TEMPERATURE RESPONSES AND DISTRIBUTION OF AUSTRALIAN SPECIES OF CLADOPHORA (CLADOPHORALES, CHLOROPHYTA)

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CAMBRIDGE, ML; BREEMAN, AM; VANDENHOEK, C

Temperature ranges for survival, growth and sporulation of isolates of 11 Cladophora species from Australia, as well as one isolate from Japan, were tested in constant temperature conditions from 0 to 35-degrees-C at 5-degrees-C intervals over 3 months. These ranges were compared with those

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.

Characteristic carotenoids in some phytobenthos species in the coastal area of the Adriatic Sea

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Bazyli Czeczuga

2014-01-01

Full Text Available The author investigated the presence of various carotcnoids in some phytobenthos species (20 species representative of Chlorophytn, Phaeophyta and Rhodophyta from the coast of the Adriatic Sea. The presence of following carotenoids has been determined 1 in Chlorophyta lycopene, α-, β-, γ- , ε-carotene, β-cryptoxanthin, lutein, lutein epoxide, zeaxanthin, antheraxanthin, neoxanthin, violaxanthin, siphonein and astaxanthin esier; 2 in Phorophyta: α-, β-, γ- , ε- carotene, zeaxanthin, antheraxanthin, diataxanthin, fucoxanthin, fucoxanthol, neoxanthin, violaxanthin and rhodoxanthin-like: 3 in Rhodophyta α-, β-, γ-carotene,α-, β-,cryptoxanthin, lutein lutein epoxide, zeaxanthin, anthcraxanthin, mutatoxanthin, fucoxanthin neoxanthin and violaxanthin The total carotenoid content ranged from 1.197 ( Cystoseira corniculata to 16 748 mg g-1 dry weight (Chaetomorpha aerea.

Community structure characteristics of phytoplankton in zhalong wetland, china

International Nuclear Information System (INIS)

Zhang, N.; Zang, S.S.

2015-01-01

In autumn 2010, the phytoplankton samples were collected in Zhalong Wetland. A total of 347 species belonging to 78 genera,6 phyla were identified, Chlorophyta and Bacillariophyta were dominated phytoplankton communities, including 143 species of Chlorophyta, 116 species of Bacillariophyta, 45 species of Cyanophyta, 39 species of Euglenophyta, 3 species of Pyrrophyta, 1 species of Chrysophyta. In the core area 66 genera, 222 species were identified, in the buffer area 63 genera, 210 species were identified, in the experiment area 63 genera, 167 species were identified. The dominant species in Zhalong Wetland included Cyclotella meneghiniana, Chlorella vulgaris, Trachelomonas volvocina, Nitzschia sp.. The average phytoplankton density was 12.13*10/sup 6/ in Zhalong Wetland, the phytoplankton density of Bacillariophyta was highest (32.82*10/sup 6/ ind L/sup -1/), and then Chlorophyta (23.73*10/sup 6/ ind L/sup -1/) and Cyanophyta (11.43*106 ind L-1), respectively. The results of cluster analysis showed that phytoplankton community structure could be divided into three types, and within-group similarities of phytoplankton community structure was not high, but inter-group non-similarity was high. Based on the species composition, phytoplankton density, phytoplankton pollution indicator, it suggested that Zhalong Wetland was mesotrophic state. (author)

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.

Marine algal flora of submerged Angria Bank (Arabian Sea)

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Untawale, A.G.; Reddy, C.R.K.; Ambiye, V.

Submerged Angria Bank was surveyed for the deep water marine algal flora. About 57 species were reported from this bank for the first time. Rhodophyta dominated (30 species) followed by Chlorophyta (18 species) and Phaeophyta (9 species). A few...

Tetraselmis indica (Chlorodendrophyceae, Chlorophyta), a new species isolated from salt pans in Goa, India

Digital Repository Service at National Institute of Oceanography (India)

Mani, A.; Anil, A.C; Leliaert, F.; Delany, J; Mesbahi, E.

is characterized by a distinct eyespot, rectangular nucleus, a large number of Golgi bodies, two types of flagellar pit hairs and a characteristic type of cell division. In nature, the species was found in a wide range of temperatures (48 degrees C down to 28...

A dichotomous species of Codium (Bryopsidales, Chlorophyta is colonizing northern Chile Una especie dicotómica de Codium (Bryopsidales, Chlorophyta está colonizando el norte de Chile

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ALEJANDRA GONZÁLEZ

2004-06-01

Full Text Available In late 2001 and early 2002, a dichotomous species of Codium appeared colonizing the low intertidal and shallow subtidal bottoms of Caldera Bay, northern Chile (27° 03’ S, 70° 51’ W. Due to the ecological and economic impact the species is having in Caldera Bay and its potential spread along the Chilean coastline, we studied the taxonomic identity of the species and examined its relationships with other dichotomous species of Codium reported for temperate Pacific South America. Morphological analyses suggest that the seaweeds from Caldera Bay belong to Codium fragile (Suringar Hariot. Not only is there strong agreement in internal and external morphological characters, but among all the species reported for Peru and Chile, this is the only one exhibiting utricles with rounded, apiculate tip terminating in a mucron. This species has a broad geographic distribution in temperate waters. In Chile it was known only from the coasts of Valdivia to the Straits of Magellan (39° 48’ S, 73° 26’ W to 53° 10’ S, 73° 49’ W. This is the first record of C. fragile in northern Chile, and this study discusses several alternative hypotheses for the presence of the species into this area. The morphological characteristics of the material collected in Caldera partially agree with diagnostic characters known for C. fragile subspecies tasmanicum and C. fragile subspecies tomentosoides. However, the rapid population spread of the species in northern Chile, and recent molecular analysis support the identification of this form as the invasive C. fragile subspecies tomentosoidesA fines de 2001 y principio de 2002, apareció en el norte de Chile una especie del género Codium, de morfología dicotómica, colonizando los niveles intermareales y submareales de la Bahía de Caldera (27° 03’ S, 70° 51’ O. Debido al impacto ecológico y económico que ha provocado esta especie en la Bahía de Caldera y a su dispersión potencial a lo largo de la costa de

Determination of selected elements in red, brown and green seaweed species for monitoring pollution in the coastal environment of Ghana

International Nuclear Information System (INIS)

Serfor-Armah, Y.; Ghana Atomic Energy Commission, Legon-Accra; Ghana University, Legon-Accra; Carboo, D.; Akuamoah, R.K.; Chatt, A.

