e SG 2, foram extraidas de macroalga marinha verde Codium isthmocladum apos proteolise, fracionamento por acetona a frio e cromatografia de troca-ionica. A massa molecular foi determinada por cromatografia de gel-filtracao em HPLC e deteccao por indice de refracao e UV, sendo que SG 1 apresenta massa molecular media ao redor de 12 kDa e SG 2 de 15,0 kDa. Analises estruturais empr...

HPLC fucoxanthin profiles of a microalga, a macroalga and a pure fucoxanthin standard

Directory of Open Access Journals (Sweden)

Su Chern Foo

2017-02-01

Full Text Available Data in this article illustrate representative fucoxanthin chromatograms of a microalga, Chaetoceros calcitrans; a macroalga, Saccharina japonica and; a pure fucoxanthin standard. High performance liquid chromatography (HPLC eluted fucoxanthin at the 7.008±0.024th min. This data article refers to the research article ‘‘Antioxidant capacities of fucoxanthin-producing algae as influenced by their carotenoid and phenolic contents’’ Foo et al. [1]; where a more comprehensive data interpretation and analysis is explained.

Recent developments on biofuels production from microalgae and macroalgae

DEFF Research Database (Denmark)

Kumar, Kanhaiya; Ghosh, Supratim; Angelidaki, Irini

2016-01-01

and infrastructure requirement. Hydrogen production by microalgae through biophotolysis seems interesting as it directly converts the solar energy into hydrogen. However, the process has not been scaled-up till today. Hydrothermal liquefaction (HTL) is more promising due to handling of wet biomass at moderate......Biofuels from algae are considered as promising alternatives of conventional fossil fuels, as they can eliminate most of the environmental problems. The present study focuses on all the possible avenues of biofuels production through biochemical and thermochemical conversion methods in one place......, bringing together both microalgae and macroalgae on the same platform. It provides a brief overview on the mechanism of different biofuel production from algae. Factors affecting the biofuel process and the associated challenges have been highlighted alongwith analysis of techno-economic study available...

Potential effects of climate change on the water level, flora and macro-fauna of a large neotropical wetland.

Directory of Open Access Journals (Sweden)

Bárbara Úbeda

Full Text Available Possible consequences of climate change in one of the world's largest wetlands (Ibera, Argentina were analysed using a multi-scale approach. Climate projections coupled to hydrological models were used to analyse variability in wetland water level throughout the current century. Two potential scenarios of greenhouse gas emissions were explored, both resulting in an increase in the inter-annual fluctuations of the water level. In the scenario with higher emissions, projections also showed a long-term negative trend in water-level. To explore the possible response of biota to such water-level changes, species-area relationships of flora and aerial censuses of macro-fauna were analysed during an extraordinary dry period. Plant species richness at the basin scale was found to be highly resistant to hydrological changes, as the large dimension of the wetland acts to buffer against the water-level variations. However, local diversity decreased significantly with low water levels, leading to the loss of ecosystem resilience to additional stressors. The analysis of macro-fauna populations suggested that wetland provides refuge, in low water periods, for the animals with high dispersal ability (aquatic and migratory birds. On the contrary, the abundance of animals with low dispersal ability (mainly herbivorous species was negatively impacted in low water periods, probably because they are required to search for alternative resources beyond the wetland borders. This period of resource scarcity was also related to increased mortality of large mammals (e.g. marsh deer around water bodies with high anthropogenic enrichment and cyanobacteria dominance. The synergy between recurrent climatic fluctuations and additional stressors (i.e. biological invasions, eutrophication presents an important challenge to the conservation of neotropical wetlands in the coming decades.

A study of extraction and characterization of alginates obtained from brown macroalgae Sargassum duplicatum and Sargassum crassifolium from Indonesia

Directory of Open Access Journals (Sweden)

Decky J. Indrani

2013-06-01

Full Text Available Background: Worldwide commercially available alginate have been used for tissue engineering purposes. The macroalgae Sargassum obtained from Indonesia have been used for various purposes, however, they have not been applied for tissue engineering scaffolds. Purpose: This study was aimed to extract alginate from the macroalgae Sargassum from Indonesia sea and to characterize in morphology, chemical element and functional groups. Methods: Macroalgae Sargassum duplicatum (S. Duplicatum and Sargassum crassifolium (S. Crassifolium were collected from Banten, Indonesia. Extraction of alginates were carried out using the alkaline extraction procedure. Scanning electron microscopy as well as X-ray Fluorescence and Fouirer Transform Infra-Red spectroscopy were used to characterize the extracted powders. Obtained data from the extracted powders were compared to those of the commercially available alginate. Results: Extraction using the alkaline method has resulted in S.duplicatum and S.crassifolium alginate powders. Alginate particles were suggested as irregular shapes with various dimension. Element components were mainly Na and Ca, whereas, minor elements were considered as negative impurities. COO- and C-O-C groups were evident in the finger print regio. The characteristics of Alginates extracted from the macroalgae S.duplicatum and S.crassifolium found similar to those of the commercially available alginate. Conclusion: Extraction obtained from the macroalgae S.duplicatum and S.crassifolium showed the typical alginate and the morphology, chemical element and functional groups were in agreement with those of the commercially available alginate.Latar belakang: Alginat dari berbagai penjuru dunia telah digunakan untuk kegunaan rekayasa jaringan. Alginat dari alga makro Sargassum yang diperoleh dari Indonesia telah digunakan untuk berbagai kegunaan, namun ini belum diterapkan untuk scaffold jaringan. Tujuan: Untuk mengekstrak alginat dari alga makro

Influence of synthetic surfactants on the uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Masakorala, Kanaji [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)], E-mail: aturner@plymouth.ac.uk; Brown, Murray T. [School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

2008-12-15

Uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca, has been studied in the presence of an anionic (sodium dodecyl sulphate, SDS), cationic (hexadecyltrimethylammonium bromide; HDTMA) and non-ionic (Triton X-100; TX) surfactant. Compared with the surfactant-free system, metal sorption was reduced in the presence of SDS or TX. Neither surfactant, however, had any measurable impact on cell membrane permeability, determined by leakage of dissolved free amino acids (DFAA), or on metal internalisation. We attribute these observations to the stabilisation of aqueous Cd and Pb by SDS and the shielding of otherwise amenable sorption sites by TX. Presence of HDTMA resulted in a reduction in the extent of both sorption and internalisation of all metals and a significant increase in the leakage of DFAA. Thus, by enhancing membrane permeability, HDTMA exerts the greatest influence on metal behaviour in the presence of U. lactuca. - Synthetic surfactants exert a significant impact on the uptake and internalisation of metals by a marine macroalga.

Influence of synthetic surfactants on the uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca

International Nuclear Information System (INIS)

Masakorala, Kanaji; Turner, Andrew; Brown, Murray T.

2008-01-01

Uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca, has been studied in the presence of an anionic (sodium dodecyl sulphate, SDS), cationic (hexadecyltrimethylammonium bromide; HDTMA) and non-ionic (Triton X-100; TX) surfactant. Compared with the surfactant-free system, metal sorption was reduced in the presence of SDS or TX. Neither surfactant, however, had any measurable impact on cell membrane permeability, determined by leakage of dissolved free amino acids (DFAA), or on metal internalisation. We attribute these observations to the stabilisation of aqueous Cd and Pb by SDS and the shielding of otherwise amenable sorption sites by TX. Presence of HDTMA resulted in a reduction in the extent of both sorption and internalisation of all metals and a significant increase in the leakage of DFAA. Thus, by enhancing membrane permeability, HDTMA exerts the greatest influence on metal behaviour in the presence of U. lactuca. - Synthetic surfactants exert a significant impact on the uptake and internalisation of metals by a marine macroalga

Descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham: III. Influencia de la densidad y diversidad de la macrofauna asociada Litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham: III. Influence of density and diversity of the associated macrofauna

Directory of Open Access Journals (Sweden)

Saray Sánchez

2010-03-01

Full Text Available Con el objetivo de determinar la descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala y su relación con la densidad y la diversidad de la macrofauna asociada, se realizó este experimento en la EEPF «Indio Hatuey». Esta se determinó como la pérdida de biomasa a través del tiempo, con relación al peso inicial. Para el estudio de la dinámica de la descomposición se utilizó el método de bolsas de hojarasca (litter bags. Se escogieron al azar cuatro bolsas a los 30, 60, 90, 120, 150, 180 y 210 días de situadas en el pastizal. En cada fecha de recolección, a la hojarasca remanente de cada bolsa se le determinó la población de macrofauna (organismos con diámetro mayor que 2 mm mediante la separación manual, y se calculó el valor promedio de la densidad (individuos/m², así como la abundancia proporcional (% para cada taxón. Se utilizó el análisis de correlación y regresión para conocer la interrelación entre las variables y los modelos de mejor ajuste. De acuerdo con los resultados se concluye que las condiciones de humedad y temperatura que genera el árbol en este sistema, así como la calidad de su hojarasca, posibilitan la presencia de una diversa y estable fauna asociada a las bolsas, la cual influyó en el proceso de descomposición.The trial was conducted at the EEPF «Indio Hatuey» in order to determine the litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala and its relation to the density and diversity of the associated macrofauna. It was determined as biomass loss through time, with regards to initial weight. For the study of the decomposition dynamics the litter bag method was used. Four bags were randomly chosen 30, 60, 90, 120, 150, 180 and 210 days after being placed in the pastureland. In each collection date, to the remnant litter of each bag, the macrofauna (organisms with diameter higher than 2 mm population was

The Hawaiian freshwater algae biodiversity survey (2009–2014): systematic and biogeographic trends with an emphasis on the macroalgae

Science.gov (United States)

2014-01-01

Background A remarkable range of environmental conditions is present in the Hawaiian Islands due to their gradients of elevation, rainfall and island age. Despite being well known as a location for the study of evolutionary processes and island biogeography, little is known about the composition of the non-marine algal flora of the archipelago, its degree of endemism, or affinities with other floras. We conducted a biodiversity survey of the non-marine macroalgae of the six largest main Hawaiian Islands using molecular and microscopic assessment techniques. We aimed to evaluate whether endemism or cosmopolitanism better explain freshwater algal distribution patterns, and provide a baseline data set for monitoring future biodiversity changes in the Hawaiian Islands. Results 1,786 aquatic and terrestrial habitats and 1,407 distinct collections of non-marine macroalgae were collected from the islands of Kauai, Oahu, Molokai, Maui, Lanai and Hawaii from the years 2009–2014. Targeted habitats included streams, wet walls, high elevation bogs, taro fields, ditches and flumes, lakes/reservoirs, cave walls and terrestrial areas. Sites that lacked freshwater macroalgae were typically terrestrial or wet wall habitats that were sampled for diatoms and other microalgae. Approximately 50% of the identifications were of green algae, with lesser proportions of diatoms, red algae, cyanobacteria, xanthophytes and euglenoids. 898 DNA sequences were generated representing eight different markers, which enabled an assessment of the number of taxonomic entities for genera collected as part of the survey. Forty-four well-characterized taxa were assessed for global distribution patterns. This analysis revealed no clear biogeographic affinities of the flora, with 27.3% characterized as “cosmopolitan”, 11.4% “endemic”, and 61.3% as intermediate. Conclusions The Hawaiian freshwater algal biodiversity survey represents the first comprehensive effort to characterize the non

Biological validation of physical coastal waters classification along the NE Atlantic region based on rocky macroalgae distribution

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Ramos, Elvira; Puente, Araceli; Juanes, José Antonio; Neto, João M.; Pedersen, Are; Bartsch, Inka; Scanlan, Clare; Wilkes, Robert; Van den Bergh, Erika; Ar Gall, Erwan; Melo, Ricardo

2014-06-01

A methodology to classify rocky shores along the North East Atlantic (NEA) region was developed. Previously, biotypes and the variability of environmental conditions within these were recognized based on abiotic data. A biological validation was required in order to support the ecological meaning of the physical typologies obtained. A database of intertidal macroalgae species occurring in the coastal area between Norway and the South Iberian Peninsula was generated. Semi-quantitative abundance data of the most representative macroalgal taxa were collected in three levels: common, rare or absent. Ordination and classification multivariate analyses revealed a clear latitudinal gradient in the distribution of macroalgae species resulting in two distinct groups: one northern and one southern group, separated at the coast of Brittany (France). In general, the results based on biological data coincided with the results based on physical characteristics. The ecological meaning of the coastal waters classification at a broad scale shown in this work demonstrates that it can be valuable as a practical tool for conservation and management purposes.

An evaluation of the toxicity and bioaccumulation of cisplatin in the marine environment using the macroalga, Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Easton, Cecilia [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew, E-mail: aturner@plymouth.ac.uk [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Sewell, Graham [School of Health Professions, University of Plymouth, Peninsula Allied Health Centre, Plymouth PL6 8BH (United Kingdom)

2011-12-15

The cytotoxic drug, cisplatin (cis-PtCl{sub 2}(NH{sub 3}){sub 2}), has been added to cultures of the marine macroalga, Ulva lactuca, under various experimental conditions. Both accumulation and internalisation over a 48 h period was greater when cisplatin was added to coastal sea water (salinity = 33) from a distilled water solution than when added to either sea water or estuarine water (salinity = 16.5) from a saline solution. This effect is attributed to the greater abundance of the more reactive monoaqua complex (cis-PtCl(OH{sub 2})(NH{sub 3}){sub 2}{sup +}) in the distilled water solution and kinetic constraints on its conversion back to cis-PtCl{sub 2}(NH{sub 3}){sub 2} in sea water. Despite its mode of action at the cellular level, cisplatin added up to concentrations of 150 nM did not incur a measurable reduction in the efficiency of photochemical energy conversion under any of experimental conditions tested. - Highlights: > This study is the first to examine the biogeochemistry and toxicity of a cytotoxic drug in the marine environment. > Cisplatin is accumulated and internalised by the marine macroalga, Ulva lactuca. > Accumulation is greater when the drug is administered from a distilled water solution than from a saline solution. > Results are consistent with the greater abundance of the more reactive aquated complexes in pure water. > Cisplatin is not phytotoxic to the alga over the concentration range (<150 nM) studied. - The cytotoxic drug, cisplatin, is accumulated and internalised by the marine macroalga, Ulva lactuca, but is not phytotoxic up to concentrations of 150 nM

Biochars derived from wasted marine macro-algae (Saccharina japonica and Sargassum fusiforme) and their potential for heavy metal removal in aqueous solution.

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Poo, Kyung-Min; Son, Eun-Bi; Chang, Jae-Soo; Ren, Xianghao; Choi, Yun-Jung; Chae, Kyu-Jung

2018-01-15

For the purpose of reusing wasted marine macro-algae generated during cultivation, harvesting, processing and selling processes, biochars derived from Saccharina japonica (known as kelp) and Sargassum fusiforme (known as hijikia) were characterized and their removal capacities for Cu, Cd, and Zn in aqueous solution were assessed. Feedstocks, S. japonica, S. fusiforme, and also pinewood sawdust as a control, were pyrolyzed at 250, 400, 500, 600 and 700 °C. In evaluating heavy metal removal capacities, SJB (S. japonica biochar) showed the best performance, with removal efficiencies of more than 98% for the three heavy metals when pyrolyzed at over 400 °C. SFB (S. fusiforme biochar) also showed good potential as an adsorbent, with removal efficiencies for the three heavy metals of more than 86% when pyrolyzed at over 500 °C. On the contrary, the maximum removal efficiencies of PSB (pinewood sawdust biochar) were 81%, 46%, and 47% for Cu, Cd, and Zn, respectively, even at 700 °C, the highest pyrolysis temperature. This demonstrates that marine macro-algae were advantageous in terms of production energy for removing heavy metals even at relatively low pyrolysis temperatures, compared with PSB. The excellent heavy metal adsorption capacities of marine macro-algae biochars were considered due to their higher pH and more oxygen-containing functional groups, although the specific surface areas of SJB and SFB were significantly lower than that of PSB. This research confirmed that the use of marine macro-algae as a heavy metal adsorbent was suitable not only in the removal of heavy metals, but also in terms of resource recycling and energy efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

A multiresidue approach for the simultaneous quantification of antibiotics in macroalgae by ultra-high performance liquid chromatography-tandem mass spectrometry.

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Leston, Sara; Freitas, Andreia; Rosa, João; Barbosa, Jorge; Lemos, Marco F L; Pardal, Miguel Ângelo; Ramos, Fernando

2016-10-15

Together with fish, algae reared in aquaculture systems have gained importance in the last years, for many purposes. Besides their use as biofilters of effluents, macroalgae's rich nutritional profiles have increased their inclusion in human diets but also in animal feeds as sources of fatty acids, especially important for the fish industry. Nonetheless, algae are continuously exposed to environmental contaminants including antibiotics and possess the ability for bioaccumulation of such compounds. Therefore, the present paper describes the development and validation of an ultra-high performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of antibiotics in the green macroalgae Ulva lactuca. This multi-residue method enables the determination of 38 compounds distributed between seven classes and was fully validated according to EU Decision 2002/657/EC. Copyright © 2016 Elsevier B.V. All rights reserved.

Functional composition of epifauna in the south-eastern North Sea in relation to habitat characteristics and fishing effort

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Neumann, Hermann; Diekmann, Rabea; Kröncke, Ingrid

2016-02-01

Analysis of ecosystem functioning is essential to describe the ecological status of ecosystems and is therefore directly requested in international directives. There is a lack of knowledge regarding functional aspects of benthic communities and their environmental and anthropogenic driving forces in the southern North Sea. This study linked functional composition of epibenthic communities to environmental conditions and fishing effort and investigated spatial correlations between habitat characteristics to gain insight into potential synergistic and/or cumulative effects. Functional composition of epifauna was assessed by using biological trait analysis (BTA), which considered 15 ecological traits of 54 species. Functional composition was related to ten predictor variables derived from sediment composition, bottom temperature and salinity, hydrodynamics, annual primary production and fishing effort. Our results revealed significantly different functional composition between the Dogger Bank, the Oyster Ground, the West and North Frisian coast. Mobility, feeding type, size and adult longevity were the most important traits differentiating the communities. A high proportion of trait modalities related to an opportunistic life mode were obvious in coastal areas especially at the West Frisian coast and in the area of the Frisian Front indicating disturbed communities. In contrast, functional composition in the Dogger Bank area indicated undisturbed communities with prevalence of large, long-lived and permanently attached species being sensitive towards disturbance such as fishing. Tidal stress, mud content of sediments, salinity, stratification and fishing effort were found to be the most important habitat characteristics shaping functional composition. Strong correlations were found between variables, especially between those which changed gradually from the coast to offshore areas including fishing effort. Unfavourable extremes of these factors in coastal areas

Deashing macroalgae biomass by pulsed electric field treatment.

Science.gov (United States)

Robin, Arthur; Sack, Martin; Israel, Alvaro; Frey, Wolfgang; Müller, Georg; Golberg, Alexander

2018-05-01

Among all biomass constituents, the ashes are major hurdles for biomass processing. Ashes currently have low market value and can make a non-negligible fraction of the biomass dry weight significantly impacting its further processing by degrading equipment, lowering process yield, inhibiting reactions and decreasing products qualities. However, most of the current treatments for deashing biomass are of poor efficiency or industrial relevance. This work is the first report on the use of Pulsed Electric Field (PEF) to enhance deashing of biomass from a high ash content green marine macroalga, Ulva sp., using hydraulic pressing. By inducing cell permeabilization of the fresh biomass, PEF was able to enhance the ash extraction from 18.4% (non-treated control) to 37.4% of the total ash content in average, significantly enhancing the extraction of five of the major ash elements (K, Mg, Na, P and S) compared to pressing alone. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of filamentous macroalgae on growth and survival of eelgrass, Zostera marina, seedlings

DEFF Research Database (Denmark)

Rasmussen, Jonas; Krause-Jensen, Dorte; Olesen, Birgit

of oxygen and sulphide and their diurnal variations in the mats were measured using microelectrodes. Seedling growth rates declined 99 % from controls to the high C. linum cover treatment and 55 % to the high imitation algae treatment. But due to high water flow rates anoxic conditions failed to develop...... on a 2-factorial laboratory experiment. Eelgrass seedlings were grown with three different heights and two different types of algae mats: Chaetomorpha linum and artificial macroalgae. The two types of mats were used to separate the physical and metabolic effects of algal presence. Concentrations...

Macro-algae biomass and cover from nearshore regions of the Nantorium War Memorial, Waikiki, Oahu, Hawaii, 1966-2005 (NODC Accession 0040082)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Department of Zoology, University of Hawaii at Manoa, incorporated surveys of macro-algae as part of the Zoology 439L "Laboratory in Ecology" during annual field...

Macro-algae Biomass and Cover from Nearshore Regions of the Natatorium War Memorial, Waikiki, Oahu, Hawaii 1966-2005 (NODC Accession 0040082)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Department of Zoology, University of Hawaii at Manoa, incorporated surveys of macro-algae as part of the Zoology 439L "Laboratory in Ecology" during annual field...

Distribution, diversity and bioprospecting of bioactive compounds from cryptic fungal communities associated with endemic and cold-adapted macroalgae in Antarctica

Science.gov (United States)

We surveyed the distribution and diversity of fungi associated with eight macroalgae from Antarctica and their capability to produce bioactive compounds. The collections yielded 148 fungal isolates identified using molecular methods into 21 genera and 43 species. The most frequent taxa were Geomyces...

Non-destructive alpha-particle activation analysis of P, Cl, K and Ca in marine macro-alga samples using synthetic multielement reference material as comparative standard

International Nuclear Information System (INIS)

Iwata, Y.; Naitoh, H.; Suzuki, N.

1992-01-01

A Synthetic Reference Material (SyRM) composed with accurately known amounts of 12 elements has been prepared. The elemental composition of the SyRM is closely similar to that of marine macro-algae sample. The elemental composition of the SyRM was regulated by the starting materials used for the synthesis. The SyRM was used as a comparative standard for non-destructive alpha-particle activation analysis of marine macro-alga samples. P, Cl, K and Ca were determined simultaneously without correction for alpha range due to difference in the elemental composition between the analytical samples and the comparative standard. (author) 19 refs.; 4 tabs

Antioxidative sulphated polygalactans from marine macroalgae as angiotensin-I converting enzyme inhibitors.

Science.gov (United States)

Makkar, Fasina; Chakraborty, Kajal

2017-08-17

Antioxidant and antihypertensive potential of the sulphated polygalactans isolated from the marine macroalgae Kappaphycus alvarezii and Gracilaria opuntia were assessed by utilising different in vitro systems. The galactans isolated from K. alvarezii possessed significantly greater antioxidative properties as determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH IC 90 0.97 mg/mL) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS .+ IC 90 0.72 mg/mL) scavenging activities than those isolated from G. opuntia (DPPH IC 90 1.2 mg/mL and ABTS 0.86 mg/mL). The sulphated polygalactan →4)-4-O-sulphonato-(2-O-methyl)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-(2-O-methyl)-α-D-galactopyranan from K. alvarezii showed greater angiotensin-I-converting enzyme (ACE) inhibitory activity (IC 50 0.02 μg/mL) than →3)-4-O-sulphonato-(6-O-acetyl)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-(2-O-sulphonato)-α-D-galactopyranosyl-(1→3)-4-O-sulphonato-(6-O-acetyl)-β-D-xylosyl-(1→3)-4-O-sulphonato-(6-O-acetyl)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-(2-O-sulphonato)-α-D-galactopyranan motif extracted from G. opuntia (IC 50 0.70 μg/mL). Structure activity correlation studies displayed that the ACE inhibitory properties of titled polygalactans were directly proportional to their electronic properties and inversely with the steric and hydrophobic characteristics. Putative ACE inhibitory mechanism of action of sulphated galactans from marine macroalgae corroborated the structure bioactivity correlation analysis.

Production and characterization of enzymatic cocktail produced by Aspergillus niger using green macroalgae as nitrogen source and its application in the pre-treatment for biogas production from Ulva rigida.

Science.gov (United States)

Karray, Raida; Hamza, Manel; Sayadi, Sami

2016-09-01

Marine macroalgae are gaining more and more importance as a renewable feedstock for durable bioenergy production, but polysaccharides of this macroalgae are structurally complex in its chemical composition. The use of enzymatic hydrolysis may provide new pathways in the conversion of complex polysaccharides to fermentable sugars. In this study, an enzymatic cocktail with high specificity was first isolated from Aspergillus niger using the green macroalgae Ulva rigida as nitrogen source. The cocktail is rich on β-glucosidase, pectinase and carboxy-methyl-cellulase (CMCase). The highest activity was obtained with β-glucosidase (109IUmL(-1)) and pectinase (76IUmL(-1)), while CMCase present the lowest activity 4.6IUmL(-1). The U. rigida pre-treatment with this enzymatic cocktail showed high rate of reduced sugar release, and could bring promising prospects for enzymatic pre-treatment of the biogas production from U. rigida biomass which reached 1175mLgCODint(-1). Copyright © 2016 Elsevier Ltd. All rights reserved.

The plastid genome of the red macroalga Grateloupia taiwanensis (Halymeniaceae.

Directory of Open Access Journals (Sweden)

Michael S DePriest

Full Text Available The complete plastid genome sequence of the red macroalga Grateloupia taiwanensis S.-M.Lin & H.-Y.Liang (Halymeniaceae, Rhodophyta is presented here. Comprising 191,270 bp, the circular DNA contains 233 protein-coding genes and 29 tRNA sequences. In addition, several genes previously unknown to red algal plastids are present in the genome of G. taiwanensis. The plastid genomes from G. taiwanensis and another florideophyte, Gracilaria tenuistipitata var. liui, are very similar in sequence and share significant synteny. In contrast, less synteny is shared between G. taiwanensis and the plastid genome representatives of Bangiophyceae and Cyanidiophyceae. Nevertheless, the gene content of all six red algal plastid genomes here studied is highly conserved, and a large core repertoire of plastid genes can be discerned in Rhodophyta.

The Plastid Genome of the Red Macroalga Grateloupia taiwanensis (Halymeniaceae)

Science.gov (United States)

DePriest, Michael S.; Bhattacharya, Debashish; López-Bautista, Juan M.

2013-01-01

The complete plastid genome sequence of the red macroalga Grateloupia taiwanensis S.-M.Lin & H.-Y.Liang (Halymeniaceae, Rhodophyta) is presented here. Comprising 191,270 bp, the circular DNA contains 233 protein-coding genes and 29 tRNA sequences. In addition, several genes previously unknown to red algal plastids are present in the genome of G. taiwanensis. The plastid genomes from G. taiwanensis and another florideophyte, Gracilaria tenuistipitata var. liui, are very similar in sequence and share significant synteny. In contrast, less synteny is shared between G. taiwanensis and the plastid genome representatives of Bangiophyceae and Cyanidiophyceae. Nevertheless, the gene content of all six red algal plastid genomes here studied is highly conserved, and a large core repertoire of plastid genes can be discerned in Rhodophyta. PMID:23894297

Metabolomic response of a marine bacterium to 3,6-anhydro-l-galactose, the rare sugar from red macroalgae, as the sole carbon source.

Science.gov (United States)

Yun, Eun Ju; Yu, Sora; Kim, Sooah; Kim, Kyoung Heon

2018-03-20

Marine red macroalgae have received much attention as sustainable resources for producing bio-based products. Therefore, understanding the metabolic pathways of carbohydrates from red macroalgae, in fermentative microorganisms, is crucial for efficient bioconversion of the carbohydrates into bio-based products. Recently, the novel catabolic pathway of 3,6-anhydro-l-galactose (AHG), the main component of red macroalgae, was discovered in a marine bacterium, Vibrio sp. strain EJY3. However, the global metabolic network in response to AHG remains unclear. Here, the intracellular metabolites of EJY3 grown on AHG, glucose, or galactose were comparatively profiled using gas chromatography/time-of-flight mass spectrometry. The global metabolite profiling results revealed that the metabolic profile for AHG significantly differed from those for other common sugars. Specifically, the metabolic intermediate of the AHG pathway, 3,6-anhydrogalactonate, was detected during growth only in the presence of AHG; thus, the recently discovered key steps in AHG catabolism was found not to occur in the catabolism of other common sugars. Moreover, the levels of metabolic intermediates related to glycerolipid metabolism and valine biosynthesis were higher with AHG than those with other sugars. These comprehensive metabolomic analytical results for AHG in this marine bacterium can be used as the basis for having fermentative microbial strains to engineered to efficiently utilize AHG from macroalgal biomass. Copyright © 2018 Elsevier B.V. All rights reserved.

[Spectral characteristics variations of chromophoric dissolved organic matter during growth of filamentous green macroalgae].

Science.gov (United States)

Jiang, De-gang; Huang, Qing-hui; Li, Jian-hua

2010-07-01

As an important component of dissolved organic matter (DOM), chromophoric dissolved organic matter (CDOM) plays a central role in the global biogeochemical carbon cycle. Macroalgae are essential producers in aquatic ecosystems. They can release a considerable part of photosynthetic products as CDOM. So changes in optical properties of CDOM are studied on filamentous green macroalgae-Chadophorasle found in tidal flats of a brackish Lake Beihu in natural field condition by using spectrometry. Humic-like fluorescence peaks and protein-like fluorescence peaks detected by fluorescence excitation-emission matrix spectrum (EEMS) change little in control experiment but increase dramatically in incubation experiment. Applying parallel factor analysis (PARAFAC) together with fluorescence excitation-emission matrix can get four components of CDOM (C1, C2, C3 and C4) which are relative to humic-like fluorescence peak A(C), M and protein-like fluorescence peak B, T respectively. In incubation experiment four components increase by 211.5%, 255.8%, 75.3% and 129.3% respectively while in control experiment components have little changes except C1 decreasing by 34.3%. Absorption coefficient alpha (355) increases by 92.9% and has positive significant correlation (P CDOM molecular weight and composition, M and S values in incubation experiment are smaller than in control experiment, which illustrate that aromatic and macromolecular CDOM is produced in growth of Chadophorasle. All results indicate that growth of Chadophorasle can change the content and composition of CDOM.

Retrospective analysis of diversity and species composition of marine macroalgae of Hainan Island (China)

Science.gov (United States)

Titlyanov, Eduard A.; Titlyanova, Tamara V.; Xia, Bangmei; Bartsch, Inka

2016-09-01

Retrospective analysis of diversity and species composition of marine macroalgae of Hainan Island in the period 1933-1992 is presented in this paper. There are two extensive sample collection periods of benthic macroalgae: the early collection (EC) covers a period between the early 1930s and the 1980s before considerable urbanization and reef degradation took place and a late collection (LC) was performed in 1990/1992 during a phase of rapid urbanization. Analysis of data also including an earlier published inventory of green algae covering the same collection sites (Titlyanov et al. 2011a) revealed that the marine flora of the island comprises 426 taxa in total, with 59% red algae, 18% brown algae and 23% green algae. In total 59 species of red algae, 11 species of brown algae and 37 species of green algae sampled during the LC are new records for Hainan Island. Considerable floristic changes between EC and LC became evident. In the LC there were significantly more filamentous, tubular or fine blade-like, and often epiphytic, green and red algae with a high surface-to-volume ratio. Additionally a reduction of green, brown and red algal species with larger fleshy or foliose thalli and a low surface-to-volume ratio was observed. It is assumed that the changes reflect the degradation of the coral reef ecosystem around Hainan, which was damaged by human activities especially in the 1950s-1970s.

Lipid content and fatty acid composition of Mediterranean macro-algae as dynamic factors for biodiesel production

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Dahlia M. El Maghraby

2015-01-01

Full Text Available Using the total lipid contents and fatty acid profiles, the marine macro-algae Jania rubens (Rhodophyceae, Ulva linza (Chlorophyceae and Padina pavonica (Phaeophyceae were evaluated for biodiesel production during the spring, summer and autumn. Seawater parameters such as pH, salinity and temperature were measured. The total lipid content varied from 1.56% (J. rubens to 4.14% (U. linza of dry weight, with the highest values occurring in spring. The fatty acid methyl ester profiles were analysed using gas chromatography. The highest percentage of total fatty acids was recorded in P. pavonica, with 6.2% in autumn, whereas the lowest was in J. rubens, with 68.6% in summer. The relative amount of saturated to unsaturated fatty acids was significantly higher in P. pavonica than in the other macro-algae. Seasonal variations in pH, salinity and temperature had no significant effect on the total lipid and fatty acid contents. Principal component analysis grouped brown and green algae together, whereas red alga grouped out. Furthermore, methyl ester profiles indicate that brown and green seaweeds are preferred, followed by red seaweeds, which appears to have little potential for oil-based products. Therefore, these seaweeds are not targets for biodiesel production.

Impact of seaweed beachings on dynamics of δ15N isotopic signatures in marine macroalgae

International Nuclear Information System (INIS)

Lemesle, Stéphanie; Mussio, Isabelle; Rusig, Anne-Marie; Menet-Nédélec, Florence; Claquin, Pascal

2015-01-01

Highlights: • Two coastal sites (COU, GM) in the Bay of Seine affected by summer seaweed beachings. • The same temporal dynamics of the algal δ 15 N at the two sites. • N and P concentrations in seawater of the two sites dominated by riverine sources. • A coupling between seaweed beachings and N sources of intertidal macroalgae. - Abstract: A fine-scale survey of δ 15 N, δ 13 C, tissue-N in seaweeds was conducted using samples from 17 sampling points at two sites (Grandcamp-Maisy (GM), Courseulles/Mer (COU)) along the French coast of the English Channel in 2012 and 2013. Partial triadic analysis was performed on the parameter data sets and revealed the functioning of three areas: one estuary (EstA) and two rocky areas (GM ∗ , COU ∗ ). In contrast to oceanic and anthropogenic reference points similar temporal dynamics characterized δ 15 N signatures and N contents at GM ∗ and COU ∗ . Nutrient dynamics were similar: the N-concentrations in seawater originated from the River Seine and local coastal rivers while P-concentrations mainly from these local rivers. δ 15 N at GM ∗ were linked to turbidity suggesting inputs of autochthonous organic matter from large-scale summer seaweed beachings made up of a mixture of Rhodophyta, Phaeophyta and Chlorophyta species. This study highlights the coupling between seaweed beachings and nitrogen sources of intertidal macroalgae

Biological Pretreatment of Mexican Caribbean Macroalgae Consortiums Using Bm-2 Strain (Trametes hirsuta and Its Enzymatic Broth to Improve Biomethane Potential

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Raúl Tapia-Tussell

2018-02-01

Full Text Available The macroalgae consortium biomass in the Mexican Caribbean represents an emerging and promising biofuel feedstock. Its biological pretreatment and potential for energetic conversion to biomethane were investigated, since some macroalgae have hard cell walls that present an obstacle to efficient methane production when those substrates are used. It has been revealed by anaerobic digestion assays that pretreatment with a Bm-2 strain (Trametes hirsuta isolated from decaying wood in Yucatan, Mexico was 104 L CH4 kg·VS−1; In fact, the fungal pretreatment produced a 20% increase in methane yield, with important amounts of alkali metals Ca, K, Mg, Na of 78 g/L, ash 35.5% and lignin 15.6%. It is unlikely that high concentrations of ash and alkali metals will produce an ideal feedstock for combustion or pyrolysis, but they can be recommended for a biological process.

IBBEAM- EPIFAUNA

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Biscayne Bay is near the downstream end of the massive Southern and Central Florida Water Management System, which is being modified by the Comprehensive Everglades...

Efecto del fotoperiodo y la razón camarón:macroalga en la remoción de nitrógeno amoniacal total por Gracilaria vermiculophylla, en cultivo con Litopenaeus vannamei, sin recambio de agua

Directory of Open Access Journals (Sweden)

Adolfo Sánchez-Romero

2013-11-01

Full Text Available Se evaluó el efecto del fotoperiodo y la relación de biomasa camarón:macroalga en la remoción de nitrógeno amoniacal total (NAT, por la macroalga Gracilaria vermiculophylla, en cultivo con camarón Litopenaeus vannamei, sin recambio de agua. Se evaluaron cuatro fotoperiodos: 12:12, 14:10, 16:08 y 24:00 h de luz:oscuridad y dos relaciones de biomasa camarón:macroalga, 1:4 y 1:8. El diseño experimental fue factorial de 4x2 con cuatro réplicas por tratamiento. Las menores concentraciones de NAT (0,55 ± 0,17 mg L-1, N-NO² (0,145 ± 0,29 mg L-1 y N-NO3 (3,13 ± 0,73 mg L-1 se registraron en la relación 1:8. Las mayores tasas de crecimiento de la macroalga (3,07 ± 1,44% día-1 se obtuvieron con fotoperiodo de 24:00 h y relación de biomasa 1:8. La mayor tasa de incorporación de N en la macroalga (0,31 ± 0,12 mg N L-1 día-1 ocurrió en las mismas condiciones. El crecimiento del camarón fue similar al reportado en sistemas tradicionales de recirculación. La integración de G. vermiculophylla en el sistema sin recambio, fue capaz de mantener los niveles de compuestos nitrogenados tóxicos en niveles favorables para el crecimiento de L. vannamei.

MAPPING SPATIAL/TEMPORAL DISTRIBUTIONS OF GREEN MACROALGAE IN A PACIFIC NORTHWEST COASTAL ESTUARY VIA SMALL FORMAT COLOR INFRARED AERIAL PHOTOGRAPHY

Science.gov (United States)

A small format 35 mm hand-held camera with color infrared slide film was used to map blooms of benthic green macroalgae upon mudflats of Yaquina Bay estuary on the central Oregon coast, U.S.A. Oblique photographs were taken during a series of low tide events, when the intertidal...

Optimization of renewable pinene production from the conversion of macroalgae Saccharina latissima

Energy Technology Data Exchange (ETDEWEB)

Scullin, Chessa [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States); Stavila, Vitalie [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Skarstad, Anita [Statoil Research Center, Trondheim (Norway); Keasling, Jay D. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Univ. of California, Berkeley, CA (United States); Simmons, Blake A. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States); Singh, Seema [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States)

2015-05-01

The enzymatic hydrolysis of Saccharina latissima with laminarinase was compared to hydrolysis with different combinations of cellulase and hemicellulase enzyme mixtures. The hemicellulase mixture resulted in similar release of glucose, while the cellulase mixture released 40% more glucose than laminarinase alone. The combination of a laminarinase augmented with a cellulase mixture resulted in a 53% increase of glucose release from S. latissima than laminarinase. Increasing biomass loading above 4% (w/v) reduced the sugar yield. Resulting macroalgae hydrolysates were used as a carbon source for the production of pinene, making use of a novel two plasmid Escherichia coli system. The macroalgal hydrolysates were suitable for the novel microbial production of pinene with no further treatment and/or purification.

Biosorption removal of benzene and toluene by three dried macroalgae at different ionic strength and temperatures: Algae biochemical composition and kinetics.

Science.gov (United States)

Flores-Chaparro, Carlos E; Chazaro Ruiz, Luis Felipe; Alfaro de la Torre, Ma Catalina; Huerta-Diaz, Miguel Angel; Rangel-Mendez, Jose Rene

2017-05-15

Release of low-molecular aromatic hydrocarbons (HC) into natural waters brings severe consequences to our environment. Unfortunately very limited information is available regarding the treatment of these pollutants. This work evaluated the use of brown, green and red macroalgae biomass as biosorbents of benzene and toluene, two of the most soluble HC. Raw seaweed biomasses were completely characterized, then evaluated under different temperatures and ionic strengths to assess their potential as biosorbents and to elucidate the biosorption mechanisms involved. Brown macroalgae registered the highest removal capacities for benzene and toluene (112 and 28 mg·g -1 , respectively), and these were not affected at ionic strength < 0.6 M. Langmuir and Sips isotherm equations well described biosorption data, and the pseudo-second order model provided the best fit to the kinetics rate. Hydrocarbons are adsorbed onto the diverse chemical components of the cell wall by London forces and hydrophobic interactions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of sodium bicarbonate concentration on growth, photosynthesis, and carbonic anhydrase activity of macroalgae Gracilariopsis lemaneiformis, Gracilaria vermiculophylla, and Gracilaria chouae (Gracilariales, Rhodophyta).

Science.gov (United States)

Zhou, Wei; Sui, Zhenghong; Wang, Jinguo; Hu, Yiyi; Kang, Kyoung Ho; Hong, Hye Ran; Niaz, Zeeshan; Wei, Huihui; Du, Qingwei; Peng, Chong; Mi, Ping; Que, Zhou

2016-06-01

There is potential for bicarbonate to improve crop yields and economic efficiency of marine algae. However, few studies have focused on the effect of bicarbonate on the growth, photosynthesis, and enzyme activity associated with carbon utilization, especially in commercial macroalgae. Here, the addition of bicarbonate (up to 420 mg L(-1)) to macroalgal cultures has been evaluated for Gracilariopsis lemaneiformis, Gracilaria vermiculophylla, and Gracilaria chouae with respect to growth rate, photosynthetic activity, carbonic anhydrase activity, and biochemical composition. The results showed that the effects of NaHCO3 on growth, chlorophyll a, phycoerythrin, photosynthetic oxygen evolution, photochemical parameters of PSI and PSII, carbonic anhydrase activity, and nitrogen content were significant (P 336 mg L(-1) for Gp. lemaneiformis and >420 mg L(-1) for the other two species). Moreover, species-specific differences induced by supplementation with bicarbonate were discovered during culture. Optimal concentrations of NaHCO3 used in this study were 252 mg L(-1) for Gp. lemaneiformis and 336 mg L(-1) for G. vermiculophylla and G. chouae. These results suggest that an adequate supplementation of sodium bicarbonate is a viable strategy for promoting growth and photosynthetic activity in some macroalgae as well as for improving biochemical composition. The study will help to accelerate the growth rate of algae and improve the quality of thalli, and will also be useful for enhancing the understanding of carbon utilization in macroalgae.

Macroalgae Laminaria digitata and Saccharina latissima as Potential Biomasses for Biogas and Total Phenolics Production: Focusing on Seasonal and Spatial Variations of the Algae

DEFF Research Database (Denmark)

D'Este, Martina; Alvarado-Morales, Merlin; Ciofalo, Anna

2017-01-01

Laminaria digitata (L. digitata) and Saccharina latissima (S. latissima) are the most common species of macroalgae in the north Atlantic and north Pacific. Because of their interesting composition, they have recently attracted attention as useful biomass for various purposes such as for biochemic......Laminaria digitata (L. digitata) and Saccharina latissima (S. latissima) are the most common species of macroalgae in the north Atlantic and north Pacific. Because of their interesting composition, they have recently attracted attention as useful biomass for various purposes...... such as for biochemicals and bioenergy production. Nevertheless their composition varies according to the season and to the local environmental conditions. Therefore, in this study different samples harvested throughout a year and in different locations in Denmark were analyzed. The aim of the study was identifying...

Studies of marine macroalgae: saline desert water cultivation and effects of environmental stress on proximate composition. Final subcontract report. [Gracilaria tikvahiae; Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Ryther, J.H.; DeBusk, T.A.; Peterson, J.E.

1985-11-01

The results presented in this report address the growth potential of marine macroalgae cultivated in desert saline waters, and the effects of certain environmental stresses (e.g., nitrogen, salinity, and temperature) on the proximate composition of several marine macroalgae. Two major desert saline water types were assayed for their ability to support the growth of Gracilaria, Ulva, and Caulerpa. Both water types supported short term growth, but long term growth was not supported. Carbohydrate levels in Gracilaria were increased by cultivation under conditions of high salinity, low temperature, and low nitrogen and phosphorous availability. Data suggests that it may be possible to maximize production of useful proximate constituents by cultivating the algae under optimum conditions for growth, and then holding the resulting biomass under the environmental conditions which favor tissue accumulation of the desired storage products. 16 refs., 21 figs., 19 tabs.

Design of a macroalgae amperometric biosensor; application to the rapid monitoring of organophosphate insecticides in an agroecosystem.

Science.gov (United States)

Nunes, G S; Lins, J A P; Silva, F G S; Araujo, L C; Silva, F E P S; Mendonça, C D; Badea, M; Hayat, A; Marty, J-L

2014-09-01

The immobilization of enzymes onto transducer support is a mature technology and has been successfully implemented to improve biocatalytic processes for diverse applications. However, there exists still need to design more sophisticated and specialized strategies to enhance the functional properties of the biosensors. In this work, a biosensor platform based on innovative fabrication strategy was designed, and employed for the detection of organophosphate (OP) in natural waters. The biosensor was prepared by incorporating acetylcholinesterase enzyme (AChE) to the graphite paste modified with tetracyanoquinodimethane (TCNQ) mediator, along with the use of a macroalgae (Cladaphropsis membranous) as a functional immobilization support. The novel immobilization design resulted in a synergic effect, and led to enhanced stability and sensitivity of the biosensor. The designed biosensor was used to analyze methyl parathion OP insecticide in water samples collected from a demonstrably contaminated lake of São Luis Island, Maranhão, Northeast of Brazil. Water analysis revealed that the aquatic ecosystem was polluted by sub-ppm concentrations of the OP insecticide, and a good correlation was found between values obtained through biosensor and GC-MS techniques. Our results demonstrated that macroalgae-biosensor could be used as a low-cost and sensitive screening method to detect target analyte. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization and consequences of intermittent sediment oxygenation by macrofauna: interpretation of high-resolution data sets

Science.gov (United States)

Meile, C. D.; Dwyer, I.; Zhu, Q.; Polerecky, L.; Volkenborn, N.

2017-12-01

Mineralization of organic matter in marine sediments leads to the depletion of oxygen, while activities of infauna introduce oxygenated seawater to the subsurface. In permeable sediments solutes can be transported from animals and their burrows into the surrounding sediment through advection over several centimeters. The intermittency of pumping leads to a spatially heterogeneous distribution of oxidants, with the temporal dynamics depending on sediment reactivity and activity patterns of the macrofauna. Here, we present results from a series of experiments in which these dynamics are studied at high spatial and temporal resolution using planar optodes. From O2, pH and pCO2 optode data, we quantify rates of O2 consumption and dissolved inorganic carbon production, as well alkalinity dynamics, with millimeter-scale resolution. Simulating intermittent irrigation by imposed pumping patterns in thin aquaria, we derive porewater flow patterns, which together with the production and consumption rates cause the chemical distributions and the establishment of reaction fronts. Our analysis thus establishes a quantitative connection between the locally dynamic redox conditions relevant for biogeochemical transformations and macroscopic observations commonly made with sediment cores.

The role of topographic structure and soil macrofauna presence at spoil heaps during spontaneous succession.

Science.gov (United States)

Walmsley, Alena; Vachová, Pavla; Vach, Marek

2016-04-01

This research was investigating whether topographic features, which determine soil nutrient and moisture distribution, in combination with soil fauna (wireworm and earthworm) presence, affect plant community composition at a spontaneously revegetated post mining area with an undulating surface. Two sites of different age with 3 types of topographic features were selected, soil moisture and nutrient content were measured, plant community composition and soil macrofauna community was sampled at each position. Wireworms were present at all positions and were most abundant at bottoms of waves at the younger site; their presence was correlated with several plant species, but the direction of the interaction isn't clear. Earthworms were only present at the older site and had highest abundance at flat sections. Earthworm presence affected the amount of nitrogen in soil - the most nitrogen content was at the site with highest earthworm density and was followed by higher diversity of plant community. The plant community composition was generally correlated with plant available nutrient content - especially P and N. We infer that topographic features affect nutrient and soil fauna distribution, which consequently influences plant community composition.

Anti-Inflammatory and Antinociceptive Effects of Ethyl Acetate Fraction of an Edible Red Macroalgae Sarcodia ceylanica

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Chieh-Chih Shih

2017-11-01

Full Text Available Research so far has only shown that edible red macroalgae, Sarcodia ceylanica has the ability to eliminate free radicals and anti-diabetic, anti-bacterial properties. This study was conducted both in vitro and in vivo on the ethyl acetate extract (PD1 of farmed red macroalgae in order to explore its anti-inflammatory properties. In order to study the in vitro anti-inflammatory effects of PD1, we used lipopolysaccharide (LPS to induce inflammatory responses in murine macrophages. For evaluating the potential in vivo anti-inflammatory and antinociceptive effects of PD1, we used carrageenan-induced rat paw edema to produce inflammatory pain. The in vitro results indicated that PD1 inhibited the LPS-induced pro-inflammatory protein, inducible nitric oxide synthase (iNOS in macrophages. Oral PD1 can reduce carrageenan-induced paw edema and inflammatory nociception. PD1 can significantly inhibit carrageenan-induced leukocyte infiltration, as well as the protein expression of inflammatory mediators (iNOS, interleukin-1β, and myeloperoxidase in inflammatory tissue. The above results indicated that PD1 has great potential to be turned into a functional food or used in the development of new anti-inflammatory and antinociceptive agents. The results from this study are expected to help scientists in the continued development of Sarcodia ceylanica for other biomedical applications.

CUANTIFICACIÓN DE CARBOHIDRATOS, POLIFENOLES Y SULFATOS EN EXTRACTOS DE MACROALGAS PROMISORIAS PARA LA ACUICULTURA

OpenAIRE

Salas, N.; Lengua, R.; Becerra, E.; Bazán, D.; Santome, S.; Córdova, C.

2015-01-01

En el presente trabajo, se  determinó el contenido de Carbohidratos, polifenoles y  sulfatos en muestras de macroalgas marinas, las que se recolectaron en la  Bahía de Pisco-Ica y  en la  playa de Barranco. Las muestras estudiadas son las siguientes:    Macrocystis Pyrifera, Ulva Nematoidea, Lessonia Trabeculata, Chondracanthus Chamissoi. Se observó que el alga     Chondracanthus Chamissoi  femenina  es la que tiene mayor cantidad de carbohidratos,  el   alga Macrocystis Pyrifera  es la que  ...

Optimization of renewable pinene production from the conversion of macroalgae Saccharina latissima.

Science.gov (United States)

Scullin, Chessa; Stavila, Vitalie; Skarstad, Anita; Keasling, Jay D; Simmons, Blake A; Singh, Seema

2015-05-01

Enzymatic hydrolysis of Saccharina latissima with laminarinase was compared to hydrolysis with different combinations of cellulase and hemicellulase enzyme mixtures. The hemicellulase mixture resulted in similar release of glucose, while the cellulase mixture released 40% more glucose than laminarinase alone. The combination of a laminarinase augmented with a cellulase mixture resulted in a 53% increase of glucose release from S. latissima than laminarinase. Increasing biomass loading above 4% (w/v) reduced the sugar yield. Resulting macroalgae hydrolysates were used as a carbon source for the production of pinene, making use of a novel two plasmid Escherichia coli system. The macroalgal hydrolysates were suitable for the novel microbial production of pinene with no further treatment and/or purification. Copyright © 2015. Published by Elsevier Ltd.

Macroalgae and phytoplankton as indicators of ecological status of Danish coastal waters

DEFF Research Database (Denmark)

Carstensen, Jacob; Krause-Jensen, Dorte; Dahl, Karsten

This report contributes to the development of tools that can be applied to assess the five classes of ecological status of the Water Framework Directive based on the biological quality elements phytoplankton and macroalgae. Nitrogen inputs and concentrations representing reference conditions...... and boundaries between the five ecological status classes were calculated from estimates of nitrogen inputs from Denmark to the Danish straits since 1900 combined with expert judgement of the general environmental conditions of Danish waters during different time periods. From these calculated nitrogen...... concentrations and a macroalgal model ecological status class boundaries were established for six macroalgal indicators in a number of Danish estuaries and coastal areas. Furthermore, site-specific correlations between concentrations of nitrogen and chlorophyll a were used to define reference conditions...

Removing constraints on the biomass production of freshwater macroalgae by manipulating water exchange to manage nutrient flux.

Directory of Open Access Journals (Sweden)

Andrew J Cole

Full Text Available Freshwater macroalgae represent a largely overlooked group of phototrophic organisms that could play an important role within an industrial ecology context in both utilising waste nutrients and water and supplying biomass for animal feeds and renewable chemicals and fuels. This study used water from the intensive aquaculture of freshwater fish (Barramundi to examine how the biomass production rate and protein content of the freshwater macroalga Oedogonium responds to increasing the flux of nutrients and carbon, by either increasing water exchange rates or through the addition of supplementary nitrogen and CO2. Biomass production rates were highest at low flow rates (0.1-1 vol.day-1 using raw pond water. The addition of CO2 to cultures increased biomass production rates by between 2 and 25% with this effect strongest at low water exchange rates. Paradoxically, the addition of nitrogen to cultures decreased productivity, especially at low water exchange rates. The optimal culture of Oedogonium occurred at flow rates of between 0.5-1 vol.day-1, where uptake rates peaked at 1.09 g.m-2.day-1 for nitrogen and 0.13 g.m-2.day-1 for phosphorous. At these flow rates Oedogonium biomass had uptake efficiencies of 75.2% for nitrogen and 22.1% for phosphorous. In this study a nitrogen flux of 1.45 g.m-2.day-1 and a phosphorous flux of 0.6 g.m-2.day-1 was the minimum required to maintain the growth of Oedogonium at 16-17 g DW.m-2.day-1 and a crude protein content of 25%. A simple model of minimum inputs shows that for every gram of dry weight biomass production (g DW.m-2.day-1, Oedogonium requires 0.09 g.m-2.day-1 of nitrogen and 0.04 g.m-2.day-1 of phosphorous to maintain growth without nutrient limitation whilst simultaneously maintaining a high-nutrient uptake rate and efficiency. As such the integrated culture of freshwater macroalgae with aquaculture for the purposes of nutrient recovery is a feasible solution for the bioremediation of wastewater and the

Removing Constraints on the Biomass Production of Freshwater Macroalgae by Manipulating Water Exchange to Manage Nutrient Flux

Science.gov (United States)

Cole, Andrew J.; de Nys, Rocky; Paul, Nicholas A.

2014-01-01

Freshwater macroalgae represent a largely overlooked group of phototrophic organisms that could play an important role within an industrial ecology context in both utilising waste nutrients and water and supplying biomass for animal feeds and renewable chemicals and fuels. This study used water from the intensive aquaculture of freshwater fish (Barramundi) to examine how the biomass production rate and protein content of the freshwater macroalga Oedogonium responds to increasing the flux of nutrients and carbon, by either increasing water exchange rates or through the addition of supplementary nitrogen and CO2. Biomass production rates were highest at low flow rates (0.1–1 vol.day−1) using raw pond water. The addition of CO2 to cultures increased biomass production rates by between 2 and 25% with this effect strongest at low water exchange rates. Paradoxically, the addition of nitrogen to cultures decreased productivity, especially at low water exchange rates. The optimal culture of Oedogonium occurred at flow rates of between 0.5–1 vol.day−1, where uptake rates peaked at 1.09 g.m−2.day−1 for nitrogen and 0.13 g.m−2.day−1 for phosphorous. At these flow rates Oedogonium biomass had uptake efficiencies of 75.2% for nitrogen and 22.1% for phosphorous. In this study a nitrogen flux of 1.45 g.m−2.day−1 and a phosphorous flux of 0.6 g.m−2.day−1 was the minimum required to maintain the growth of Oedogonium at 16–17 g DW.m−2.day−1 and a crude protein content of 25%. A simple model of minimum inputs shows that for every gram of dry weight biomass production (g DW.m−2.day−1), Oedogonium requires 0.09 g.m−2.day−1 of nitrogen and 0.04 g.m−2.day−1 of phosphorous to maintain growth without nutrient limitation whilst simultaneously maintaining a high-nutrient uptake rate and efficiency. As such the integrated culture of freshwater macroalgae with aquaculture for the purposes of nutrient recovery is a feasible solution for the

New application of two Antarctic macroalgae Palmaria decipiens and Desmarestia menziesii in the synthesis of gold and silver nanoparticles

Science.gov (United States)

González-Ballesteros, N.; González-Rodríguez, J. B.; Rodríguez-Argüelles, M. C.; Lastra, M.

2018-03-01

In this study, two Antarctic macroalgae (Rhodophyta Palmaria decipiens and Phaeophyta Desmarestia menziessi) were selected in order to report their use for the biosynthesis of nanomaterials. Two aqueous extracts of the macroalgae were prepared and their reducing activity, total phenolic content and DPPH scavenging activity were determined, showing that brown seaweed has higher antioxidant activity than red seaweed. Aqueous extracts were used as an eco-friendly, one-pot synthetic route to obtain gold and silver nanoparticles acting both as reducing and stabilizing agents. The nanoparticles obtained were characterized by UV-Vis spectroscopy and Transmission electron microscopy (TEM), demonstrating the formation of gold and silver nanoparticles with mean diameters of 36.8 ± 5.3 and 11.5 ± 3.3 nm for Au@PD and Au@DM and 7.0 ± 1.2 nm and 17.8 ± 2.6 nm in the case of Ag@PD and Ag@DM. Lastly, functional groups of the biomolecules present in the extracts were characterized by Fourier transform infrared spectra (FTIR) prior to, and after, the synthesis of the nanoparticles, in order to obtain information about the biomolecules involved in the reducing and stabilization process.

Techno-Economic Analysis of Biofuel Production from Macroalgae (Seaweed

Directory of Open Access Journals (Sweden)

Mohsen Soleymani

2017-11-01

Full Text Available A techno-economic evaluation of bioenergy production from macroalgae was carried out in this study. Six different scenarios were examined for the production of different energy products and by-products. Seaweed was produced either via the longline method or the grid method. Final products of these scenarios were either ethanol from fermentation, or electricity from anaerobic digestion (AD. By-products were digestate for AD, and animal feed, or electricity and digestate, for the fermentation pathway. Bioenergy breakeven selling prices were investigated according to the cost components and the feedstock supply chain, while suggestions for potential optimization of costs were provided. The lowest production level of dry seaweed to meet 0.93 ($/L for ethanol fuel and 0.07 $/kW-h for electricity was found to be 0.68 and 3.7 million tonnes (dry basis, respectively. At the moment, biofuel production from seaweed has been determined not to be economically feasible, but achieving economic production may be possible by lowering production costs and increasing the area under cultivation.

Techno-Economic Analysis of Biofuel Production from Macroalgae (Seaweed).

Science.gov (United States)

Soleymani, Mohsen; Rosentrater, Kurt A

2017-11-26

A techno-economic evaluation of bioenergy production from macroalgae was carried out in this study. Six different scenarios were examined for the production of different energy products and by-products. Seaweed was produced either via the longline method or the grid method. Final products of these scenarios were either ethanol from fermentation, or electricity from anaerobic digestion (AD). By-products were digestate for AD, and animal feed, or electricity and digestate, for the fermentation pathway. Bioenergy breakeven selling prices were investigated according to the cost components and the feedstock supply chain, while suggestions for potential optimization of costs were provided. The lowest production level of dry seaweed to meet 0.93 ($/L) for ethanol fuel and 0.07 $/kW-h for electricity was found to be 0.68 and 3.7 million tonnes (dry basis), respectively. At the moment, biofuel production from seaweed has been determined not to be economically feasible, but achieving economic production may be possible by lowering production costs and increasing the area under cultivation.

Removal of eutrophication factors and heavy metal from a closed cultivation system using the macroalgae, Gracilaria sp. (Rhodophyta)

Science.gov (United States)

Kang, Kyoung Ho; Sui, Zhenghong

2010-11-01

In this study, the ability of macroalgae Gracilaria sp. of removing eutrophication factors and toxic heavy metals Al, Cr, and Zn in a closed cultivation system is reported. The results show that the concentration of the three heavy metals decreased significantly during the experimental period in an algal biomass dependent manner. The biofiltration capacity of the alga for Al, Cr, and Zn is 10.1%-72.6%, 52.5%-83.4% and 36.5%-91.7%, respectively. Using more materials resulted in stronger heavy metal removal. Additionally, the concentration of chl- a, TN, TP and DIN of water samples from aquariums involving large, medium, and small algal biomass cultivation increased first and then decreased during the experiment. COD value of all three groups decreased with time and displayed algal biomass dependency: more algae resulting in a greater COD value than those of less biomass. Furthermore, changes in COD reflect an obvious organic particles deprivation process of algae. This is the first report on heavy metal removal effect by Gracilaria species. The results suggest that macroalgae can be used as a biofilter for the treatment of nutrient-enriched or heavy-metal polluted water, to which an appropriate time range should be carefully determined.

Indicadores bióticos y fracción de tamaños en la definición de la macrofauna

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Loreto Pino

2015-05-01

Full Text Available El tamaño de la abertura de malla en tamices para retener macrofauna bentónica, podría afectar la estimación de los indicadores bióticos que describen el estado del sistema béntico submareal. El objetivo de este estudio fue determinar el efecto que tendría el límite inferior de abertura de la malla en las estimaciones de indicadores bióticos en dos centros de cultivo de mitílidos en el Seno de Reloncaví, Puerto Montt, Chile. Los datos fueron colectados desde muestras de sedimento obtenidas en estaciones ubicadas dentro y fuera (referencia de los centros de cultivo. Se identificó y cuantificó la macrofauna bentónica con mallas de ≥500 μm y ≥1 mm. Se estimó el índice biótico marino (AMBI, la diversidad de Shannon-Wiener (log2 y riqueza de especies. Los resultados de ambos tamices se compararon mediante prueba t. La especie más abundante en ambas localidades fue el poliqueto Chaetozone setosa, asignado al grupo ecológico GE IV, y la Clase Ostracoda, asignada según expertos chilenos al grupo ecológico GE II. Sólo se observó diferencias significativas en la riqueza de especies en las estaciones dentro del cultivo en el Centro 2. La caracterización de los sitios muestreados en términos de indicadores bióticos permitió identificar que el estado ecológico del bentos de los centros de cultivo se encuentra dentro de los rangos aceptables según límites establecidos para diversidad y AMBI. El uso de la malla de 500 μm aumentó la abundancia de especies oportunistas respecto de lo observado con malla de 1 mm pero no cambió significativamente la clasificación del estado ecológico.

Iron Deficiency in Seagrasses and Macroalgae in the Red Sea Is Unrelated to Latitude and Physiological Performance

KAUST Repository

Anton, Andrea; Hendriks, Iris E.; Marbà , Nú ria; Krause-Jensen, Dorte; Garcias Bonet, Neus; Duarte, Carlos M.

2018-01-01

Iron can limit primary production in shallow marine systems, especially in tropical waters characterized by carbonated sediments, where iron is largely trapped in a non-available form. The Red Sea, an oligotrophic ecosystem characterized by a strong N-S latitudinal nutrient gradient, is a suitable setting to explore patterns in situ of iron limitation in macrophytes and their physiological performance under different iron regimes. We assessed the interactions between environmental gradients and physiological parameters of poorly-studied Red Sea macrophytes. Iron concentration, chlorophyll a concentration, blade thickness, and productivity of 17 species of macrophytes, including seven species of seagrasses and 10 species of macroalgae, were measured at 21 locations, spanning 10 latitude degrees, along the Saudi Arabian coast. Almost 90% of macrophyte species had iron concentrations below the levels indicative of iron sufficiency and more than 40% had critically low iron concentrations, suggesting that iron is a limiting factor of primary production throughout the Red Sea. We did not identify relationships between tissue iron concentration, chlorophyll a concentration and physiological performance of the 17 species of seagrass and macroalgae. There was also no latitudinal pattern in any of the parameters studied, indicating that the South to North oligotrophication of the Red Sea is not reflected in iron concentration, chlorophyll a concentration or productivity of Red Sea macrophytes.

Iron Deficiency in Seagrasses and Macroalgae in the Red Sea Is Unrelated to Latitude and Physiological Performance

KAUST Repository

Anton, Andrea

2018-03-06

Iron can limit primary production in shallow marine systems, especially in tropical waters characterized by carbonated sediments, where iron is largely trapped in a non-available form. The Red Sea, an oligotrophic ecosystem characterized by a strong N-S latitudinal nutrient gradient, is a suitable setting to explore patterns in situ of iron limitation in macrophytes and their physiological performance under different iron regimes. We assessed the interactions between environmental gradients and physiological parameters of poorly-studied Red Sea macrophytes. Iron concentration, chlorophyll a concentration, blade thickness, and productivity of 17 species of macrophytes, including seven species of seagrasses and 10 species of macroalgae, were measured at 21 locations, spanning 10 latitude degrees, along the Saudi Arabian coast. Almost 90% of macrophyte species had iron concentrations below the levels indicative of iron sufficiency and more than 40% had critically low iron concentrations, suggesting that iron is a limiting factor of primary production throughout the Red Sea. We did not identify relationships between tissue iron concentration, chlorophyll a concentration and physiological performance of the 17 species of seagrass and macroalgae. There was also no latitudinal pattern in any of the parameters studied, indicating that the South to North oligotrophication of the Red Sea is not reflected in iron concentration, chlorophyll a concentration or productivity of Red Sea macrophytes.

The Japanese alga Polysiphonia morrowii (Rhodomelaceae, Rhodophyta) on the South Atlantic Ocean: first report of an invasive macroalga inhabiting oyster reefs

Science.gov (United States)

Croce, M. Emilia; Parodi, Elisa R.

2014-06-01

Conspicuous tufts of the filamentous algae Polysiphonia Greville inhabit the reefs of Crassostrea gigas on the Atlantic Patagonian coast. The population was recorded for the first time in 1994 and identified as P. argentinica. This study exhaustively investigated the morphology and reproduction of specimens and the seasonality of the population. The results revealed the identity of the specimens as the invasive Japanese macroalga Polysiphonia morrowii Harvey, on the basis of several striking features: the setaceous and tufted thalli, the corymbose growing apices, the endogenous axillary branches, the urceolate cystocarps and the sharply pointed branches. Sexual reproduction was evidenced; however, fertile male gametophytes were absent in the samples. The population was found almost all year round, but its abundance became higher in autumn and winter. The present study constitutes the first record of this invasive macroalga on the South Atlantic Ocean; the fourth record of an exotic macroalgal species on the Atlantic Patagonian coast; and the first record of an invasive species related to the establishment of C. gigas in Atlantic Patagonia.

Marine macroalgae in the agronomy and potential use of floating sargassum for manure production in the San Andres and Providencia Archipelago, Colombia

International Nuclear Information System (INIS)

Bula Meyer, German

2004-01-01

An account is made on the use of marine macroalgae in agronomy and the potential that floating Sargassum arriving to san Andres and Providencia has for this activity. This Sargassum, which has been a nuisance for the tourist economy of the islands, promises to be an excellent resource for manure production

Spatiotemporal distribution of the benthic macrofauna in an urbanized subtropical estuary: environmental variations and anthropogenic impacts

Directory of Open Access Journals (Sweden)

Pedro Rocha Mattos

Full Text Available Abstract This study was conducted in the Itajaí-Açu river lower estuary in Southern Brazil, in which we aimed to: (1 analyze spatiotemporal variations on the macrofauna; (2 search for relationships between environmental variables and the assembly and (3 evaluate the influence of capital dredging upon the assembly. Two hundred twenty eight samples were performed in four stations, two of which affected by dredging. Sediment (sand, silt and clay, organic matter and carbonate and water column´s variables (temperature, salinity, pH, dissolved oxygen, and turbidity were also assessed. We applied Principal Component Analysis for environmental variables and Hierarchical Clustering for biotic data. Correlations between environmental and biotic matrices were tested by Canonical Analysis of Principal Coordinates. Spatiotemporal variations in the assembly were tested by Permutational Multivariate Analysis of Variance. From the 21.839 organisms sampled, 97% was represented by the gastropod Heleobia australis. Despite the influence of the river discharge on the ecosystem, dredging was deleterious to the assembly, favoring opportunistic organisms such as H. australis.

Diversity and distribution Patterns of the infralittoral green macroalgae from Potiguar basin, Rio Grande do Norte, Northeastern Brazil

OpenAIRE

Cocentino,Adilma de Lourdes Montenegro; Fujii,Mutue Toyota; Reis,Thiago Nogueira de Vasconcelos; Guimarães-Barros,Nathalia Cristina; Rocha,Marcia de França; Neumann-Leitão,Sigrid

2010-01-01

Diversity and distribution pattern of the infralittoral green macroalgae at Potiguar basin, Rio Grande do Norte, Northeastern Brazil were analyzed from material collected at depths varying from 2 to 100 m. Collections were carried out with two types of dredges during four campaigns: July 2002, May and November 2003 and May 2004 at 43 stations. Chlorophyta is represented by 54 species, five varieties and three forms. The most representative family is Caulerpaceae, and the most diverse genus is...

Tropical Atlantic marine macroalgae with bioactivity against virulent and antibiotic resistant Vibrio

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Giselle Cristina Silva

2013-03-01

Full Text Available The antibacterial activity of ethanol, methanol, hexane and acetone-based extracts of the macroalgae Padina gymnospora (PG, Hypnea musciformes (HM, Ulva fasciata (UF and Caulerpa prolifera (CP was investigated. The disk diffusion method was used to evaluate the algae antimicrobial effect against standard strains of Vibrio parahaemolyticus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella enterica and five virulent antibiotic-resistant strains of V. brasiliensis, V. xuii and V. navarrensis (isolated from the hemolymph of Litopenaeus vannamei. Ethanol extracts of PG and HM inhibited all Vibrio strains. E. coli and P. aeruginosa were only susceptible to ethanol extracts of PG. Among the methanol extracts, only UF was bioactive, inhibiting V. navarrensis. The observed inhibitory effect of ethanol extracts of PG, HM and UF against virulent antibiotic-resistant bacteria suggests these macroalgal species constitute a potential source of bioactive compounds.

Effects of urbanisation on macroalgae and sessile invertebrates in southeast Australian estuaries

Science.gov (United States)

Fowles, Amelia E.; Stuart-Smith, Rick D.; Stuart-Smith, Jemina F.; Hill, Nicole A.; Kirkpatrick, Jamie B.; Edgar, Graham J.

2018-05-01

The influence of anthropogenic and environmental factors on the composition, cover and dominance of macroalgae and sessile invertebrates was assessed in three capital city estuaries in south-eastern Australia. Heavy metals and proximity to ports showed the strongest relationships to the distribution of sessile reef biota after accounting for natural environmental gradients. The densities of laminarian, fucoid, brown and red foliose algae were negatively correlated with heavy metals, both in Port Phillip Bay (Melbourne) and the Derwent (Hobart), while turf, filamentous algae and some invertebrates were favoured. Sydney Harbour possessed a different pattern, with the laminarian kelp Ecklonia radiata most abundant near the main shipping port, probably because of biotic interactions involving urchin grazing in the lower estuary. Identifying drivers of benthic community pattern represents a key challenge for effective conservation management, particularly for estuaries affected by multiple anthropogenic impacts.

Ocean Acidification Accelerates the Growth of Two Bloom-Forming Macroalgae.

Science.gov (United States)

Young, Craig S; Gobler, Christopher J

2016-01-01

While there is growing interest in understanding how marine life will respond to future ocean acidification, many coastal ecosystems currently experience intense acidification in response to upwelling, eutrophication, or riverine discharge. Such acidification can be inhibitory to calcifying animals, but less is known regarding how non-calcifying macroalgae may respond to elevated CO2. Here, we report on experiments performed during summer through fall with North Atlantic populations of Gracilaria and Ulva that were grown in situ within a mesotrophic estuary (Shinnecock Bay, NY, USA) or exposed to normal and elevated, but environmentally realistic, levels of pCO2 and/or nutrients (nitrogen and phosphorus). In nearly all experiments, the growth rates of Gracilaria were significantly increased by an average of 70% beyond in situ and control conditions when exposed to elevated levels of pCO2 (p0.05). The δ13C content of both Gracilaria and Ulva decreased two-to-three fold when grown under elevated pCO2 (pacidification, a process that will intensify in the coming decades.

Allelopathic inhibition of photosynthesis in the red tide-causing marine alga, Scrippsiella trochoidea (Pyrrophyta), by the dried macroalga, Gracilaria lemaneiformis (Rhodophyta)

Science.gov (United States)

Ye, Changpeng; Liao, Heping; Yang, Yufeng

2014-07-01

The red tide-causing microalga, Scrippsiella trochoidea was co-cultured with different quantities of dried macroalga Gracilaria lemaneiformis under laboratory conditions, to characterize the allelopathic inhibition effect of the seaweed on photosynthesis of the microalga. Photosynthetic oxygen evolution was measured, and chlorophyll a (Chl a) fluorescence transient O-J-I-P (O, J, I and P point in primary photochemistry reaction curve in photosystem II) curves associated with its specific parameters were determined. A concentration-dependent inhibition of S. trochoidea was observed when the dried seaweed was added. The rate of light-saturated maximum photosynthetic oxygen evolution (Pmax) was markedly decreased, and the O-J-I-P curve coupled with its specific parameters was reduced. The inhibitory effects of the macroalga on the microalga, according to the JIP-test (the relative fluorescence analysis based on O-J-I-P curve) and the activity of oxygen evolution, include a decrease in the number of active reaction centers, the blocking-up of the electron transport chain, and the damage to the oxygen-evolving complex. This study suggests that dried G. lemaneiformis is effective in inhibiting photosynthesis of S. trochoidea, and could thus be a potential candidate for mitigating S. trochoidea blooms.

Occurrence of arsenic in selected marine macroalgae from two coastal areas of South Australia. [Rhodophyceae; phaeophyceae; Chlorophyceae

Energy Technology Data Exchange (ETDEWEB)

Maher, W.A.; Clarke, S.M.

1984-03-01

Total arsenic concentrations have been measured in macroalgae specimens from two coastal areas of South Australia. Phaeophyta in both areas were found to contain elevated arsenic concentrations (42.2-179 ..mu..g g/sup -1/ and 26.3-65.3 ..mu..g g/sup -1/) relative to Rhodophyta (17.6-31.3 ..mu..g g/sup -1/ and 12.5-16.2 ..mu..g g/sup -1/) and Chlorophyta (6.3-16.3 ..mu..g g/sup -1/ and 9.9-10.8 ..mu..g g/sup -1/). 13 references, 3 tables.

An integrated approach to the assessment of the eastern Gulf of Finland health: A case study of coastal habitats

Science.gov (United States)

Berezina, Nadezhda A.; Gubelit, Yulia I.; Polyak, Yulia M.; Sharov, Andrey N.; Kudryavtseva, Valentina A.; Lubimtsev, Vasily A.; Petukhov, Vasily A.; Shigaeva, Tatyana D.

2017-07-01

Eutrophication and chemical pollution are typical threats to the ecosystem of the Gulf of Finland. This paper aims to make a comprehensive assessment of the environmental status of coastal habitats in the easternmost Gulf of Finland (Neva River estuary) by using different physical, chemical and biotic variables to find cost-effective indicators for further monitoring. During summers of 2014 and 2015 we measured water salinity, phosphorus (eutrophication marker), biomass of harmful filamentous macroalgae (coastline hypoxia inductor), sediment hazardous substances (trace metals, polycyclic aromatic hydrocarbons) and other concomitant characters at 12 sites in the gulf. Also, we analyzed responses of the phytoplankton and benthic organisms, including metal-tolerant and hydrocarbon-oxidizing bacteria, meio- and macrofauna, to these factors. We compared the indicative sensitivity and efficiency of several well-known biotic indices and methods, including a Saprobity system (basing on phytoplankton), Raffaelli and Mason index (meiobenthos), and two macrobenthic derived indices (Goodnight-Whitley Index and Benthic Quality Index). Also, we applied a new index - the embryo malformation frequency in benthic amphipods. To estimate the level of bottom hypoxia induced by the macroalgae blooms, we measured the algal cover and thickness of the algal mats. To verify our assessment, we tested correlations between all used variables. Biotic communities of these areas are subjected to high phosphorus and macroalgae blooms, toxic pollution, water salinity and other factors. We concluded that environmental state of coastal habitats at several southern sites (in Koporskaya Bay and near the developing port Bronka) and near port Primorsk in the north was bad, while the state of the rest of sites was moderate or good. The integrated approach for the assessment may be recommended for monitoring programs as an important tool for studying human-mediated and other effects on brackishwater

The potential of acidophilic macroalgae as part of passive bioremediation technology for acid mine drainage in constructed wetlands

CSIR Research Space (South Africa)

Cheng, Po-Hsun

2012-10-01

Full Text Available macroalgae as part of passive bioremediation technology for acid mine drainage in constructed wetlands PH CHENG1,3, PJ OBERHOLSTER1,2, A-M BOTHA3 1CSIR Natural Resources and the Environment, PO Box 320, Stellenbosch, 7599, South Africa 2Department... of diverse benthic algal species to AMD provides the option to utilise them in AMD remediation as part of passive bioremediation technology in constructed wetlands. The purpose of the study was to investigate the bioaccumulation of metals and trace metal...

Testing for the induction of anti-herbivory defences in four Portuguese macroalgae by direct and water-borne cues of grazing amphipods

OpenAIRE

Yun, H. Y.; Cruz, J.; Treitschke, M.; Wahl, Martin; Molis, M.

2007-01-01

Herbivory is a key factor in regulating plant biomass, thereby driving ecosystem performance. Algae have developed multiple adaptations to cope with grazers, including morphological and chemical defences. In a series of experiments we investigated whether several species of macroalgae possess anti-herbivore defences and whether these could be regulated to demand, i.e. grazing events. The potential of direct grazing on defence induction was assessed for two brown (Dictyopteris membranacea, Fuc...

Cyanobacteria and macroalgae in ecosystem of the Neva estuary

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Nikulina V. N.

2011-07-01

Full Text Available The Baltic Sea and Neva estuary are plagued by coastal eutrophication. In order to estimate the scale of the problem, quantitative estimates of phytoplankton and macroalgal mats were determined in the Neva estuary. Long-term monitoring (1982–2009 of phytoplankton showed changes in its species composition and abundance. Summer phytoplankton biomass increased significantly in the 1990s, with concomitant changes in species composition, despite a decline of nutrients in the Neva estuary. The cyanobacteria Planktothrix agardhii became a dominant species. The summer biomass of phytoplankton reached a maximum of 5.2 ± 0.4 mg·L-1 in 2002–2004. Monitoring of macroalgal community in the coastal area of the Neva estuary from 2002 to 2009 showed the dominance of the filamentous green alga Cladophora glomerata in the phytobenthos. Average biomass of macroalgae in inner and outer estuary differed significantly at 132 ± 29 and 310 ± 67 g DW·m-2, respectively. This study showed, that fluctuations in macroalgal biomass reflected human influence on estuary, although it was less sensitive to human impact than the phytoplankton community. Thus qualitative and quantitative characteristics of phytoplankton and macroalgal blooms can indicate anthropogenic influence on the ecosystem, and help to better manage the Neva estuary.

Potential adsorption of methylene blue from aqueous solution using green macroalgaePosidonia oceanica.

Science.gov (United States)

Allouche, F.-N.; Yassaa, N.

2018-03-01

The use of inexpensive biological materials, such as marine algae for removing dyes from contaminated industrial effluents appears as a potential alternative method. The aim of this study is to investigate the aptitude of marine macroalgae Posidonia Oceanica local biomass abundant on the coasts of Algeria for selective sorption of methylene blue (MB) from an aqueous solution in batch experiments at 20 °C. A maximum percentage removal of Posidonia oceanica occurs at pH 5. Equilibrium isotherm data were analyzed using the Langmuir and the Freundlich isotherms. The adsorption equilibrium of methylene blue was best describe by Langmuir model than the Freundlich model. The maximum sorption capacity was 357 mgg-1at pH 5. The sorption data were very well described by the pseudo-second-order model. Keywords: Posidonia oceanica, Methylene blue (MB), Biosorption, Isotherm Equilibrium, Kinetics; Modelling.

Isolation and characterization of marine bacteria from macroalgae Gracilaria salicornia and Gelidium latifolium on agarolitic activity for bioethanol production

Science.gov (United States)

Kawaroe, M.; Pratiwi, I.; Sunudin, A.