2006-01-01

The concentrations of 23 elements, namely Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hf, Hg, I, K, La, Mg, Mn, Na, Ni, Sc, Sm, V, and Zn, in seven Rhodophyta (red), three Phaeophyta (brown) and five Chlorophyta (green) seaweed species from different areas along the coast of Ghana were determined using instrumental neutron activation analysis (INAA). These species can be potentially used as biomonitors. The INAA method involved irradiations using thermal and epithermal neutrons at the Dalhousie University SLOWPOKE-2 Reactor (DUSR) facility followed by conventional and anti-coincidence γ-ray spectrometry. The precision in terms of relative standard deviation was within ±4%. The accuracy of the methods was evaluated by analyzing four reference materials. Our results were within ±3% of the certified or information values in all cases. (author)

Seasonal variation in biomass and species composition of seaweeds stranded along Port Okha, northwest coast of India

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Thakur, Mukund C.; Reddy, C. R. K.; Jha, Bhavanath

2008-06-01

Port Okha coast, which is known for its luxuriant growth of a diverse assemblage of seaweeds on Saurashtra coast, is found to have abundant quantities of seaweeds being drifted and washed ashore every year. Studies conducted for quantifying the stranded seaweeds from May 2004 to April 2005 showed an average biomass value of 3.10 kg fresh wt/m2/month with maximum being 6.60 kg fresh wt/m2 in April. The stranded weeds constituted a total of 62 species during the entire study period. Of this, Rhodophyta ranked high with 26 species followed by Chlorophyta with 22 species and Phaeophyta with 14 species. The stranded seaweeds that were washed ashore provide valuable floristic information about the intertidal and near shore sub-tidal algae of the respective regions. Although natural senescence of seaweeds is one of the major factors, strong currents primarily forced by tides, also contribute to the uprooting and subsequent drifting of seaweeds on to the beach. This ultimately causes changes in floristic features of the existing algal beds.

Phytoplankton species composition of four ecological provinces in Yellow Sea, China

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Li, Xiaoqian; Feng, Yuanyuan; Leng, Xiaoyun; Liu, Haijiao; Sun, Jun

2017-12-01

The ecological province based on phytoplankton species composition is important to understanding the interplay between environmental parameters and phytoplankton species composition. The aim of this study was to establish phytoplankton species composition ecological pattern thus elucidate the relationship between environmental factors and the phytoplankton species composition in the ecological provinces. Phytoplankton samples were collected from 31 stations in Yellow Sea (121.00°-125.00°E, 32.00°-39.22°N) in November 2014. The samples were enumerated and identified with the Utermöhl method under an optical inverted microscope-AE2000 with magnifications of 200 × or 400 ×. In the present study, a total of 141 taxa belonging to 60 genera of 4 phyla of phytoplankton were identified, among them 101 species of 45 genera were Bacillariophyta, 36 species of 11 genera were Dinophyta, 3 species of 3 genera were Chrysophyta and 1 species of 1 genera was Chlorophyta. The study area was divided into 4 ecological provinces according to an unsupervised cluster algorithm applied to the phytoplankton biomass. A T-S (Temperature-Salinity) scatter diagram depicted with data of water temperature and salinity defined by environmental provinces matched well with the ecological provinces. The results of Canonical Correspondence Analysis (CCA) indicated that the phytoplankton species composition was mainly correlated with temperature, salinity and silicate concentration in the studied area. A method of establishing ecological provinces is useful to further understanding the environmental effects on the marine phytoplankton species composition and the consequent marine biogeochemistry.

Trace metal concentration in some marine algae of the Maharashtra coast (India)

Digital Repository Service at National Institute of Oceanography (India)

Agadi, V.V.; Bhosle, N.B.; Untawale, A.G.

74 marine algal species representing Chlorophyta, Phaeophyta and Rhodophyta from ten different stations along the Maharashtra Coast were analysed for the concentration of Mn, Fe, Co, Ni, Cu, Zn and Pb Concentration varies with species and also from...

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

The stranded weeds constituted a total of 62 species during the entire study period.Of this,Rhodophyta ranked high with 26 species followed by Chlorophyta with 22 species and Phaeophyta with 14 species.The stranded seaweeds that were washed ashore provide valuable floristic information about the intertidal and near ...

Chlorococcales nuevas para el embalse Paso de las Piedras (Buenos Aires, Argentina New Chlorococcales for Paso de las Piedras Reservoir (Buenos Aires, Argentine

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Carolina Fernández

2005-12-01

Full Text Available En el presente trabajo se citan e ilustran 22 especies pertenecientes al orden Chlorococcales (Chlorophyceae, Chlorophyta halladas en el embalse Paso de las Piedras que representan nuevas citas para este ambiente. Pseudokirchneriella subcapitata, Tetraedron hemisphaericum y Scenedesmus semipulcher constituyen nuevas citas para la República Argentina.In this paper, we record and illustrate 22 species of Chlorococcales (Chlorophyceae, Chlorophyta found in Paso de las Piedras Reservoir, which are new records for this area. Pseudokirchneriella subcapitata, Tetraedron hemisphaericum and Scenedesmus semipulcher are new for Argentina.