2017-05-01

Gracilaria salicornia and Gelidium latifolium have high content of agar and potential to be use as raw material for bioethanol. In bioethanol production, one of the processes level is enzyme hydrolysis. Various microorganisms, one of which is bacteria, can carry out the enzyme hydrolysis. Bacteria that degrade the cell walls of macroalgae and produce an agarase enzyme called agarolytic bacteria. The purpose of this study was to isolate bacteria from macroalgae G. salicornia and G. latifolium, which has the highest agarase enzyme activities, and to obtain agarase enzyme characteristic for bioethanol production. There are two isolates bacteria resulted from G. salicornia that are N1 and N3 and there are two isolates from G. latifolium that are BSUC2 and BSUC4. The result of agarase enzyme qualitative test showed that isolates bacteria from G. latifolium were greater than G. salicornia. The highest agarolitic index of bacteria from G. salicornia produced by isolate N3 was 2.32 mm and isolate N3 was 2.27 mm. Bacteria from G. latifolium produced by isolate BSUC4 was 4.28 mm and isolate BSUC2 was 4.18 mm, respectively. Agarase enzyme activities from isolates N1 and N3 were optimum working at pH 7 and temperature 30 °C, while from isolates BSUC4 was optimum at pH 7 and temperature 50 °C. This is indicated that the four bacteria are appropriate to hydrolyze macro alga for bioethanol production.

Chemical and physical environmental conditions underneath mat- and canopy-forming macroalgae, and their effects on understorey corals.

Science.gov (United States)

Hauri, Claudine; Fabricius, Katharina E; Schaffelke, Britta; Humphrey, Craig

2010-09-13

Disturbed coral reefs are often dominated by dense mat- or canopy-forming assemblages of macroalgae. This study investigated how such dense macroalgal assemblages change the chemical and physical microenvironment for understorey corals, and how the altered environmental conditions affect the physiological performance of corals. Field measurements were conducted on macroalgal-dominated inshore reefs in the Great Barrier Reef in quadrats with macroalgal biomass ranging from 235 to 1029 g DW m(-2) dry weight. Underneath mat-forming assemblages, the mean concentration of dissolved oxygen was reduced by 26% and irradiance by 96% compared with conditions above the mat, while concentrations of dissolved organic carbon and soluble reactive phosphorous increased by 26% and 267%, respectively. The difference was significant but less pronounced under canopy-forming assemblages. Dissolved oxygen declined and dissolved inorganic carbon and alkalinity increased with increasing algal biomass underneath mat-forming but not under canopy-forming assemblages. The responses of corals to conditions similar to those found underneath algal assemblages were investigated in an aquarium experiment. Coral nubbins of the species Acropora millepora showed reduced photosynthetic yields and increased RNA/DNA ratios when exposed to conditions simulating those underneath assemblages (pre-incubating seawater with macroalgae, and shading). The magnitude of these stress responses increased with increasing proportion of pre-incubated algal water. Our study shows that mat-forming and, to a lesser extent, canopy-forming macroalgal assemblages alter the physical and chemical microenvironment sufficiently to directly and detrimentally affect the metabolism of corals, potentially impeding reef recovery from algal to coral-dominated states after disturbance. Macroalgal dominance on coral reefs therefore simultaneously represents a consequence and cause of coral reef degradation.

Chemical and physical environmental conditions underneath mat- and canopy-forming macroalgae, and their effects on understorey corals.

Directory of Open Access Journals (Sweden)

Claudine Hauri

2010-09-01

Full Text Available Disturbed coral reefs are often dominated by dense mat- or canopy-forming assemblages of macroalgae. This study investigated how such dense macroalgal assemblages change the chemical and physical microenvironment for understorey corals, and how the altered environmental conditions affect the physiological performance of corals. Field measurements were conducted on macroalgal-dominated inshore reefs in the Great Barrier Reef in quadrats with macroalgal biomass ranging from 235 to 1029 g DW m(-2 dry weight. Underneath mat-forming assemblages, the mean concentration of dissolved oxygen was reduced by 26% and irradiance by 96% compared with conditions above the mat, while concentrations of dissolved organic carbon and soluble reactive phosphorous increased by 26% and 267%, respectively. The difference was significant but less pronounced under canopy-forming assemblages. Dissolved oxygen declined and dissolved inorganic carbon and alkalinity increased with increasing algal biomass underneath mat-forming but not under canopy-forming assemblages. The responses of corals to conditions similar to those found underneath algal assemblages were investigated in an aquarium experiment. Coral nubbins of the species Acropora millepora showed reduced photosynthetic yields and increased RNA/DNA ratios when exposed to conditions simulating those underneath assemblages (pre-incubating seawater with macroalgae, and shading. The magnitude of these stress responses increased with increasing proportion of pre-incubated algal water. Our study shows that mat-forming and, to a lesser extent, canopy-forming macroalgal assemblages alter the physical and chemical microenvironment sufficiently to directly and detrimentally affect the metabolism of corals, potentially impeding reef recovery from algal to coral-dominated states after disturbance. Macroalgal dominance on coral reefs therefore simultaneously represents a consequence and cause of coral reef degradation.

Microsensor Studies of Oxygen and Light-Distribution in the Green Macroalga Codium Fragile

DEFF Research Database (Denmark)

LASSEN, C.; BEBOUT, LE; PAERL, HW

1994-01-01

to multiple scattering in the medullary tissue. The constant intensity of visible light below 0.2 mm was thus a result of the combined effects of absorption and backscattering from the medulla. The oxygen exchange between the alga and the surrounding water was diffusion-limited with a steep O-2 gradient......Scalar irradiance, oxygen concentration, and oxygenic photosynthesis were measured at 0.1 mm spatial resolution within the tissue of the siphonous green macroalga Codium fragile subsp. tomentosoides (van Goer) Silva by fiber-optic scalar irradiance microsensors and oxygen microelectrodes......, The scalar irradiance of visible light was strongly attenuated in the outer 0.2 mm of the tissue but was nearly constant for the subsequent 1.0 mm of photosynthetic tissue. Far-red scalar irradiance at 750 nm increased below the tissue surface to a maximum of 200% of incident irradiance at 1.2 mm depth due...

Hydrothermal liquefaction of Gracilaria gracilis and Cladophora glomerata macro-algae for biocrude production.

Science.gov (United States)

Parsa, Mehran; Jalilzadeh, Hamoon; Pazoki, Maryam; Ghasemzadeh, Reza; Abduli, MohammadAli

2018-02-01

The potential of Gracilaria gracilis (G. gracilis) and Cladophora glomerata (C. glomerata) macro-algae species harvested from Caspian Sea for biocrude oil production under Hydrothermal Liquefaction (HTL) reaction at 350 °C and 15 min has been investigated. Furthermore, the effect of using recycled aqueous phase as the HTL reaction solvent was studied. The biocrude yield for G. gracilis and C. glomerata was 15.7 and 16.9 wt%, respectively with higher heating value (HHV) of 36.01 and 33.06 MJ/kg. The sources of each existing component in bio-oil were identified by GC-MS based on their suggested reaction pathways. Moreover, after two series of aqueous solution recycling, experiments showed that the bio-oil yield significantly increased compared with the initial condition. This increasing directly relates with recovery of carbon content from the aqueous solution residue. Copyright © 2017. Published by Elsevier Ltd.

Diversity and abundance of the bacterial community of the red Macroalga Porphyra umbilicalis: did bacterial farmers produce macroalgae?

Directory of Open Access Journals (Sweden)

Lilibeth N Miranda

Full Text Available Macroalgae harbor microbial communities whose bacterial biodiversity remains largely uncharacterized. The goals of this study were 1 to examine the composition of the bacterial community associated with Porphyra umbilicalis Kützing from Schoodic Point, ME, 2 determine whether there are seasonal trends in species diversity but a core group of bacteria that are always present, and 3 to determine how the microbial community associated with a laboratory strain (P.um.1 established in the presence of antibiotics has changed. P. umbilicalis blades (n = 5, fall 2010; n = 5, winter 2011; n = 2, clonal P.um.1 were analyzed by pyrosequencing over two variable regions of the 16 S rDNA (V5-V6 and V8; 147,880 total reads. The bacterial taxa present were classified at an 80% confidence threshold into eight phyla (Bacteroidetes, Proteobacteria, Planctomycetes, Chloroflexi, Actinobacteria, Deinococcus-Thermus, Firmicutes, and the candidate division TM7. The Bacteroidetes comprised the majority of bacterial sequences on both field and lab blades, but the Proteobacteria (Alphaproteobacteria, Gammaproteobacteria were also abundant. Sphingobacteria (Bacteroidetes and Flavobacteria (Bacteroidetes had inverse abundances on natural versus P.um.1 blades. Bacterial communities were richer and more diverse on blades sampled in fall compared to winter. Significant differences were observed between microbial communities among all three groups of blades examined. Only two OTUs were found on all 12 blades, and only one of these, belonging to the Saprospiraceae (Bacteroidetes, was abundant. Lewinella (as 66 OTUs was found on all field blades and was the most abundant genus. Bacteria from the Bacteroidetes, Proteobacteria and Planctomycetes that are known to digest the galactan sulfates of red algal cell walls were well-represented. Some of these taxa likely provide essential morphogenetic and beneficial nutritive factors to P. umbilicalis and may have had

Coral reef degradation and metabolic performance of the scleractinian coral Porites lutea under anthropogenic impact along the NE coast of Hainan Island, South China Sea

KAUST Repository

Roder, Cornelia; Wu, Zhongjie; Richter, Claudio; Zhang, Jing

2013-01-01

Hainan's coast provides favorable climatic, geochemical and biogeographic conditions for the development of extensive coral reefs in China. Observations in five reefs along the NE coast of Hainan showed, however, that the overall density of mobile macrofauna is low and key functional groups such as browsing, scraping or excavating herbivore fish are missing altogether. Coral diseases, partial mortality or tissue degradation are abundant and growth of macroalgal space competitors extensive. Signs of eutrophication, siltation and destructive fishing practices are evident resulting in a strongly altered environment unfavorable for coral recruitment success and survival. Acclimation to the anthropogenically altered conditions in the massive coral Porites lutea occurs at the cost of a decreased photosynthesis: respiration ratio reducing the regenerative capacity of these key framebuilding organisms. Even though, on the organismal level, corals are able to cope with these stressful conditions, a shift is imminent on the ecosystem level from a coral reef to a macroalgae-dominated community if land-based disturbance prevails unabated. © 2012 Elsevier Ltd.

Coral reef degradation and metabolic performance of the scleractinian coral Porites lutea under anthropogenic impact along the NE coast of Hainan Island, South China Sea

KAUST Repository

Roder, Cornelia

2013-04-01

Hainan\\'s coast provides favorable climatic, geochemical and biogeographic conditions for the development of extensive coral reefs in China. Observations in five reefs along the NE coast of Hainan showed, however, that the overall density of mobile macrofauna is low and key functional groups such as browsing, scraping or excavating herbivore fish are missing altogether. Coral diseases, partial mortality or tissue degradation are abundant and growth of macroalgal space competitors extensive. Signs of eutrophication, siltation and destructive fishing practices are evident resulting in a strongly altered environment unfavorable for coral recruitment success and survival. Acclimation to the anthropogenically altered conditions in the massive coral Porites lutea occurs at the cost of a decreased photosynthesis: respiration ratio reducing the regenerative capacity of these key framebuilding organisms. Even though, on the organismal level, corals are able to cope with these stressful conditions, a shift is imminent on the ecosystem level from a coral reef to a macroalgae-dominated community if land-based disturbance prevails unabated. © 2012 Elsevier Ltd.

Metal-macrofauna interactions determine microbial community structure and function in copper contaminated sediments.

Science.gov (United States)

Mayor, Daniel J; Gray, Nia B; Elver-Evans, Joanna; Midwood, Andrew J; Thornton, Barry

2013-01-01

Copper is essential for healthy cellular functioning, but this heavy metal quickly becomes toxic when supply exceeds demand. Marine sediments receive widespread and increasing levels of copper contamination from antifouling paints owing to the 2008 global ban of organotin-based products. The toxicity of copper will increase in the coming years as seawater pH decreases and temperature increases. We used a factorial mesocosm experiment to investigate how increasing sediment copper concentrations and the presence of a cosmopolitan bioturbating amphipod, Corophium volutator, affected a range of ecosystem functions in a soft sediment microbial community. The effects of copper on benthic nutrient release, bacterial biomass, microbial community structure and the isotopic composition of individual microbial membrane [phospholipid] fatty acids (PLFAs) all differed in the presence of C. volutator. Our data consistently demonstrate that copper contamination of global waterways will have pervasive effects on the metabolic functioning of benthic communities that cannot be predicted from copper concentrations alone; impacts will depend upon the resident macrofauna and their capacity for bioturbation. This finding poses a major challenge for those attempting to manage the impacts of copper contamination on ecosystem services, e.g. carbon and nutrient cycling, across different habitats. Our work also highlights the paucity of information on the processes that result in isotopic fractionation in natural marine microbial communities. We conclude that the assimilative capacity of benthic microbes will become progressively impaired as copper concentrations increase. These effects will, to an extent, be mitigated by the presence of bioturbating animals and possibly other processes that increase the influx of oxygenated seawater into the sediments. Our findings support the move towards an ecosystem approach for environmental management.

Metal-macrofauna interactions determine microbial community structure and function in copper contaminated sediments.

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Daniel J Mayor

Full Text Available Copper is essential for healthy cellular functioning, but this heavy metal quickly becomes toxic when supply exceeds demand. Marine sediments receive widespread and increasing levels of copper contamination from antifouling paints owing to the 2008 global ban of organotin-based products. The toxicity of copper will increase in the coming years as seawater pH decreases and temperature increases. We used a factorial mesocosm experiment to investigate how increasing sediment copper concentrations and the presence of a cosmopolitan bioturbating amphipod, Corophium volutator, affected a range of ecosystem functions in a soft sediment microbial community. The effects of copper on benthic nutrient release, bacterial biomass, microbial community structure and the isotopic composition of individual microbial membrane [phospholipid] fatty acids (PLFAs all differed in the presence of C. volutator. Our data consistently demonstrate that copper contamination of global waterways will have pervasive effects on the metabolic functioning of benthic communities that cannot be predicted from copper concentrations alone; impacts will depend upon the resident macrofauna and their capacity for bioturbation. This finding poses a major challenge for those attempting to manage the impacts of copper contamination on ecosystem services, e.g. carbon and nutrient cycling, across different habitats. Our work also highlights the paucity of information on the processes that result in isotopic fractionation in natural marine microbial communities. We conclude that the assimilative capacity of benthic microbes will become progressively impaired as copper concentrations increase. These effects will, to an extent, be mitigated by the presence of bioturbating animals and possibly other processes that increase the influx of oxygenated seawater into the sediments. Our findings support the move towards an ecosystem approach for environmental management.

Distribuição horizontal da macrofauna bentônica na praia do Cassino, extremo sul do Brasil

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Luciano Peyrer das Neves

2012-09-01

Full Text Available A distribuição horizontal da macrofauna bentônica na praia do Cassino, Rio Grande do Sul, Brasil foi estudada durante o período de um ano (junho 2004 a maio de 2005 com base em coletas mensais. Foram escolhidos três locais, com 50 m de distância um do outro, sendo que em cada local foram fundeadas três transversais 2 m equidistantes. Cada transversal estendeu-se da base das dunas primárias até aproximadamente 1 m de profundidade no infralitoral. A distância dos níveis de coleta em cada transversal foi de 20 m até o limite superior da zona de varrido, a partir do qual a distância foi de 10 m. Em algumas ocasiões foi evidenciada variação espacial horizontal de alguns dos principais táxons, bem como da comunidade bentônica dentro de uma escala de 50 m e 100 m. Esta variação foi provavelmente reflexo da ação das marés meteorológicas que causam abrupta elevação do nível do mar.

Health-promoting ingredients from four selected Azorean macroalgae.

Science.gov (United States)

Paiva, Lisete; Lima, Elisabete; Neto, Ana Isabel; Marcone, Massimo; Baptista, José

2016-11-01

This study presents, for the first time, the nutritional and health promoting aspects of four selected Azorean macroalgae (Ulva compressa, Ulva rigida, Gelidium microdon and Pterocladiella capillacea) in terms of total lipids, fatty acids (FA) profile, n6/n3 and hypocholesterolemic (h)/hypercholesterolemic (H) FA ratios, minerals, total essential amino acids (AA), anti-ageing and anti-phenylketonuria AA content, coenzyme Q 10 , α-tocopherol, total phenolics, antioxidant properties and energy value, on a dry weight basis. The results revealed low lipid content (1.02-4.32%) but significant PUFA content (29.57-69.22% of total FA), suitable FA ratios (0.48-9.49 for n6/n3 and 1.26-4.22 for h/H), balanced macromineral ratios (0.27-1.91 for Na/K and 0.15-1.07 for Ca/Mg), appreciable amount of essential AA (45.27-58.13% of total AA), high amount of anti-ageing AA, low Phe content, coenzyme Q 10 (1.25-8.27μg/g), α-tocopherol (2.61-9.14mg/100g), high total phenolic content (27.70-55.07mg of gallic acid equivalents/g extract), significant free radical scavenging activity (29.32-47.73%) and valuable energy content (6.80-9.80kJ/g). A regular consumption of these algae either directly or through food supplements may improve human health or may have a protective effect on some diseases and ageing process. They can also be used for producing pharmaceuticals and cosmeceuticals with potential economic value. Copyright © 2016. Published by Elsevier Ltd.

Cadmium, copper and lead in macroalgae from the Veracruz Reef System, Gulf of Mexico: Spatial distribution and rainy season variability

International Nuclear Information System (INIS)

Horta-Puga, Guillermo; Cházaro-Olvera, Sergio; Winfield, Ignacio; Avila-Romero, Marisol; Moreno-Ramírez, Margarita

2013-01-01

Highlights: ► Cd, Cu, and Pb were determined in macroalgae from Veracruz Reefs, Gulf of Mexico. ► Mean concentrations were lower or similar to those from other coastal areas. ► Cd and Pb levels are controlled by fluvial discharge. ► Sediment scavenging also controls environmental trace metal levels. ► Pb environmental concentrations have been decreasing in the lasts two decades. -- Abstract: This study focused on the spatial distribution of trace metals in the Veracruz Reef System in the Southern Gulf of Mexico, and its variability in the early (July) and late (September) rainy season of 2008, by analyzing the concentration of Cd, Cu and Pb in benthic macroalgae. Mean concentrations are lower (Pb 295 ± 347 ng g −1 , Cd 17.9 ± 15.0 ng g −1 ), or similar (Cu 3.4 ± 4.5 μg g −1 ) to those reported from other coastal areas. Cd and Pb concentrations are influenced by the discharge of the Jamapa River, evidencing a fluvial control on coastal trace metal levels. Also, Cd and Cu concentrations were lower in the late rainy season, when there is a high load of suspended sediments derived from fluvial discharge, which probably adsorb dissolved metals decreasing their bioavailability. Pb concentrations have been decreasing in the last two decades in the SGM, after the banning of leaded-gasoline in the late 20th century

Ecophysiology of Antarctic macroalgae: effects of environmental light conditions on photosynthetic metabolism Ecofisiología de macroalgas marinas antárticas: efectos de las condiciones de luz sobre el metabolismo fotosintético

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I. GÓMEZ

2001-06-01

Full Text Available Daylength is the major environmental factor affecting the seasonal photosynthetic performance of Antarctic macroalgae. For example, the "season anticipation" strategy of large brown algae such as Ascoseira mirabilis and Desmarestia menziesii are based on the ability of their photosynthetic apparatus to make use of the available irradiance at increasing daylengths in late winter-spring. The seasonal development and allocation of biomass along the lamina of A. mirabilis are related to a differential physiological activity in the plant. Thus, intra-thallus differentiation in O2-based photosynthesis and carbon fixation represents a morpho-functional adaptation that optimizes conversion of radiant energy to primary productivity. In Desmarestia menziesii, reproductive phases show different photosynthetic characteristics. Small gametophytes and early stages of sporophytes, by virtue of their fine morphology, have a high content of pigments per weight unit, a high photosynthetic efficiency, very low light requirements for photosynthesis, and they are better suited to dim light conditions than adult sporophytes. This strategy ensures the completion of the life-cycle under seasonally changing light conditions. Low light requirements for growing and photosynthesizing are developed to cope with Antarctic seasonality and constitute adaptations to expand depth zonation of macroalgae. No differences in net Pmax and photosynthetic efficiency (a among algae growing at depths between 10 and 30 m, suggest a low potential for photoacclimation enabling algae to grow over a wide range of prevailing light conditions. However, shortenings in the daily period during which plants are exposed to saturation irradiances for photosynthesis (Hsat and low carbon balance (daily P/R ratios at depths close to or larger than 30 m negatively affect primary productivity. In general, photosynthetic rates of Antarctic macroalgae at 0 °C are comparable to those measured in species

Levels of some Trace Metals in Macroalgae from the Red Sea in Egypt

International Nuclear Information System (INIS)

Aboul-Naga, Wafiqa Mohamed

2005-01-01

The concentrations of iron (Fe), Zinc (Zn), manganese (Mn), Copper (Cu), chromium (Cr), nickel (Ni), and cobalt (Co) in ten macroalgae species from the Red Sea coastal water varied widely and also the trend of abundance of each metal also differed from one group to another. Concentration factors varied among species for iron (Fe) copper (Cu) manganese (Mn), but with iron (Fe) showing generally high concentration factors. Highly significant (P<0.05) relationships were found between manganese (Mn) and Nickel (Ni), and, Zinc (Zn) and copper (Cu). Moreover, moderate correlations were observed between manganese (Mn) and iron (Fe) and chromium (Cr), indicating that manganese (Mn) is the most accumulated metal in the macro algae of the Red Sea. In spite of the level of trace metals in the macro algae of the Red Sea. In spite of the level of trace metals in the macro algae, dominance is moderate relative to other sea areas subjected to intensive pollution. That is, the results indicated a nonpolluted environment. (author)

[Use of macroalgae for the evaluation of organic pollution in the Preto river, northwest of São Paulo State].

Science.gov (United States)

Necchi Júnior, O; Branco, H Z; Dip, M R

1994-01-01

The Preto River, located in the northwest of São Paulo State, receives a total wastewater load of 15.150 kg DBO day-1, from which 13.685 kg DBO day-1 (90.5%) corresponds to domestic sewage, and the city of São José do Rio Preto contributes with 12.400 kg DBO day-1 (90% of domestic sewage). During the period from August 1990 through January 1991, monthly sampling was carried out to evaluate the use of macroalgae as bioindicator of organic pollution. Five sampling sites were established along the main river and the following variables were analised: temperature, conductance, turbidity, dissolved oxygen, BOD, COD, total and fecal coliforms, and composition and abundance of macroalgal communities. Data were submitted to analysis of variance, correlation coefficient, cluster analysis (four different approaches) and converted to biological indices (species deficit, relative pollution, saprobity, diversity and uniformity indices). A wide range in water quality was found (particularly for conductance, oxygen, BOD and COD) among the sampling sites, which were classified into three groups (polluted, moderately polluted and unpolluted/weakly polluted). As regards the occurrence and abundance of macroalgae the Rhodophyta were found only in unpolluted or weakly polluted sites, whereas Cyanophyta occurred mostly under high pollution load; the Chlorophyta species were observed under a wide range of conditions. Among the biological indices, saprobity was the most sensitive and correlated to all water variables and the other indices. Cluster analyses showed that the composition of macroalgal communities was consistent with the levels of organic pollution in the Preto River.

Screening of antimicrobial activity of macroalgae extracts from the Moroccan Atlantic coast.

Science.gov (United States)

El Wahidi, M; El Amraoui, B; El Amraoui, M; Bamhaoud, T

2015-05-01

The aim of this work is the screening of the antimicrobial activity of seaweed extracts against pathogenic bacteria and yeasts. The antimicrobial activity of the dichloromethane and ethanol extracts of ten marine macroalgae collected from the Moroccan's Atlantic coast (El-Jadida) was tested against two Gram+ (Bacillus subtilis and Staphylococcus aureus) and two Gram- (Escherichia coli and Pseudomonas aeruginosa) human pathogenic bacteria, and against two pathogenic yeasts (Candida albicans and Cryptococcus neoformans) using the agar disk-diffusion method. Seven algae (70%) of ten seaweeds are active against at least one pathogenic microorganisms studied. Five (50%) are active against the two studied yeast with an inhibition diameter greater than 15 mm for Cystoseira brachycarpa. Six (60%) seaweeds are active against at least one studied bacteria with five (50%) algae exhibiting antibacterial inhibition diameter greater than 15 mm. Cystoseira brachycarpa, Cystoseira compressa, Fucus vesiculosus, and Gelidium sesquipedale have a better antimicrobial activity with a broad spectrum antimicrobial and are a potential source of antimicrobial compounds and can be subject of isolation of the natural antimicrobials. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Macroflora and macrofauna associated with sumerged roots of Rhizophora mangle (Rhizophoraceae, in the Tampamachoco lagoon, Veracruz, Mexico

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Edith Lucas M

2018-03-01

Full Text Available In the Tampamachoco lagoon, Veracruz, the diversity, abundance and similarity of the floristic and faunistic composition associated to R. mangle roots were determined; four sampling sites were distributed in the northern, central and southern portions of the lagoon, and 10 mangrove roots were searched for each site for collection, identification and quantification of the organisms. With the quantitative information, species richness, Simpson dominance, fairness and true diversity were estimated, and similarities/dissimilarities were determined between the sampling areas by sorting and ordering analysis. Ten species of algae, 26 invertebrate species and one vertebrate species were identified, totaling 37 species. A total of 10260 macrofaunal organisms were quantified, with an average abundance of 85.5 ± 71.2 ind/root being estimated. The most abundant species were Amphibalanus sp., Ischadium recurvum and Crassostrea rhizophorae. The remarkable abundance in the northern zone was significantly different from the central and southern zones. In general, the macrofaunistic community was equitable, and presented true diversity values from 2.8 to 3.7 effective species. The composition and abundance of macrofauna were similar in the three sampling zones. The submerged roots of R. mangle play a key role in the Tampamachoco lagoon by providing habitats for various aquatic organisms.

Estudo da dinâmica de macroalgas em flutuantes de duas comunidades ribeirinhas na bacia do Tarumã-Mirim (área rural de Manaus/AM por alunos do ensino fundamental / STUDY OF THE DYNAMICS OF FLOATING MACROALGAL IN TWO COMMUNITIES IN RIPARIAN BASIN TARUMÃ-MIRIM (RURAL AREA OF MANAUS / AM BY STUDENTS OF BASIC EDUCATION

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Domitila Pascoaloto

2010-05-01

Full Text Available O presente estudo faz parte de um projeto voltado para Educação ambiental na bacia do Tarumã-Mirim. Em abril/2008 seis alunos do ensino fundamental acompanharam, por quinze dias, a presença de macroalgas em três flutuantes da comunidade Nossa Senhora de Fátima, a flutuação do nível do igarapé nesses flutuantes e a distância entre a sede da comunidade o porto principal. Também foi feito o levantamento das macroalgas na comunidade Nossa Senhora do Livramento. Macroalgas estiveram presentes em todos os locais, em ambas as comunidades. A distância entre a sede da comunidade e o flutuante principal variou 1,4 metros; a variação do nível de água no igarapé foi de 0,33 a 0,92 metros. As características químicas da água foram semelhantes (ácidas e pouco mineralizadas. Os alunos verificaram que a presença das macroalgas esteve mais relacionada com as características físicas dos locais (substrato estável e incidência de luz solar.

Direct evidence for coastal iodine particles from Laminaria macroalgae – linkage to emissions of molecular iodine

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G. McFiggans

2004-01-01

Full Text Available Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN. Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2, (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003, provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000 and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical. When small, those formed in the molecular iodine system swell only moderately when exposed to increased humidity environments, and swell progressively less with increasing size; this behaviour occurs whether they are formed in dry or humid environments, in contrast to those in the CH2I2 system. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular

Diversidade e padrão de distribuição das macroalgas verdes da bacia Potiguar, Rio Grande do Norte, Nordeste do Brasil

OpenAIRE

Cocentino, Adilma de Lourdes Montenegro; Fujii, Mutue Toyota; Reis, Thiago Nogueira de Vasconcelos; Guimarães-Barros, Nathalia Cristina; Rocha, Marcia de França; Neumann-Leitão, Sigrid

2010-01-01

Diversity and distribution pattern of the infralittoral green macroalgae at Potiguar basin, Rio Grande do Norte, Northeastern Brazil were analyzed from material collected at depths varying from 2 to 100 m. Collections were carried out with two types of dredges during four campaigns: July 2002, May and November 2003 and May 2004 at 43 stations. Chlorophyta is represented by 54 species, five varieties and three forms. The most representative family is Caulerpaceae, and the most diverse genus is...

Comparative study on the pyrolysis behaviour and kinetics of two macroalgae biomass (Gracilaria changii and Gelidium pusillum) by thermogravimetric analysis

Science.gov (United States)

Roslee, A. N.; Munajat, N. F.

2017-10-01

Macroalgae are often referred as seaweed and could be significant biomass resource for the production of numerous energy carriers including biofuels. In this study, the chemical composition of Gracilaria changii (G. changii) and Gelidium pusillum (G. pusillum) were determined through proximate and ultimate analysis and the thermal degradation behaviour of G. changii and G. pusillum were investigated via thermogravimetric analysis (TGA) in determining the important main composition to be considered as biomass fuels. It has found the pyrolysis of G. changii and G. pusillum consists of three stages and stage II is the main decomposition stage with major mass loss of around 52.16% and 44.42%, respectively. The TGA data were then used for determination of kinetic parameters of the pyrolysis process using three model-free methods: Kissinger, Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO). The apparent activation energy calculated by using Kissinger method for G. changii was lower than G. Pusillum, i.e.173.12 kJ/mol and 193.22 kJ/mol, respectively. The activation energies calculated from KAS and FWO methods were increased with increasing the pyrolysis conversion with average activation energies of 172.32 kJ/mol and 181.19 kJ/mol for G. changii while for G. pusillum (177.42 kJ/mol and 187.4 kJ/mol). G. pusillum has lower and wider distribution of activation energy and revealed that the pyrolysis process for G. changii was easier than G. pusillum. These data provide information for further application for designing and modelling in thermochemical conversion system of macroalgae biomass.

Nitrogen fixation rates associated with the invasive macroalgae Sargassum horneri around Catalina Island, CA

Science.gov (United States)

DeLiberto, A.

2016-02-01

Nitrogen fixation is an important process which allows organisms access to biologically unavailable dinitrogen gas. Bacteria, known as diazotrophs use the enzyme nitrogenase to convert N2 to NH3. These bacteria, including certain species of heterotrophic bacteria and cyanobacteria, can be symbiotically associated with marine macroalgae, facilitating nutrient cycling in oligotrophic regions. As many species within the genera Sargassum are associated with nitrogen fixation, this study hypothesized that nitrogenase activity would be associated with the benthic invasive Sargassum horneri on Catalina Island. In the past decade, Sargassum horneri, an invasive from Japan, has spread throughout the waters around Catalina Island. Using the acetylene reduction procedure using flame ionization detection, initial nitrogenase activity of S. horneri sampled from Indian Rock was observed. Nitrogen fixation rates increased with decomposition, particularly in dark/anaerobic treatments, suggesting the presence of heterotrophic bacteria. In addition, acetate additions greatly increase nitrogen fixation rates, once again indicating heterotrophic nitrogen fixing bacteria.

Differences in meiofauna communities with sediment depth are greater than habitat effects on the New Zealand continental margin: implications for vulnerability to anthropogenic disturbance

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Norliana Rosli

2016-07-01

Full Text Available Studies of deep-sea benthic communities have largely focused on particular (macro habitats in isolation, with few studies considering multiple habitats simultaneously in a comparable manner. Compared to mega-epifauna and macrofauna, much less is known about habitat-related variation in meiofaunal community attributes (abundance, diversity and community structure. Here, we investigated meiofaunal community attributes in slope, canyon, seamount, and seep habitats in two regions on the continental slope of New Zealand (Hikurangi Margin and Bay of Plenty at four water depths (700, 1,000, 1,200 and 1,500 m. We found that patterns were not the same for each community attribute. Significant differences in abundance were consistent across regions, habitats, water and sediment depths, while diversity and community structure only differed between sediment depths. Abundance was higher in canyon and seep habitats compared with other habitats, while between sediment layer, abundance and diversity were higher at the sediment surface. Our findings suggest that meiofaunal community attributes are affected by environmental factors that operate on micro- (cm to meso- (0.1–10 km, and regional scales (> 100 km. We also found a weak, but significant, correlation between trawling intensity and surface sediment diversity. Overall, our results indicate that variability in meiofaunal communities was greater at small scale than at habitat or regional scale. These findings provide new insights into the factors controlling meiofauna in these deep-sea habitats and their potential vulnerability to anthropogenic activities.

Thermochemical hydrolysis of macroalgae Ulva for biorefinery: Taguchi robust design method

Science.gov (United States)

Jiang, Rui; Linzon, Yoav; Vitkin, Edward; Yakhini, Zohar; Chudnovsky, Alexandra; Golberg, Alexander

2016-06-01

Understanding the impact of all process parameters on the efficiency of biomass hydrolysis and on the final yield of products is critical to biorefinery design. Using Taguchi orthogonal arrays experimental design and Partial Least Square Regression, we investigated the impact of change and the comparative significance of thermochemical process temperature, treatment time, %Acid and %Solid load on carbohydrates release from green macroalgae from Ulva genus, a promising biorefinery feedstock. The average density of hydrolysate was determined using a new microelectromechanical optical resonator mass sensor. In addition, using Flux Balance Analysis techniques, we compared the potential fermentation yields of these hydrolysate products using metabolic models of Escherichia coli, Saccharomyces cerevisiae wild type, Saccharomyces cerevisiae RN1016 with xylose isomerase and Clostridium acetobutylicum. We found that %Acid plays the most significant role and treatment time the least significant role in affecting the monosaccharaides released from Ulva biomass. We also found that within the tested range of parameters, hydrolysis with 121 °C, 30 min 2% Acid, 15% Solids could lead to the highest yields of conversion: 54.134-57.500 gr ethanol kg-1 Ulva dry weight by S. cerevisiae RN1016 with xylose isomerase. Our results support optimized marine algae utilization process design and will enable smart energy harvesting by thermochemical hydrolysis.

Thermochemical hydrolysis of macroalgae Ulva for biorefinery: Taguchi robust design method.

Science.gov (United States)

Jiang, Rui; Linzon, Yoav; Vitkin, Edward; Yakhini, Zohar; Chudnovsky, Alexandra; Golberg, Alexander

2016-06-13

Understanding the impact of all process parameters on the efficiency of biomass hydrolysis and on the final yield of products is critical to biorefinery design. Using Taguchi orthogonal arrays experimental design and Partial Least Square Regression, we investigated the impact of change and the comparative significance of thermochemical process temperature, treatment time, %Acid and %Solid load on carbohydrates release from green macroalgae from Ulva genus, a promising biorefinery feedstock. The average density of hydrolysate was determined using a new microelectromechanical optical resonator mass sensor. In addition, using Flux Balance Analysis techniques, we compared the potential fermentation yields of these hydrolysate products using metabolic models of Escherichia coli, Saccharomyces cerevisiae wild type, Saccharomyces cerevisiae RN1016 with xylose isomerase and Clostridium acetobutylicum. We found that %Acid plays the most significant role and treatment time the least significant role in affecting the monosaccharaides released from Ulva biomass. We also found that within the tested range of parameters, hydrolysis with 121 °C, 30 min 2% Acid, 15% Solids could lead to the highest yields of conversion: 54.134-57.500 gr ethanol kg(-1) Ulva dry weight by S. cerevisiae RN1016 with xylose isomerase. Our results support optimized marine algae utilization process design and will enable smart energy harvesting by thermochemical hydrolysis.

Uptake of PCBs contained in marine sediments by the green macroalga Ulva rigida.

Science.gov (United States)

Cheney, Donald; Rajic, Ljiljana; Sly, Elizabeth; Meric, Dogus; Sheahan, Thomas

2014-11-15

The uptake of PCBs contained in marine sediments by the green macroalga Ulva rigida was investigated in both laboratory and field experiments. Under laboratory conditions, total PCBs (tPCBs) uptake was significantly greater in live vs dead plants. The concentration of tPCB taken up in live plants was greatest in the first 24h (1580 μg kg(-1) dry weight), and then increased at a lower rate from day 2 to 14. Dead plants had a significantly lower tPCB concentration after 24h (609 μg kg(-1) dry weight) and lower uptake rate through day 14. Lesser chlorinated PCB congeners (below 123) made up the majority of PCBs taken up. Congener composition in both laboratory and field experiments was correlated to congener logKow value and sediment content. Field experiments showed that Ulva plants could concentrate PCBs to 3.9 mg kg(-1) in 24h. Thus, U. rigida is capable of removing PCBs in sediments at a rapid rate. Copyright © 2014 Elsevier Ltd. All rights reserved.

Physiological responses of macroalga Gracilaria lemaneiformis (Rhodophyta) to UV-B radiation exposure

Science.gov (United States)

Zhu, Lin; Xiao, Hui; Wang, Ying; Jian, Xiaoyang; Zhang, Zhipeng; Zhang, Huanxin; Tang, Xuexi

2015-03-01

This paper aims to evaluate the effects of ultraviolet-B radiation (UVBR) on Gracilaria lemaneiformis, a commercial red macroalga and an important source of agar. To study the in-vitro effect of UVBR on G. lemaneiformis, this plant was cultivated and exposed to photosynthetically active radiation (PAR) at 40 μmol photons/(m2 ·s) and enhanced UVBR (0, 0.36, 0.72, 1.08, 1.44, and 1.80 kJ/(m2 ·d)) for 13 days. The samples were processed for histochemical analysis, and the growth rate, photosynthetic pigment contents, photosynthetic performance, reactive oxygen species levels, membrane permeability, malonyl dialdehyde contents and antioxidant capacity of G. lemaneiformis were investigated. After 13 days of exposure to PAR+UVBR, G. lemaneiformis showed photodamage and photoinhibition of photosynthetic pigments (chlorophyll a and phycoerythrin), leading to a decreased photosynthetic efficiency. Further, there was a corresponding decrease in the relative growth rates and depigmentation and partial necrosis of the apical segments were noted after exposure to PAR+UVBR. Additionally, UVBR induced excess production of superoxide radicals and hydrogen peroxide, eliciting a marked cellular membrane damage and antioxidative response.

Toxicity of tire wear particle leachate to the marine macroalga, Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Turner, Andrew, E-mail: aturner@plymouth.ac.u [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Rice, Lynsey [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

2010-12-15

Tire wear particles filed from the treads of end-of-life vehicle tires have been added to sea water to examine the release of Zn and the toxicity of the resulting leachate and dilutions thereof to the marine macroalga, Ulva lactuca. Zinc release appeared to be diffusion-controlled, with a conditional rate constant of 5.4 {mu}g[L(h){sup 1/2}]{sup -1}, and about 1.6% of total Zn was released after 120 h incubation. Exposure to increasing concentrations of leachate resulted in a non-linear reduction in the efficiency of photochemical energy conversion of U. lactuca and, with the exception of the undiluted leachate, increasing accumulation of Zn. Phototoxicity was significantly lower on exposure to equivalent concentrations of Zn added as Zn(NO{sub 3}){sub 2}, suggesting that organic components of leachate are largely responsible for the overall toxicity to the alga. Given the ubiquity and abundance of TWP in urban coastal sediments, the generation, biogeochemistry and toxicity of tire leachate in the marine setting merit further attention. - Tire wear leachate is toxic to Ulva lactuca and zinc is a potential bioindicator of leachate contamination in urban marine systems.