Detection of Genetic Variations in Marine Algae Ulva lactuca (Chlorophyta Induced by Heavy Metal Pollutants

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Basel Saleh

2015-09-01

Full Text Available Ulva lactuca (Chlorophyta green macroalgae has been successfully used as bioindicator for heavy metals pollution in ecosystems. Random amplified microsatellite polymorphism (RAMP marker was employed to investigate genetic DNA pattern variability in green U. lactuca 5 days after exposure to Cu, Pb, Cd and Zn heavy metals stress. Genomic template stability (GTS% value was employed as a qualitative DNA changes measurement based on RAMP technique. In this respect, estimated GTS% value was recorded to be 65.215, 64.630, 59.835 and 59.250% for Pb, Cu, Cd and Zn treatment, respectively. Moreover, genetic similarity (GS induced by the above heavy metals was also evaluated to measure genetic distance between algae treated plants and their respective control. In this respect, estimated GS values generated by RAMP marker ranged between 0.576 (between control and Zn treatment - 0.969 (for both case; between Pb and Cu and between Cd and Zn treatment with an average of 0.842. Based upon data presented herein based on variant bands number (VB, GTS% and GS values; the present study could be suggested that Pb and Cu followed similar tendency at genomic DNA changes. Similar finding was also observed with Cd and Zn ions. Thereby, RAMP marker successfully highlighted DNA change patterns induced by heavy metals stress.

Combining and Comparing Coalescent, Distance and Character-Based Approaches for Barcoding Microalgaes: A Test with Chlorella-Like Species (Chlorophyta.

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Shanmei Zou

Full Text Available Several different barcoding methods of distinguishing species have been advanced, but which method is the best is still controversial. Chlorella is becoming particularly promising in the development of second-generation biofuels. However, the taxonomy of Chlorella-like organisms is easily confused. Here we report a comprehensive barcoding analysis of Chlorella-like species from Chlorella, Chloroidium, Dictyosphaerium and Actinastrum based on rbcL, ITS, tufA and 16S sequences to test the efficiency of traditional barcoding, GMYC, ABGD, PTP, P ID and character-based barcoding methods. First of all, the barcoding results gave new insights into the taxonomic assessment of Chlorella-like organisms studied, including the clear species discrimination and resolution of potentially cryptic species complexes in C. sorokiniana, D. ehrenbergianum and C. Vulgaris. The tufA proved to be the most efficient barcoding locus, which thus could be as potential "specific barcode" for Chlorella-like species. The 16S failed in discriminating most closely related species. The resolution of GMYC, PTP, P ID, ABGD and character-based barcoding methods were variable among rbcL, ITS and tufA genes. The best resolution for species differentiation appeared in tufA analysis where GMYC, PTP, ABGD and character-based approaches produced consistent groups while the PTP method over-split the taxa. The character analysis of rbcL, ITS and tufA sequences could clearly distinguish all taxonomic groups respectively, including the potentially cryptic lineages, with many character attributes. Thus, the character-based barcoding provides an attractive complement to coalescent and distance-based barcoding. Our study represents the test that proves the efficiency of multiple DNA barcoding in species discrimination of microalgaes.

Combining and Comparing Coalescent, Distance and Character-Based Approaches for Barcoding Microalgaes: A Test with Chlorella-Like Species (Chlorophyta)

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Zou, Shanmei; Fei, Cong; Song, Jiameng; Bao, Yachao; He, Meilin; Wang, Changhai

2016-01-01

Several different barcoding methods of distinguishing species have been advanced, but which method is the best is still controversial. Chlorella is becoming particularly promising in the development of second-generation biofuels. However, the taxonomy of Chlorella–like organisms is easily confused. Here we report a comprehensive barcoding analysis of Chlorella-like species from Chlorella, Chloroidium, Dictyosphaerium and Actinastrum based on rbcL, ITS, tufA and 16S sequences to test the efficiency of traditional barcoding, GMYC, ABGD, PTP, P ID and character-based barcoding methods. First of all, the barcoding results gave new insights into the taxonomic assessment of Chlorella-like organisms studied, including the clear species discrimination and resolution of potentially cryptic species complexes in C. sorokiniana, D. ehrenbergianum and C. Vulgaris. The tufA proved to be the most efficient barcoding locus, which thus could be as potential “specific barcode” for Chlorella-like species. The 16S failed in discriminating most closely related species. The resolution of GMYC, PTP, P ID, ABGD and character-based barcoding methods were variable among rbcL, ITS and tufA genes. The best resolution for species differentiation appeared in tufA analysis where GMYC, PTP, ABGD and character-based approaches produced consistent groups while the PTP method over-split the taxa. The character analysis of rbcL, ITS and tufA sequences could clearly distinguish all taxonomic groups respectively, including the potentially cryptic lineages, with many character attributes. Thus, the character-based barcoding provides an attractive complement to coalescent and distance-based barcoding. Our study represents the test that proves the efficiency of multiple DNA barcoding in species discrimination of microalgaes. PMID:27092945

Novel green algal isolates from the Egyptian hyper-arid desert oases: a polyphasic approach with a description of Pharao desertorum gen. et sp. nov. (Chlorophyceae, Chlorophyta).

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Saber, Abdullah A; Fučíková, Karolina; McManus, Hilary A; Guella, Graziano; Cantonati, Marco

2018-03-30

The biodiversity of terrestrial algae is still grossly understudied, and African deserts in particular are barely touched in this respect. Here, four coccoid green algae from oases in the Western Desert of Egypt were characterized using a combination of morphotaxonomic, ecological and 18S rDNA data, with additional carotenoid and lipid analyses for two of the strains. Three strains were identified as affiliated with known taxa: Mychonastes sp., Asterarcys sp. (first report of this genus from a desert soil), and Stichococcus cf. deasonii. The fourth strain is proposed to represent a new cryptic genus Pharao gen. nov., with the type species P. desertorum sp. nov. The new taxon is sister to the clade of uncharacterized North American desert strains of Radiococcaceae (Chlorophyceae, Chlorophyta). The pigment profile of P. desertorum gen. et sp. nov. revealed carotenoids and chlorophylls typical of green algae. Bioorganic analysis showed a complex lipidome based on phospho- (PC), galacto- (MGDG and DGDG), betaine- (DGTS), and sulfoquinovosyl- (SQDG) membrane lipids, besides significant amounts of storage neutral lipids such as diacyl- (DAG) and triacylglycerols (TAG). The presence of saturated alkyl chains within all the membrane lipid classes in P. desertorum and Asterarcys sp. appears to reflect the need to maintain membrane fluidity and viscosity. In summary, African deserts likely still harbor new taxa to be described, and lipidomic analyses of such taxa may provide clues about their ability to survive in the extremely harsh desert habitats. © 2018 Phycological Society of America.

Isolation, expression and characterization of rbcL gene from Ulva prolifera J. Agardh (Ulvophyceae, Chlorophyta)

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Shao, Zhanru; Li, Wei; Guo, Hui; Duan, Delin

2015-12-01

Ulva prolifera is a typical green alga in subtidal areas and can grow tremendously fast. A highly efficient Rubisco enzyme which is encoded by UpRbcL gene may contribute to the rapid growth. In this study, the full-length UpRbcL open reading frame (ORF) was identified, which encoded a protein of 474 amino acids. Phylogenetic analysis of UpRbcL sequences revealed that Chlorophyta had a closer genetic relationship with higher plants than with Rhodophyta and Phaeophyta. The two distinct residues (aa11 and aa91) were presumed to be unique for Rubisco catalytic activity. The predicted three-dimensional structure showed that one α/β-barrel existed in the C-terminal region, and the sites for Mg2+ coordination and CO2 fixation were also located in this region. Gene expression profile indicated that UpRbcL was expressed at a higher level under light exposure than in darkness. When the culture temperature reached 35°C, the expression level of UpRbcL was 2.5-fold lower than at 15°C, and the carboxylase activity exhibited 13.8-fold decrease. UpRbcL was heterologously expressed in E. coli and was purified by Ni2+ affinity chromatography. The physiological and biochemical characterization of recombinant Rubisco will be explored in the future.

Epiphytic dinoflagellates associated with ciguatera in the northwestern coast of Cuba

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Gilma Delgado

2006-06-01

Full Text Available The spatial and temporal abundance of epiphytic dinoflagellates associated with ciguatera was studied over two annual cycles (March 1999 to March 2000 and March 2001 to March 2002 in the northwestern coast of Cuba. From 14 species of macroalgae (Phaeophyta, Chlorophyta, and Rhodophyta, 1340 samples were obtained identifying seven species as potentially noxious; five of them are new reports for Cuba’s phytobenthos: Prorocentrum belizeanum Faust, P. concavum Fukuyo, P. mexicanum Tafall, Coolia monotis Meunier, and Ostreopsis lenticularis Fukuyo. ANOVA/MANOVA analysis showed significant spatial differences: lower cell abundance near the shoreline adjacent to a river inlet and higher cell abundance in the deepest area. Prorocentrum lima (Ehrenberg Dodge 1975 was found mainly on Phaeophyta followed by Chlorophyta and Rhodophyta. Gambierdiscus toxicus was found mainly on Phaeophyta followed by Rhodophyta and Chlorophyta. All the species reported in the study area were mainly on Padina spp. (Phaeophyta. Acanthophora spicifera (Rhodophyta did not host dinoflagellate species. Environmental conditions in summer (higher temperature, more nutrients, greater water transparency, and low wind intensity are suitable for macroalgae development, which serves as a substrate for potentially harmful dinoflagellates, and possibly the main vector for spreading ciguatera along the coast of Cuba. Rev. Biol. Trop. 54(2: 299-310. Epub 2006 Jun 01.Se estudió la abundancia espacial y temporal de dinoflagelados epífitos asociados a la ciguatera durante dos ciclos anuales (marzo 1999 a marzo 2000, y marzo 2001 a marzo 2002 en la costa del noroeste de Cuba. Recolectamos 14 especies de macroalgas (Phaeophyta, Chlorophyta y Rhodophyta y obtuvimos 1340 muestras. Identificamos siete especies de dinoflagelados potencialmente nocivas, cinco de ellas nuevos registros para el fitobentos cubano: Prorocentrum belizeanum Faust, P. concavum Fukuyo, P. mexicanum Tafall, Coolia monotis

Studies on structure and organization of calcium carbonate deposits in algae

Digital Repository Service at National Institute of Oceanography (India)

Kerkar, V.; Untawale, A.G.

The structure and organization of calcium carbonate deposits is studied in species of Halimeda, Udotea, Neomeris (Chlorophyta) and Padina (Phaeophyta). It was found that in Halimeda aragonite deposition takes place outside the cell wall...

Ecology of intertidal benthic algae of Northern Karnataka coast

Digital Repository Service at National Institute of Oceanography (India)

Untawale, A.G.; Reddy, C.R.K.; Deshmukhe, G.V.

The intertidal benthic marine algal flora has been studied for distribution, phenology, biomass and zonation along with the environmental conditions. About 65 species belonging to 42 genera of Chlorophyta, Phaeophyta have been recorded. Rhodophyta...