Functional groupings and food web of an artificial reef used for sea cucumber aquaculture in northern China

Science.gov (United States)

Xu, Qinzeng; Zhang, Libin; Zhang, Tao; Zhang, Xuelei; Yang, Hongsheng

2017-01-01

Artificial reef is considered as a useful tool to remodel habitats in coastal and estuarine area. Some artificial reefs (ARs) were conducted in Shandong Peninsula for sea cucumber Apostichopus japonicus integrated multi-trophic aquaculture (IMTA). Little is known about the main feeding type and food resources of living organisms in this IMTA ecosystem. Neither is the information about other animals competing food with A. japonicus. Functional group (FG) and their food resources of mobile organisms and epifauna in ARs area were investigated. There were three types of food resources and five FGs within two trophic levels in studied area. Particle organic matter (POM), seaweed detritus and sediment were considered to be the main food resources. The first three FGs were primary consumers and were mainly epifauna, while the other two FGs were secondary consumers. FG 1 species were filter feeders, and group 2 was all deposit feeders and A. japonicus was in this group. FG 2 contained few species and this indicated that A. japonicus had few food competitors. FG 3 contained most epifauna species which were detritus feeders and this result implied that the artificial oyster shell reed can retain detritus effectively. The food sources of group 4 were complex. Species of group 5, mostly fish, occupied the top trophic level and fed primarily on species of FG 1 and FG 2. This kind of ARs can retain detritus effectively and provide suitable habitat to epifauna and surrounding natural fauna community.

Zinc concentrations in marine macroalgae and a lichen from western Ireland in relation to phylogenetic grouping, habitat and morphology

International Nuclear Information System (INIS)

Stengel, Dagmar B.; Macken, Ailbhe; Morrison, Liam; Morley, Nicholas

2004-01-01

Zinc concentrations in 19 species of marine macroalgae and a lichen from western Ireland (Spiddal, Co. Galway) were analysed by atomic absorption spectrophotometry. Algae were collected from a single site but occupied different shore levels and belonged to distinct phylogenetic groupings and to different (previously recognised) morphological groups. Concentrations ranged from 15-115 μg g -1 dry weight. The greatest variation in concentration occurred amongst the red algal species, containing both maximum and minimum concentrations. Zn concentrations in brown and green algae were generally lower than those in red algae. When grouped according to thallus morphology, thin, branched sheets (which consisted mainly of red algae) contained the highest Zn concentrations. In filamentous algae, Zn levels were higher than in thick-leathery or coarsely branched algae. However, all green algal species examined had similar Zn concentrations, despite their different morphologies. In brown algae, the highest Zn levels were detected in mid-shore fucoids (Fucus vesiculosus and Fucus serratus), while thicker, subtidal and low-shore brown algae (Laminaria digitata, Halydris siliquosa) exhibited lower Zn concentrations. The lowest Zn concentrations were detected in high-intertidal species (Fucus spiralis, Pelvetia canaliculata), the only marine lichen examined (Ramalina siliquosa) and a red crustose alga (Corallina officinalis). In all morphological groups, red algal representatives contained relatively higher levels of Zn, the exception being Corallina officinalis. Zn levels in 4 species from a second, estuarine site in Galway Bay exhibited the same relative differences amongst species, but were all consistently higher than in algae from Spiddal. It is concluded that Zn accumulation in macroalgae is closely related to ecological growth strategies, following a functional-form model. However, the phylogenetic origin of species which determines carbohydrate and phenol composition, and

Zinc concentrations in marine macroalgae and a lichen from western Ireland in relation to phylogenetic grouping, habitat and morphology

Energy Technology Data Exchange (ETDEWEB)

Stengel, Dagmar B.; Macken, Ailbhe; Morrison, Liam; Morley, Nicholas

2004-05-01

Zinc concentrations in 19 species of marine macroalgae and a lichen from western Ireland (Spiddal, Co. Galway) were analysed by atomic absorption spectrophotometry. Algae were collected from a single site but occupied different shore levels and belonged to distinct phylogenetic groupings and to different (previously recognised) morphological groups. Concentrations ranged from 15-115 {mu}g g{sup -1} dry weight. The greatest variation in concentration occurred amongst the red algal species, containing both maximum and minimum concentrations. Zn concentrations in brown and green algae were generally lower than those in red algae. When grouped according to thallus morphology, thin, branched sheets (which consisted mainly of red algae) contained the highest Zn concentrations. In filamentous algae, Zn levels were higher than in thick-leathery or coarsely branched algae. However, all green algal species examined had similar Zn concentrations, despite their different morphologies. In brown algae, the highest Zn levels were detected in mid-shore fucoids (Fucus vesiculosus and Fucus serratus), while thicker, subtidal and low-shore brown algae (Laminaria digitata, Halydris siliquosa) exhibited lower Zn concentrations. The lowest Zn concentrations were detected in high-intertidal species (Fucus spiralis, Pelvetia canaliculata), the only marine lichen examined (Ramalina siliquosa) and a red crustose alga (Corallina officinalis). In all morphological groups, red algal representatives contained relatively higher levels of Zn, the exception being Corallina officinalis. Zn levels in 4 species from a second, estuarine site in Galway Bay exhibited the same relative differences amongst species, but were all consistently higher than in algae from Spiddal. It is concluded that Zn accumulation in macroalgae is closely related to ecological growth strategies, following a functional-form model. However, the phylogenetic origin of species which determines carbohydrate and phenol composition

The Macroalgae Biorefinery for Production of Bioethanol and Fish Feed from the Two Brown Algae: Laminaria Digitata and Saccharina Latissima

DEFF Research Database (Denmark)

Hou, Xiaoru; Bjerre, Anne-Belinda; Hansen, Jonas Høeg

by ensiling (with lactic acid bacteria) or simple drying. Pretreatment was carried out using wet-milling and enzymatic hydrolysis in accordance with 1G bioethanol technology from corn. Different commercial enzyme mixtures for fully or partly hydrolysis of algae sugar polymers into monomers were tested...... and conversion of the differently pretreated macroalgae biomass into ethanol by fermentation were compared. The protein contents and nutrient salts in residues from ethanol fermentation trials were characterized for potential fish feed. A first-step scenario for sustainability and feasibility assessment...... will be presented for this innovative process of biorefining of value-added algae proteins derived directly through fermentation processes of algae sugars to bioenergy carriers....

Comparative composition, diversity and trophic ecology of sediment macrofauna at vents, seeps and organic falls.

Directory of Open Access Journals (Sweden)

Angelo F Bernardino

Full Text Available Sediments associated with hydrothermal venting, methane seepage and large organic falls such as whale, wood and plant detritus create deep-sea networks of soft-sediment habitats fueled, at least in part, by the oxidation of reduced chemicals. Biological studies at deep-sea vents, seeps and organic falls have looked at macrofaunal taxa, but there has yet to be a systematic comparison of the community-level attributes of sediment macrobenthos in various reducing ecosystems. Here we review key similarities and differences in the sediment-dwelling assemblages of each system with the goals of (1 generating a predictive framework for the exploration and study of newly identified reducing habitats, and (2 identifying taxa and communities that overlap across ecosystems. We show that deep-sea seep, vent and organic-fall sediments are highly heterogeneous. They sustain different geochemical and microbial processes that are reflected in a complex mosaic of habitats inhabited by a mixture of specialist (heterotrophic and symbiont-associated and background fauna. Community-level comparisons reveal that vent, seep and organic-fall macrofauna are very distinct in terms of composition at the family level, although they share many dominant taxa among these highly sulphidic habitats. Stress gradients are good predictors of macrofaunal diversity at some sites, but habitat heterogeneity and facilitation often modify community structure. The biogeochemical differences across ecosystems and within habitats result in wide differences in organic utilization (i.e., food sources and in the prevalence of chemosynthesis-derived nutrition. In the Pacific, vents, seeps and organic-falls exhibit distinct macrofaunal assemblages at broad-scales contributing to ß diversity. This has important implications for the conservation of reducing ecosystems, which face growing threats from human activities.

Photoinhibition in common atlantic macroalgae measured on site in Gran Canaria

Science.gov (United States)

Häder, D.-P.; Porst, M.; Lebert, M.

2001-03-01

The photosynthetic quantum yield was analysed in four common atlantic macroalgae, the Rhodophytes Gelidium arbuscula and Halopithys incurvus and the Phaeophytes Halopteris scoparia and Lobophora variegata in Gran Canaria, Canary Islands at their growth site. The fluorescence parameters were measured using a portable pulse amplitude modulated (PAM) fluorometer (PAM 2000) instrument and a diving PAM under water without removing the thalli from their growth sites. Solar radiation was monitored continuously above and under water during the whole experimental period using two three-channel dosimeters (European light dosimeter network; ELDONET) (Real Time Computer, Möhrendorf, Germany). These instruments measure solar radiation in three wavelength ranges, ultraviolet (UV)-A, UV-B and photosynthetic active radiation (PAR). In all four algae the effective photosynthetic quantum yield decreased significantly from the optimal values measured after dark adaptation due to exposure to 15 min solar radiation, but at least partially recovered subsequently in the shade within several hours. Increasing the exposure period to 30 min intensified the photoinhibition. In some algae no recovery was observed after this treatment and in others no significant recovery could be detected. Exposure to unfiltered solar radiation caused a significantly higher photoinhibition than PAR-only radiation or PAR plus UV-A. A substantial inhibition was found in all algae at their growth sites in the water column when the sun was at high angles, as measured with the diving PAM.

Ultrasound-enhanced rapid in situ transesterification of marine macroalgae Enteromorpha compressa for biodiesel production.

Science.gov (United States)

Suganya, Tamilarasan; Kasirajan, Ramachandran; Renganathan, Sahadevan

2014-03-01

In situ transesterification of Enteromorpha compressa algal biomass was carried out for the production of biodiesel. The maximum methyl esters (ME) yield of 98.89% was obtained using ultrasonic irradiation. Tetra hydro furan (THF) and acid catalyst (H2SO4) was found to be an appropriate co-solvent and catalyst for high free fatty acids (FFA) content E. compressa biomass to increase the efficiency of the reactive in situ process. The optimization study was conducted to obtain the maximum yield and it was determined as 30vol% of THF as a co-solvent, 10wt% of H2SO4, 5.5:1 ratio of methanol to algal biomass and 600rpm of mixing intensity at 65°C for 90min of ultrasonic irradiation time. The produced biodiesel was characterized by (1)H nuclear magnetic resonance spectroscopy ((1)H NMR) analysis. Kinetic studies revealed that the reaction followed the first-order reaction mechanism. Rapid in situ transesterification was found to be suitable technique to produce biodiesel from marine macroalgae feedstock. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biogas from Marine Macroalgae: a New Environmental Technology — Life Cycle Inventory for a Further LCA

Science.gov (United States)

Romagnoli, Francesco; Blumberga, Dagnija; Gigli, Emanuele

2010-01-01

The main goal of this paper is to analyze the innovative process of production of biogas (via fermentation processes) using marine macroalgae as feedstock in a pilot project plant in Augusta (Sicily, Italy). Algae, during their growth, have the capacity to assimilate nutrients and thus subsequent harvesting of the algal biomass recovers the nutrients from biowaste sources giving the possibility to transform negative environmental externalities in positive mainly in terms of eutrophication and climate change impact categories. The paper presents a novel environmental technology for the production of biogas and 2nd generation biofuel (liquid biomethane) after an upgrading process through the use of a cryogenic technology. The paper would also like to make the first attempt at understanding the possibility to implement this innovative technology in the Latvian context. The first calculations and assumptions for the Life Cycle Inventory for a further Life Cycle Assessment are presented.

Anaerobic digestion of macroalgae: methane potentials, pre-treatment, inhibition and co-digestion.

Science.gov (United States)

Nielsen, H B; Heiske, S

2011-01-01

In the present study we tested four macroalgae species--harvested in Denmark--for their suitability of bioconversion to methane. In batch experiments (53 degrees C) methane yields varied from 132 ml g volatile solids(-1) (VS) for Gracillaria vermiculophylla, 152 mi gVS(-1) for Ulva lactuca, 166 ml g VS(-1) for Chaetomorpha linum and 340 ml g VS(-1) for Saccharina latissima following 34 days of incubation. With an organic content of 21.1% (1.5-2.8 times higher than the other algae) S. latissima seems very suitable for anaerobic digestion. However, the methane yields of U. lactuca, G. vermiculophylla and C. linum could be increased with 68%, 11% and 17%, respectively, by pretreatment with maceration. U. lactuca is often observed during 'green tides' in Europe and has a high cultivation potential at Nordic conditions. Therefore, U. lactuca was selected for further investigation and co-digested with cattle manure in a lab-scale continuously stirred tank reactor. A 48% increase in methane production rate of the reactor was observed when the concentration of U. lactuca in the feedstock was 40% (VS basis). Increasing the concentration to 50% had no further effect on the methane production, which limits the application of this algae at Danish centralized biogas plant.

Large-scale bioprospecting of cyanobacteria, micro- and macroalgae from the Aegean Sea.

Science.gov (United States)

Montalvão, Sofia; Demirel, Zeliha; Devi, Prabha; Lombardi, Valter; Hongisto, Vesa; Perälä, Merja; Hattara, Johannes; Imamoglu, Esra; Tilvi, Supriya Shet; Turan, Gamze; Dalay, Meltem Conk; Tammela, Päivi

2016-05-25

Marine organisms constitute approximately one-half of the total global biodiversity, being rich reservoirs of structurally diverse biofunctional components. The potential of cyanobacteria, micro- and macroalgae as sources of antimicrobial, antitumoral, anti-inflammatory, and anticoagulant compounds has been reported extensively. Nonetheless, biological activities of marine fauna and flora of the Aegean Sea have remained poorly studied when in comparison to other areas of the Mediterranean Sea. In this study, we screened the antimicrobial, antifouling, anti-inflammatory and anticancer potential of in total 98 specimens collected from the Aegean Sea. Ethanol extract of diatom Amphora cf capitellata showed the most promising antimicrobial results against Candida albicans while the extract of diatom Nitzschia communis showed effective results against Gram-positive bacterium, S. aureus. Extracts from the red alga Laurencia papillosa and from three Cystoseira species exhibited selective antiproliferative activity against cancer cell lines and an extract from the brown alga Dilophus fasciola showed the highest anti-inflammatory activity as measured in primary microglial and astrocyte cell cultures as well as by the reduction of proinflammatory cytokines. In summary, our study demonstrates that the Aegean Sea is a rich source of species that possess interesting potential for developing industrial applications. Copyright © 2016 Elsevier B.V. All rights reserved.

PATRÓN DE DISTRIBUCIÓN DE MACROALGAS EN UN CANAL DE CORRIENTES

Directory of Open Access Journals (Sweden)

Carlos F. Candelaria Silva

2006-01-01

Full Text Available Los canales de corrientes son uno de los ambientes rocosos intermareales reconocidos en el Pacífico Tropical Mexicano. Se realizó un estudio sobre el patrón de distribución de macroalgas en un canal de corrientes en Playa Las Cuatas, Guerrero, México. Se determinaron 28 especies: 3 Chlorophyta, 9 Phaeophyta y 16 Rhodophyta. La estructura comunitaria está caracterizada por una aparente distribución en bandas definida por las especies dominantes. Una franja rosada de la coralina costrosa Lithophyllum decipiens se extiende del submareal superior hasta el intermareal medio. La feofita foliosa Sargassum liebmannii forma parches más o menos continuos en el intermareal inferior y medio. La extensión horizontal de esta especie es variable. Los niveles por arriba de L. decipiens están cubiertos por una banda extensa de feofitas costrosas. Parte del intermareal superior, medio e inferior lo ocupa Ralfsia hancockii. Mezclada con esta especie en su límite superior y extendiéndose por la zona supramareal se encuentra R. confusa. Otras especies tienen una distribución variable entremezclándose en diferentes bandas. Este patrón de distribución de especies se analiza a la luz de varias propuestas de zonación.

Screening of proteins based on macro-algae from West Java coast in Indonesian marine as a potential anti-aging agent

Science.gov (United States)

Putri, Arlina Prima; Dewi, Rizna Triana; Handayani, Aniek Sri; Harjanto, Sri; Chalid, Mochamad

2018-02-01

Algae has been known as one of the potential marine bio-resources that have been used in many fields such as bio-energy, food, pharmaceutical and medical applications. Study of macro-algae or seaweed for medicine application, in particular, highlights to empower their ingredients as a promising antioxidant like anti-aging agent due to their diversity in biological activity. The tropical climate of Indonesia with the highest marine biodiversity puts this country an auspicious source of numerous alga species as a novel antioxidant source. A Sample of 29 species of macroalgae has been collected from Coast of Pari Island as a part of Seribu Islands, Indonesia. Screening and extracting of aqueous tropical marine alga protein as a potential source for an antioxidant agent has been done by using 2,2-diphenyl-1-picrylhydrazyl scavenging method, and protein contents have been determined by Lowry method. Sample number 26 of the phylum Rhodophyta have 9.00±0.03 % protein content, which is potential for nutritional food in form of nutraceutical. That sample demonstrated the maximum DPPH scavenging activity 79.27±1.81 %. Moreover, crude extract from another species from phylum Rhodophyta had the very lower IC50 (3.4333±0.29 mg/ml) followed by Chlorophyta species (7.1069±1.78 mg/ml). In general, this study found that algae from phylum Rhodophyta possess a high content of protein, high activity towards free radical. Nevertheless, algae acquire the lowest IC50 value not only dominated by Rhodophyta but also from phylum Chlorophyta. The conclusion of this study leads to empowering high antioxidant activity algae as an anti-aging agent, which can be used in pharmaceutical applications. Therefore, the next study should be concerned on the properties of the algae which has been known to be suitable for pharmaceutical fields.

The utilization of seagrass and macroalgae substrate for settlement of sandfish Holothuria scabra larvae

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Lisa Fajar Indriana

2015-05-01

Full Text Available ABSTRACT Sandfish (Holothuria scabra is one of endangered species, which has high economical value but has not been commonly cultivated. One factor that affects the success of sandfish culture is survival of larvae during attachment phase . In this phase the larvae of H. scabra need a substrate as a place to live. This study investigated the effect of seagrass and macroalgae as the settlement substrates on the survival of H. scabra larvae. The experiment trial was conducted in UPT LPBIL LIPI Mataram using completely randomized design with five replications for each substrate treatment. The settlement substrates used were Ulva sp. (P1, Gracilaria gigas (P2, Enhalus acoroides (P3, and Eucheuma cottoni (P4. Surface area was 14x19 cm2 in each treatment. At the beginning of experiment trial, one thousand larvae were distributed into plastic tank containing 10 L seawater for each tank. After 13 days experimental period, the survival of H. scabra larvae showed significantly different among substrates treatment. The highest survival was achieved by E. acoroides (15.53±2.23%, and followed by Ulva sp. (5.07±0.74%, E. cottoni (2.57±0.25%, and G. gigas (1.96±0.17%. Keywords: settlement, Holothuria scabra, substrate, seagrass, macroalgae  ABSTRAK Teripang pasir (Holothuria scabra adalah salah satu spesies berekonomi tinggi yang terancam punah, tetapi belum banyak dibudidayakan. Salah satu faktor yang mempengaruhi tingkat keberhasilan budidaya teripang pasir adalah sintasan pada fase penempelan. Pada fase tersebut larva H. scabra memerlukan substrat sebagai tempat hidup. Penelitian ini bertujuan untuk mengevaluasi pengaruh jenis substrat lamun dan makroalga yang berbeda terhadap sintasan (STS larva teripang pasir pada fase penempelan. Penelitian dilaksanakan di Laboratorium Budidaya UPT LPBIL LIPI Mataram menggunakan metode eksperimental rancangan acak lengkap dengan lima ulangan. Perlakuan jenis substrat, yaitu: Ulva sp. (P1, Gracilaria gigas (P2

Direct hydrothermal liquefaction of undried macroalgae Enteromorpha prolifera using acid catalysts

International Nuclear Information System (INIS)

Yang, Wenchao; Li, Xianguo; Liu, Shishi; Feng, Lijuan

2014-01-01

Highlights: • Bio-oil from liquefaction of wet E. prolifera was as feasible as dry powder. • Adding acid catalysts could improve the flow property of bio-oil. • Alkenes in the bio-oil converted to ketones in the presence of acid catalysts. • Content of 5-methyl furfural increased in the bio-oil obtained with acid catalysts. • Esters were formed in the bio-oil when adding sulfuric acid as a catalyst. - Abstract: Direct liquefaction of macroalgae Enteromorpha prolifera without predrying treatment was performed in a batch reactor. Effects of temperature, reaction time, biomass-to-water ratio and acid catalysts (sulfuric acid and acetic acid) on liquefaction products were investigated. Raw material and liquefaction products were analyzed by elemental analysis, Fourier transform infrared (FT-IR) and gas chromatography–mass spectrometry (GC–MS). Results showed that liquefaction at 290 °C for 20 min with 1:3 biomass-to-water ratio produced the highest bio-oil yield of 28.4 wt%, and high heating value (HHV) was 29.5 MJ/kg. Main components of bio-oil were fatty acids, ketones, alkenes and 5-methyl furfural, and main components of water soluble organics (WSOs) were pyridines, carboxylic acids and glycerol. In the bio-oil obtained with acid catalysts, content of ketones significantly increased while alkenes disappeared. Content of 5-methyl furfural also increased. Flow property of bio-oils was improved in the presence of acid catalysts. Moreover, esters were formed when adding sulfuric acid

Effects of antifouling biocides to the germination and growth of the marine macroalga, Hormosira banksii (Turner) Desicaine

Energy Technology Data Exchange (ETDEWEB)

Myers, Jackie H. [School of Ecology and Environment, Deakin University, P.O. Box 423, Warrnambool, Victoria 3280 (Australia) and Department of Primary Industries Research Victoria, Queenscliff, P.O. Box 114 Queenscliff, Victoria 3225 (Australia) and School of Biological Sciences, Monash University, Clayton Campus, Clayton, Victoria 3800 (Australia)]. E-mail jhmyers@deakin.edu.au; Gunthorpe, Leanne [Department of Primary Industries Research Victoria, Queenscliff, P.O. Box 114 Queenscliff, Victoria 3225 (Australia)]. E-mail Leanne.Gunthorpe@dpi.vic.gov.au; Allinson, Graeme [School of Ecology and Environment, Deakin University, P.O. Box 423, Warrnambool, Victoria 3280 (Australia)]. E-mail graemea@deakin.edu.au; Duda, Susan [Department of Primary Industries Research Victoria, Queenscliff, P.O. Box 114 Queenscliff, Victoria 3225 (Australia)]. E-mail Susan.Duda@dpi.vic.gov.au

2006-09-15

The International Maritime Organisation's (IMO) ban on the use of tributyltin in antifouling paints has inevitability increased the use of old fashioned antifoulants and/or the development of new paints containing 'booster biocides'. These newer paints are intended to be environmentally less harmful, however the broader environmental effects of these 'booster biocides' are poorly known. Germination and growth inhibition tests using the marine macroalga, Hormosira banksii (Turner) Desicaine were conducted to evaluate the toxicity of four new antifouling biocides in relation to tributyltin-oxide (TBTO). Each of the biocides significantly inhibited germination and growth of Hormosira banksii spores. Toxicity was in increasing order: diuron < zineb < seanine 211 < zinc pyrithione < TBTO. However, the lack of knowledge on partitioning in the environment makes it difficult to make a full assessment on whether the four biocides tested offer an advantage over organotin paints in terms of environmental impact.

Effects of antifouling biocides to the germination and growth of the marine macroalga, Hormosira banksii (Turner) Desicaine

International Nuclear Information System (INIS)

Myers, Jackie H. . E-mail jhmyers@deakin.edu.au; Gunthorpe, Leanne . E-mail Leanne.Gunthorpe@dpi.vic.gov.au; Allinson, Graeme . E-mail graemea@deakin.edu.au; Duda, Susan . E-mail Susan.Duda@dpi.vic.gov.au

2006-01-01

The International Maritime Organisation's (IMO) ban on the use of tributyltin in antifouling paints has inevitability increased the use of old fashioned antifoulants and/or the development of new paints containing 'booster biocides'. These newer paints are intended to be environmentally less harmful, however the broader environmental effects of these 'booster biocides' are poorly known. Germination and growth inhibition tests using the marine macroalga, Hormosira banksii (Turner) Desicaine were conducted to evaluate the toxicity of four new antifouling biocides in relation to tributyltin-oxide (TBTO). Each of the biocides significantly inhibited germination and growth of Hormosira banksii spores. Toxicity was in increasing order: diuron < zineb < seanine 211 < zinc pyrithione < TBTO. However, the lack of knowledge on partitioning in the environment makes it difficult to make a full assessment on whether the four biocides tested offer an advantage over organotin paints in terms of environmental impact

Stress proteins and auxiliary anti-stress compounds in intertidal macroalgae Proteínas de estrés y compuestos anti-estrés auxiliares en algas marinas intermareales

Directory of Open Access Journals (Sweden)

Edgardo Cruces

2012-11-01

Full Text Available Intertidal macroalgae are exposed to strong variation in the physical environment and thus, diverse anti-stress mechanisms are displayed by these organisms. Stress proteins (also called heat shock proteins, HSPs have been invoked as potential protective mechanism, especially during stressful action of temperature and solar radiation. Therefore, macroalgae have not normally been used as model organisms in studies of these molecules. The present study compiles the existing information from intertidal species in the context of major factors that have been reported to induce them, e.g. temperature, enhanced solar radiation, contaminants, etc. Additionally, in order to address the question whether the expression of these proteins operates in intertidal macroalgae complementarily with other protective mechanisms, a case study of induction of HSPs after exposure to UV radiation and high temperature in two upper littoral species, Ulva sp. and Porphyra columbina, from southern Chile is presented. In parallel, two well-known responses to stress, photoinhibition of photochemical reactions (Fv/Fm and ROS scavenging were measured. The results indicated that, although stress proteins were detected in a time span between 3 and 24 h, the responses were not correlated with photochemical and antioxidative response. Overall, the study outlines a potential role of stress proteins in ecophysiological responses developed to cope mainly with high temperature and UV radiation. However, other rapid metabolic adjustments (e.g. high thermo-tolerance of photosynthesis and efficient ROS scavenging, together with other biomolecules (mycosporines, phenols, polyamines, etc. and morpho-functional adaptations to the intertidal life (e.g. small size, high area/volume ratio are also important.Las macroalgas marinas intermareales están expuestas a extrema variación en las condiciones ambientales y por ello desarrollan una serie de mecanismos anti-estrés. Las proteínas de estr

Growth and survival of Escherichia coli and enterococci populations in the macro-alga Cladophora (Chlorophyta).

Science.gov (United States)

Byappanahalli, Muruleedhara N; Shively, Dawn A; Nevers, Meredith B; Sadowsky, Michael J; Whitman, Richard L

2003-11-01

The macro-alga Cladophora glomerata is found in streams and lakes worldwide. High concentrations of Escherichia coli and enterococci have been reported in Cladophora along the Lake Michigan shore. The objective of this study was to determine if Cladophora supported growth of these indicator bacteria. Algal leachate readily supported in vitro multiplication of E. coli and enterococci, suggesting that leachates contain necessary growth-promoting substances. Growth was directly related to the concentration of algal leachate. E. coli survived for over 6 months in dried Cladophora stored at 4 degrees C; residual E. coli grew after mat rehydration, reaching a carrying capacity of 8 log CFU g(-1) in 48 h. Results of this study also show that the E. coli strains associated with Cladophora are highly related; in most instances they are genetically different from each other, suggesting that the relationship between E. coli and Cladophora may be casual. These findings indicate that Cladophora provides a suitable environment for indicator bacteria to persist for extended periods and to grow under natural conditions.

Impact of seaweed beachings on dynamics of δ(15)N isotopic signatures in marine macroalgae.

Science.gov (United States)

Lemesle, Stéphanie; Mussio, Isabelle; Rusig, Anne-Marie; Menet-Nédélec, Florence; Claquin, Pascal

2015-08-15

A fine-scale survey of δ(15)N, δ(13)C, tissue-N in seaweeds was conducted using samples from 17 sampling points at two sites (Grandcamp-Maisy (GM), Courseulles/Mer (COU)) along the French coast of the English Channel in 2012 and 2013. Partial triadic analysis was performed on the parameter data sets and revealed the functioning of three areas: one estuary (EstA) and two rocky areas (GM(∗), COU(∗)). In contrast to oceanic and anthropogenic reference points similar temporal dynamics characterized δ(15)N signatures and N contents at GM(∗) and COU(∗). Nutrient dynamics were similar: the N-concentrations in seawater originated from the River Seine and local coastal rivers while P-concentrations mainly from these local rivers. δ(15)N at GM(∗) were linked to turbidity suggesting inputs of autochthonous organic matter from large-scale summer seaweed beachings made up of a mixture of Rhodophyta, Phaeophyta and Chlorophyta species. This study highlights the coupling between seaweed beachings and nitrogen sources of intertidal macroalgae. Copyright © 2015 Elsevier Ltd. All rights reserved.

Animal diversity in Baltic rocky shore macroalgae: can Cladophora glomerata compensate for lost Fucus vesiculosus?

Science.gov (United States)

Kraufvelin, Patrik; Salovius, Sonja

2004-10-01

The substitution of canopy-forming perennial algae by annual filamentous algae is a common phenomenon on eutrophicated rocky shores with potential consequences for marine biodiversity. In the upper littoral of the northern Baltic Sea, this process is exemplified by decreased occurrence of the brown alga Fucus vesiculosus and increased amounts of filamentous algae (e.g. Cladophora glomerata and Pilayella littoralis). In this study, macrofauna communities of F. vesiculosus and C. glomerata during summer have been compared and the effects on littoral macroinvertebrates of a total or partial replacement of F. vesiculosus by C. glomerata have been estimated. The animal abundance and biomass were higher in C. glomerata than in corresponding amounts of F. vesiculosus (g dwt). Similar results were also obtained when animal abundance and biomass were extrapolated to algal cover per m 2 rocky substrate in the study area. Margalef's species richness was, on the other hand, higher in F. vesiculosus, whereas the Shannon-Wiener diversity was the same. The results indicate that C. glomerata maintains a high diversity of macroinvertebrates in the upper littoral zone of the northern Baltic Sea during summer. A possible substitution of F. vesiculosus by C. glomerata does not immediately affect macroinvertebrate diversity negatively in the littoral zone, although, it is difficult to assess the full consequences due to lack of comparable algal data at wider temporal and spatial scales.

Frações oxidáveis do carbono orgânico total e macrofauna edáfica em sistema de integração lavoura-pecuária

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Itaynara Batista

2014-06-01

Full Text Available O crescente nível de degradação das terras tem promovido a adoção de manejos agrícolas que busque aliar a produção agropecuária à conservação do solo. Entre esses, a prática da Integração Lavoura-Pecuária (ILP tem intensificado-se no Centro-Oeste brasileiro. Com o objetivo de avaliar o efeito em longo prazo do sistema ILP e da sazonalidade, sob a comunidade da macrofauna edáfica e das frações oxidáveis do carbono orgânico total (COT em áreas de cultivo e Cerradão, foi desenvolvido na Fazenda Cabeceira no município de Maracaju, MS, um estudo em que se mensurou a influência da ILP sobre as frações oxidáveis do COT e sobre a macrofauna edáfica. O sistema ILP está sendo utilizado nessa área desde 2003; o solo foi identificado como Latossolo Vermelho, localizado em área de relevo plano. As áreas amostradas possuem o seguinte histórico: soja/milho + braquiária/algodão/ aveia + pastagem/soja/formação da pastagem/pastagem; as amostragens foram realizadas na época seca, em que as culturas presentes eram pasto, milho+braquiária e algodão; e na chuvosa, com milho+braquiária, algodão e soja. Assim, as áreas nas duas épocas de avaliação foram: pasto/milho, milho+braquiária/ algodão, algodão/soja e uma área nativa de Cerradão. A amostragem foi realizada nas profundidades de 0-10, 10-20 e 20-30 cm, sendo feitas as seguintes determinações: análise da macrofauna edáfica, fracionamento granulométrico da matéria orgânica do solo (MOS e frações oxidáveis do COT. As áreas não apresentavam delineamento experimental, sendo este um estudo de observação. Os dados foram comparados pelo teste de Kruskal Wallis a 5 % e por meio da análise de redundância. A compartimentalização da MOS pode ser utilizada para a avaliação da qualidade do manejo, sendo os compartimentos mais sensíveis as frações F1 e F2 de frações oxidáveis, pois são mais lábeis no solo, já as frações F3 e F4 são as mais

Thermo-Acidic Pretreatment of Beach Macroalgae from Rügen to Optimize Biomethane Production--Double Benefit with Simultaneous Bioenergy Production and Improvement of Local Beach and Waste Management.

Science.gov (United States)

Barbot, Yann Nicolas; Thomsen, Laurenz; Benz, Roland

2015-09-03

Eutrophication is a phenomenon which can rapidly generate masses of marine macroalgae, particularly in areas with high nutrient pollution. Washed ashore, this biomass impairs coastal tourism and negatively affects the coastal ecosystem. The present study evaluates the biochemical methane potential (BMP) of a macroalgae mix (Rügen-Mix, RM (RM = Rügen-Mix)) originating from Rügen, Germany. To improve biomethane recovery, thermo-acidic pretreatment was applied to the biomass prior to biomethanation to disintegrate the biomass macrostructure. Acid hydrolysis was successfully triggered with 0.2 M industry-grade HCl at 80 °C for a 2 h period, increasing biomethane recovery by +39%, with a maximum BMP of 121 mL·g(-1) volatile solids (VS). To reduce the necessity for input material, HCl was replaced by the acidic waste product flue gas condensate (FGC). Improved performance was achieved by showing an increase in biomethane recovery of +24% and a maximum BMP of 108 mL·g(-1) VS. Continuous anaerobic digestion trials of RM were conducted for three hydraulic retention times, showing the feasibility of monodigestion. The biomethane recovery was 60 mL and 65 mL·g(-1) VS·d(-1) for thermophilic and mesophilic operation, respectively. The quality of biomethanation performance aligned to the composition of the source material which exhibited a low carbon/nitrogen ratio and an increased concentration of sulfur compounds.

Thermo-Acidic Pretreatment of Beach Macroalgae from Rügen to Optimize Biomethane Production—Double Benefit with Simultaneous Bioenergy Production and Improvement of Local Beach and Waste Management

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Yann Nicolas Barbot

2015-09-01

Full Text Available Eutrophication is a phenomenon which can rapidly generate masses of marine macroalgae, particularly in areas with high nutrient pollution. Washed ashore, this biomass impairs coastal tourism and negatively affects the coastal ecosystem. The present study evaluates the biochemical methane potential (BMP of a macroalgae mix (Rügen-Mix, RM (RM = Rügen-Mix originating from Rügen, Germany. To improve biomethane recovery, thermo-acidic pretreatment was applied to the biomass prior to biomethanation to disintegrate the biomass macrostructure. Acid hydrolysis was successfully triggered with 0.2 M industry-grade HCl at 80 °C for a 2 h period, increasing biomethane recovery by +39%, with a maximum BMP of 121 mL·g−1 volatile solids (VS. To reduce the necessity for input material, HCl was replaced by the acidic waste product flue gas condensate (FGC. Improved performance was achieved by showing an increase in biomethane recovery of +24% and a maximum BMP of 108 mL·g−1 VS. Continuous anaerobic digestion trials of RM were conducted for three hydraulic retention times, showing the feasibility of monodigestion. The biomethane recovery was 60 mL and 65 mL·g−1 VS·d−1 for thermophilic and mesophilic operation, respectively. The quality of biomethanation performance aligned to the composition of the source material which exhibited a low carbon/nitrogen ratio and an increased concentration of sulfur compounds.

Reduction of inorganics from macroalgae Laminaria digitata and spent mushroom compost (SMC) by acid leaching and selective hydrothermal liquefaction

DEFF Research Database (Denmark)

Toor, Saqib Sohail; Jasiunas, Lukas; Xu, Chunbao (Charles)

2018-01-01

Hydrothermal liquefaction (HTL) is a promising route for producing bio-crude from various biomass feedstocks. However, high content of inorganic constituents in biomass like macroalgae Laminaria digitata and spent mushroom compost (SMC) affect the conversion process and the resulting fuel products....... This research studied the effects of different acid leaching treatments on such feedstocks, subsequent HTL, and bio-crude properties. Leaching treatments were performed using five different agents: deionized water, acetic acid, citric acid, sulfuric acid, and hydrochloric acid. Performance of leaching...... was evaluated by analyzing both leached biomass and HTL products by elemental analysis, ash content, inductively coupled plasma (ICP) analysis, and X-ray diffraction (XRD) analysis. Catalytic and non-catalytic HTL of both feedstocks before and after treatment were performed in a 10-mL microreactor at 400 °C...

Impacts of harvesting methods of sugar cane on the soil macrofauna in production area in Espírito Santo – Brazil

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Eloísa dos Santos Benazzi

2013-12-01

Full Text Available The objective of this study was to evaluate the effects of harvesting methods on the macrofauna, a known indicator of soil quality that detects changes in the system and indicates management alternatives. The experimental design was randomized blocks with six replications, with each block consisting of four parcels that corresponded to treatments green cane (CC, burnt cane (CQ, green cane – burnt cane (CC-Q and burnt cane – green cane (CQ-C. Samples were collected in February and July 2010. The animals were divided into major taxonomic groups and accounted. Were evaluated ecological indexes (Shannon, Pielou and richness and average total density of individuals and groups. Data were analyzed by the nonparametric statistical tools by Friedman or Signal test at 5%. To check relationships between soil fauna and environmental variables, was used a multivariate conditional ordination method, the redundancy analysis (RDA. The index richness was more efficient than the total average density to evaluate the influence of cane harvesting systems, with the highest values related to areas harvested without burning. Further, the occurrence of key groups in the areas harvested without burning configures the establishment of a trophic web. There was dominance of the social group Formicidae in all treatments

Spread of Alsidium corallinum C. Ag. in a Tyrrhenian eutrophic lagoon dominated by opportunistic macroalgae

International Nuclear Information System (INIS)

Lenzi, Mauro; Gennaro, Paola; Renzi, Monia; Persia, Emma; Porrello, Salvatore

2012-01-01

Highlights: ► In 2007, Alsidium corallinum bloomed in Orbetello lagoon replacing other macroalgae. ► The main cause hypothesized was a transient low eutrophic level of the ecosystem. ► The results showed unusually low dissolved nitrogen in 2007. ► Dissolved N:P atomic ratio was much lower in 2007 than in the past and 2008. ► The observations suggest that the cycle of sediment OM determines vegetation cycles. - Abstract: In 2007, the Rhodophyceae Alsidium corallinum C. Ag., a marine taxon, bloomed in the eutrophic lagoon of Orbetello (Tuscany, Italy) for the first time, becoming the dominant species in spring and summer. In November, its biomass collapsed. The hypothesis examined in this study is that the bloom expressed a relatively low eutrophic level of the ecosystem after intense disposal of accumulated sedimentary organic matter (OM) by dystrophic processes in the two years preceding the bloom. To verify the hypothesis, we compared water physical–chemical variables, sediment redox (Eh) and OM, and standing crops of macroalgae and seagrass from the database of routine monitoring between 2005 and 2008. We also used dissolved nutrient data obtained in 2007 and 2008, as well as data on chlorophyll and total suspended matter in the water column during the microalgal bloom of 2007, and C, N and P content in thalli of the Chlorophycea Chaetomorpha linum and the Rhodophyceae Gracilariopsis longissima and A. corallinum obtained in 2007. In 2007, unusually low values of dissolved inorganic nitrogen (DIN) were recorded. Combined with stable values of soluble reactive phosphorus (SRPs), low DIN led to a reduction of about one order of magnitude in the DIN:SRP atomic ratio with respect to the past and to 2008. G. longissima accumulated C, N and P more than the other species and A. corallinum proved to be less demanding. Sediment OM was lower in the autumn of years characterized by dystrophy, confirming that summer dystrophic events coincided with maximum energy

Molluscs associated with the macroalgae of the genus Gracilaria (Rhodophyta): importance of algal fronds as microhabitat in a hypersaline mangrove in Northeastern Brazil.