Contributions to the study of the marine algae inhabiting Umluj Seashore, Red Sea

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Ibraheem Borie Mohammad Ibraheem

2014-12-01

Full Text Available The marine algal flora of the Umluj city received no attention about the marine macroalgae. In this paper a total of 19 species are reported for the first time as occurring in the Umluj coast of Saudi Arabia. These species related to Chlorophyta (1, Phaeophyceae (6 and Rhodophyceae (12.

Main nutritional contents of 30 Dalian coastal microalgae species

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Su, Xiurong; Liu, Huihui; Chen, Kwan Paul

2004-12-01

This paper reports results of study on the contents of proteins, amino acids, polysaccharose and uronic acids in 30 species of macroalgae from Shicao, Heishijiao, Shimiao, and Xiaofujiazhuang in the vicinity of Dalian City, N.E.China. The results showed that the protein contents of the 30 algae from highest (112.55 μ g/ml) to the lowest (0.24 μg/ml) was in the descending order of Dictyopteris ndalata, Gelidium vagum, Gymnogongrus japonican, Ectocarpus confervoides, Tinocladia crassa, Sargassum thunberii. In general, the protein content in red algae was higher than that in brown algae. The content of free amino acids showed no significent differences from 7.44 μg/ml4.96 μg/ml in all these algae, in the descending order of Gymnogongrus japonican, Sargassum confusum, Undoria pinnatifida, Laminaria japonica and Ectocarpus confervoides. The content of polysaccharose varied from 168.2 μ/ml-22.15 μg/ml in the descending order of Symphocladia latiuscula, Scytosiphon lomentarius, Desmarestia viridis., Tinocladia crassa, Gracilaria asiatica and Porphyra yezoensis. The content of uronic acids is from 196.24μg/ml-20.77 μg/ml in the descending order of Ulva lactuca, Symphyoclaldia latiuscula, Scytosiphon lomentarius, Ceramimum kodoi, Gracilaria vemucosa and Porphyra yezoensis. The fatty acids in 30 species of algae belong to Rhodophyta, Chlorophyta and Phaeophyta. Most phaeophytes have many (4 12) types of fatty acids.

Carotenoids, Phenolic Compounds and Tocopherols Contribute to the Antioxidative Properties of Some Microalgae Species Grown on Industrial Wastewater

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Safafar, Hamed; van Wagenen, Jonathan; Møller, Per; Jacobsen, Charlotte

2015-01-01

This study aimed at investigating the potential of microalgae species grown on industrial waste water as a new source of natural antioxidants. Six microalgae from different classes, including Phaeodactylum sp. (Bacillariophyceae), Nannochloropsis sp. (Eustigmatophyceae), Chlorella sp., Dunaniella sp., and Desmodesmus sp. (Chlorophyta), were screened for their antioxidant properties using different in vitro assays. Natural antioxidants, including pigments, phenolics, and tocopherols, were measured in methanolic extracts of microalgae biomass. Highest and lowest concentrations of pigments, phenolic compounds, and tocopherols were found in Desmodesmus sp. and Phaeodactylum tricornuotom microalgae species, respectively. The results of each assay were correlated to the content of natural antioxidants in microalgae biomass. Phenolic compounds were found as major contributors to the antioxidant activity in all antioxidant tests while carotenoids were found to contribute to the 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activity, ferrous reduction power (FRAP), and ABTS-radical scavenging capacity activity. Desmodesmus sp. biomass represented a potentially rich source of natural antioxidants, such as carotenoids (lutein), tocopherols, and phenolic compounds when cultivated on industrial waste water as the main nutrient source. PMID:26690454

Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

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Aline P. Martins

2012-08-01

Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

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Aline P. Martins

2012-06-01

Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

Phytoplankton diversity and abundance in Ndop wetland plain ...

African Journals Online (AJOL)

Eight divisions of phytoplankton were recorded: Chlorophyta (26.42%), Bacillariophyta (20.76%), Pyrrhophyta (20.76%), Cyanophyta (15.09%), Chrysophyta (1.87%), Xanthophyta (3.77%), Rhodophyta (1.87%), and Euglenophyta (7.55%). The most abundant species included Microcystis aeruginosa, Anacystis sp., ...

Fitoplancton de un río del noroeste argentino contaminado por efluentes azucareros y cloacales Phytoplankton from an ArgentineanNorwestRiver contaminated by sewage and sugarcane effluents

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V. Mirande

2005-12-01

Full Text Available El río Gastona es uno de los tributarios más contaminados del embalse Río Hondo (Tucumán-Santiago del Estero. Presenta en épocas de zafra azucarera (junio-octubre condiciones de anoxia con alteraciones de los componentes nitrogenados y fosforado, entre otros factores. El objetivo de este trabajo fue caracterizar la calidad del agua de acuerdo a los grupos de especies fitoplanctónicas y sus densidades encontrados en 1998-1999. Se seleccionaron cinco sitios según la zona de descarga de los efluentes domésticos y fabriles, realizándose muestreos mensuales por el término de trece meses, a partir de marzo. Los índices bióticos empleados fueron: Compuesto, Déficit de Especies, Índice de Diatomeas Pampeano, Euglenal, Centrales/Pennales, Chlorophyta/Chrysophyta (diatomeas y Relaciones Abundancia-Especies. Los resultados obtenidos destacaron una mayor sensibilidad de las Chlorophyta a los efectos de la materia orgánica. Los cuatro primeros índices anteriormente nombrados fueron los más efectivos para diferenciar los períodos de no zafra y zafra.Gastona River is one of the tributaries more contaminated from Río Hondo Dam (Tucumán-Santiago del Estero. This river presents in sugarcane activity period (June-October anoxic conditions and alterations of nitrogen and phosphoric components, between others causes. The aim of this paper was to characterize the water quality in agreement to species groups and densities of phytoplankton found in 1998-1999. We were selected five sampling sites along the river in relation to sewage and industry effluents discharge areas. Sampling were realized monthly and during thirteen months. We began the sampling on March. Indices employed were: Composite; Species Deficit; Pampeano Diatom Index; Euglenal; Centrales/Pennales; Chlorophyta/Chrysophyta (diatoms and Density-Species Relations. The results obtained showed that Chlorophyta were the group most sensitive to organic mater effects. The four first indices

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. Detelina Belkinova. Articles written in Journal of Genetics. Volume 85 Issue 1 April 2006 pp 39-44 Research Article. Karyotypic differences and evolutionary tendencies of some species from the subgenus Obliquodesmus Mlad. of genus Scenedesmus Meyen (Chlorophyta, ...

Checklist of the benthic marine and brackish Galician algae (NW Spain

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Bárbara, Ignacio

2005-06-01

Full Text Available We present an annotated checklist of the benthic marine and brackish algae of the Galician coasts (Spain based on literature records and new collections. This checklist includes 618 species: 118 Cyanophyta, 296 Rhodophyta, 127 Ochrophyta, and 77 Chlorophyta. The number of specific, infraspecific taxa, and stages is 643: 121 Cyanophyta, 309 Rhodophyta, 135 Ochrophyta, and 79 Chlorophyta. Hyella caespitosa var. nitida, Calothrix fasciculata, Gracilariopsis longissima, Compsonema minutum, and Sphacelaria tribuloides are new records for Galicia, and there are also some new provincial records. We state the presence of each species for Lugo (Lu, A Coruña (Co, and Pontevedra (Po provinces. The number of species found in Galicia is high, since 85% of the species recorded for the warm-temperate NE Atlantic Ocean grow in Galicia. Biogeographical comments comparing the Galician data with the neighboring areas of Britain and Ireland, Basque coast, Portugal, southern Iberian Peninsula, Canary Islands and Atlantic coast of Morocco are given. Finally, we present lists of cold-temperate, warm-temperate, Lusitanic Province endemics, and alien species growing in Galicia.Se presenta una lista comentada de las especies de algas bentónicas marinas y salobres de la costa de Galicia (España basada en citas bibliográficas y nuevos datos de los autores. La lista contiene 618 especies: 118 Cyanophyta, 296 Rhodophyta, 127 Ochrophyta y 77 Chlorophyta. El número de taxa específicos e infraespecíficos asciende a 643: 121 Cyanophyta, 309 Rhodophyta, 135 Ochrophyta y 79 Chlorophyta. Hyella caespitosa var. nitida, Calothrix fasciculata, Gracilariopsis longissima, Compsonema minutum y Sphacelaria tribuloides son nuevas citas para Galicia, y algunas nuevas citas provinciales. Para cada especie se especifica su presencia en las provincias de Lugo (Lu, A Coruña (Co y Pontevedra (Po. El número de especies encontradas en Galicia es elevado, ya que se conocen el 85% de las

Spatial and temporal patterns of phytoplankton abundance and ...

African Journals Online (AJOL)

Bacillariophyta was the most abundant group (48.17% of total phytoplankton) and was uniformly distributed in all waters, followed by Cyanobacteria (33.33%), which decreased with distance offshore. Chlorophyta, the third highest in abundance (15.5%), increased with distance offshore. A total of 92 phytoplankton species ...

α-, β-caroteno e α-tocoferol em algas marinhas in natura α- and β-carotene, and α-tocopherol in fresh seaweeds

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Márcia Barbosa de Sousa

2008-12-01

Full Text Available O objetivo deste trabalho foi avaliar o potencial de 32 espécies de algas marinhas das divisões Chlorophyta, Rhodophyta e Phaeophyta como fontes de α- e β-caroteno e α-tocoferol. Todas as clorofíceas analisadas apresentaram α- e β-caroteno. Os teores máximo e mínimo de α-caroteno foram detectados nas espécies do gênero Caulerpa e em Codium decorticatum, respectivamente; e β-caroteno foi mais baixo em Caulerpa mexicana e mais elevado em Ulva fasciata. Dentre as rodofíceas, 11 espécies apresentaram α-caroteno, com máximo em Botryocladia occidentalis. β-caroteno foi encontrado em todas as algas vermelhas analisadas com teores mínimo e máximo em Gracilaria caudata e Bryothamnion triquetrum, respectivamente. As feofíceas apresentaram apenas β-caroteno, com mínimo e máximo em Dictyopteris delicatula e Padina gymnospora, respectivamente. Na divisão Chlorophyta, α-tocoferol, foi máximo em Codium decorticatum e mínimo em Caulerpa prolifera. Na Rhodophyta, 12 espécies apresentaram α-tocoferol com teor máximo em Enantiocladia duperreyi. Na Phaeophyta, α-tocoferol foi encontrado com valores mínimo e máximo em Lobophora variegata e Dictyota dichotoma, respectivamente.The aim of this work was to evaluate the potential of 32 marine macro algae species, members of Chlorophyta, Rhodophyta and Phaeophyta, as sources of a-carotene, b-carotene and a-tocopherol. Both b-carotene and a-carotene were found in all species of green macroalgae analyzed. The maximum content of a-carotene was detected in algae belonging to Caulerpa genus and the minimum in Codium decorticatum. The amount of b-carotene found was minimum in Caulerpa mexicana and maximum in Ulva fasciata. Among the Rhodophyta species, eleven contain a-carotene, the maximum content was found in Botryocladia occidentalis. b-Carotene was found in all red macroalgae analyzed presenting the lowest and highest values in Gracilaria caudata and Bryothamnion triquetrum, respectively

Ecological-floristic analysis of soil algae and cyanobacteria on the Tra-Tau and Yurak-Tau Mounts, Bashkiria

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Bakieva, G. R.; Khaibullina, L. S.; Gaisina, L. A.; Kabirov, R. R.