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Queiroz, R N M; Dias, T L P

2014-08-01

The fronds of marine macroalgae play an important role in coastal ecosystems because the algae banks are utilized as a microhabitat by different taxa, including molluscs, one of the most abundant and diverse animals of marine ecosystems. In this study, we characterized the malacofauna associated with the macroalgae Gracilaria domingensis (Kützing) Sonder ex Dickie 1874 and Gracilaria cuneata Areschoug 1854 of a hypersaline mangrove on the northern coast of the state of Rio Grande do Norte, Northeastern Brazil. The first alga dominates in the rainy season and it is substituted by second one in the dry period. A total of 1,490 molluscs were surveyed, representing 56 species in 29 families: 1,081 were associated with G. domingensis and 409 with G. cuneata, the latter showing the greater diversity (H'=1.25). Columbellidae, Neritidae, Pyramidellidae and Cerithiidae were among the most representative families in the number of species and individuals. The micromolluscs were dominant in the algal microhabitat, constituting 74.63% of the malacofauna recorded. The columbellid Parvanachis obesa (C. B. Adams, 1845) was the dominant species followed by the neritid Neritina virginea (Linnaeus, 1758) in both algae. In spite of the annual alternated succession of the algae species, at least 15 mollusc species are common for these algae. Furthermore, juveniles of P. obesa were recorded in both seasons, indicating a continuous reproduction. Possible reasons for difference in abundance, diversity and dominance of molluscs living on these algae are discussed. Both species of substrate-algae represent an important microhabitat for refuge, feeding and the reproduction of small-sized mollusc species during rainy and dry seasons.

Molluscs associated with the macroalgae of the genus Gracilaria (Rhodophyta: importance of algal fronds as microhabitat in a hypersaline mangrove in Northeastern Brazil

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RNM Queiroz

Full Text Available The fronds of marine macroalgae play an important role in coastal ecosystems because the algae banks are utilized as a microhabitat by different taxa, including molluscs, one of the most abundant and diverse animals of marine ecosystems. In this study, we characterized the malacofauna associated with the macroalgae Gracilaria domingensis (Kützing Sonder ex Dickie 1874 and Gracilaria cuneata Areschoug 1854 of a hypersaline mangrove on the northern coast of the state of Rio Grande do Norte, Northeastern Brazil. The first alga dominates in the rainy season and it is substituted by second one in the dry period. A total of 1,490 molluscs were surveyed, representing 56 species in 29 families: 1,081 were associated with G. domingensis and 409 with G. cuneata, the latter showing the greater diversity (H′=1.25. Columbellidae, Neritidae, Pyramidellidae and Cerithiidae were among the most representative families in the number of species and individuals. The micromolluscs were dominant in the algal microhabitat, constituting 74.63% of the malacofauna recorded. The columbellid Parvanachis obesa(C. B. Adams, 1845 was the dominant species followed by the neritid Neritina virginea (Linnaeus, 1758 in both algae. In spite of the annual alternated succession of the algae species, at least 15 mollusc species are common for these algae. Furthermore, juveniles of P. obesa were recorded in both seasons, indicating a continuous reproduction. Possible reasons for difference in abundance, diversity and dominance of molluscs living on these algae are discussed. Both species of substrate-algae represent an important microhabitat for refuge, feeding and the reproduction of small-sized mollusc species during rainy and dry seasons.

Hydrothermal gasification of Cladophora glomerata macroalgae over its hydrochar as a catalyst for hydrogen-rich gas production.

Science.gov (United States)

Safari, Farid; Norouzi, Omid; Tavasoli, Ahmad

2016-12-01

A tubular batch micro-reactor system was used for hydrothermal gasification (HTG) of Cladophora glomerata (C. glomerata) as green macroalgae found in the southern coast of the Caspian Sea, Iran. Non-catalytic tests were performed to determine the optimum condition for hydrogen production. Hydrochar, as a solid residue of non-catalytic HTG was characterized by BET, FESEM, and ICP-OES methods to determine its physiochemical properties. Surface area and pore volume of C. glomerata increased drastically after HTG. Also, the aqueous products were identified and quantified by GC-MS and GC-FID methods. Hydrochar was loaded to the reactor to determine its catalytic effect on HTG. HTG was promoted by inorganic compounds in the hydrochar and its porosity. The maximum hydrogen yield of 9.63mmol/g was observed in the presence of algal hydrochar with the weight ratio of 0.4 to feedstock. Also, acids production was inhibited while phenol production was promoted in the presence of hydrochar. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nutrients' removal from aquaculture wastewater using the macroalgae Gracilaria birdiae

Energy Technology Data Exchange (ETDEWEB)

Marinho-Soriano, E.; Nunes, S.O.; Carneiro, M.A.A.; Pereira, D.C. [Universidade Federal do Rio Grande do Norte, Depto. de Oceanografia e Limnologia, Via Costeira, Praia de Mae Luiza, s/n, Natal, RN 59014-100 (Brazil)

2009-02-15

Intensive aquaculture releases large amount of nutrients into aquatic ecosystems and can lead to eutrophication of coastal waters. Studies conducted in aquaculture systems have demonstrated that the seaweeds are efficient in reducing nutrients and at the same time provides extra income, when species of economic importance are used. This study was conducted to evaluate whether Gracilaria birdiae could be cultivated efficiently for the production of useful algal biomass and removal of nutrients from shrimp pond effluents. The results obtained showed a gradual increase in biomass and relative growth rate (RGR) over the experimental period. Mean RGR between the weeks varied significantly (p < 0.01), reaching a maximum of 3.6 {+-} 0.35% d{sup -1} and a minimum of 1.6 {+-} 0.52% d{sup -1}. The mean for the whole period was 2.6% d{sup -1}. The biofiltration capacity of G. birdiae was confirmed by the significantly reduced concentration of the three nutrients analyzed (PO{sub 4}{sup 3-}, NH{sub 4}{sup +} and NO{sub 3}{sup -}) over the study period. The concentration of PO{sub 4}{sup 3-} decreased by 93.5%, NH{sub 4}{sup +} by 34% and NO{sub 3}{sup -} by 100% after the 4-week experimental period. The results obtained in this study indicated that G. birdiae can be used in aquaculture systems as a biofilter. In addition, the macroalgae biomass produced offers alternative source of raw material for the extraction of the phycocolloid agar, human food and animal feed. (author)

Extraction of Fucoxanthin from Raw Macroalgae excluding Drying and Cell Wall Disruption by Liquefied Dimethyl Ether

Science.gov (United States)

Kanda, Hideki; Kamo, Yuichi; Machmudah, Siti; Wahyudiono; Goto, Motonobu

2014-01-01

Macroalgae are one of potential sources for carotenoids, such as fucoxanthin, which are consumed by humans and animals. This carotenoid has been applied in both the pharmaceutical and food industries. In this study, extraction of fucoxanthin from wet brown seaweed Undaria pinnatifida (water content was 93.2%) was carried out with a simple method using liquefied dimethyl ether (DME) as an extractant in semi-continuous flow-type system. The extraction temperature and absolute pressure were 25 °C and 0.59 MPa, respectively. The liquefied DME was passed through the extractor that filled by U. pinnatifida at different time intervals. The time of experiment was only 43 min. The amount of fucoxanthin could approach to 390 μg/g dry of wet U. pinnatifida when the amount of DME used was 286 g. Compared with ethanol Soxhlet and supercritical CO2 extraction, which includes drying and cell disruption, the result was quite high. Thus, DME extraction process appears to be a good method for fucoxanthin recovery from U. pinnatifida with improved yields. PMID:24796299

Calcite encrustation in macro-algae Chara and its implication to the formation of carbonate-bound cadmium

International Nuclear Information System (INIS)

Siong, Kian; Asaeda, Takashi

2009-01-01

We studied the relationship between macro-algae Chara (Stoneworts) calcite (CaCO 3 ) encrustation and the speciation of cadmium (Cd) accumulated by the plant. Results showed that 17% of the total Cd (0.3 mg kg -1 ) accumulated by Chara fibrosa exposed to 1 μg Cd L -1 was carbonate-bound. The percentage of carbonate-bound Cd in the plant exposed to 10 μg Cd L -1 increased from 48% in young thalli (total Ca -1 , total Cd: 125 mg kg -1 ) to 63% in calcified mature thalli (total Ca: 190 mg g -1 ; total Cd: 134 mg kg -1 ). Based on mineral saturation calculation and reliability analysis of the sequential fractionation procedure, precipitation of otavite (CdCO 3 ) and co-precipitation of Cd with calcite, occurring in the alkaline regions of Chara cell wall, are probably the mechanisms of carbonate-bound Cd formation. Thick marl sediment frequently found beneath charophyte meadows suggests a long-term storage of Ca as well as the precipitated or co-precipitated Cd in the sediment after the plant senescence and decomposition.

Synthesis of the state of knowledge about species richness of macroalgae, macroinvertebrates and fishes in coastal and oceanic waters of Easter and Salas y Gómez islands

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Miriam Fernández

2014-10-01

Full Text Available From the beginning of the 19th century on, several small sampling trips as well as large national and international scientific expeditions have been carried out to Easter Island (EI and Salas y Gómez Island (SGI. The objective of this study is to compile, synthesize and analyze published information about the biodiversity of macroalgae, macroinvertebrates and fishes associated with EI-SGI, updating the state of knowledge and making it available for the development of conservation plans. We searched all the available sources of information, such as scientific publications, scientific expeditions, fisheries data, technical reports, books, databases and online sources. We found 964 species reported within EI-SGI (143 species of macroalgae, 605 macroinvertebrates and 216 fishes, the majority for EI (923; for SGI 171 species have been reported. Species richness has increased over time, without leveling off, as sampling effort increases. However, seamounts and hydrothermal vents have been poorly studied in Chile's Exclusive Economic Zone (EEZ. A high percentage of endemism has been determined for the majority of the taxonomic groups, with mollusks and poriferans exhibiting the highest levels of endemism (33 -34%. Thus, the Rapanuian biogeographic province can be clearly identified, but information to differentiate between EI and SGI, and direct island-specific conservation efforts, is lacking. Nevertheless, the most vulnerable yet unprotected habitats (hydrothermal vents, higher diversity of seamounts size are located towards the western limit of the EEZ.

Proximate Composition and Nutritional Value of Three Macroalgae: Ascophyllum nodosum, Fucus vesiculosus and Bifurcaria bifurcata

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José M. Lorenzo

2017-11-01

Full Text Available Proximate composition (moisture, protein, lipid and ash content and nutritional value (fatty acid, amino acid and mineral profile of three macroalgae (Ascophyllum nodosum, Fucus vesiculosus and Bifurcaria bifurcate were studied. Chemical composition was significantly (p < 0.001 different among the three seaweeds. In this regard, the B. bifurcata presented the highest fat content (6.54% of dry matter; whereas, F. vesiculosus showed the highest protein level (12.99% dry matter. Regarding fatty acid content, the polyunsaturated fatty acids (PUFAs were the most abundant followed by saturated fatty acids (SFAs and monounsaturated fatty acids (MUFAs. On the other hand, the three seaweeds are a rich source of K (from 3781.35 to 9316.28 mg/100 g, Mn (from 8.28 to 1.96 mg/100 g, Na (from 1836.82 to 4575.71 mg/100 g and Ca (from 984.73 to 1160.27 mg/100 g. Finally, the most abundant amino acid was glutamic acid (1874.47–1504.53 mg/100 dry matter, followed by aspartic acid (1677.01–800.84 mg/100 g dry matter and alanine (985.40–655.73 mg/100 g dry matter.

Conventional and microwave pyrolysis of a macroalgae waste from the Agar-Agar industry. Prospects for bio-fuel production.

Science.gov (United States)

Ferrera-Lorenzo, N; Fuente, E; Bermúdez, J M; Suárez-Ruiz, I; Ruiz, B

2014-01-01

A comparative study of the pyrolysis of a macroalgae industrial solid waste (algae meal) in an electrical conventional furnace and in a microwave furnace has been carried out. It was found that the chars obtained from both pyrolyses are similar and show good properties for performing as a solid bio-fuel and as a precursor of activated carbon. Bio-oils from conventional pyrolysis have a greater number of phenolic, pyrrole and alkane compounds whereas benzene and pyridine compounds are more predominant in microwave pyrolysis with a major presence of light compounds. The bio-gas fraction from microwave pyrolysis presents a much higher syngas content (H2+CO), and a lower CO2 and CH4 proportion than that obtained by conventional pyrolysis. Yields are similar for both treatments with a slightly higher gas yield in the case of microwave pyrolysis due to the fact that microwave heating favors heterogeneous reactions between the gases and the char. Copyright © 2013 Elsevier Ltd. All rights reserved.

High mortality of Zostera marina under high temperature regimes but minor effects of the invasive macroalgae Gracilaria vermiculophylla

DEFF Research Database (Denmark)

Höffle, Hannes; Thomsen, M.S.; Holmer, M.

2011-01-01

The present study tested for density-dependent effects of the invasive drift macroalgae Gracilaria vermiculophylla (Ohmi) Papenfuss on growth and survival of the native eelgrass, Zostera marina L., under different temperature levels. Three weeks laboratory experiments were conducted in Odense......, Denmark, combining three algae densities (control, low 1.9 kg WW m2, high 4.5 kg WW m2) with typical Danish summer temperatures (18 C) and elevated temperatures (21 C and 27 C). There was a significant effect of temperature on shoot survival with on average 68% mortality in the high temperature treatment...... but almost no mortality at the two lower temperatures. The higher mortality was probably caused by high sulphide levels in the sediment pore water (0.6 mmol l1 at 18 C compared to 3.7 mmol l1 at 27 C). Above-ground growth of the surviving shoots was also significantly affected by temperature, with leaf...

Natural and Fukushima-derived radioactivity in macroalgae and mussels along the Japanese shoreline

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Z. Baumann

2013-06-01

Full Text Available Following the failure of the nuclear power plant in Fukushima Prefecture in March 2011, peer-reviewed publications describing radioactivity levels in organisms inhabiting coastal environments are scarce. This paper reports on elevated levels of 134Cs and 137Cs in macroalgae and mussels (up to ~ 800 Bq kg−1 dry wt. in June 2011. Cs concentrations in biota sampled in early June 2011 were higher in areas south of Fukushima than sampled in the last third of the month north of Fukushima. Activity concentrations from 134+137Cs in organisms south of Fukushima were comparable to or lower than those from the naturally occurring 40K in the same samples. While 210Pb and 210Po concentrations were generally lower than these other radionuclides, 210Po as an α-emitter is more significant from a radiological viewpoint than γ-emitters as it can inflict greater biological damage. By applying known bioconcentration factors of Cs in biota, measured biota concentrations of Cs were also used to estimate Cs concentrations in coastal seawater to be in the range of 102–103 Bq m−3. These estimates show that, 3 months after the accident and maximal release of radioactive Cs, levels of Cs persisted in coastal waters, although at levels that were two orders of magnitude lower than at the time of release. These June coastal seawater Cs levels were four orders of magnitude above Cs concentrations off Japan prior to the Fukushima disaster.

La macrofaune du sol améliore l'efficience de l'utilisation de l ...

African Journals Online (AJOL)

... semi-arid zone of Burkina Faso on lixisol to evaluate the impact of soil macrofauna and ... The main plots are the plots with soil macrofauna and the plots without soil macrofauna. The secondary plots consist of four (04)-soil fertility management and one ... On the other hand, it had no significant effect on microbial biomass.

Can macroalgae provide promising anti-tumoral compounds? A closer look at Cystoseira tamariscifolia as a source for antioxidant and anti-hepatocarcinoma compounds

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Catarina Vizetto-Duarte

2016-02-01

Full Text Available Marine organisms are a prolific source of drug leads in a variety of therapeutic areas. In the last few years, biomedical, pharmaceutical and nutraceutical industries have shown growing interest in novel compounds from marine organisms, including macroalgae. Cystoseira is a genus of Phaeophyceae (Fucales macroalgae known to contain bioactive compounds. Organic extracts (hexane, diethyl ether, ethyl acetate and methanol extracts from three Cystoseira species (C. humilis, C. tamariscifolia and C. usneoides were evaluated for their total phenolic content, radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS radicals, and antiproliferative activity against a human hepatocarcinoma cell line (HepG2 cells. C. tamariscifolia had the highest TPC and RSA. The hexane extract of C. tamariscifolia (CTH had the highest cytotoxic activity (IC50 = 2.31 µg/mL, and was further tested in four human tumor (cervical adenocarcinoma HeLa; gastric adenocarcinoma AGS; colorectal adenocarcinoma HCT-15; neuroblastoma SH-SY5Y, and two non-tumor (murine bone marrow stroma S17 and human umbilical vein endothelial HUVEC cell lines in order to determine its selectivity. CTH strongly reduced viability of all tumor cell lines, especially of HepG2 cells. Cytotoxicity was particularly selective for the latter cells with a selectivity index = 12.6 as compared to non-tumor cells. Incubation with CTH led to a 2-fold decrease of HepG2 cell proliferation as shown by the bromodeoxyuridine (BrdU incorporation assay. CTH-treated HepG2 cells presented also pro-apoptotic features, such as increased Annexin V/propidium iodide (PI binding and dose-dependent morphological alterations in DAPI-stained cells. Moreover, it had a noticeable disaggregating effect on 3D multicellular tumor spheroids. Demethoxy cystoketal chromane, a derivative of the meroditerpenoid cystoketal, was identified as the active compound

Optimization of enzymatic saccharification of Chaetomorpha linum biomass for the production of macroalgae-based third generation bioethanol

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Ahmed Slaheddine Masmoudi

2016-08-01

Full Text Available To evaluate the efficacy of marine macro-algae Chaetomorpha linum as a potential biofuel resource, the effects of the enzymatic treatment conditions on sugar yield were evaluated using a three factor three level Box-Behnken design. The hydrothermally pretreated C. linum biomass was treated with Aspergillus niger cellulase at various liquid to solid ratios (50–100 mL/g, enzyme concentrations (10–60 U/g and incubations times (4–44 h. Data obtained from the response surface methodology were subjected to the analysis of variance and analyzed using a second order polynomial equation. The fitted model was found to be robust and was used to optimize the sugar yield (% during enzymatic hydrolysis. The optimum saccharification conditions were: L/S ratio 100 mL/g; enzyme concentration 52 U/g; and time 44 h. Their application led to a maximum sugar yield of 30.2 g/100g dry matter. Saccharomyces cerevisiae fermentation of the algal hydrolysate provided 8.6 g ethanol/100g dry matter. These results showed a promising future of applying C. linum biomass as potential feedstock for third generation bioethanol production.

Actividad antibacteriana de extractos etanólicos de macroalgas marinas de la costa central del Perú

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Claudio Magallanes

2013-06-01

Full Text Available Se evaluó la actividad antibacteriana de extractos etanólicos de 12 especies de macroalgas marinas. Los extractos fueron obtenidos de acuerdo al protocolo modificado de Vlachos et al. (1996. Cada extracto se enfrentó contra 5 cepas bacterianas de origen clínico y 6 no clínico perteneciente a los géneros Staphylococcus, Enterococcus, Pseudomonas, Escherichia, Salmonella, Aeromonas y Vibrio. De 12 especies de algas ensayadas solamente 5 (Grateloupia doryphora, Ahnfeltiopsis durvillaei, Prionitis decipiens, Petalonia fascia y Bryopsis plumosa presentaron algún efecto antibacteriano. Asimismo, de 11 cepas bacterianas probadas solamente las cepas clínicas Staphylococcus aureus ATCC 25923 y Enterococcus faecalis ATCC 29212 y la cepa no clínica Staphylococcus aureus ATCC 6633 fueron sensibles a los extractos algales. El extracto etanólico de B. plumosa presentó el mayor efecto antibacteriano contra las dos cepas de S. aureus, manifestándose en el mayor tamaño de sus halos de inhibición, mientras que el extracto de P. fascia mostró mayor espectro antibacteriano, inhibiendo a las 3 cepas mencionadas.

Evaluation the impact of habitat quality on the soil fauna in Jajarm region

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G.A. Rassam

2016-04-01

Full Text Available The effects of land use, crop type and crop management on soil fauna were investigated with survey of four habitats in Jajarm. The habitats included rangelands, alfalfa (Medicago sativa L. fields and low-input and high-input of wheat (Triticum aestivum L. fields, each with four sample units. In each sample unit, the macrofauna collected with pitfall traps, sorted and counted in terms of family. The analysis of data conducted using of contrast analysis, analysis of similarities and principal component analysis (PCA. In rangelands the taxonomic richness, Simpson diversity index and abundance of macrofauna families tremendously were lower than agricultural habitats. These were attributed to low of plant diversity and pressure of livestock grazing. In alfalfa fields, increased abundance of beneficial macrofauna than wheat fields due to use not of chemical inputs, low disturbance and perennial of alfalfa. The crop management dad not has any significant impact on soil macrofauna. However, soil important macrofauna showed great tendency to occupancy in low-input wheat fields.

An evaluation of the toxicity and bioaccumulation of thallium in the coastal marine environment using the macroalga, Ulva lactuca.

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Turner, Andrew; Furniss, Oliver

2012-12-01

Thallium(I) has been added to cultures of the marine macroalga, Ulva lactuca, for a period of 48 h and the accumulation of the metal and its effects on the photochemical efficiency of photosystem II (PS II) measured. Thallium elicited a measurable toxic response above concentrations of 10 μg L⁻¹ in both coastal seawater (salinity 33) and estuarine water (salinity 20). The accumulation of Tl was defined by a linear relationship with aqueous Tl and accumulation factors of about 900 mL g⁻¹ in both media. Thallium accumulated by U. lactuca that was resistant to an EDTA extraction and, by operational definition, internalised, exceeded 90% in both cases. Accumulation and toxicity of Tl in the presence of a ∼10⁵-fold excess of its biogeochemical analogue, potassium, suggests that Tl has a high intrinsic phytotoxicity and that its mode of action involves permeation of the cell membrane as Tl⁺ through NaCl-KCl co-transporter sites rather than (or in addition to) transport through K⁺ ion channels. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mechano-Enzymatic Deconstruction with a New Enzymatic Cocktail to Enhance Enzymatic Hydrolysis and Bioethanol Fermentation of Two Macroalgae Species

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Sameh Amamou

2018-01-01

Full Text Available The aim of this study was to explore the efficiency of a mechano-enzymatic deconstruction of two macroalgae species for sugars and bioethanol production, by using a new enzymatic cocktail (Haliatase and two types of milling modes (vibro-ball: VBM and centrifugal milling: CM. By increasing the enzymatic concentration from 3.4 to 30 g/L, the total sugars released after 72 h of hydrolysis increased (from 6.7 to 13.1 g/100 g TS and from 7.95 to 10.8 g/100 g TS for the green algae U. lactuca and the red algae G. sesquipedale, respectively. Conversely, total sugars released from G. sesquipedale increased (up to 126% and 129% after VBM and CM, respectively. The best bioethanol yield (6 geth/100 g TS was reached after 72 h of fermentation of U. lactuca and no increase was obtained after centrifugal milling. The latter led to an enhancement of the ethanol yield of G. sesquipedale (from 2 to 4 g/100 g TS.

Diversidad y distinción taxonómica de la macrofauna en fondos blandos de la plataforma norte y suroccidental cubana

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Gema Hidalgo

2015-11-01

Full Text Available Se evaluó la diversidad de la macrofauna en fondos blandos de la plataforma marina cubana norte y suroccidental. Se utilizaron índices de variación taxonómica que aportan una nueva dimensión en la interpretación de la diversidad de las comunidades, que son independientes del tipo de hábitat y del esfuerzo de muestreo, y tienen respuesta monotónica ante las perturbaciones del ambiente. La heterogeneidad de taxones fue significativamente mayor en los biotopos areno-fangoso con vegetación, arenoso con vegetación y arenoso con vegetación sobre fondo duro. La diversidad por biotopos reflejó un gradiente de menor a mayor tamaño de partícula y de ausencia a presencia de vegetación. La distinción taxonómica promedio (Δ+ esperada en estas zonas de la plataforma cubana es de 92,5, con límites de confianza de 95% entre 76,7 y 100. Las estaciones con distinción taxonómica promedio <92,5 y fuera del límite de confianza inferior, se pueden considerar con condiciones ambientales de deterioro o que favorecen la diversidad de algún grupo en particular. Los grupos dominantes en esta fracción del bentos son crustáceos y poliquetos, como ocurre en otras regiones tropicales y templadas. Estos resultados sirven de base para la evaluación y monitoreo ambiental del macrozoobentos como componente clave del funcionamiento de ecosistemas marinos en fondos blandos de Cuba.

Macroalgas bentônicas associadas a bancos de Hypnea musciformis (Wulfen J.V. Lamour. (Rhodophyta - Gigartinales em duas praias do litoral baiano Macroalgae associated with banks of Hypnea musciformis (Wulfen J.V. Lamour. (Rhodophyta, Gigartinales on two beaches on the coast of Bahia

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Iara Oliveira Costa

2012-06-01

Full Text Available Este trabalho caracteriza a estrutura e dinâmica das comunidades de macroalgas bentônicas associadas a populações de H. musciformis ocorrentes em formações recifais nas praias de Stella Maris (Salvador e Itacimirim (Camaçari. As coletas ocorreram entre agosto de 2007 e junho de 2008. As formações recifais foram divididas em compartimentos com base no hidrodinamismo. Utilizou-se três transectos em cada compartimento, onde foram dispostos cinco quadrados de 20 x 20 cm. Foram obtidos dados de riqueza, biomassa, percentual de importância (Pi%, diversidade (H' e equitabilidade (J'. Na área estudada ocorreram 60 espécies: 30 Rhodophyta, 20 Chlorophyta e 10 Ochrophyta; biomassa média de 136 g.m-² (peso seco; e índices médios de H' e J' de 2,7 e 0,97, respectivamente. Houve predominância das rodofíceas, tanto em riqueza específica quanto em valores de biomassa. Foi encontrada maior contribuição do grupo morfo-funcional de algas corticadas. Dentre a flora associada, Gelidiella acerosa, Sargassum cymosum e Palisada perforata apresentaram maiores valores de biomassa. O compartimento recifal mais representativo em riqueza específica e biomassa foi a região frontal do recife. As comunidades das praias estudadas foram consideradas distintas devido à fisionomia das formações recifais.This study characterized the structure and dynamics of macroalgae communities associated with benthic populations of H. musciformis occurring in reef formations on the beaches of Stella Maris (Salvador and Itacimirim (Camaçari, Bahia. The samples were collected between August 2007 and June 2008. The reef formations were divided into compartments based on hydrodynamics. Three transects where made for each compartment, and each of these had five quadrants of 20 x 20cm. Data about the richness, biomass, percentage of importance (Pi%, diversity (H' and evenness (J' was collected. The study recorded 60 species, 30 Rhodophyta, 20 Chlorophyta and 10 Ochrophyta

Spatial distribution of microphytobenthos, meiofauna and macrofauna in the north-western Adriatic Sea: a synoptic study

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Annalisa Franzo

2015-12-01

Full Text Available In view of the general paucity of integrated information on offshore benthic communities in the Adriatic Sea and given the vulnerability of this particular coastal system, microphytobenthos, meiofauna and macrofauna were synoptically investigated in front of the Emilia-Romagna coast (northern Adriatic Sea in September 2010 and March 2011. As required by the Marine Strategy Framework Directive, which extends its action beyond the territorial waters (within 12 nmi of the Member States, our findings could help to fill the gap of knowledge on the environmental status in offshore areas since the study was carried out also at >12 nmi from the coastline. In fact, sediment samples for the analysis of the benthic communities were collected from a 10-point-station grid that covered an area of about 400 km2 with water depths ranging from 13 to 50 m. The variability of the sediment grain size and other chemical variables in the sediment suggests the presence of two distinct environmental contexts that enhance the proliferation of different benthic communities. At the inshore stations (depth <20 m the higher sand percentages and the maxima of dissolved inorganic nitrogen concentrations indicate the presence of hydrodynamic perturbations and the influence of nutrient loads of terrestrial origin. Inshore, both meio- and macrofaunal communities were poorly structured and dominated by relatively more opportunistic taxa, such as nematodes and the bivalve Corbula gibba. Offshore stations (depth >20 m had muddier sediments, which likely exerted a greater retention of sediment-bound organic matter. These conditions seemed to favour benthic deposit feeders like meio- and macrofaunal annelids. Surprisingly, a conspicuous microphytobenthic community, mainly represented by the diatom Paralia sulcata, has been observed even at remarkable depths (~50 m opening new questions regarding the role of these organisms in dim-light conditions. Although the investigated benthic

Benthos

Digital Repository Service at National Institute of Oceanography (India)

Ansari, Z.A.; Parulekar, A.H.

Benthic organisms are sessile and sedentary in nature. True benthos can be divided into two groups - epifauna and infauna. They comprise major invertebrate phyla. Benthic organisms are separated into micro, meio, macro and mega-benthos based on size...

Exploring bacteria-induced growth and morphogenesis in the green macroalga order Ulvales (Chlorophyta

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Thomas eWichard

2015-03-01

Full Text Available Green macroalgae, such as Ulvales, lose their typical morphology completely when grown under axenic conditions or in the absence of the appropriate microbiome. As a result, slow growing aberrant phenotypes or even callus-like morphotypes are observed in Ulvales. The cross-kingdom interactions between marine algae and microorganisms are hence not only restricted by the exchange of macronutrients, including vitamins and nutrients, but also by infochemicals such as bacterial morphogenetic compounds. The latter are a fundamental trait mediating the mutualism within the chemosphere where the organisms interact with each other via compounds in their surroundings.Approximately 60 years ago, pilot studies demonstrated that certain bacteria promote growth, whereas other bacteria induce morphogenesis; this is particularly true for the order of Ulvales. However, only slow progress was made towards the underlying mechanism due to the complexity of, for example, algal cultivation techniques, and the lack of standardized experiments in the laboratory.A breakthrough in this research was the discovery of the morphogenetic compound thallusin, which was isolated from an epiphytic bacterium and induces normal germination and restores the foliaceous morphotypes of Monostroma. Owing to the low concentration, the purification and structure elucidation of highly biologically active morphogenetic compounds is still challenging. Recently, it was found that only the combination of two specific bacteria from the Rhodobacteraceae and Flavobacteriaceae can completely recover the growth and morphogenesis of axenic Ulva mutabilis cultures forming a symbiotic tripartite community by chemical communication.This review combines literature detailing evidence of bacteria-induced morphogenesis in Ulvales. A set of standardized experimental approaches is further proposed for the preparation of axenic algal tissues, bacteria isolation, co-cultivation experiments, and the analysis of

Effects of herbivore exclusion and nutrient enrichment on coral reef macroalgae and cyanobacteria

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Thacker, R.; Ginsburg, D.; Paul, V.

2001-05-01

Although phase shifts on coral reefs from coral-dominated to algal-dominated communities have been attributed to the effects of increased nutrient availability due to eutrophication and reduced herbivore abundance due to overfishing and disease, these factors have rarely been manipulated simultaneously. In addition, few studies have considered the effects of these factors on benthic, filamentous cyanobacteria (blue-green algae) as well as macroalgae. We used a combination of herbivore-exclusion cages and nutrient enrichment to manipulate herbivore abundance and nutrient availability, and measured the impacts of these treatments on macroalgal and cyanobacterial community structure. In the absence of cages, surface cover of the cyanobacterium Tolypothrix sp. decreased, while surface cover of the cyanobacteria Oscillatoria spp. increased. Cyanobacterial cover decreased in partial cages, and Tolypothrix sp. cover decreased further in full cages. Lower cyanobacterial cover and biomass were correlated with higher macroalgal cover and biomass. Dictyota bartayresiana dominated the partial cages, while Padina tenuis and Tolypiocladia glomerulata recruited into the full cages. Palatability assays demonstrated that herbivore-exclusion shifted macroalgal species composition from relatively unpalatable to relatively palatable species. Nutrient enrichment interacted with herbivore exclusion to increase the change in cover of D. bartayresiana in the uncaged and fully caged plots, but did not affect the final biomass of D. bartayresiana among treatments. Nutrient enrichment did not significantly affect the cover or biomass of any other taxa. These results stress the critical role of herbivory in determining coral reef community structure and suggest that the relative palatabilities of dominant algae, as well as algal growth responses to nutrient enrichment, will determine the potential for phase shifts to algal-dominated communities.

Exploring bacteria-induced growth and morphogenesis in the green macroalga order Ulvales (Chlorophyta)

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Wichard, Thomas

2015-01-01

Green macroalgae, such as Ulvales, lose their typical morphology completely when grown under axenic conditions or in the absence of the appropriate microbiome. As a result, slow growing aberrant phenotypes or even callus-like morphotypes are observed in Ulvales. The cross-kingdom interactions between marine algae and microorganisms are hence not only restricted by the exchange of macronutrients, including vitamins and nutrients, but also by infochemicals such as bacterial morphogenetic compounds. The latter are a fundamental trait mediating the mutualism within the chemosphere where the organisms interact with each other via compounds in their surroundings. Approximately 60 years ago, pilot studies demonstrated that certain bacteria promote growth, whereas other bacteria induce morphogenesis; this is particularly true for the order of Ulvales. However, only slow progress was made towards the underlying mechanism due to the complexity of, for example, algal cultivation techniques, and the lack of standardized experiments in the laboratory. A breakthrough in this research was the discovery of the morphogenetic compound thallusin, which was isolated from an epiphytic bacterium and induces normal germination restoring the foliaceous morphotypes of Monostroma. Owing to the low concentration, the purification and structure elucidation of highly biologically active morphogenetic compounds are still challenging. Recently, it was found that only the combination of two specific bacteria from the Rhodobacteraceae and Flavobacteriaceae can completely recover the growth and morphogenesis of axenic Ulva mutabilis cultures forming a symbiotic tripartite community by chemical communication. This review combines literature detailing evidences of bacteria-induced morphogenesis in Ulvales. A set of standardized experimental approaches is further proposed for the preparation of axenic algal tissues, bacteria isolation, co-cultivation experiments, and the analysis of the chemosphere

Potential reversal of a phase shift: the rapid decrease in the cover of the invasive green macroalga Dictyosphaeria cavernosa Forsskål on coral reefs in Kāne`ohe Bay, Oahu, Hawai`i

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Stimson, J.; Conklin, E.

2008-12-01

The native green macroalga Dictyosphaeria cavernosa dominated most of the reef slope habitat in Kāne‘ohe Bay, Hawai‘i for 40 years prior to 2006 and had displaced corals from the habitats they created. This has been one of the most oft-cited examples of a phase shift occurring on a coral reef. After decades of relatively constant, high abundance of the alga, percent cover declined dramatically throughout the bay between February and June 2006. The sudden decrease in cover of this alga appears to be the result of an unusually protracted cloudy, rainy period in March 2006, which may have reduced irradiance and caused the alga to lose weight. Corals and red macroalgae living at the same depths and in some of the same habitats were apparently not affected by this 42-day period of rain and overcast skies. Competition between corals and D. cavernosa for space on reef slopes has been virtually eliminated by the death of this alga, but the unstable rubble formations, which remain in much of the area formerly covered by D. cavernosa may not be conducive to rapid increase in cover by the remaining corals or to establishment by coral recruits. Two years later, there was still no recovery of D. cavernosa. This represents a rare example of decline in macroalgal dominance on a reef and a partial reversal, possibly only temporary, of a phase shift.

Macrofauna of shallow hydrothermal vents on the Arctic Mid-Ocean Ridge at 71N

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Schander, C.; Rapp, H. T.; Pedersen, R. B.

2007-12-01

Deep-sea hydrothermal vents are usually associated with a highly specialized fauna and since their discovery in 1977, more than 400 species of animals have been described. Specialized vent fauna includes various animal phyla, but the most conspicuous and well known are annelids, mollusks and crustaceans. We have investigated the fauna collected around newly discovered hydrothermal vents on the Mohns Ridge north of Jan Mayen. The venting fields are located at 71°N and the venting takes place within two main areas separated by 5 km. The shallowest vent area is at 500-550 m water depth and is located at the base of a normal fault. This vent field stretches approximately 1 km along the strike of the fault, and it is composed of 10-20 major vent sites each with multiple chimney constructions discharging up to 260°C hot fluids. A large area of diffuse, low- temperature venting occurs in the area surrounding the high-temperature field. Here, partly microbial mediated iron-oxide-hydroxide deposits are abundant. The hydrothermal vent sites do not show any high abundance of specialized hydrothermal vent fauna. Single groups (i.e. Porifera and Mollusca) have a few representatives but groups otherwise common in hydrothermal vent areas (e.g. vestimentifera, Alvinellid worms, mussels, clams, galathaeid and brachyuran crabs) are absent. Up until now slightly more than 200 species have been identified from the vent area. The macrofauna found in the vent area is, with few exceptions, an assortment of bathyal species known in the area. One endemic, yet undescribed, species of mollusc has been found so far, an gastropod related to Alvania incognita Warén, 1996 and A. angularis Warén, 1996 (Rissoidae), two species originally described from pieces of sunken wood north and south of Iceland. It is by far the most numerous mollusc species at the vents and was found on smokers, in the bacterial mats, and on the ferric deposits. A single specimen of an undescribed tanaidacean has also

Cesium-137 concentrations in marine macroalgae from different biotopes in the Aegean Sea (Greece).

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Sawidis, Thomas; Heinrich, Gerorg; Brown, Murray-T

2003-03-01

The commonest species of red, brown, and green macroalgae were sampled from a range of biotopes in the Aegean Sea during 1998 for their 137Cs content. Significant differences in 137Cs concentrations were found among different species growing under similar environmental conditions, suggesting that uptake does not follow physical levels but is influenced by allometric parameters and physiological mechanisms. 137Cs content in collected seaweeds were in the descending order: Ulva lactuca>Enteromorpha linza>Gracilaria verrucosa>Ceramium rubrum>Cystoseira barbata. A comparison of the stations studied indicated that the degree of accumulation is also dependent on the geomorphology of the specific area. The west side of Thermaikos Gulf, where the rivers Axios, Aliakmon, and Pinios flow, was highly contaminated as was the Strymonicos Gulf where the river Strymon flows. High cesium concentrations were also observed in algae from Lemnos Island near the mouth of the Dardanelles Channel, most likely due to the horizontal circulation of water masses from the Marmaras Sea to the Aegean Sea resulting in the discharge of 137Cs during the purification process in the Black Sea through the Dardanelles Straits. It is concluded that the general dispersion of 137Cs results from the water circulation regime within the Aegean Sea. Higher levels are present in the northern part of the basin due to current circulation originating from the Black Sea and from outflow of rivers. Levels decrease to the south and east, but increase again to the west of Crete where the Black Sea water mass can be periodically traced.

Inhibition of photosynthesis in the microalga Chaetoceros curvisetus (Bacillariophyta) by macroalga Gracilaria lemaneiformis (Rhodophyta)

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Ye, Changpeng; Zhang, Mengcheng; Yang, Yufeng

2013-11-01

We investigated the effects of dried macroalga Gracilaria lemaneiformis (Rhodophyta) on photosynthesis of the bloom-forming microalga Chaetoceros curvisetus. C. curvisetus was cultured with different amounts of dried G. lemaneiformis under controlled laboratory conditions. We measured the photosynthetic oxygen evolution rate and established the chlorophyll a fluorescence transient (OJIP) curve coupled with its specific parameters. We observed concentration-dependent and time-dependent relationships between dried G. lemaneiformis and inhibition of photosynthesis in C. curvisetus. Co-culture with dried G. lemaneiformis also resulted in a decrease in the light-saturated maximum photosynthetic oxygen evolution rate ( P max) in C. curvisetus, and a decrease in the OJIP curve along with its specific parameters; the maximum photochemical efficiency of PSII ( F v / F m), the amount of active PSII reaction centers per excited cross section at t=0 and t= t FM (RC/CS0 and RC/CSm, respectively), the absorption flux per excited cross section at t =0 (ABS/ CS0), and the efficiency with which a trapped exciton moves an electron into the electron transport chain ( ψ 0). The dark respiration rate ( R d) increased in C. curvisetus co-cultured with dried G. lemaneiformis. The JIP-test and the oxygen evolution results indicated that dried G. lemaneiformis decreased the number of active reaction centers, blocked the electron transport chain, and damaged the oxygen-evolving complex of C. curvisetus. This result indicated that dried fragments of G. lemaneiformis could effectively inhibit photosynthesis of C. curvisetus, and thus, could serve as a functional product to control and mitigate C. curvisetus blooms.