2012-09-01

The species composition of the soil algae and cyanobacteria in the Tra-Tau and Yurak-Tau mountains is represented by 136 species belonging to five phyla: Cyanobacteria (56 species), Chlorophyta (52 species), Xanthophyta (13 species), Bacillariophyta (12 species), and Eustigmatophyta (3 species). Hantzschia amphioxys var. amphioxys, Hantzschia amphioxys var. constricta, Klebsormidium flaccidum, Leptolyngbya foveolarum, Luticola mutica, Navicula minima var. minima, Nostoc punctiforme, Phormidium jadinianum, Phormidium autumnale, and Pinnularia borealis were identified more often than other species. The composition of the algal flora depended on the soil properties; the higher plants also had a significant influence on the species composition of the soil algae.

Seasonal variations in biomass and species composition of seaweeds along the northern coasts of Persian Gulf (Bushehr Province)

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Dadolahi-Sohrab, A.; Garavand-Karimi, M.; Riahi, H.; Pashazanoosi, H.

2012-02-01

This study was carried out to evaluate the seasonal variations of seaweed biomass and species composition at six different sites along the coastal areas in Bushehr Province. Sampling depths varied among sites, from 0.3 to 2.0 m below mean sea level. A total of 37 (i.e., 10 Chlorophyta, 12 Phaeophyta and 15 Rhodophyta) seaweed species were collected. Studies were conducted for quantifying the seaweeds during four seasons from October 2008 until July 2009. During present research, Ulva intestinalis and Cladophora nitellopsis of green, Polycladia myrica, Sirophysalia trinodis and Sargassum angustifolium of brown and Gracilaria canaliculata and Hypnea cervicornis of red seaweeds showed highest biomass in coastal areas of Bushehr Province. The Cheney`s ratio of 2.1 indicated a temperate algal flora to this area. All sites exhibited more than 50% similarity of algal species, indicating a relatively homogenous algal distribution. Total biomass showed the highest value of 3280.7 ± 537.8 g dry wt m - 2 during summer and lowest value of 856.9 ± 92.0 g dry wt m - 2 during winter. During this study, the highest and lowest seaweed biomass were recorded on the site 2 (2473.7 ± 311.0 g dry wt m - 2) and site 5 (856.7 ± 96.8 g dry wt m - 2), respectively.

Biodiesel synthesis via transesterification of lipid Chlorophyta cultivated in walne rich carbon medium using KOH/Zeolite catalyst

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Dianursanti, Hayati, Siti Zahrotul; Putri, Dwini Normayulisa

2017-11-01

Microalgae from the Chlorophyta division such as Nannochloropsis oculata and Chlorella vulgaris are highly potential to be developed as biodiesel feedstocks because they have a high oil content up to 58%. Biodiesel is produced by transesterification of triglycerides and alcohols with the aid of homogeneous catalysts such as KOH. However, the use of KOH catalysts produces soaps in the biodiesel synthesis. Heterogeneous catalysts are known to solve this problem. One of them is natural zeolite. Zeolite can be used as a catalyst and as a support catalyst. Loading KOH on the zeolite surface is expected to increase alkalinity in KOH/Zeolite catalysts so as to increase the activity of KOH/Zeolite catalyst in transesterification of triglyceride with methanol. In this experimental lipid of microalgae will be used for produced biodiesel via transesterification reaction with methanol and KOH/Zeolite as a catalyst heterogeneous at 60 °C for 3h and utilized catalyst modificated KOH/Zeolite with variation 0.5 M, 1 M and 1.5 M KOH. The modified zeolite was then analyzed by XRF, XRD and BET. The result showed that the yield of biodiesel from lipid N.oculata was 81,09% by 0.5KOH/Zeolite catalyst, 86,53% by 1KOH/Zeolite catalyst, 1,5KOH/Zeolite and 88,13% by 1.5KOH/Zeolit, while the biodiesel produced from lipid C.vulgaris was 59.29% by 0.5KOH/Zeolite, 82.27% by 1KOH/Zeolite and 83.72% by 1.5KOH/Zeolite.

Antiviral activity of extracts from Brazilian seaweeds against herpes simplex virus

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Angélica Ribeiro Soares

2012-08-01

Full Text Available Organic extracts of 36 species of marine algae (sixteen species of Rhodophyta, eight species of Ochrophyta and twelve species of Chlorophyta from seven locations on the Brazilian coast were evaluated for their anti-HSV-1 and anti-HSV-2 activity resistant to Acyclovir (ACV. Activity tests in crude extracts, followed by the identification of the major compounds present, were performed for all species. The chemical profiles of all crude extracts were obtained by ¹H-NMR and 13C-NMR spectroscopy. The percentage of extracts with antiviral activity was higher for HSV-1 (86.1% than for HSV-2 (55.5%. The green algae Ulva fasciata and Codium decorticatum both showed the highest activity (99.9% against HSV-1, with triacylglycerols and fatty acids as the major components. The red alga Laurencia dendroidea showed good activity against HSV-1 (97.5% and the halogenated sesquiterpenes obtusol and (--elatol were identified as the major components in the extract. Against HSV-2, the green alga Penicillus capitatus (Chlorophyta and Stypopodium zonale (Ochrophyta were the most active (96.0 and 95.8%. Atomaric acid, a meroditerpene, was identified as the major secondary metabolite in the S. zonale extract. These results reinforce the role of seaweeds as important sources of compounds with the potential to enter into the pipeline for development of new drugs against herpes simplex.