Desiccation induces accumulations of antheraxanthin and zeaxanthin in intertidal macro-alga Ulva pertusa (Chlorophyta.

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Xiujun Xie

Full Text Available For plants and algae, exposure to high light levels is deleterious to their photosynthetic machineries. It also can accelerate water evaporation and thus potentially lead to drought stress. Most photosynthetic organisms protect themselves against high light caused photodamages by xanthophyll cycle-dependent thermal energy dissipation. It is generally accepted that high light activates xanthophyll cycle. However, the relationship between xanthophyll cycle and drought stress remains ambiguous. Herein, Ulva pertusa (Chlorophyta, a representative perennial intertidal macro-algae species with high drought-tolerant capabilities and simple structures, was used to investigate the operation of xanthophyll cycle during desiccation in air. The results indicate that desiccation under dim light induced accumulation of antheraxanthin (Ax and zeaxanthin (Zx at the expense of violaxanthin (Vx. This accumulation could be arrested by dithiothreitol completely and by uncoupler (carbonyl cyanide p-trifluoromethoxyphenylhydrazone partially, implying the participation of Vx de-epoxidase in conversion of Vx to Ax and Zx. Treatment with inhibitors of electron transport along thylakoid membrane, e.g. DCMU, PG and DBMIB, did not significantly arrest desiccation-induced accumulation of Ax and Zx. We propose that for U. pertusa, besides excess light, desiccation itself could also induce accumulation of Ax and Zx. This accumulation could proceed without electron transport along thylakoid membrane, and is possibly resulting from the reduction of thylakoid lumen volume during desiccation. Considering the pleiotropic effects of Ax and Zx, accumulated Ax and Zx may function in protecting thylakoid membrane and enhancing thermal quenching during emersion in air.

Effects of solar UV radiation on photosynthesis and enzyme activities (carbonic anhydrase and nitrate reductase in marine macroalgae from southern Spain Efectos de la radiación solar UV sobre la fotosíntesis y actividades enzimáticas (anhidrasa carbónica y nitrato reductasa en macralgas marinas del sur de España

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FÉLIX L. FIGUEROA

2001-06-01

Full Text Available The effects of solar ultraviolet (UV radiation during daily cycles on photosynthesis and two key enzymes involved in carbon incorporation, the carbonic anhydrase, and in inorganic nitrogen reduction, the nitrate reductase, of macroalgae from southern Spain are presented. During daily cycles, photoinhibition in several intertidal macroalgae, expressed as decrease in the effective quantum yield from the morning to noon time, was linearly dependent on the daily integrated irradiance. However, recovery, expressed as the increase in the effective quantum yield from noon to the afternoon, presented a different pattern; full recovery was found below daily integrated irradiance of 1.0 x10(4 kJ m-2. However, recovery reached only 50 % at higher irradiances. The existence of daily photoinhibition and full recovery in intertidal algae suggests that photoinhibition is a photoprotective mechanism against high solar radiation as in higher plants, and that patterns of photoinhibition and recovery are affected by accumulative doses. Activities of carbonic anhidrase and nitrate reductase were determined in three marine macroalgae (Plocamium cartilagineum, Ulva rigida and Fucus spiralis under full (PAR + UV-A + UV-B and excluded UV solar radiation (PAR. Under PAR + UV-A + UV-B, peaks of enzyme activity were found in P. cartilagineum during the evening, and accordingly to data previously published for other red macroalgae. This situation was modified by the absence of UV radiation since the increase in the activities was delayed several hours. In the three macroalgae and under full solar radiation, a significant and negative correlation was found only when data from nitrate reductase activity was shifted in time during at least four hours. This correlation is lost in Ulva rigida when UV radiation is excluded. The existence of these daily variations with a negative correlation of both enzyme activities could reflect a complex regulatory link between carbon and

Biodiversity on the Rocks: Macrofauna Inhabiting Authigenic Carbonate at Costa Rica Methane Seeps.

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Lisa A Levin

carbonate δ13Corg (mean = -33.83‰, which ranged from -74.4‰ to -20.6‰. Invertebrates on carbonates had average δ13C (per rock = -31.0‰ (range -18.5‰ to -46.5‰ and δ15N = 5.7‰ (range -4.5‰ to +13.4‰. Average δ13C values did not differ between active and inactive sites; carbonate fauna from both settings depend on chemosynthesis-based nutrition. Community metrics reflecting trophic diversity (SEAc, total Hull Area, ranges of δ13C and δ15N and species packing (mean distance to centroid, nearest neighbor distance also did not vary as a function of seepage activity or site. However, distinct isotopic signatures were observed among related, co-occurring species of gastropods and polychaetes, reflecting intense microbial resource partitioning. Overall, the substrate and nutritional heterogeneity introduced by authigenic seep carbonates act to promote diverse, uniquely adapted assemblages, even after seepage ceases. The macrofauna in these ecosystems remain largely overlooked in most surveys, but are major contributors to biodiversity of chemosynthetic ecosystems and the deep sea in general.

Heavy metal concentrations in macroalgae species from Sinop coasts of the Southern Black Sea

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Levent Bat

2016-10-01

Full Text Available Objective: To determine the concentrations of Fe, Zn, Ni, Cu, Mn, Pb, Cd and Co in macroalgae from Sinop coasts of the Sounthern Black Sea. Methods: Chlorophyta-green algae (Chaetomorpha spp., Cladophora spp., Ulva linza, Ulva intestinalis, Ulva lactuca, Ulva rigida; Ochrophyta-brown alga [Cystoseira barbata (C. barbata] and Rhodophyta-red algae (Ceramium spp., Corallina panizzoi were collected seasonally in the year 2010 from the upper infralittoral zone of inner harbour, outer harbour, Gerze and Ayancık of Sinop coasts of the Black Sea. The samples were analysed by atomic absorption spectrophotometer in order to determine heavy metal levels in different algal division species along Sinop coasts and to provide information of marine environment quality as marine strategy framework directive is aimed to ensure good environmental status of the seas by 2020 in the European Union. Results: The results showed that metal concentrations in all studied green algae, brown alga and red algae increase in the order: Cd < Co < Ni < Pb < Cu < Zn < Mn < Fe, Cd < Co < Cu < Ni < Pb < Mn < Zn < Fe and Co < Cd < Ni < Cu < Pb < Mn < Zn < Fe, respectively. In all divisions, among the essential elements the highest concentrations exhibited by Fe, in Gerze station- (2328 ± 89 µg/g dry weight in Chaetomorpha spp.; (2143 ± 78 µg/g dry weight in C. barbata and (968 ± 20 µg/g dry weight in Ceramium spp. Conclusions: The highest accumulation of different metals in the analysed algae species were: Fe and Co in Chaetomorpha spp., Zn in C. barbata, Ni and Cu in Ulva linza, Mn in Ulva intestinalis, Pb and Cd in Corallina panizzoi.

Potential of using tropical brown macroalgae sargassum cristaefolium meal in the diets for juvenile white shrimp (litopenaeus vannamei)

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Sudaryono, A.; Sukardi, P.; Yudiarti, E.; Hardi, E. H.; Hastuti, S.; Susilowati, T.

2018-04-01

The objectives of this study were to evaluate the effect of different dietary levels of tropical marine brown macroalgae, Sargassum cristaefolium meal (SCM) on growth performance and feed utilization efficiency of juvenile white shrimp, Litopenaeus vannamei (mean initial weight 2.65±0.1 g). The algae were collected from Bandengan Coast, Jepara, Indonesia. The study used a completely randomized design with 5 treatments of dietary different S. cristaefolium meal levels (0, 10, 20, 30, and 40 g algae meal/kg feed) in triplicates. The results showed that the different levels of dietary SCM did not significantly affect (P>0.05) average daily growth (ADG;.204-224 mg/day) and survival (80-97%) of the shrimp after a 42-day feeding period. However, the test diets significantly affected (P<0.05) feed intake (FI), feed conversion ratio (FCR), and protein efficiency ratio (PER). Better FCR (2.13) and PER (1.34) was found by the diet with 2% SCM compared to the control diet (no SCM) (FCR 3.42 and PER 0.81). This finding indicates that the supplement of dietary 2% SCM (20 g/kg feed) can increase the feed utilization efficiency up to 62% or reduce the FCR up to 38% without any adverse in growth performance.

Diversité de la macrofaune des sols cultivés sur les Hautes-Terres de Madagascar

Directory of Open Access Journals (Sweden)

Rakotomanga, D.

2016-01-01

Full Text Available Crop management and soil macrofauna diversity in the Highlands of Madagascar. Description of the subject. This article deals with soil macrofauna as a key component of soil biological functioning. Objectives. This original study, performed in 2015, aimed to compare the effect of contrasted land uses and cultural practices on soil macrofauna in a crop-livestock area in the Madagascar Highlands. Five cropping systems were investigated: annual crops under tillage with low (LAMF and high (LAEF manure inputs, permanent tilled forage crops with high manure inputs (CFEF, crops under conservation agriculture without tillage or permanent mulch cover and with medium manure inputs (ACMF, and permanent pastures without tillage and without manure (PP0F. Method. In each of these five cropping systems, soil macrofauna was sampled in 12 plots from experimental trials and smallholder farms at the end of the rainy season. In each plot, soil macrofauna was hand-sorted from five soil monoliths at a 0-30 cm depth. Results. Fifty-two species were identified and organized into 15 orders and six functional groups. In the annual cropping systems (ACMF, the absence of tillage and the presence of a permanent soil cover increased soil macrofauna diversity and density without reducing harmful white grubs (Scarabeoid beetle larvae, while earthworm density was reduced in comparison with the CFEF system. In conventional tillage cropping systems, manure input intensity (LAMF versus LAEF had no specific effects on white grubs or earthworms. Conclusions. This study on soil macrofauna in the Highlands of Madagascar helped to establish which agricultural practices and farming systems are favourable to beneficial soil invertebrates such as earthworms, and unfavourable to harmful insects such as white grubs. This will help farmers to achieve a more sustainable crop management.

Comparative bioavailability of radionuclides in macroalgae from Black sea coastal environment

International Nuclear Information System (INIS)

Strezov, A.; Nonova, Tz.; Christoskova, M.

2004-01-01

Radionuclide and heavy metal content is measured by gamma spectroscopy and Atomic Absorption Spectroscopy in the commonest species of the Black Sea red, brown, and green macroalgae, sampled in the period 1996 - 2002. Radionuclide content was measured in ten different macrophytic algae species (five green: Cladophora vagabunda, Ulva rigida, Enteromorpha intestinal, Chaetomorpha gracilis, Bryopsis plumosa; two brown: Cystoseira crinita and Cystoseira barbata; three red: Ceramium rubrum, Callithamnium corymbosum, Corallina officinalis) from eleven sampling locations for eight consecutive years. The measured concentrations of artificial and natural gamma emitters in algae depend on the alga species. The obtained range for 137 Cs in algae is 1.2 - 26 Bq/kg. The average values for the natural nuclides are 238 U - 13 Bq/kg; 232 Th - 6 Bq/kg and for 226 Ra - 8 Bq/kg. The measured natural nuclides in the species Bryopsis plumosa are with two orders of magnitude higher than other species at the same location. Significant differences in Cs-137 concentrations were found among different species growing under similar environmental conditions at same locations, suggesting that uptake does not follow physical levels but influenced by allometric parameters and physiological mechanisms. Cs-137 content in collected sea algae follows the descending order: Ceramium rubrum , Cladophora vagabunda, Cystoseira barbata, Cystoseira crinita, Enteromorpha intestinalis, Ulva rigida, Callithamnium corymbosum, Corallina officinalis, Chaetomorpha gracilis. A comparison of the stations studied indicated that the accumulation degree is also dependent on the geomorphology of the specific area. Higher levels are obtained in the northern part of the Black Sea basin due to current circulation originating from the outflow of the rivers Danube, Dnyepr and Dnester, also at the south part of the Black sea coast. It is concluded that the general dispersion of Cs-137 results from the water circulation regime

The role of the macro-invertebrates, like indicators of fertility and perturbation of hillsides soils

International Nuclear Information System (INIS)

Feijoo M, Alexander; Knapp, Edwjn B

1998-01-01

Species diversity and activity of soil fauna have been identified as making important contribution to the functioning of tropical agro-ecosystems through diverse processes. This study to compared and contrasted, from April-September of 1994, macrofauna density total, biomass and the species diversity of earthworms across a range of land use types in a typical Andean hillside watershed with the eventual goal of managing soil macrofauna to improve soil health. The methodology used is that re-commended by the TSBF project. Results indicate macrofauna density, biomass and species diversity of earthworm vary considerably across LUT both with respect to sampling depth and date. This is an important finding because variable sampling periods will add variability to survey results in the event a soil quality indicator based on macrofauna index would be a possibility. Initial factor analysis (principle components) resulted in 3 factors accounting for 71.83% of the total variance in macrofauna density. Extreme values for diversity are presented: in the Andean forest 60 taxonomic units were observed while in land pasture (28, 17 and 13) and in land farm (31, 18) they decreased dramatically

Toxic effect of nonylphenol on the marine macroalgae Gracilaria lemaneiformis (Gracilariales, Rhodophyta): antioxidant system and antitumor activity.

Science.gov (United States)

Zhong, Mingqin; Yin, Pinghe; Zhao, Ling

2017-04-01

The objective of the present work was to evaluate the toxic effect of nonylphenol (NP) on the antioxidant response and antitumor activity of Gracilaria lemaneiformis. An obvious oxidative damage was observed in this study. The thallus exposed to NP showed 1.2-2.0-fold increase in lipid peroxide and displayed a maximum level of 16.58 μmol g -1 Fw on 0.6 mg L -1 for 15-day exposure. The activities of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) enhanced significantly by 1.1-3.2-fold and subsequently diminished at the high concentrations and prolonged exposure. The results of DNA damage in comet assay also supported that NP was obviously toxic on G. lemaneiformis with increasing the percentage of tail DNA in a dose-dependent manner. Furthermore, the ethanol extract of G. lemaneiformis (EEGL) did exhibit antitumor potential against HepG-2 cells. While decreased in cell inhibition, ROS generation, apoptosis, and caspase-3 in HepG-2 cells treated with the EEGL were observed when G. lemaneiformis was exposed to NP for 15 days, and which were related to exposure concentration of NP. These suggested that NP has strongly toxic effect on the antitumor activity of G. lemaneiformis. The results revealed in this study imply that macroalgae can be useful biomarkers to evaluate marine pollutions.

Short-term impact of deep sand extraction and ecosystem-based landscaping on macrozoobenthos and sediment characteristics.

Science.gov (United States)

de Jong, Maarten F; Baptist, Martin J; Lindeboom, Han J; Hoekstra, Piet

2015-08-15

We studied short-term changes in macrozoobenthos in a 20m deep borrow pit. A boxcorer was used to sample macrobenthic infauna and a bottom sledge was used to sample macrobenthic epifauna. Sediment characteristics were determined from the boxcore samples, bed shear stress and near-bed salinity were estimated with a hydrodynamic model. Two years after the cessation of sand extraction, macrozoobenthic biomass increased fivefold in the deepest areas. Species composition changed significantly and white furrow shell (Abra alba) became abundant. Several sediment characteristics also changed significantly in the deepest parts. Macrozoobenthic species composition and biomass significantly correlated with time after cessation of sand extraction, sediment and hydrographical characteristics. Ecosystem-based landscaped sand bars were found to be effective in influencing sediment characteristics and macrozoobenthic assemblage. Significant changes in epifauna occurred in deepest parts in 2012 which coincided with the highest sedimentation rate. We recommend continuing monitoring to investigate medium and long-term impacts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Promotion of hydrogen-rich gas and phenolic-rich bio-oil production from green macroalgae Cladophora glomerata via pyrolysis over its bio-char.

Science.gov (United States)

Norouzi, Omid; Jafarian, Sajedeh; Safari, Farid; Tavasoli, Ahmad; Nejati, Behnam

2016-11-01

Conversion of Cladophora glomerata (C. glomerata) as a Caspian Sea's green macroalgae into gaseous, liquid and solid products was carried out via pyrolysis at different temperatures to determine its potential for bio-oil and hydrogen-rich gas production for further industrial utilization. Non-catalytic tests were performed to determine the optimum condition for bio-oil production. The highest portion of bio-oil was retrieved at 500°C. The catalytic test was performed using the bio-char derived at 500°C as a catalyst. Effect of the addition of the algal bio-char on the composition of the bio-oil and also gaseous products was investigated. Pyrolysis derived bio-char was characterized by BET, FESEM and ICP method to show its surface area, porosity, and presence of inorganic metals on its surface, respectively. Phenols were increased from 8.5 to 20.76area% by the addition of bio-char. Moreover, the hydrogen concentration and hydrogen selectivity were also enhanced by the factors of 1.37, 1.59 respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sulfated Polysaccharides in the Freshwater Green Macroalga Cladophora surera Not Linked to Salinity Adaptation.

Science.gov (United States)

Arata, Paula X; Alberghina, Josefina; Confalonieri, Viviana; Errea, María I; Estevez, José M; Ciancia, Marina

2017-01-01

The presence of sulfated polysaccharides in cell walls of seaweeds is considered to be a consequence of the physiological adaptation to the high salinity of the marine environment. Recently, it was found that sulfated polysaccharides were present in certain freshwater Cladophora species and some vascular plants. Cladophora (Ulvophyceae, Chlorophyta) is one of the largest genera of green algae that are able to grow in both, seas and freshwater courses. Previous studies carried out on the water-soluble polysaccharides of the marine species C. falklandica established the presence of sulfated xylogalactoarabinans constituted by a backbone of 4-linked β-L-arabinopyranose units partially sulfated mainly on C3 and also on C2 with partial glycosylation, mostly on C2, with terminal β-D-xylopyranose or β-D-galactofuranose units. Besides, minor amounts of 3-, 6- and/or 3,6-linked β-D-galactan structures, with galactose in the pyranosic form were detected. In this work, the main water soluble cell wall polysaccharides from the freshwater alga Cladophora surera were characterized. It was found that this green alga biosynthesizes sulfated polysaccharides, with a structure similar to those found in marine species of this genus. Calibration of molecular clock with fossil data suggests that colonization of freshwater environments occurred during the Miocene by its ancestor. Therefore, the presence of sulfated polysaccharides in the freshwater green macroalga C. surera could be, in this case, an adaptation to transient desiccation and changes in ionic strength. Retention of sulfated polysaccharides at the cell walls may represent a snapshot of an evolutionary event, and, thus constitutes an excellent model for further studies on the mechanisms of sulfation on cell wall polysaccharides and environmental stress co-evolution.

Sulfated Polysaccharides in the Freshwater Green Macroalga Cladophora surera Not Linked to Salinity Adaptation

Directory of Open Access Journals (Sweden)

Paula X. Arata

2017-11-01

Full Text Available The presence of sulfated polysaccharides in cell walls of seaweeds is considered to be a consequence of the physiological adaptation to the high salinity of the marine environment. Recently, it was found that sulfated polysaccharides were present in certain freshwater Cladophora species and some vascular plants. Cladophora (Ulvophyceae, Chlorophyta is one of the largest genera of green algae that are able to grow in both, seas and freshwater courses. Previous studies carried out on the water-soluble polysaccharides of the marine species C. falklandica established the presence of sulfated xylogalactoarabinans constituted by a backbone of 4-linked β-L-arabinopyranose units partially sulfated mainly on C3 and also on C2 with partial glycosylation, mostly on C2, with terminal β-D-xylopyranose or β-D-galactofuranose units. Besides, minor amounts of 3-, 6- and/or 3,6-linked β-D-galactan structures, with galactose in the pyranosic form were detected. In this work, the main water soluble cell wall polysaccharides from the freshwater alga Cladophora surera were characterized. It was found that this green alga biosynthesizes sulfated polysaccharides, with a structure similar to those found in marine species of this genus. Calibration of molecular clock with fossil data suggests that colonization of freshwater environments occurred during the Miocene by its ancestor. Therefore, the presence of sulfated polysaccharides in the freshwater green macroalga C. surera could be, in this case, an adaptation to transient desiccation and changes in ionic strength. Retention of sulfated polysaccharides at the cell walls may represent a snapshot of an evolutionary event, and, thus constitutes an excellent model for further studies on the mechanisms of sulfation on cell wall polysaccharides and environmental stress co-evolution.

Benthic macrofauna

Digital Repository Service at National Institute of Oceanography (India)

Ansari, Z.A.; Sivadas, S.; Ingole, B.S.

in the Pichavaram mangroves (South India); Ciencias Marinas 20 371?391. Goswami S. C. (1983) Coexistence and succession of copepod species in the Mandovi and Zuari estuaries, Goa; Mahasagar 16 251?258. Government of Goa (1976) Goa, Daman and Diu Agricultural Tenancy...

Short-term impact of deep sand extraction and ecosystem-based landscaping on macrozoobenthos and sediment characteristics

NARCIS (Netherlands)

de Jong, Maarten F.; Baptist, Martin J.; Lindeboom, Han J.; Hoekstra, Piet

2015-01-01

We studied short-term changes in macrozoobenthos in a 20. m deep borrow pit. A boxcorer was used to sample macrobenthic infauna and a bottom sledge was used to sample macrobenthic epifauna. Sediment characteristics were determined from the boxcore samples, bed shear stress and near-bed salinity were

Phanerozoic changes in hardpart availability and utilization in benthic communities: evolutionary ecology or evolutionary stratigraphy

Energy Technology Data Exchange (ETDEWEB)

Kidwell, S.M.

1985-01-01

Published experiments on modern communities and quantitative data from Miocene assemblages indicate that the accumulation of dead hardparts can drive specific changes in the composition of benthic communities (taphonomic feedback). Both opportunities and pathways of taphonomic feedback have changed over the Phanerozoic, however, owing to the evolution and environmental expansion of hardpart producers, utilizers, and destroyers. These changes were tracked using semi-quantitative estimates of hardpart availability based on familial diversity of the most abundant taxa, scored according to preservation potential at or near the seafloor. The data suggest a dramatic increase in hardpart availability from the Cambrian into the later Paleozoic, with a decline through the Mesozoic and Cenozoic related to the loss or dramatic reduction in calcitic epifauna, recliners on soft substrata, and large shelled nekton/plankton. The reduction in opportunities for taphonomic feedback among epifauna was accompanied by an increase in levels of infaunal interactions in the Cenozoic, which is characterized by fully three-dimensional shell gravels. In addition to evolutionary change in body sizes of hardpart producers and biotically-driven declines in certain benthic life habits, the change in pathways of taphonomic feedback was also a consequence of the large-scale shift from predominantly carbonate sedimentation in the Paleozoic to predominantly terrigenous sedimentation in the Cenozoic. For example, the waning of epifauna-dominated communities is closely associated with the restriction of level-bottom carbonate environments through the late Mesozoic and Cenozoic. The global evolution of sedimentary environments and their relative representation is important not only in its consequences for sampling but as a driving mechanism of evolutionary ecology of marine benthos.

Bioaccumulation of aluminium in the seagrasses Cymodocea nodosa (Ucria) Aschers. and Posidonia oceanica (L.) Delile and macroalgae of the Gulf of Antikyra (Greece)

Energy Technology Data Exchange (ETDEWEB)

Malea, P. [Thessaloniki Univ. (Greece). Inst. of Botany

1993-12-31

Mean concentrations of Aluminium ({+-}SE) in two seagrasses, four Chlorophytes, three Chromophytes and seven Rhodophyte species from the Gulf of Antikyra (Greece) decreased in the order: Chlorophyta > Chromophyta > Rhodophyta > P. oceanica > C. nodosa. This area is of particular interest because of the bauxite composition of the substrate and of the wate discharge from an aluminium factory in the Gulf. Aluminium concentrations in the two seagrasses were evenly distributed at the Gulf stations. Only the concentrations of Al in C. nodosa displayed significant seasonal variation. The mean concentrations increased from spring to summer, at which point they reached their maxima. This pattern is discussed in relation to the leaf-age of the seagrass. Regarding the amount of Al accumulated by the macroalgae of each division, there were interspecific differences which were attributed to differences in the structure, the ecology and the binding sites offered by the plants. The dependence of Al concentrations in the macrophytes on the concentrations in the sediment and the correlation of Al concentrations with the concentrations of some other metals in the plants were also investigated. (orig.)

Separation of Native Allophycocyanin and R-Phycocyanin from Marine Red Macroalga Polysiphonia urceolata by the Polyacrylamide Gel Electrophoresis Performed in Novel Buffer Systems

Science.gov (United States)

Wang, Yu; Gong, Xueqin; Wang, Shumei; Chen, Lixue; Sun, Li

2014-01-01

Three buffer systems of Imidazole−Acetic acid, HEPES−Imidazole/Bis-tris and Bis-tris−HEPES−MES were designed based on the principle of discontinuous polyacrylamide gel electrophoresis (PAGE) for the native PAGE which could be performed in pH 7.0 and 6.5 in order to analyze and prepare the minor components of allophycocyanin (AP) and R-phycocyanin (R-PC) from marine red macroalga Polysiphonia urceolata. These AP and R-PC phycobiliproteins are easily denatured in alkaline environments. The obtained results demonstrated that the PAGE modes performed in the buffer systems of HEPES−Imidazole/Bis-tris and Bis-tris−HEPES−MES gave the satisfactory resolution and separation of AP and R-PC proteins. The absorption and fluorescence spectra of the AP and R-PC proteins which were prepared by the established PAGE modes proved that they maintained natural spectroscopic characteristics. The established PAGE modes may also provide useful references and selections for some other proteins that are sensitive to alkaline environments or are not effectively separated by the classical PAGE modes performed normally in alkaline buffer systems. PMID:25166028

Biodiversity and community composition of sediment macrofauna associated with deep-sea Lophelia pertusa habitats in the Gulf of Mexico

Science.gov (United States)

Demopoulos, Amanda W.J.; Bourque, Jill R.; Frometa, Janessy

2014-01-01

Scleractinian corals create three-dimensional reefs that provide sheltered refuges, facilitate sediment accumulation, and enhance colonization of encrusting fauna. While heterogeneous coral habitats can harbor high levels of biodiversity, their effect on the community composition within nearby sediments remains unclear, particularly in the deep sea. Sediment macrofauna from deep-sea coral habitats (Lophelia pertusa) and non-coral, background sediments were examined at three sites in the northern Gulf of Mexico (VK826, VK906, MC751, 350–500 m depth) to determine whether macrofaunal abundance, diversity, and community composition near corals differed from background soft-sediments. Macrofaunal densities ranged from 26 to 125 individuals 32 cm−2 and were significantly greater near coral versus background sediments only at VK826. Of the 86 benthic invertebrate taxa identified, 16 were exclusive to near-coral habitats, while 14 were found only in background sediments. Diversity (Fisher’s α) and evenness were significantly higher within near-coral sediments only at MC751 while taxon richness was similar among all habitats. Community composition was significantly different both between near-coral and background sediments and among the three primary sites. Polychaetes numerically dominated all samples, accounting for up to 70% of the total individuals near coral, whereas peracarid crustaceans were proportionally more abundant in background sediments (18%) than in those near coral (10%). The reef effect differed among sites, with community patterns potentially influenced by the size of reef habitat. Taxon turnover occurred with distance from the reef, suggesting that reef extent may represent an important factor in structuring sediment communities near L. pertusa. Polychaete communities in both habitats differed from other Gulf of Mexico (GOM) soft sediments based on data from previous studies, and we hypothesize that local environmental conditions found near L

Biodiversity and community composition of sediment macrofauna associated with deep-sea Lophelia pertusa habitats in the Gulf of Mexico

Science.gov (United States)

Demopoulos, Amanda W. J.; Bourque, Jill R.; Frometa, Janessy

2014-11-01

Scleractinian corals create three-dimensional reefs that provide sheltered refuges, facilitate sediment accumulation, and enhance colonization of encrusting fauna. While heterogeneous coral habitats can harbor high levels of biodiversity, their effect on the community composition within nearby sediments remains unclear, particularly in the deep sea. Sediment macrofauna from deep-sea coral habitats (Lophelia pertusa) and non-coral, background sediments were examined at three sites in the northern Gulf of Mexico (VK826, VK906, MC751, 350-500 m depth) to determine whether macrofaunal abundance, diversity, and community composition near corals differed from background soft-sediments. Macrofaunal densities ranged from 26 to 125 individuals 32 cm-2 and were significantly greater near coral versus background sediments only at VK826. Of the 86 benthic invertebrate taxa identified, 16 were exclusive to near-coral habitats, while 14 were found only in background sediments. Diversity (Fisher's α) and evenness were significantly higher within near-coral sediments only at MC751 while taxon richness was similar among all habitats. Community composition was significantly different both between near-coral and background sediments and among the three primary sites. Polychaetes numerically dominated all samples, accounting for up to 70% of the total individuals near coral, whereas peracarid crustaceans were proportionally more abundant in background sediments (18%) than in those near coral (10%). The reef effect differed among sites, with community patterns potentially influenced by the size of reef habitat. Taxon turnover occurred with distance from the reef, suggesting that reef extent may represent an important factor in structuring sediment communities near L. pertusa. Polychaete communities in both habitats differed from other Gulf of Mexico (GOM) soft sediments based on data from previous studies, and we hypothesize that local environmental conditions found near L. pertusa

Sulphated galactopyran derived from Gracilaria opuntia, a marine macroalgae restores the antioxidant metabolic enzymes during STZ induced diabetic rats

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Lavanya Rayapu

2017-02-01

Full Text Available Objective: To screen the effect of sulphated galactopyran fraction isolated from Gracilaria opuntia (G. opuntia (FM4 in streptozotocin (STZ induced diabetic rats. Methods: In vitro antioxidant assays of FM4 were estimated by DPPH, ABTS, hydroxyl free radical and Nitric oxide free radical activities. FM4 was purified and characterized by 1H-NMR spectra and FTIR as sulphated galactopyran. Diabetes was induced intraperitonially by single dose of STZ (55 mg/kg body weight. FM4 was administrated orally (80, 100, 125 mg/kg BW to diabetic rats for 60 days. The enzymatic and non-enzymatic antioxidants such as superoxide dismutase (SOD, glutathione peroxidase (GPx, catalase (CAT, glutathione-S-transferase (GST, lipid peroxidase (LPx, glutathione reduced (GSH, vitamin-C (VIT-C and vitamin-E (VIT-E levels were estimated. Glibenclamide was used as standard drug. Results: Our results demonstrated that the aqueous extract of G. opuntia possess free radical scavenging activity. During FM4 fraction treatment (100 mg/kg BW, the SOD, GPx, CAT, GST, GSH, VIT-C and VIT-E levels were significantly (P < 0.05 increased, and the LPx levels were decreased in different organs such as liver, kidney, brain and pancreas of diabetic rats. Conclusions: The sulphated galactopyran fraction of the marine macroalgae (G. opuntia possesses the antioxidant activity which might help in the prevention of oxidative damage that occurs during diabetes.

Benthic macroalgae as biological indicators of heavy metal pollution in the marine environments: a biomonitoring approach for pollution assessment.

Science.gov (United States)

Chakraborty, Sukalyan; Bhattacharya, Tanushree; Singh, Gurmeet; Maity, Jyoti Prakash

2014-02-01

Metal pollution in the marine coastline environment is an important topical issue in the context of ecological disturbance and climate change. Heavy metal contaminations (Cd, Cr, Cu, Mn, Ni, Pb and Zn) in seawater and surficial sediments, as well as macroalgal diversity, were determined in six different locations along the coast of the Gulf of Kutch in India. The marine coastline environment was found to be enriched with Cd and Zn in comparison to other metals. Significant (p ≤ 0.05) inter-elemental positive-correlations were observed between Fe-Mn, Fe-Cu, Fe-Cr, Fe-Zn, Cr-Cu, Cu-Mn, and Cd-Zn, as well as negative-correlations between Cd-Pb, Ni-Pb, and Zn-Pb. Though genus specific macroalgal responses to heavy metal accumulation were significant, species specific response was insignificant (p ≤ 0.05). The relative abundance of metals in macroalgae followed the order of Fe>Zn>Mn>Cu>Cd>Cr>Ni>Pb. The high uptake of metals in green algae (Ulva lactuca and Enteromorpha intestinalis) and brown algae (Padina gymnospora and Dictyota bartayresiana) suggested that these algae may be used as potential biomonitors for heavy metal pollution. Three pollution indicators, Contamination Factor (CF), Enrichment Factor (EF) and Geochemical Index (Igeo) were calculated to determine the degree of metal pollution in the marine coastline and the contribution of anthropogenic influence. © 2013 Published by Elsevier Inc.

Hysteresis in coral reefs under macroalgal toxicity and overfishing.

Science.gov (United States)

Bhattacharyya, Joydeb; Pal, Samares

2015-03-01

Macroalgae and corals compete for the available space in coral reef ecosystems.While herbivorous reef fish play a beneficial role in decreasing the growth of macroalgae, macroalgal toxicity and overfishing of herbivores leads to proliferation of macroalgae. The abundance of macroalgae changes the community structure towards a macroalgae-dominated reef ecosystem. We investigate coral-macroalgal phase shifts by means of a continuous time model in a food chain. Conditions for local asymptotic stability of steady states are derived. It is observed that in the presence of macroalgal toxicity and overfishing, the system exhibits hysteresis through saddle-node bifurcation and transcritical bifurcation. We examine the effects of time lags in the liberation of toxins by macroalgae and the recovery of algal turf in response to grazing of herbivores on macroalgae by performing equilibrium and stability analyses of delay-differential forms of the ODE model. Computer simulations have been carried out to illustrate the different analytical results.

Author Details

African Journals Online (AJOL)

Abstract PDF · Vol 14, No 4 (1979) - Articles Studies on the littoral seaweed epifauna of St. Croix Island. I. Physical and biological features of the littoral zone. Abstract PDF · Vol 14, No 4 (1979) - Articles Aspects of the biology, ecology and seasonal fluctuations in biochemical conlposition of Donax serra in 'the East Cape

Benthic O₂ exchange across hard-bottom substrates quantified by eddy correlation in a sub-Arctic fjord

DEFF Research Database (Denmark)

Glud, Ronnie N.; Berg, Peter; Hume, Andrew

2010-01-01

to 27 mmol O2 m–2 d–1, which per unit area is similar to the pelagic gross production of the central fjord. Carbon fixed by benthic diatoms and coralline red algae was efficiently recycled by microbes or grazed by the abundant epifauna. (3) A vertical cliff covered with sea cucumbers also revealed high...

A comparative study on the quality of bio-oil derived from green macroalga Enteromorpha clathrata over metal modified ZSM-5 catalysts.

Science.gov (United States)

Wang, Shuang; Cao, Bin; Liu, Xinlin; Xu, Lujiang; Hu, Yamin; Afonaa-Mensah, Stephen; Abomohra, Abd El-Fatah; He, Zhixia; Wang, Qian; Xu, Shannan

2018-05-01

The green macroalga Enteromorpha clathrata was pyrolyzed with or without catalysts at the temperature of 550 °C for producing high-quality bio-oil. The ZSM-5 and 1,2,3 mmol Mg-Ce/ZSM-5 catalysts were introduced to investigate the yields and components distribution of bio-oil. Increase of bio-oil production was obtained with the use of ZSM-5 and 1,2,3 mmol Mg-Ce/ZSM-5 catalysts. The 1 mmol Mg-Ce/ZSM-5 catalyst exhibited more promising property for promoting the relative content of C 5 -C 7 compounds, and decreasing the relative content of acids in bio-oil. The results suggested that E. clathrata had potential as pyrolysis feedstocks for producing the high-quality bio-oil with large amounts of C 5 -C 7 compounds and low relative content of acids when the 1 mmol Mg-Ce/ZSM-5 catalyst was used. Furthermore, the physicochemical properties of ZSM-5 and 1 mmol Mg-Ce/ZSM-5 catalysts were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed desorption of ammonia. Copyright © 2018 Elsevier Ltd. All rights reserved.

Organic matter recycling during a mucilage event and its influence on the surrounding environment (Ligurian Sea, NW Mediterranean)

Science.gov (United States)

Misic, Cristina; Schiaparelli, Stefano; Harriague, Anabella Covazzi

2011-04-01

The development of benthic mucilage in the Marine Protected Area of Portofino (Ligurian Sea) during the summer of 2009 was studied to verify the influence of this event on the surrounding environment (seawater and soft-bottom). The calm meteorological and sea conditions at the beginning of the time frame under consideration caused the thermal stratification of the water column. This stratification was one of the driving factors influencing the development of the mucilage, which developed on a large boulder surface above the pycnocline. Mucilage was progressively detached from the boulder surface by hydrodynamism, together with macroalgae, and sank onto the sediment below the thermocline. Increased surface-water movements, caused by meteorological forcing during the study period, influenced the aggregation-disaggregation of mucilage flocks above the thermocline, leading to increased dissolved oxygen concentrations and enhanced production and turnover of the organic matter (OM). Mixing with the adjacent seawater led to the fertilisation of the surrounding environment with potentially labile OM and inorganic phosphorus, which caused increases in the hydrolytic enzymatic activity. Conversely, below the thermocline, the sunken mucilage and algae aggregates supported a heterotrophic consumption system. Dissolved oxygen concentrations were lower than those recorded in the mucilage lying above the thermocline, making more carbohydrates than proteins and labile phosphorus available. Despite the slow oxygenation of this mucilage, it contributed to the food supply for the soft-bottom macrofauna, which showed an increase in density, diversity and biomass during the study. These results suggest that the development and fate of the mucilage, as well as its interactions with the surrounding environment, were principally regulated by physical features. In the oligotrophic coastal area of the Ligurian Sea, certain compartments of the ecosystem were able to promptly respond and take

Using nitrogen stable isotope ratios (δ15N) of macroalgae to determine the effectiveness of sewage upgrades: changes in the extent of sewage plumes over four years in Moreton Bay, Australia

International Nuclear Information System (INIS)

Costanzo, Simon D.; Udy, James; Longstaff, Ben; Jones, Adrian

2005-01-01

Nitrogen loading to aquatic ecosystems from sewage is recognised worldwide as a growing problem. The use of nitrogen stable isotopes as a means of discerning sewage nitrogen in the environment has been used annually by the Ecosystem Health Monitoring Program in Moreton Bay (Australia) since 1997 when the technique was first developed. This ('sewage plume mapping') technique, which measures the δ 15 N isotopic signature of the red macroalga Catenella nipae after incubation in situ, has demonstrated a large reduction in the magnitude and spatial extent of sewage nitrogen within Moreton Bay over the past 5 years. This observed reduction coincides with considerable upgrades to the nitrogen removal efficacy at several sewage treatment plants within the region. This paper describes the observed changes and evaluates whether they can be attributed to the treatment upgrades

Mussel dredging: Impact on epifauna in Limfjorden, Denmark

DEFF Research Database (Denmark)

Dolmer, Per

2002-01-01

Species composition and population density of epibenthos are described in two areas in Limfjorden, Denmark. Both areas covered both a mussel fishing ground and an area that has been permanently closed for mussel dredging since 1988. Furthermore, mussels were dredged in a part of the mussel fishing...... grounds in both areas four months before the investigations. The rest of the fishing grounds had not been exploited for at least four years. This study describes the short-term impact (4 mo) and long-term impact (>4 y) of mussel dredging using the permanently closed areas as controls. The data were...... analyzed by multivariate statistics. In both short-term study areas significant effects of dredging were observed. A number of taxa (sponges, echinoderms, anthozoans, molluscs, crustaceans, and ascidians) had a reduced density or were not observed in fished areas four months after the fishing was ended...

A biorefinery concept using the green macroalgae Chaetomorpha linum for the coproduction of bioethanol and biogas

International Nuclear Information System (INIS)

Ben Yahmed, Nesrine; Jmel, Mohamed Amine; Ben Alaya, Monia; Bouallagui, Hassib; Marzouki, M. Nejib; Smaali, Issam

2016-01-01

Highlights: • Chaetomorpha linum was used as sustainable feedstock for co-production of bioethanol and biomethane. • An eco-friendly process was developed, only generating 0.3 ± 0.01 g/g of waste. • Ethanol yield obtained was 0.41 g/g reducing sugar. • Methane yield obtained was 0.26 ± 0.045 L/gVS. - Abstract: An innovative integrated biorefinery approach using the green macroalgae Chaetomorpha linum was investigated in the present study for the co-production of bioethanol and biogas. Among three pretreatments of C. linum biomass, consisting of acidic, neutral and alkali ones, 3% NaOH pretreatment gave the best result in terms of thallus disintegration, biomass recovery and enzymatic digestibility as demonstrated by scanning electron microscopy and saccharification tests. The hydrolysis of C. linum feedstock with a crude specific enzyme preparation, locally produced from fermentation of Aspergillus awamori, at 45 °C, pH 5 for 30 h gave the maximum yield of fermentable sugar of 0.22 ± 0.02 g/g dry substrate. An ethanol yield of 0.41 g/g reducing sugar corresponding to about 0.093 g/g pretreated algae was obtained after alcoholic fermentation by Saccharomyces cerevisiae. In the integrated proposed process, mycelium issued from the fungal fermentation, liquid issued from alkali pretreatment, residual from the non-hydrolysable biomass and all effluents and co-products represent a heterogeneous substrate that feed an anaerobic digester for biogas production. GC-analysis of this later showed that the biomethane yield reached 0.26 ± 0.045 L/gVS. This study presents therefore an eco-friendly biorefining process, which efficiently coproduce bioethanol and biomethane and generate only a single waste (0.3 ± 0.01 g/g) allowing an almost complete conversion of the algal biomass.

Time Course Exo-Metabolomic Profiling in the Green Marine Macroalga Ulva (Chlorophyta for Identification of Growth Phase-Dependent Biomarkers

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Taghreed Alsufyani

2017-01-01

Full Text Available The marine green macroalga Ulva (Chlorophyta lives in a mutualistic symbiosis with bacteria that influence growth, development, and morphogenesis. We surveyed changes in Ulva’s chemosphere, which was defined as a space where organisms interact with each other via compounds, such as infochemicals, nutrients, morphogens, and defense compounds. Thereby, Ulva mutabilis cooperates with bacteria, in particular, Roseovarius sp. strain MS2 and Maribacter sp. strain MS6 (formerly identified as Roseobacter sp. strain MS2 and Cytophaga sp. strain MS6. Without this accompanying microbial flora, U. mutabilis forms only callus-like colonies. However, upon addition of the two bacteria species, in effect forming a tripartite community, morphogenesis can be completely restored. Under this strictly standardized condition, bioactive and eco-physiologically-relevant marine natural products can be discovered. Solid phase extracted waterborne metabolites were analyzed using a metabolomics platform, facilitating gas chromatography-mass spectrometry (GC-MS and liquid chromatography-mass spectrometry (LC-MS analysis, combined with the necessary acquisition of biological metadata. Multivariate statistics of the GC-MS and LC-MS data revealed strong differences between Ulva’s growth phases, as well as between the axenic Ulva cultures and the tripartite community. Waterborne biomarkers, including glycerol, were identified as potential indicators for algal carbon source and bacterial-algal interactions. Furthermore, it was demonstrated that U. mutabilis releases glycerol that can be utilized for growth by Roseovarius sp. MS2.

Deep-water polychaetes (Annelida from the southeastern Gulf of California, Mexico

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Nuria Méndez

2006-09-01

Full Text Available Polychaetes inhabiting deep-sea soft bottoms from the southeastern Gulf of California were collected during four oceanographic cruises during 2000 and 2001. Sampling of benthic organisms was performed with a benthic sledge to collect epifauna and a Karling dredge for epifauna and infauna, in a depth range from 732 to 2 250 m. A list of the polychaetes that were collected and their distribution are presented here. A total of 73 species (distributed among 33 families were identified. Moreover, 11 species were identified only to genus level and 20 species only to family level. With the exception of Ancistrosyllis hartmanae and Melinnampharete eoa, all identified species have been previously reported in soft bottoms of the Gulf of California or in adjacent areas. Additional previously unreported information is provided herein regarding depth ranges, geographical distribution, morphology and tubes inhabited by the organisms. The morphology of the ampharetids Amage sp. and Samytha sp. does not coincide with that of other species in these genera reported for the Gulf of California, which suggests that they are probably undescribed species. Rev. Biol. Trop. 54 (3: 773-785. Epub 2006 Sept. 29.Se recolectaron anélidos poliquetos de fondos profundos del SE del golfo de California durante cuatro campañas oceanográficas entre 2000 y 2001. El muestreo de organismos bentónicos se llevó a cabo mediante una draga de arrastre bentónica para recolectar epifauna y una draga tipo Karling para epifauna y endofauna, en un intervalo de profundidad de 732 a 2 250 m. Se presenta un listado de poliquetos con su distribución dentro del área de estudio. En total se identificaron 73 especies (distribuidas en 33 familias. Además, 11 especies fueron identificadas a nivel genérico y 20 a nivel de familia. Con excepción de Ancistrosyllis hartmanae y Melinnampharete eoa, todas las especies habían sido registradas en fondos blandos del golfo de California o zonas

Evaluation of antifungal activity of seaweed extracts Avaliação de atividade antifúngica de extratos de macroalgas marinhas

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Julio Cesar Fernandes Peres

2012-06-01

Full Text Available Seaweeds are subject to numerous biological interactions and sometimes to extreme abiotic conditions, so they have developed among other defense mechanisms, the ability to produce biologically active substances. Thus, these organisms produce mainly terpenes and phenols. Among others, the antifungal activity, due to its importance in human and animal health and the production of agricultural products, has been the subject of several studies. In the present work, this activity was investigated in ten seaweeds extracts, by direct bioautography assays, compared to Colletotrichum lagenarium and disk diffusion assay, compared to Aspergillus flavus. The organisms studied were: Stypopodium zonale, Laurencia dendroidea, Ascophyllum nodosum, Sargassum muticum, Pelvetia canaliculata, Fucus spiralis, Sargassum filipendula, Sargassum stenophyllum, Laminaria hyperborea and Gracilaria edulis. S. zonale, L. dendroidea, P. canaliculata, S. muticum, A. nodosum and F. spiralis extracts significantly inhibited the C. lagenarium growth, but not inhibited significantly the A. flavus growth. The presence of terpenes in all of these extracts was confirmed by thin layer chromatography whereas the presence of phenolic compounds was confirmed only in extracts of P. canaliculata, A. nodosum and S. muticum. In chemical study by column chromatography, followed by gas chromatography/mass spectrometry analysis, the terpenes neophytadiene, cartilagineol, obtusol elatol; and the ester ethyl hexadecanoate were identified in the L. dendroidea extract. This is the first report on the activity of seaweed extracts against C. lagenarium, a fungus bearing agricultural importance.As macroalgas marinhas, por estarem sujeitas a numerosas interações biológicas e, por vezes, a condições abióticas extremas, desenvolveram, entre outros mecanismos de defesa, a capacidade de produzir substâncias biologicamente ativas. Assim, esses organismos produzem, principalmente, terpenos e fen

Water quality and communities associated with macrophytes in a shallow water-supply reservoir on an aquaculture farm.

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Sipaúba-Tavares, L H; Dias, S G

2014-05-01

Plankton communities and macrofauna associated to aquatic macrophyte stands in a shallow water-supply reservoir (21°14'09″S; 48°18'38″W) on an aquaculture farm were compared to evaluate the relationship between organism densities and some abiotic features of the reservoir. Water and communities associated were sampled at two sites, one in an area with the predominance of Eichhornia azurea (Sw.) Kunth and the other with the predominance of Salvinia auriculata Aublet. Communities associated with macrophytes were sampled with floating quadrants (0.5 m2); the macrophytes were washed and plankton and macrofauna were fixated with 4% formalin and 1% lugol iodine; the specimens were then identified and counted. Plankton and macrofauna communities associated with S. auriculata and E. azurea had a similar diversity of species but different (pmacrophytes presence in the shallow reservoir is a strong predictor of favourable conditions to maintain great diversity plankton community and macrofauna associated with plants. The role of macrophytes is important for not only stabilising the clear-water state and maintaining high diversity of organisms associated, but also it seems to be a good alternative to maintaining desirable water-supply quality for aquaculture farms.

VARIACIÓN VERTICAL Y ESTACIONAL DE LA COMUNIDAD DE MACROALGAS EN LOS COSTADOS NOROCCIDENTAL Y NORORIENTAL DEL GOLFO DE URABÀ, CARIBE COLOMBIANO

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DELGADO M. JUAN CARLOS

2010-05-01

Full Text Available Durante la época seca en febrero y la época de lluvias en junio de 2004, fueron ubicados en el Golfo de Urabá seis estaciones con transectos paralelos a la línea de costa rocosa. Allí se removió la biomasa macroalgal de ocho cuadrantes de 1 m2 por cada estación de muestreo y distribuidos desde el supralitoral hasta tres metros de profundidad. Se estimó el porcentaje de cobertura de las microalgas; se determinó la riqueza numérica de especies y las biomasas húmeda y seca; y se midieron algunas variables fisicoquímicas. Se encontró un total de 30 taxones de macroalgas de las cuales 20 pertenecen a la división Rhodophyta. cinco Phaeophyta y cinco Chorophyta. Las especies más frecuentes y con mayor biomasa para la costa noroccidental, fueron Sargassum polyceratíum. Laurencia obtusa y L papulosa y para el costado nororiental, Grateloupia fílicina y Chladophora vagabunda. Se concluyó que existieron diferencias estadísticamente significativas entre las comunidades algales de ambos costados y que las diferencias en el gradiente vertical y de la salinidad del agua, condujeron a diferencias en las comunidades establecidas sobre el litoral rocoso de ambos costados.

Ostracoda and Foraminifera associated with macrofauna of marginal marine origin in continental sabkha sediments of Tayma (NW Saudi Arabia)

Science.gov (United States)

Pint, Anna; Frenzel, Peter; Engel, Max; Plessen, Birgit; Melzer, Sandra; Brückner, Helmut

2016-04-01

The oasis Tayma in northwestern Saudi Arabia (27°38'N, 38°33'E) is well known for its rich archaeological heritage and also hosts a key sedimentary record of Holocene environmental change.The palaeontologically investigated material comes from two 5.5 m long sediment cores taken in the northeastern and central part of the sabkha and two outcrops of shoreline deposits at the northeastern and southwestern margin of a large lake. Microfossil-rich layers have an age of about 9.2-ca. 8 ka BP. The sandy and carbonate-dominated sediments contain autochthonous balanids, the gastropods Melanoides tuberculatus and hydrobiids as well as the foraminifers Ammonia tepida (Cushman, 1926), Quinqueloculina seminula (Linnaeus, 1758), and Flintionoides labiosa (d'Orbigny, 1839). This brackish water association is completed by partially mass-occurrence of Cyprideis torosa (JONES, 1850), an euryhaline and generally widely tolerant ostracod species. Only the smooth shelled morphotype littoralis occurs. The association indicates a large brackish water lake with temporary freshwater inflows. All species documented originate in the marginal marine environment of the Red or Mediterranean Sea within the intertidal zone and hence they are adapted for strong environmental changes. We assume negative water balance under arid climatic conditions as cause for the high salinity of this athalassic lake. Sieve-pore analyses and shell chemistry suppose a trend of increasing salinity towards the top of the studied microfossil-bearing sections. This pattern is confirmed by increasing test malformation ratios of foraminifers. The marine origin of the fauna is surprising in this area 250 km away from the sea in an altitude of about 800 m a.s.l. We assume an avian-mediated transport of eggs, larvae or even adult animals to this site. The brackish water character of the lake enabled a permanent settling of marginal marine foraminifers, ostracods and even macrofauna as gastropods and balanids. The studied

Methyl Jasmonate-Induced Lipidomic and Biochemical Alterations in the Intertidal Macroalga Gracilaria dura (Gracilariaceae, Rhodophyta).

Science.gov (United States)

Kumari, Puja; Reddy, C R K; Jha, Bhavanath

2015-10-01

The role of exogenously added methyl jasmonate (MeJA), a lipid-derived signaling compound, in inducing oxidative stress in the marine red macroalga Gracilaria dura was investigated. MeJA at a concentration of 1-100 µM was a strong stimulant of reactive oxygen species (H(2)O(2), HO· and O(2) (·-)) (P < 0.05) causing considerable oxidative stress in G. dura. This further led to lipid peroxidation and degradation of the pigments Chl a and phycocyanin, with a concomitant increase in phycoerythrin. The MeJA-induced oxidative burst also led to the induction of a fatty acid oxidation cascade, resulting in the synthesis of hydroxy-oxylipins and the up-regulation of the 13-lipoxygenase pathway. Electrospray ionization-mass spectrometry-based shotgun lipidomic analysis revealed that monogalactosyldiacylglycerol (a chloroplastic glycerolipid) and phosphatidylcholine (extrachloroplastidic phopholipid) were the most affected lipid classes. The degradation of 18:3-fatty acid-containing monogalactosyldiacylglycerol inferred that it provided fatty acyl chains for the biosynthesis of 13-hydroperoxylinolenic acid, which was further directed towards either the jasmonate pathway or other alternative pathways of the fatty acid oxidation cascade, analogous to higher plants. Also, G. dura modulated the lipid acyl chains in such a way that no significant change was observed in the fatty acid profile of the treated thalli as compared with those of the control, except for C16:0, C16:1 (n-9), C20:3 (n-6) and C20:4 (n-6) (P < 0.05). Furthermore, MeJA caused the accumulation of phenolic compounds and the up-regulation of enzymes involved in secondary metabolism such as polyphenol oxidase, shikimate dehydrogenase and phenylalanine ammonia-lyase, indicating a shift towards secondary metabolism as a defense strategy to combat the induced oxidative stress. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For

Levantamento florístico das macroalgas da baía de Sepetiba e adjacências, RJ: ponto de partida para o Programa GloBallast no Brasil Floristic survey of the macroalgae from Sepetiba bay and surrounding area, Rio de Janeiro State: starting point for the GloBallast Programme in Brazil

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Maria Teresa Menezes de Széchy

2005-09-01

Full Text Available O Porto de Sepetiba, Estado do Rio de Janeiro, foi escolhido, no Brasil, como área-piloto do projeto "Remoção de barreiras para a implementação efetiva do controle de água de lastro e medidas de gestão em países em desenvolvimento" (Programa GloBallast. Para possibilitar comparações, os seis países participantes do Programa GloBallast foram orientados a adotar a mesma metodologia para o levantamento preliminar da biota das áreas-pilotos valorizando a identificação em nível de espécie. O presente estudo teve como objetivo aplicar metodologia estabelecida pelo Centro para Pesquisa sobre Espécies Marinhas Introduzidas, da Austrália (Procedimento CRIMP, com algumas adaptações, no levantamento florístico das macroalgas de substratos consolidados naturais da área-piloto do Porto de Sepetiba. Coletas de macroalgas foram realizadas em novembro/2001, em nove locais da baía de Sepetiba e adjacências, desde a franja da região sublitorânea até cerca de -4 m de profundidade. Em cada local, seis quadrados de 0,1 m² de área foram raspados. O material foi depositado no Herbário do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro (RB. Das 96 espécies identificadas (20 Chlorophyta, 16 Phaeophyta, 60 Rhodophyta, 12 não haviam sido citadas anteriormente para a área de estudo. Cladophora pellucidoidea C. Hoek, Coelothrix irregularis (Harv. Boergesen e Acrochaetium savianum (Menegh. Nägeli são ocorrências novas para o Estado. Não há indícios de que as novas ocorrências equivalem a espécies recentemente introduzidas por meio das atividades portuárias. O procedimento metodológico adotado mostrou-se eficiente, resultando em listagem de espécies comparável às de levantamentos florísticos com maior esforço amostral e complementando os dados pretéritos existentes para a baía de Sepetiba e adjacências. No entanto, ressalta-se a importância de uma reavaliação das escalas temporal e espacial da estratégia de

Using nitrogen stable isotope ratios ({delta}{sup 15}N) of macroalgae to determine the effectiveness of sewage upgrades: changes in the extent of sewage plumes over four years in Moreton Bay, Australia

Energy Technology Data Exchange (ETDEWEB)

Costanzo, Simon D. [National Research Centre for Environmental Toxicology, University of Queensland, 39 Kessels Road, Coopers Plains, QLD 4108 (Australia)]. E-mail: s.costanzo@uq.edu.au; Udy, James [Marine Botany, Centre for Marine Studies, University of Queensland, 4072 (Australia); Longstaff, Ben [Environmental Protection Agency, 80 Meiers Road, Indooroopilly, QLD 4058 (Australia); Jones, Adrian [University of Maryland Center for Environmental Science, P.O. Box 775, Cambridge, MD 21613, USA (United States)

2005-07-01

Nitrogen loading to aquatic ecosystems from sewage is recognised worldwide as a growing problem. The use of nitrogen stable isotopes as a means of discerning sewage nitrogen in the environment has been used annually by the Ecosystem Health Monitoring Program in Moreton Bay (Australia) since 1997 when the technique was first developed. This ('sewage plume mapping') technique, which measures the {delta}{sup 15}N isotopic signature of the red macroalga Catenella nipae after incubation in situ, has demonstrated a large reduction in the magnitude and spatial extent of sewage nitrogen within Moreton Bay over the past 5 years. This observed reduction coincides with considerable upgrades to the nitrogen removal efficacy at several sewage treatment plants within the region. This paper describes the observed changes and evaluates whether they can be attributed to the treatment upgrades.

[Monitoring "green tide" in the Yellow Sea and the East China Sea using multi-temporal and multi-source remote sensing images].

Science.gov (United States)

Xing, Qian-Guo; Zheng, Xiang-Yang; Shi, Ping; Hao, Jia-Jia; Yu, Ding-Feng; Liang, Shou-Zhen; Liu, Dong-Yan; Zhang, Yuan-Zhi

2011-06-01

Landsat-TM (Theme Mapper) and EOS (Earth Observing System)-MODIS (MODerate resolution Imaging Spectrora-diometer) Terra/Aqua images were used to monitor the macro-algae (Ulva prolifera) bloom since 2007 at the Yellow Sea and the East China Sea. At the turbid waters of Northern Jiangsu Shoal, there is strong spectral mixing behavior, and satellite images with finer spatical resolution are more effective in detection of macro-algae patches. Macro-algae patches were detected by the Landsat images for the first time at the Sheyang estuary where is dominated by very turbid waters. The MODIS images showed that the macro-algae from the turbid waters near the Northern Jiangsu Shoal drifted southwardly in the early of May and affected the East China Sea waters; with the strengthening east-asian Summer Monsoon, macro-algae patches mainly drifted in a northward path which was mostly observed at the Yellow Sea. Macro-algae patches were also found to drift eastwardly towards the Korea Peninsular, which are supposed to be driven by the sea surface wind.

Trophic linkage of a temperate intertidal macrobenthic food web under opportunistic macroalgal blooms: A stable isotope approach

International Nuclear Information System (INIS)

Park, Hyun Je; Han, Eunah; Lee, Young-Jae; Kang, Chang-Keun

2016-01-01

The effects of blooms of opportunistic green macroalgae, Ulva prolifera, on the trophic structure of the macrobenthic food web in a temperate intertidal zone on the western coast of Korea were evaluated using carbon and nitrogen stable isotopes. Biomasses of Ulva and microphytobenthos (MPB) increased significantly at the macroalgae-bloom and the non-bloom sites, respectively, from March to September 2011. The δ 13 C values of most the consumers were arrayed between those of MPB and Ulva at both sites, and differed according to feeding strategies at the macroalgae-bloom site. Seasonally increasing magnitudes in δ 13 C and δ 15 N values of consumers were much steeper at the macroalgae-bloom site than at the non-bloom site. Our findings provide evidence that blooming green macroalgae play a significant role as a basal resource supporting the intertidal macrobenthic food web and their significance varies with feeding strategies of consumers as well as the resource availability. - Highlights: • Trophic effects of Ulva blooms on intertidal macrobenthic food web were evaluated. • Biomasses of Ulva increased at the macroalgae-bloom from March to September. • δ 13 C and δ 15 N values of consumers differed with feeding strategy and season. • Trophic significance of blooming macroalgae varies with feeding strategies of consumers. • Ulva blooms play a significant role as a basal resource supporting the intertidal food web.

Testing for the induction of anti-herbivory defences in four Portuguese macroalgae by direct and water-borne cues of grazing amphipods

Science.gov (United States)

Yun, Hee Young; Cruz, Joana; Treitschke, Michaela; Wahl, Martin; Molis, Markus

2007-09-01

Herbivory is a key factor in regulating plant biomass, thereby driving ecosystem performance. Algae have developed multiple adaptations to cope with grazers, including morphological and chemical defences. In a series of experiments we investigated whether several species of macroalgae possess anti-herbivore defences and whether these could be regulated to demand, i.e. grazing events. The potential of direct grazing on defence induction was assessed for two brown ( Dictyopteris membranacea, Fucus vesiculosus) and two red seaweeds ( Gelidium sesquipedale, Sphaerococcus coronopifolius) from São Rafael and Ria Formosa, Portugal. Bioassays conducted with live algal pieces and agar-based food containing lipophilic algal extracts were used to detect changes in palatability after exposure to amphipod attacks (=treatment phase). Fucus vesiculosus was the only species significantly reducing palatability in response to direct amphipod-attacks. This pattern was observed in live F. vesiculosus pieces and agar-based food containing a lipophilic extract, suggesting that lipophilic compounds produced during the treatment phase were responsible for the repulsion of grazers. Water-borne cues of grazed F. vesiculosus as well as non-grazing amphipods also reduced palatability of neighbouring conspecifics. However, this effect was only observed in live tissues of F. vesiculosus. This study is the first to show that amphipods, like isopods, are capable to induce anti-herbivory defences in F. vesiculosus and that a seasonally variable effectiveness of chemical defences might serve as a dynamic control in alga-herbivore interactions.

Seaweed-coral interactions: variance in seaweed allelopathy, coral susceptibility, and potential effects on coral resilience.

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Roberta M Bonaldo

Full Text Available Tropical reefs are in global decline with seaweeds commonly replacing corals. Negative associations between macroalgae and corals are well documented, but the mechanisms involved, the dynamics of the interactions, and variance in effects of different macroalgal-coral pairings are poorly investigated. We assessed the frequency, magnitude, and dynamics of macroalgal-coral competition involving allelopathic and non-allelopathic macroalgae on three, spatially grouped pairs of no-take Marine Protected Areas (MPAs and non-MPAs in Fiji. In non-MPAs, biomass of herbivorous fishes was 70-80% lower, macroalgal cover 4-9 fold higher, macroalgal-coral contacts 5-15 fold more frequent and 23-67 fold more extensive (measured as % of colony margin contacted by macroalgae, and coral cover 51-68% lower than in MPAs. Coral contacts with allelopathic macroalgae occurred less frequently than expected by chance across all sites, while contact with non-allelopathic macroalgae tended to occur more frequently than expected. Transplants of allelopathic macroalgae (Chlorodesmis fastigiata and Galaxaura filamentosa against coral edges inflicted damage to Acropora aspera and Pocillopora damicornis more rapidly and extensively than to Porites cylindrica and Porites lobata, which appeared more resistant to these macroalgae. Montipora digitata experienced intermediate damage. Extent of damage from macroalgal contact was independent of coral colony size for each of the 10 macroalgal-coral pairings we established. When natural contacts with Galaxaura filamentosa were removed in the field, recovery was rapid for Porites lobata, but Pocillopora damicornis did not recover and damage continued to expand. As macroalgae increase on overfished tropical reefs, allelopathy could produce feedbacks that suppress coral resilience, prevent coral recovery, and promote the stability of algal beds in habitats previously available to corals.

Isolation, purification and properties of an R-phycocyanin from the phycobilisomes of a marine red macroalga Polysiphonia urceolata.

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Lu Wang

Full Text Available Phycobilisomes were prepared from a marine red macroalga Polysiphonia urceolata (P. urceolata by sucrose step-gradient ultracentrifugation. From the prepared phycobilisomes, an R-phycocyanin was isolated by gel filtration on Sephadex G-150 and then purified by ion exchange chromatography on DEAE-Sepharose Fast Flow and native polyacrylamide gel electrophoresis (PAGE performed in neutral buffer systems. The purified R-phycocyanins showed not only a homogeneous trimer of 136 kDa in gel filtration and a single band in native PAGE, but also exhibited one band at about pH 5.7 in native isoelectric focusing (IEF. By a gradient SDS-PAGE the purified R-phycocyanin was determined to contain one a subunit of 17.5 kDa (α17.5 and two b subunits of 21.3 kDa and 22.6 kDa (β21.3 and β22.6. The analysis from denaturing isoelectric focusing and two-dimension PAGE demonstrated that α17.5, β21.3 and β22.6 had their pIs of 6.4, 5.3 and 5.4, respectively. Furthermore, mass spectroscopy analysis of β21.3 and β22.6 by MALDI-TOF mass spectrometry demonstrated the two b subunits had differences in peptide mass fingerprinting. These results revealed that the prepared R-phycocyanins were composed of one a and two b subunits. (α17:53 β21:32 β22:61 and (α17:53 β21:31 β22:62, which have a structural foundation to show their pIs too close for them to be definitely resolved by native IEF, are postulated to be the most possible trimeric forms of the R-phycocyanins prepared from the phycobilisomes of P. urceolata.

High mortality of Zostera marina under high temperature regimes but minor effects of the invasive macroalgae Gracilaria vermiculophylla

Science.gov (United States)

Höffle, H.; Thomsen, M. S.; Holmer, M.

2011-03-01

The present study tested for density-dependent effects of the invasive drift macroalgae Gracilaria vermiculophylla (Ohmi) Papenfuss on growth and survival of the native eelgrass, Zostera marina L., under different temperature levels. Three weeks laboratory experiments were conducted in Odense, Denmark, combining three algae densities (control, low 1.9 kg WW m -2, high 4.5 kg WW m -2) with typical Danish summer temperatures (18 °C) and elevated temperatures (21 °C and 27 °C). There was a significant effect of temperature on shoot survival with on average 68% mortality in the high temperature treatment but almost no mortality at the two lower temperatures. The higher mortality was probably caused by high sulphide levels in the sediment pore water (0.6 mmol l -1 at 18 °C compared to 3.7 mmol l -1 at 27 °C). Above-ground growth of the surviving shoots was also significantly affected by temperature, with leaf elongation rates being negatively affected, while the leaf plastochrone interval increased. Relative growth rate was significantly higher at 21 °C than at 18 °C or 27 °C, whereas rhizome elongation was significantly lowest at 27 °C. Elemental sulphur content in the plant tissues increased significantly with temperature and was up to 34 times higher (S 0 in rhizomes) at 27 °C compared to the lower temperatures. In contrast to the temperature effects, cover by G. vermiculophylla did not cause significant effects on any seagrass responses. However, there was a (non-significant) negative effect of algal cover at the highest temperature, where the seagrass is already stressed. The latter results suggest that more studies should test for interaction effects between temperature and other anthropogenic stressors given that temperature is predicted to increase in the near future.

Impact of oxy-fuel combustion gases on mercury retention in activated carbons from a macroalgae waste: effect of water.

Science.gov (United States)

Lopez-Anton, M A; Ferrera-Lorenzo, N; Fuente, E; Díaz-Somoano, M; Suarez-Ruíz, I; Martínez-Tarazona, M R; Ruiz, B

2015-04-01

The aim of this study is to understand the different sorption behaviors of mercury species on activated carbons in the oxy-fuel combustion of coal and the effect of high quantities of water vapor on the retention process. The work evaluates the interactions between the mercury species and a series of activated carbons prepared from a macroalgae waste (algae meal) from the agar-agar industry in oxy-combustion atmospheres, focussing on the role that the high concentration of water in the flue gases plays in mercury retention. Two novel aspects are considered in this work (i) the impact of oxy-combustion gases on the retention of mercury by activated carbons and (ii) the performance of activated carbons prepared from biomass algae wastes for this application. The results obtained at laboratory scale indicate that the effect of the chemical and textural characteristics of the activated carbons on mercury capture is not as important as that of reactive gases, such as the SOx and water vapor present in the flue gas. Mercury retention was found to be much lower in the oxy-combustion atmosphere than in the O2+N2 (12.6% O2) atmosphere. However, the oxidation of elemental mercury (Hg0) to form oxidized mercury (Hg2+) amounted to 60%, resulting in an enhancement of mercury retention in the flue gas desulfurization units and a reduction in the amalgamation of Hg0 in the CO2 compression unit. This result is of considerable importance for the development of technologies based on activated carbon sorbents for mercury control in oxy-combustion processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Variation in the composition of corals, fishes, sponges, echinoderms, ascidians, molluscs, foraminifera and macroalgae across a pronounced in-to-offshore environmental gradient in the Jakarta Bay-Thousand Islands coral reef complex.

Science.gov (United States)

Cleary, D F R; Polónia, A R M; Renema, W; Hoeksema, B W; Rachello-Dolmen, P G; Moolenbeek, R G; Budiyanto, A; Yahmantoro; Tuti, Y; Giyanto; Draisma, S G A; Prud'homme van Reine, W F; Hariyanto, R; Gittenberger, A; Rikoh, M S; de Voogd, N J

2016-09-30

Substrate cover, water quality parameters and assemblages of corals, fishes, sponges, echinoderms, ascidians, molluscs, benthic foraminifera and macroalgae were sampled across a pronounced environmental gradient in the Jakarta Bay-Thousand Islands reef complex. Inshore sites mainly consisted of sand, rubble and turf algae with elevated temperature, dissolved oxygen, pH and chlorophyll concentrations and depauperate assemblages of all taxa. Live coral cover was very low inshore and mainly consisted of sparse massive coral heads and a few encrusting species. Faunal assemblages were more speciose and compositionally distinct mid- and offshore compared to inshore. There were, however, small-scale differences among taxa. Certain midshore sites, for example, housed assemblages resembling those typical of the inshore environment but this differed depending on the taxon. Substrate, water quality and spatial variables together explained from 31% (molluscs) to 72% (foraminifera) of the variation in composition. In general, satellite-derived parameters outperformed locally measured parameters. Copyright © 2016 Elsevier Ltd. All rights reserved.

Coral Reef Resilience, Tipping Points and the Strength of Herbivory.

Science.gov (United States)

Holbrook, Sally J; Schmitt, Russell J; Adam, Thomas C; Brooks, Andrew J

2016-11-02

Coral reefs increasingly are undergoing transitions from coral to macroalgal dominance. Although the functional roles of reef herbivores in controlling algae are becoming better understood, identifying possible tipping points in the herbivory-macroalgae relationships has remained a challenge. Assessment of where any coral reef ecosystem lies in relation to the coral-to-macroalgae tipping point is fundamental to understanding resilience properties, forecasting state shifts, and developing effective management practices. We conducted a multi-year field experiment in Moorea, French Polynesia to estimate these properties. While we found a sharp herbivory threshold where macroalgae escape control, ambient levels of herbivory by reef fishes were well above that needed to prevent proliferation of macroalgae. These findings are consistent with previously observed high resilience of the fore reef in Moorea. Our approach can identify vulnerable coral reef systems in urgent need of management action to both forestall shifts to macroalgae and preserve properties essential for resilience.

Differential larval settlement responses of Porites astreoides and Acropora palmata in the presence of the green alga Halimeda opuntia

Science.gov (United States)

Olsen, K.; Sneed, J. M.; Paul, V. J.

2016-06-01

Settlement is critical to maintaining coral cover on reefs, yet interspecific responses of coral planulae to common benthic macroalgae are not well characterized. Larval survival and settlement of two Caribbean reef-building corals, the broadcast-spawner Acropora palmata and the planulae-brooder Porites astreoides, were quantified following exposure to plastic algae controls and the green macroalga Halimeda opuntia. Survival and settlement rates were not significantly affected by the presence of H. opuntia in either species. However, ~10 % of P. astreoides larvae settled on the surface of the macroalga, whereas larvae of A. palmata did not. It is unlikely that corals that settle on macroalgae will survive post-settlement; therefore, H. opuntia may reduce the number of P. astreoides and other non-discriminatory larvae that survive to adulthood. Our results suggest that the presence of macroalgae on impacted reefs can have unexpected repercussions for coral recruitment and highlight discrepancies in settlement specificity between corals with distinct life history strategies.

First evaluation of foraminiferal metabarcoding for monitoring environmental impact from an offshore oil drilling site

KAUST Repository

Laroche, Olivier

2016-08-29

At present, environmental impacts from offshore oil and gas activities are partly determined by measuring changes in macrofauna diversity. Morphological identification of macrofauna is time-consuming, expensive and dependent on taxonomic expertise. In this study, we evaluated the applicability of using foraminiferal-specific metabarcoding for routine monitoring. Sediment samples were collected along distance gradients from two oil platforms off Taranaki (New Zealand) and their physicochemical properties, foraminiferal environmental DNA/RNA, and macrofaunal composition analyzed. Macrofaunal and foraminiferal assemblages showed similar shifts along impact gradients, but responded differently to environmental perturbations. Macrofauna were affected by hypoxia, whereas sediment grain size appeared to drive shifts in foraminifera. We identified eight foraminiferal molecular operational taxonomic units that have potential to be used as bioindicator taxa. Our results show that metabarcoding represents an effective tool for assessing foraminiferal communities near offshore oil and gas platforms, and that it can be used to complement current monitoring techniques. (C) 2016 Elsevier Ltd. All rights reserved.

First evaluation of foraminiferal metabarcoding for monitoring environmental impact from an offshore oil drilling site

KAUST Repository

Laroche, Olivier; Wood, Susanna A.; Tremblay, Louis A.; Ellis, Joanne; Lejzerowicz, Franck; Pawlowski, Jan; Lear, Gavin; Atalah, Javier; Pochon, Xavier

2016-01-01

At present, environmental impacts from offshore oil and gas activities are partly determined by measuring changes in macrofauna diversity. Morphological identification of macrofauna is time-consuming, expensive and dependent on taxonomic expertise. In this study, we evaluated the applicability of using foraminiferal-specific metabarcoding for routine monitoring. Sediment samples were collected along distance gradients from two oil platforms off Taranaki (New Zealand) and their physicochemical properties, foraminiferal environmental DNA/RNA, and macrofaunal composition analyzed. Macrofaunal and foraminiferal assemblages showed similar shifts along impact gradients, but responded differently to environmental perturbations. Macrofauna were affected by hypoxia, whereas sediment grain size appeared to drive shifts in foraminifera. We identified eight foraminiferal molecular operational taxonomic units that have potential to be used as bioindicator taxa. Our results show that metabarcoding represents an effective tool for assessing foraminiferal communities near offshore oil and gas platforms, and that it can be used to complement current monitoring techniques. (C) 2016 Elsevier Ltd. All rights reserved.

A new macrofaunal limit in the deep biosphere revealed by extreme burrow depths in ancient sediments.

Science.gov (United States)

Cobain, S L; Hodgson, D M; Peakall, J; Wignall, P B; Cobain, M R D

2018-01-10

Macrofauna is known to inhabit the top few 10s cm of marine sediments, with rare burrows up to two metres below the seabed. Here, we provide evidence from deep-water Permian strata for a previously unrecognised habitat up to at least 8 metres below the sediment-water interface. Infaunal organisms exploited networks of forcibly injected sand below the seabed, forming living traces and reworking sediment. This is the first record that shows sediment injections are responsible for hosting macrofaunal life metres below the contemporaneous seabed. In addition, given the widespread occurrence of thick sandy successions that accumulate in deep-water settings, macrofauna living in the deep biosphere are likely much more prevalent than considered previously. These findings should influence future sampling strategies to better constrain the depth range of infaunal animals living in modern deep-sea sands. One Sentence Summary: The living depth of infaunal macrofauna is shown to reach at least 8 metres in new habitats associated with sand injections.

Sediment and Nutrient Sources as well as Interspecific Competition Control Growth of 2 Common Species of Coral Reef Macroalgae

Science.gov (United States)

Moore, T.; Fong, P.; Cuker, B.

2016-02-01

Aquatic communities worldwide are increasingly subjected to multiple anthropogenic stressors that often result in shifts in structure and function. On coral reefs, human impacts have been associated with phase-shifts from coral to algal domination. We hypothesized that the proliferation of these algal communities, especially on fringing reefs, may be facilitated by human alterations in nutrient enrichment and input of sediments from developed watersheds, which may also influence competitive outcomes among dominant algal species. To evaluate how changes in these abiotic stressors as well as competition may affect the growth of 2 common species of calcifying coral reef algae, Galaxaura fasciculata and Padina boryana, we conducted 3 separate 2 factor mesocosm experiments modeling fringing reefs in Moorea, French Polynesia. In the first experiment, we varied sediment source (marine vs. terrestrial) and water column nutrients (ambient vs. enriched) for each species separately and measured growth after 7 days. While both algae grew faster in enriched compared to ambient nutrients, P. boryana performed best with marine sediment (+27% change in biomass) and G. fasciculata with terrestrial sediment (+14% change in biomass). Next, we varied sediment source (as above) as well as sediment nutrients (ambient/enriched) for each species. While P. boryana lost 44% biomass in the eutrophic terrestrial sediment treatment, G. fasciculata performed the best and gained 19% biomass. Finally, we varied competition (alone/together) and terrestrial sediment nutrients (ambient/enriched). Over the 7 day period, P. boryana lost 64% biomass when in competition with G. fasciculata in the enriched treatment while G. fasciculata gained 38% biomass when in competition with P. boryana in the ambient treatment. These results indicate that, while growth of both species of macroalgae was regulated by nutrients, sediments, and competition, each responded uniquely to these controlling factors.

Biodiversity of a wreck from the Belgian Continental Shelf: monitoring using scientific diving: preliminary results

OpenAIRE

Massin, Cl.; Norro, A.; Mallefet, J.

2002-01-01

Scientific diving from aboard the r/v Belgica has been employed to carry out a preliminary study of the macrofauna living on a wreck (the Birkenfels) located on the Belgian Continental Shelf (BCS). The study revealed an extremely rich sessile and slow moving fauna (at least 40 species), 3 jellyfish species and 8 fish species. The presence of at least 51 species represents a biodiversity of macrofauna on the wreck that is much higher than that found in nearly all known surrounding soft bottorn...

Plasticity in feeding selectivity and trophic structure of kelp forest associated fishes from northern Chile Plasticidad en la selección de alimento y estructura trófica de los peces asociados a bosques de macroalgas pardas del norte de Chile

Directory of Open Access Journals (Sweden)

ALEJANDRO PÉREZ-MATUS

2012-03-01

alimentación, consumiendo directamente una fracción de los componentes del hábitat circundante. El propio hábitat, a su vez, puede determinar la conducta de forrajeo y los tipos de alimentación de sus depredadores. Para investigar la relación entre la disponibilidad de alimento y la composición de la dieta de los peces asociados a hábitat dominados por macroalgas pardas, se estimó la abundancia de las presas potenciales tanto especies sésiles como móviles y se comparó con la dieta de las especies de los peces en cuatro diferentes sitios de la costa del norte de Chile. Se determinó la dieta de los peces y su plasticidad alimentaria mediante la comparación entre la disponibilidad de presas con los ítemes presentes en los estómagos de los peces que fueron capturados por de red de enmalle y arpón de mano. Además se calculó el índice de selectividad alfa de Manly y el grado de sobreposición de la dieta de los peces costeros. Los resultados muestran que la utilización de las presas por los depredadores es afectada principalmente por la disponibilidad de presas potenciales. La mayoría de los peces asociados a las macroalgas difieren en su dieta en consonancia con la disponibilidad de los recursos a escalas locales, con la excepción de dos especies carnívoras tales como Pinguipes chilensis (Valenciennes, 1883 y Paralabrax humeralis (Cuvier & Valenciennes, 1828, cuya dieta no cambió entre los sitios estudiados. Las diferencias en la dieta de las especies son explicadas por los cambios en los recursos bentónicos que varían entre los sitios de estudio. Once de las 12 especies de peces asociados a los bosques de macroalgas pardas mostraron algún grado de selectividad de presas de origen bentónico. Se concluye que la habilidad de los peces de cambiar sus preferencias de alimentación y, por tanto, la partición de los recursos bentónicos puede obedecer a las adaptaciones para coexistir en un ambiente dinámico como aquel dominado por bosques de macroalgas

Do cues matter? Highly inductive settlement cues don't ensure high post-settlement survival in sea urchin aquaculture.

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Benjamin Mos

Full Text Available Increasing settlement and post-settlement survival during the critical transition from planktonic larvae to benthic juveniles will increase efficiency for sea urchin aquaculture. This study investigated the effects of temperature and settlement cues on the settlement and post-settlement survival of the sea urchin Tripneustes gratilla during this phase. The current commercial methodology, which utilises natural biofilm settlement plates, was tested and resulted in low settlement (90% than a natural biofilm (∼25%. The addition of macroalgae-conditioned seawater to natural biofilm significantly increased settlement rates (>85%. Mixed consortia and single strains of bacteria isolated from macroalgae, biofilms and adult conspecifics all induced significant settlement, but at significantly lower rates than macroalgae. No evidence was found that higher rates of settlement to bacteria on macroalgae were generated by a cofactor from the macroalgae. Age of bacterial cultures, culturing bacteria on solid and liquid media and concentration of nutrients in cultures had little effect on settlement rates. Finally, macroalgae-conditioned seawater combined with natural biofilm settlement plates induced significantly higher settlement than to the biofilm plates alone in a commercial scale trial. However, high post-settlement mortality resulted in equivalent survival between treatments after 25 days. This study highlights that settlement studies should extend to post-settlement survival, which remains poor for T. gratilla and is a significant obstacle to increasing efficiency for aquaculture.

Positive and negative effects of habitat-forming algae on survival, growth and intra-specific competition of limpets.

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Ezequiel M Marzinelli

Full Text Available Understanding the effects of environmental change on the distribution and abundance of strongly interacting organisms, such as intertidal macroalgae and their grazers, needs a thorough knowledge of their underpinning ecological relationships. Control of grazer-plant interactions is bi-directional on northwestern European coasts: grazing by limpets structures populations of macroalgae, while macroalgae provide habitat and food for limpets. Scottish shores dominated by the macroalga Fucus vesiculosus support lower densities and larger sizes of limpets Patella vulgata than shores with less Fucus. These patterns may be due to differences in inter-size-class competitive interactions of limpets among shores with different covers of Fucus. To examine this model, densities of small and large limpets were manipulated in plots with and without Fucus. Amounts of biofilm were measured in each plot. The presence of Fucus increased survival but hindered growth of small (15 mm TL limpets, which were negatively affected by the presence of large limpets (31 mm TL. In contrast, large limpets were not affected by the presence of Fucus or of small limpets. This suggests the occurrence of asymmetric inter-size-class competition, which was influenced by the presence of macroalgae. Macroalgae and increased densities of limpets did not influence amounts of biofilm. Our findings highlight the role of interactions among organisms in generating ecological responses to environmental change.

Assessing the herbivore role of the sea-urchin Echinometra viridis: Keys to determine the structure of communities in disturbed coral reefs.

Science.gov (United States)

Sangil, Carlos; Guzman, Hector M

2016-09-01

Echinometra viridis previously was considered a cryptic species unable to control the development and growth of macroalgae on coral reefs. Its role as a herbivore was seen as minor compared to other grazers present on the reef. However, the present disturbed state of some reefs has highlighted the role played by this sea-urchin. Combining field data with experiments on the Caribbean coast of Panama, we demonstrate that the current community organization on disturbed coral reefs in the Mesoamerican Caribbean is largely due to the action of E. viridis. It is the most abundant sea-urchin species, together with two others (Diadema antillarum and Echinometra lucunter). Field data also indicate that the relationship between its density and the abundance of macroalgae is stronger and it is more negative in impact than those of the other two. However, the niche this urchin exploits most efficiently is confined to leeward reefs with low levels of sedimentation. Outside these habitats, their populations are not decisive in controlling macroalgal growth. Grazing experiments showed that E. viridis consumes more fresh macroalgae per day and per weight of sea-urchin, and is a more effective grazer than D. antillarum or E. lucunter. E. viridis showed food preferences for early-successional turf macroalgae (Acanthophora spicifera), avoiding the less palatable late-successional and fleshy macroalgae (Lobophora variegata, Halimeda opuntia). However, it becomes a generalist herbivore feeding on all varieties of macroalgae when resources are scarce. H. opuntia is the macroalga that most resists E. viridis activity, which may explain its wide distribution. Copyright © 2016 Elsevier Ltd. All rights reserved.

Photosystem I shows a higher tolerance to sorbitol-induced osmotic stress than photosystem II in the intertidal macro-algae Ulva prolifera (Chlorophyta).

Science.gov (United States)

Gao, Shan; Zheng, Zhenbing; Gu, Wenhui; Xie, Xiujun; Huan, Li; Pan, Guanghua; Wang, Guangce

2014-10-01

The photosynthetic performance of the desiccation-tolerant, intertidal macro-algae Ulva prolifera was significantly affected by sorbitol-induced osmotic stress. Our results showed that photosynthetic activity decreased significantly with increases in sorbitol concentration. Although the partial activity of both photosystem I (PS I) and photosystem II (PS II) was able to recover after 30 min of rehydration, the activity of PS II decreased more rapidly than PS I. At 4 M sorbitol concentration, the activity of PS II was almost 0 while that of PS I was still at about one third of normal levels. Following prolonged treatment with 1 and 2 M sorbitol, the activity of PS I and PS II decreased slowly, suggesting that the effects of moderate concentrations of sorbitol on PS I and PS II were gradual. Interestingly, an increase in non-photochemical quenching occurred under these conditions in response to moderate osmotic stress, whereas it declined significantly under severe osmotic stress. These results suggest that photoprotection in U. prolifera could also be induced by moderate osmotic stress. In addition, the oxidation of PS I was significantly affected by osmotic stress. P700(+) in the thalli treated with high concentrations of sorbitol could still be reduced, as PS II was inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), but it could not be fully oxidized. This observation may be caused by the higher quantum yield of non-photochemical energy dissipation in PS I due to acceptor-side limitation (Y(NA)) during rehydration in seawater containing DCMU. © 2014 Scandinavian Plant Physiology Society.

Increased iron availability resulting from increased CO2 enhances carbon and nitrogen metabolism in the economical marine red macroalga Pyropia haitanensis (Rhodophyta).

Science.gov (United States)

Chen, Binbin; Zou, Dinghui; Yang, Yufeng

2017-04-01

Ocean acidification caused by rising CO 2 is predicted to increase the concentrations of dissolved species of Fe(II) and Fe(III), leading to the enhanced photosynthetic carbon sequestration in some algal species. In this study, the carbon and nitrogen metabolism in responses to increased iron availability under two CO 2 levels (390 μL L -1 and 1000 μL L -1 ), were investigated in the maricultivated macroalga Pyropia haitanensis (Rhodophyta). The results showed that, elevated CO 2 increased soluble carbonhydrate (SC) contents, resulting from enhanced photosynthesis and photosynthetic pigment synthesis in this algae, but declined its soluble protein (SP) contents, resulting in increased ratio of SC/SP. This enhanced photosynthesis performance and carbon accumulation was more significant under iron enrichment condition in seawater, with higher iron uptake rate at high CO 2 level. As a key essential biogenic element for algae, Fe-replete functionally contributed to P. haitanensis photosynthesis. Increased SC fundamentally provided carbon skeletons for nitrogen assimilation. The significant increase of carbon and nitrogen assimilation finally contributed to enhanced growth in this alga. This was also intuitively reflected by respiration that provided energy for cellular metabolism and algal growth. We propose that, in the predicted scenario of rising atmospheric CO 2 , P. haitanensis is capable to adjust its physiology by increasing its carbon and nitrogen metabolism to acclimate the acidified seawater, at the background of global climate change and simultaneously increased iron concentration due to decreased pH levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bioremediation of Aluminium from the Waste Water of a Conventional Water Treatment Plant Using the Freshwater Macroalga Oedogonium

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David A. Roberts

2018-05-01

Full Text Available Conventional water treatment processes use aluminium sulphate (alum as a coagulant in the production of potable water. While alum is an inexpensive and reliable means of treating water, the process generates waste water containing dissolved Al. This waste water is primarily dealt with via on-site retention. In this study we investigate the cultivation of the freshwater macroalga Oedogonium as a means to sequester dissolved Al from waste water from a conventional water treatment plant. Furthermore, we examine the use of CO2 to manipulate the pH of cultivation as a means of enhancing the sequestration of Al by either increasing the productivity of Oedogonium or increasing the bioavailability of Al in the waste water. The relative bioavailability of Al under conditions of CO2 and no-CO2 provision was contrasted by comparing Al uptake by Diffusive Gradients in Thin Films (DGTs. Oedogonium was able to grow rapidly in the waste water (12 g dry weight m−2 day−1 while consistently sequestering Al. The Oedogonium-treated waste water had a sufficiently low Al concentration that it could be used in unrestricted irrigation in the surrounding region. When CO2 was added to the waste water containing concentrations of Al up to 8 mg L−1, there was a slight increase (~10% in the rate of sequestration of Al by Oedogonium relative to waste water not receiving CO2. This was due to two concurrent processes. The provision of CO2 increased the productivity of Oedogonium by 15% and the bioavailability of Al by up to 200%, as measured by the DGTs. Despite this strong effect of CO2 on Al bioavailability, the increase in Al sequestration by Oedogonium when CO2 was provided was modest (~10%. Al was sequestered by Oedogonium to concentrations below permissible limits for discharge without the need for the addition CO2. The cultivation of Oedogonium in waste water from conventional treatments plants can simultaneously treat waste water for re-use and provide a biomass

Seaweeds as Preventive Agents for Cardiovascular Diseases: From Nutrients to Functional Foods

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Susana M. Cardoso

2015-11-01

Full Text Available Being naturally enriched in key nutrients and in various health-promoting compounds, seaweeds represent promising candidates for the design of functional foods. Soluble dietary fibers, peptides, phlorotannins, lipids and minerals are macroalgae’s major compounds that can hold potential in high-value food products derived from macroalgae, including those directed to the cardiovascular-health promotion. This manuscript revises available reported data focusing the role of diet supplementation of macroalgae, or extracts enriched in bioactive compounds from macroalgae origin, in targeting modifiable markers of cardiovascular diseases (CVDs, like dyslipidemia, oxidative stress, vascular inflammation, hypertension, hypercoagulability and activation of the sympathetic and renin-angiotensin systems, among others. At last, the review also describes several products that have been formulated with the use of whole macroalgae or extracts, along with their claimed cardiovascular-associated benefits.

Effects of heavy metals and light levels on the biosynthesis of carotenoids and fatty acids in the macroalgae Gracilaria tenuistipitata (var. liui Zhang & Xia

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Ernani Pinto

2011-04-01

Full Text Available We present here the effect of heavy metals and of different light intensities on the biosynthesis of fatty acids and pigments in the macroalga Gracilaria tenuistipitata (var. liui Zhang & Xia. In order to verify the fatty acid content, gas chromatography with flame ionization detection (GC-FID was employed. Pigments (major carotenoids and chlorophyl-a were monitored by liquid chromatography with diode array detection (HPLC-DAD. Cultures of G. tenuistipitata were exposed to cadmium (Cd2+, 200 ppb and copper (Cu2+, 200 ppb, as well as to different light conditions (low light: 100 µmol.photons.m-2.s-1, or high light: 1000 µmol.photons.m-2.s-1. Cd2+ and Cu2+ increased the saturated and monounsaturated fatty acid content [14:0, 16:0, 18:0, 18:1 (n-7 and 18:1 (n-9] and all major pigments (violaxanthin, antheraxanthin, lutein, zeaxanthin, chlorophyll-a and β-carotene. Both heavy metals decreased the levels of polyunsaturated fatty acids (PUFA [18:2 (n-6, 18:3 (n-6, 18:5 (n-4, 20:4 (n-6, 20:5 (n-3, 22:6 (n-3]. G. tenuistipitata cultures were exposed to high light intensity for five days and no statistically significant differences were observed in the content of fatty acids. On the other hand, the levels of pigments rose markedly for chlorophyll-a and all of the carotenoids studied.

A novel marine algal toxicity bioassay based on sporulation inhibition in the green macroalga Ulva pertusa (Chlorophyta)

International Nuclear Information System (INIS)

Han, Taejun; Choi, Gye-Woon

2005-01-01

A 5-day aquatic toxicity test based on sporulation inhibition of the green macroalga Ulva pertusa Kjellman has been developed. Optimal test conditions determined for photon irradiance, salinity and temperature were 60-200 μmol photons m -2 s -1 , 25-35%o and 15-20 deg C, respectively. Tests were conducted by exposing U. pertusa thallus disks to a reference toxicant (sodium dodecyl sulfate; SDS), metals (Cd 2+ , Cu 2+ , Zn 2+ , Pb 2+ ) and elutriates of sludge collected from nine different locations. The EC 50 values for SDS was 5.35 mg L -1 . When four heavy metals were assayed, the NOECs were highest for lead (0.625 mg L -1 ) and lowest for copper (0.031 mg L -1 ). The EC 50 values showed the following toxicity rankings: Cu 2+ (0.061 mg L -1 ) > Cd 2+ (0.326 mg L -1 ) > Zn 2+ (0.738 mg L -1 ) > Pb 2+ (0.877 mg L -1 ). The bioassay indicated also that the sporulation endpoint could be a sensitive indicator of toxicity effects of elutriates of sludge as reflected from the NOEC values equal to or lower than the lowest concentration employed (6.25%). Sporulation was significantly inhibitied in all elutriates with the greatest and least effects observed in elutriates of sludge from industrial waste (EC 50 6.78%) and filtration bed (EC 50 15.0%), respectively. The results of the Spearman rank correlation analysis for EC 50 data versus the concentrations of toxicants in the sludge presented a significant correlation between toxicity and four heavy metals (Cd 2+ , Cu 2+ , Pb 2+ , Zn 2+ ). Introduction of the concept of toxicity unit (TU) showed that these metals were the main cause of toxicity in elutriates of at least four out of nine sludge samples. Members of the order Ulvales show a wide geographic distribution and have similar reproductive characteristics, thus making it possible to apply the present test method to other algae of this taxa, elsewhere. This novel method will be a useful tool for assessing the aquatic toxicity of a wide range of toxicants, once the

Diurnal changes of photosynthetic quantum yield in the intertidal macroalga Sargassum thunbergii under simulated tidal emersion conditions

Science.gov (United States)

Yu, Yong Qiang; Zhang, Quan Sheng; Tang, Yong Zheng; Li, Xue Meng; Liu, Hong Liang; Li, Li Xia

2013-07-01

In this study, a three-way factorial experimental design was used to investigate the diurnal changes of photosynthetic activity of the intertidal macroalga Sargassum thunbergii in response to temperature, tidal pattern and desiccation during a simulated diurnal light cycle. The maximum (Fv/Fm) and effective (ΦPSII) quantum yields of photosystem II (PSII) were estimated by chlorophyll fluorescence using a pulse amplitude modulated fluorometer. Results showed that this species exhibited sun-adapted characteristics, as evidenced by the daily variation of Fv/Fm and ΦPSII. Both yield values decreased with increasing irradiance towards noon and recovered rapidly in the afternoon suggesting a dynamic photoinhibition. The photosynthetic quantum yield of S. thunbergii thalli varied significantly with temperature, tidal pattern and desiccation. Thalli were more susceptible to light-induced damage at high temperature of 25 °C and showed complete recovery of photosynthetic activity only when exposed to 8 °C. In contrast with the mid-morning low tide period, although there was an initial increase in photosynthetic yield during emersion, thalli showed a greater degree of decline at the end of emersion and remained less able to recover when low tide occurred at mid-afternoon. Short-term air exposure of 2 h did not significantly influence the photosynthesis. However, when exposed to moderate conditions (4 h desiccation at 15 °C or 6 h desiccation at 8 °C), a significant inhibition of photosynthesis was followed by partial or complete recovery upon re-immersion in late afternoon. Only extreme conditions (4 h desiccation at 25 °C or 6 h desiccation at 15 °C or 25 °C) resulted in the complete inhibition, with little indication of recovery until the following morning, implying the occurrence of chronic PSII damage. Based on the magnitude of effect, desiccation was the predominant negative factor affecting the photosynthesis under the simulated daytime irradiance period. These

Benthic assemblages of mega epifauna on the Oregon continental margin

Science.gov (United States)

Hemery, Lenaïg G.; Henkel, Sarah K.; Cochrane, Guy R.

2018-01-01

Environmental assessment studies are usually required by a country's administration before issuing permits for any industrial activities. One of the goals of such environmental assessment studies is to highlight species assemblages and habitat composition that could make the targeted area unique. A section of the Oregon continental slope that had not been previously explored was targeted for the deployment of floating wind turbines. We carried out an underwater video survey, using a towed camera sled, to describe its benthic assemblages. Organisms were identified to the lowest taxonomic level possible and assemblages described related to the nature of the seafloor and the depth. We highlighted six invertebrate assemblages and three fish assemblages. For the invertebrates within flat soft sediments areas we defined three different assemblages based on primarily depth: a broad mid-depth (98–315 m) assemblage dominated by red octopus, sea pens and pink shrimps; a narrower mid-depth (250–270 m) assemblage dominated by box crabs and various other invertebrates; and a deeper (310–600 m) assemblage dominated by sea urchins, sea anemones, various snails and zoroasterid sea stars. The invertebrates on mixed sediments also were divided into three different assemblages: a shallow (~100 m deep) assemblage dominated by plumose sea anemones, broad mid-depth (170–370 m) assemblage dominated by sea cucumbers and various other invertebrates; and, again, a narrower mid-depth (230–270 m) assemblage, dominated by crinoids and encrusting invertebrates. For the fish, we identified a rockfish assemblage on coarse mixed sediments at 170–370 m and another fish assemblage on smaller mixed sediments within that depth range (250–370 m) dominated by thornyheads, poachers and flatfishes; and we identified a wide depth-range (98–600 m) fish assemblage on flat soft sediments dominated by flatfishes, eelpouts and thornyheads. Three of these assemblages (the two broad fish assemblages and the deep flat soft sediments invertebrate assemblage) seem to represent deeper examples of assemblages already known on the Oregon continental shelf, especially on soft sediments, while the assemblages in the pockmarks habitat (the narrower depth ranges) might be unique to the area. This diversity of assemblages in a relatively small section of the Oregon continental upper slope and shelf shows the importance of environmental assessment studies in helping limit future impacts of industrial activities on benthic communities.

Benthic assemblages of mega epifauna on the Oregon continental margin

Science.gov (United States)

Hemery, Lenaïg G.; Henkel, Sarah K.; Cochrane, Guy R.

2018-05-01

Environmental assessment studies are usually required by a country's administration before issuing permits for any industrial activities. One of the goals of such environmental assessment studies is to highlight species assemblages and habitat composition that could make the targeted area unique. A section of the Oregon continental slope that had not been previously explored was targeted for the deployment of floating wind turbines. We carried out an underwater video survey, using a towed camera sled, to describe its benthic assemblages. Organisms were identified to the lowest taxonomic level possible and assemblages described related to the nature of the seafloor and the depth. We highlighted six invertebrate assemblages and three fish assemblages. For the invertebrates within flat soft sediments areas we defined three different assemblages based on primarily depth: a broad mid-depth (98-315 m) assemblage dominated by red octopus, sea pens and pink shrimps; a narrower mid-depth (250-270 m) assemblage dominated by box crabs and various other invertebrates; and a deeper (310-600 m) assemblage dominated by sea urchins, sea anemones, various snails and zoroasterid sea stars. The invertebrates on mixed sediments also were divided into three different assemblages: a shallow ( 100 m deep) assemblage dominated by plumose sea anemones, broad mid-depth (170-370 m) assemblage dominated by sea cucumbers and various other invertebrates; and, again, a narrower mid-depth (230-270 m) assemblage, dominated by crinoids and encrusting invertebrates. For the fish, we identified a rockfish assemblage on coarse mixed sediments at 170-370 m and another fish assemblage on smaller mixed sediments within that depth range (250-370 m) dominated by thornyheads, poachers and flatfishes; and we identified a wide depth-range (98-600 m) fish assemblage on flat soft sediments dominated by flatfishes, eelpouts and thornyheads. Three of these assemblages (the two broad fish assemblages and the deep flat soft sediments invertebrate assemblage) seem to represent deeper examples of assemblages already known on the Oregon continental shelf, especially on soft sediments, while the assemblages in the pockmarks habitat (the narrower depth ranges) might be unique to the area. This diversity of assemblages in a relatively small section of the Oregon continental upper slope and shelf shows the importance of environmental assessment studies in helping limit future impacts of industrial activities on benthic communities.

Species effects on ecosystem processes are modified by faunal responses to habitat composition.

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Bulling, Mark T; Solan, Martin; Dyson, Kirstie E; Hernandez-Milian, Gema; Luque, Patricia; Pierce, Graham J; Raffaelli, Dave; Paterson, David M; White, Piran C L

2008-12-01

Heterogeneity is a well-recognized feature of natural environments, and the spatial distribution and movement of individual species is primarily driven by resource requirements. In laboratory experiments designed to explore how different species drive ecosystem processes, such as nutrient release, habitat heterogeneity is often seen as something which must be rigorously controlled for. Most small experimental systems are therefore spatially homogeneous, and the link between environmental heterogeneity and its effects on the redistribution of individuals and species, and on ecosystem processes, has not been fully explored. In this paper, we used a mesocosm system to investigate the relationship between habitat composition, species movement and sediment nutrient release for each of four functionally contrasting species of marine benthic invertebrate macrofauna. For each species, various habitat configurations were generated by selectively enriching patches of sediment with macroalgae, a natural source of spatial variability in intertidal mudflats. We found that the direction and extent of faunal movement between patches differs with species identity, density and habitat composition. Combinations of these factors lead to concomitant changes in nutrient release, such that habitat composition effects are modified by species identity (in the case of NH4-N) and by species density (in the case of PO4-P). It is clear that failure to accommodate natural patterns of spatial heterogeneity in such studies may result in an incomplete understanding of system behaviour. This will be particularly important for future experiments designed to explore the effects of species richness on ecosystem processes, where the complex interactions reported here for single species may be compounded when species are brought together in multi-species combinations.

Liquid biofuels from blue biomass

DEFF Research Database (Denmark)

Kádár, Zsófia; Jensen, Annette Eva; Bangsø Nielsen, Henrik

2011-01-01

Marine (blue) biomasses, such as macroalgaes, represent a huge unexploited amount of biomass. With their various chemical compositions, macroalgaes can be a potential substrate for food, feed, biomaterials, pharmaceuticals, health care products and also for bioenergy. Algae use seawater as a growth...... medium, light as energy source and they capture CO2 for the synthesis of new organic material, thus can grow on non-agricultural land, without increasing food prices, or using fresh water. Due to all these advantages in addition to very high biomass yield with high carbohydrate content, macroalgaes can...

The effect of re-dissolution solvents and HPLC columns on the analysis of mycosporine-like amino acids in the eulittoral macroalgae Prasiola crispa and Porphyra umbilicalis

Science.gov (United States)

Karsten, Ulf; Escoubeyrou, Karine; Charles, François

2009-09-01

Many macroalgal species that are regularly exposed to high solar radiation such as the eulittoral green alga Prasiola crispa and the red alga Porphyra umbilicalis synthesize and accumulate high concentrations of mycosporine-like amino acids (MAAs) as UV-sunscreen compounds. These substances are typically extracted with a widely used standard protocol following quantification by various high performance liquid chromatography (HPLC) techniques. However, further preparation steps prior to HPLC analysis as well as different HPLC column types have not been systematically checked regarding separation quality and reproducibility. Therefore pure methanol, distilled water and HPLC eluent were evaluated as re-dissolution solvent for dried Prasiola and Porphyra extracts, which were subsequently analyzed on three reversed-phase C8 and C18 HPLC columns. The data indicate that distilled water and the HPLC eluent gave almost identical peak patterns and MAA contents on the C8 and C18 columns. In contrast, the application of the widely used methanol led to double peaks or even the loss of specific peaks as well as to a strong decline in total MAA amounts ranging from about 35% of the maximum in P. crispa to 80% of the maximum in P. umbilicalis. Consequently, methanol should be avoided as re-dissolution solvent for the HPLC sample preparation. An improved protocol for the MAA analysis in macroalgae in combination with a reliable C18 column is suggested.

Antimicrobial Activities of Bacteria Associated with the Brown Alga

NARCIS (Netherlands)

Ismail, A.; Ktari, L.; Bolhuis, H.; Ahmed, M.; Boudabbous, A.; Stal, L.J.; Cretoiu, M.S.; El Bour, M.

2016-01-01

Macroalgae belonging to the genus Padina are known to produce antibacterial compounds that may inhibit growth of human- and animal pathogens. Hitherto, it was unclear whether this antibacterial activity is produced by the macroalga itself or by secondary metabolite producing epiphytic bacteria. Here

A relative contribution of carbon from green tide algae Cladophora glomerata and Ulva intestinalis in the coastal food webs in the Neva Estuary (Baltic Sea).

Science.gov (United States)

Golubkov, Sergey M; Berezina, Nadezhda A; Gubelit, Yulia I; Demchuk, Anna S; Golubkov, Mikhail S; Tiunov, Alexei V

2018-01-01

We analyzed stable isotope composition of carbon and nitrogen of suspended organic matter (seston) and tissues of macroalgae, macroinvertebrates and fish from the coastal area of the highly eutrophic Neva Estuary to test a hypothesis that organic carbon of macroalgae Cladophora glomerata and Ulva intestinalis produced during green tides may be among primary sources supporting coastal food webs. The Stable Isotope Bayesian mixing model (SIAR) showed that consumers poorly use organic carbon produced by macroalgae. According to the results of SIAR modeling, benthic macroinvertebrates and fish mostly rely on pelagic derived carbon as a basal resource for their production. Only some species of macroinvertebrates consumed macroalgae. Fish used this resource directly consuming zooplankton or indirectly via benthic macroinvertebrates. This was consistent with the results of the gut content analysis, which revealed a high proportion of zooplankton in the guts of non-predatory fish. Copyright © 2017. Published by Elsevier Ltd.

Laminaria digitata as potential carbon source in heterotrophic microalgae cultivation for the production of fish feed supplement

DEFF Research Database (Denmark)

D'Este, Martina; Alvarado-Morales, Merlin; Angelidaki, Irini

2017-01-01

A novel concept using the macroalgae Laminaria digitata as substrate to grow heterotrophically microalgae species to be used as fish feed supplement is investigated in the present study. Enzymatic hydrolysis of the macroalgae was performed to release the sugars present in the biomass. The hydroly......A novel concept using the macroalgae Laminaria digitata as substrate to grow heterotrophically microalgae species to be used as fish feed supplement is investigated in the present study. Enzymatic hydrolysis of the macroalgae was performed to release the sugars present in the biomass...... was selected for further cultivation in batch reactors and its protein content and amino acid composition were measured. At the end of the process the biomass production reached 10.68 ± 1.33 g L− 1with a total protein accumulation of 41.77 ± 1.82% (dry weight basis) and a protein yield of 0.17 ± 0.06. Moreover...

Keanekaragaman dan Kerapatan Rumput Laut Alami Perairan Pulau Serangan Denpasar Bali

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Ni Desak Putu Dita Herlinawati

2017-08-01

Full Text Available Serangan Island was a costal area located in the Serangan village, South Denpasar district, near with Sanur and Nusa Dua tourism area. Serangan beach has a biodiversity such as natural macroalgae. This study was conducted in January 2017 at the seaweed cultivation area with the aims of research were to know the variety and density of macroalgae. The method used was a 1x1 m quadrat transect. Sampling was carried out during low tide. Macroalgae found in the area, consist of 12 species namely Ulva lactuca, Chaetomorpha linum. Chaetomorpha aera, Padina australis, Sargassum fluitans, Turbinaria ornate, Gelidium sp., Hypnea cornuta, Hypnea spicifera, Gracilaria salicornia, Acanthophora spicifera, Halimeda opuntia. Those species were belonging to 3 divisi namely Chlorophyta, Phaeophyta, Rhodophyta. The highest density of macroalgae was Padina australis while the lowest density was Chaetomorpha linum. Type of dominated macroalgae was from a group of Phaeophyta (brown algae with highest dominance from the species of Padina australis. Water quality namely acidity (pH was in the range of 7.54 to 7.75, salinity of 31.33-32.00 ppt, the water temperature was 26.50-27.30? C, which all was categorized as the optimal parameters for the growth of macroalgae. Assosiation of biota found were 9 species namely fish of larva, Cypraea lynx (Molusca, Emerita sp., Halodule sp., Synapta maculate, Enhalus acoroides, Cymodocea serrulata, Hermit crab, Ophiuroidea sp. The conditions coastal waters substrate was varied from white sand stone type to stony type by coral pieces.

Has Phytodetritus Processing by an Abyssal Soft-Sediment Community Recovered 26 Years after an Experimental Disturbance?

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Tanja Stratmann

2018-02-01

Full Text Available The potential harvest of polymetallic nodules will heavily impact the abyssal, soft sediment ecosystem by removing sediment, hard substrate, and associated fauna inside mined areas. It is therefore important to know whether the ecosystem can recover from this disturbance and if so at which rate. The first objective of this study was to measure recovery of phytodetritus processing by the benthic food web from a sediment disturbance experiment in 1989. The second objective was to determine the role of holothurians in the uptake of fresh phytodetritus by the benthic food web. To meet both objectives, large benthic incubation chambers (CUBEs; 50 × 50 × 50 cm were deployed inside plow tracks (with and without holothurian presence and at a reference site (holothurian presence, only at 4100 m water depth. Shortly after deployment, 13C- and 15N-labeled phytodetritus was injected in the incubation chambers and during the subsequent 3-day incubation period, water samples were taken five times to measure the production of 13C-dissolved inorganic carbon over time. At the end of the incubation, holothurians and sediment samples were taken to determine biomass, densities and incorporation of 13C and 15N into bacteria, nematodes, macrofauna, and holothurians. For the first objective, the results showed that biomass of bacteria, nematodes and macrofauna did not differ between reference sites and plow track sites when holothurians were present. Additionally, meiofauna and macrofauna taxonomic composition was not significantly different between the sites. In contrast, total 13C uptake by bacteria, nematodes and holothurians was significantly lower at plow track sites compared to reference sites, though the number of replicates was low. This result suggests that important ecosystem functions such as organic matter processing have not fully recovered from the disturbance that occurred 26 years prior to our study. For the second objective, the analysis indicated

[Community structure of soil fauna in Eucalyptus grandis plantations at different slope locations].

Science.gov (United States)

Zhao, Yu; Zhong, Yu; Zhang, Jian; Yang, Wan-qin

2010-09-01

To understand the effects of slope location on the community structure of soil fauna in Eucalyptus grandis plantation, an investigation was made on the soil fauna in 3 E. grandis plantations at different slope locations in the hilly area of Sichuan Province from January to October 2009. A total of 39,2762 individuals were observed, belonging to 146 groups, 7 phyla, 16 classes, and 31 orders. The community composition, trophic group, diversity, and seasonal dynamics of soil fauna in the plantations all varied with slope. The abundance of macro-fauna, xeric meso- and micro-fauna, saprophagous macro-fauna, and omnivorous xeric meso- and micro-fauna increased with the decrease of slope, indicating that soil fauna had sensitive responses to the soil environmental factors affected by slope. Significant differences in the diversity of soil saprophagous macro-fauna and hygrophilous meso- and micro-fauna were observed at different slope locations, suggesting that these two faunal groups could be used as the indicators of the habitat heterogeneity of E. grandis plantations at different slope. Overall, slope location had definite effects on the community structure and distribution of soil fauna in the E. grandis plantations, but the effects were not statistically significant.

Comparative cradle-to-grave life cycle assessment of biogas production from marine algae and cattle manure biorefineries.

Science.gov (United States)

Giwa, Adewale

2017-11-01

The environmental impacts resulting from the cradle-to-grave life cycles of Enteromorpha prolifera macroalgae and cattle manure biorefineries are assessed and compared. Sensitivity analysis is carried out to evaluate the response of the impacts to changes in biogas application by using Simapro 7.3.3. Three scenarios are considered in the biorefineries. In the first and second scenarios, the biogas produced is considered to be used for electricity production and transportation, respectively. In the third scenario, the biogas is considered to be recycled back to the systems. Process energy requirements and transportation of inputs contribute the largest share of the overall impacts. The cattle manure biorefinery is slightly more eco-friendly than the macroalgae biorefinery in Scenarios 1 and 2 because it requires more eco-friendly inputs. However, the macroalgae biorefinery becomes more eco-friendly than the cattle manure biorefinery in Scenario 3 because macroalgae require less energy and water for biogas production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Seagrass habitat complexity and macroinvertebrate abundance in Lakshadweep coral reef lagoons, Arabian Sea

Science.gov (United States)

Ansari, Z. A.; Rivonker, C. U.; Ramani, P.; Parulekar, A. H.

1991-09-01

Macrofauna of seagrass community in the five Lakshadweep atolls were studied and compared. The associated epifaunal and infaunal taxa comprising nine major taxonomic groups, showed significant differences in the total number of individuals (1041 8411 m-2) among sites and habitats. The density of macrofauna was directly related to mean macrophytic biomass (405 895 g wet wt. m-2). The fauna was dominated by epifaunal polychaetes, amphipods and isopods in the vegetated areas. When compared with the density of nearby unvegetated areasleft( {bar x = 815{text{m }}^{ - 2} } right), seagrass meadows harbour a denser and richer macroinvertebrate assemblageleft( {bar x = 4023{text{m }}^{ - 2} } right).

A novel marine algal toxicity bioassay based on sporulation inhibition in the green macroalga Ulva pertusa (Chlorophyta)

Energy Technology Data Exchange (ETDEWEB)

Han, Taejun [Division of Biology and Chemistry, University of Incheon, Incheon 402-749 (Korea, Republic of)]. E-mail: hanalgae@incheon.ac.kr; Choi, Gye-Woon [Department of Civil and Environmental System Engineering, University of Incheon, Incheon 402-749 (Korea, Republic of)

2005-11-10

A 5-day aquatic toxicity test based on sporulation inhibition of the green macroalga Ulva pertusa Kjellman has been developed. Optimal test conditions determined for photon irradiance, salinity and temperature were 60-200 {mu}mol photons m{sup -2} s{sup -1}, 25-35%o and 15-20 deg C, respectively. Tests were conducted by exposing U. pertusa thallus disks to a reference toxicant (sodium dodecyl sulfate; SDS), metals (Cd{sup 2+}, Cu{sup 2+}, Zn{sup 2+}, Pb{sup 2+}) and elutriates of sludge collected from nine different locations. The EC{sub 50} values for SDS was 5.35 mg L{sup -1}. When four heavy metals were assayed, the NOECs were highest for lead (0.625 mg L{sup -1}) and lowest for copper (0.031 mg L{sup -1}). The EC{sub 50} values showed the following toxicity rankings: Cu{sup 2+} (0.061 mg L{sup -1}) > Cd{sup 2+} (0.326 mg L{sup -1}) > Zn{sup 2+} (0.738 mg L{sup -1}) > Pb{sup 2+} (0.877 mg L{sup -1}). The bioassay indicated also that the sporulation endpoint could be a sensitive indicator of toxicity effects of elutriates of sludge as reflected from the NOEC values equal to or lower than the lowest concentration employed (6.25%). Sporulation was significantly inhibitied in all elutriates with the greatest and least effects observed in elutriates of sludge from industrial waste (EC{sub 50} 6.78%) and filtration bed (EC{sub 50} 15.0%), respectively. The results of the Spearman rank correlation analysis for EC{sub 50} data versus the concentrations of toxicants in the sludge presented a significant correlation between toxicity and four heavy metals (Cd{sup 2+}, Cu{sup 2+}, Pb{sup 2+}, Zn{sup 2+}). Introduction of the concept of toxicity unit (TU) showed that these metals were the main cause of toxicity in elutriates of at least four out of nine sludge samples. Members of the order Ulvales show a wide geographic distribution and have similar reproductive characteristics, thus making it possible to apply the present test method to other algae of this taxa, elsewhere

IDENTIFIKASI KEANEKARAGAMAN DAN POLA PENYEBARAN MAKROALGA DI DAERAH PASANG SURUT PANTAI PIDAKAN KABUPATEN PACITAN SEBAGAI SUMBER BELAJAR BIOLOGI

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Ilham Budi Setyawan

2015-03-01

Full Text Available This research aimed to find out variance, ecology parameter,variance index,and dispersion pattern of macroalgae existed in intertidal pidakan beach sub-district Pacitan Residence.The results of research in the area of tidal beach Pidakan on 90 plots was found in 1925 with 17 individual macro algae species originating from the third division Rhodophyta, Chlorophyta and Phaeophyta.Variance index of (H’ was high richness category and value (E was means community tend to flat. Index of Morisita (IM mean dispersion of all Macroalgae was clumped. As a complement to the results of the study are used as a learning module macroalgae for SMA/MA

Suivi DCE 2017 « macroalgues subtidales » dans la masse d’eau « côte basque » et « macroalgues intertidales » dans la masse d’eau de transition « Adour aval ».

OpenAIRE

De Casamajor, Marie-noelle; Lissardy, Muriel; Sanchez, Florence; Saguet, Cassandre

2017-01-01

This report describe sampling campaign 2017 related to data collection for WFD macroalgae indicators. The parameters concerned are "subtidal macroalgae" for coastal water body “Basque coast” and “intertidal macroalgae” for the transition water body “Adour aval”. The data treatment and the indicator calculation will be done in a second step.

Gene expression of corals in response to macroalgal competitors.

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Tonya L Shearer

Full Text Available As corals decline and macroalgae proliferate on coral reefs, coral-macroalgal competition becomes more frequent and ecologically important. Whether corals are damaged by these interactions depends on susceptibility of the coral and traits of macroalgal competitors. Investigating changes in gene expression of corals and their intracellular symbiotic algae, Symbiodinium, in response to contact with different macroalgae provides insight into the biological processes and cellular pathways affected by competition with macroalgae. We evaluated the gene expression profiles of coral and Symbiodinium genes from two confamilial corals, Acropora millepora and Montipora digitata, after 6 h and 48 h of contact with four common macroalgae that differ in their allelopathic potency to corals. Contacts with macroalgae affected different biological pathways in the more susceptible (A. millepora versus the more resistant (M. digitata coral. Genes of coral hosts and of their associated Symbiodinium also responded in species-specific and time-specific ways to each macroalga. Changes in number and expression intensity of affected genes were greater after 6 h compared to 48 h of contact and were greater following contact with Chlorodesmis fastigiata and Amphiroa crassa than following contact with Galaxaura filamentosa or Turbinaria conoides. We documented a divergence in transcriptional responses between two confamilial corals and their associated Symbiodinium, as well as a diversity of dynamic responses within each coral species with respect to the species of macroalgal competitor and the duration of exposure to that competitor. These responses included early initiation of immune processes by Montipora, which is more resistant to damage after long-term macroalgal contact. Activation of the immune response by corals that better resist algal competition is consistent with the hypothesis that some macroalgal effects on corals may be mediated by microbial pathogens.