Antiviral activity of extracts from Brazilian seaweeds against herpes simplex virus

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Angélica Ribeiro Soares

2012-05-01

Full Text Available Organic extracts of 36 species of marine algae (sixteen species of Rhodophyta, eight species of Ochrophyta and twelve species of Chlorophyta from seven locations on the Brazilian coast were evaluated for their anti-HSV-1 and anti-HSV-2 activity resistant to Acyclovir (ACV. Activity tests in crude extracts, followed by the identification of the major compounds present, were performed for all species. The chemical profiles of all crude extracts were obtained by ¹H-NMR and 13C-NMR spectroscopy. The percentage of extracts with antiviral activity was higher for HSV-1 (86.1% than for HSV-2 (55.5%. The green algae Ulva fasciata and Codium decorticatum both showed the highest activity (99.9% against HSV-1, with triacylglycerols and fatty acids as the major components. The red alga Laurencia dendroidea showed good activity against HSV-1 (97.5% and the halogenated sesquiterpenes obtusol and (--elatol were identified as the major components in the extract. Against HSV-2, the green alga Penicillus capitatus (Chlorophyta and Stypopodium zonale (Ochrophyta were the most active (96.0 and 95.8%. Atomaric acid, a meroditerpene, was identified as the major secondary metabolite in the S. zonale extract. These results reinforce the role of seaweeds as important sources of compounds with the potential to enter into the pipeline for development of new drugs against herpes simplex.

[Epiphytic algae from Bajo Pepito, Isla Mujeres, Quintana Roo, Mexico].

Science.gov (United States)

Quan-Young, L I; Díaz-Martín, M A; Espinoza-Avalos, J

2006-06-01

A total of 96 epiphytic algae species were identified from Bajo Pepito, Quintana Roo, México. 60.4% (58) belonged to the Rhodophyta, 19.79% (19) to the Phaeophyta, 16.6% (16) to the Chlorophyta and 3.1% (3) to the Cyanophyta; 49 species (50.5%) were found only in one month, while Heterosiphonia crispella was found in all of the sampled months. That species provided the largest contribution to the biomass of epiphytes. During January we registered the greater biommass and richness of epiphytes species, coincidently with high values of host species cover and rainfall.

Impacts of Environmental Variables on a Phytoplankton Community: A Case Study of the Tributaries of a Subtropical River, Southern China

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Zhaojiang Hou

2018-02-01

Full Text Available The phytoplankton community in the river is closely related to the location of the river and the impact of human activities. To summarize the patterns of phytoplankton community changes in rivers and to analyze the reasons for these patterns and differences, we sampled the three tributaries of the Dongjiang River at different latitudes in the dry and rainy season for three years. The results showed that the three rivers were mesotrophic, lightly eutrophic and moderately eutrophic respectively. From the south to the north, the water temperature and nutrition showed an increasing trend. In two different seasons, the differences in the water temperature and dissolved oxygen were clear. In the dry season, results of the multidimensional scaling (MDS analysis indicated that the phytoplankton community structures in the Li River and Qiuxiang River were similar. Regardless of the number of species, the cell abundance or the dominance index, Bacillariophyta were found to be dominant. Chlorophyta was dominant in the Danshui River. In the rainy season, Bacillariophyta, Bacillariophyta-Chlorophyta and Chlorophyta-Cyanophyta became the dominant types in the Li River, Qiuxiang River and Danshui River, respectively. These different patterns in phytoplankton community variation were affected by both the water quality and temperature.

New records of Scenedesmus Meyen from China

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ZHU Yaru

2012-08-01

Full Text Available One species,four variant and one forma of Chlorophyta Scenedesmus are first reported in China,they are Scenedesmus ecornis var.disciformis,S.acutus f.alternans,S.ginzbergeri,S.intermedius var. bicaudatus,S.opoliensis var. polycostatus and S.opoliensis var.bicaudatus.The taxonomic characters were described for each taxon by micro-photography and pictures.

Effects of copper on species composition of periphyton in a Sierra Nevada, California, stream

Energy Technology Data Exchange (ETDEWEB)

Leland, H.V.; Carter, J.L.

1984-06-01

Changes in species composition of the periphyton of an oliotrophic, Sierra Nevada stream continuously dosed for 1 year at three concentrations of copper (2.5, 5 and 10..mu..g 1/sup -1/ Cu/sub T/; approximately 12, 25 and 50 ng 1/sup -1/ Cu/sup 2 +/) were determined. The numerically most abundant taxa were Bacillariophyceae (Achnanthes minutissima, Cocconeis placentula, Cymbella microcephala, C. sinuata, Fragilaria construens, F. crotonensis, Navicula spp., Synedra acus and S. rumpens), and the Cyanophyta Lynbya spp., a co-dominant during spring and summer. Population densities of Lyngbya spp. were markedly reduced at all test concentrations of copper. Population densities of the principal Chlorophyta (Spirogyra spp. and Cladophora spp.) and the diatom Amphipleura pellucida were reduced at 5 ..mu..g 1/sup -1/ Cu/sub T/. Of the twenty-two most abundant taxa, sixteen were reduced in abundance by continuous exposure to 10 ..mu..g 1/sup -1/ Cu/sub T/. There was no commensurate reduction in standing crop (total number of individuals of all taxa). Achnanthes minutissima, a co-dominant in the control, was the primary replacement species. Other taxa that were more abundant at 5 ..mu..g 1/sup -1/ Cu/sub T/ than in the control were Ceratoneis arcus, Cocconeis placentula, Navicula spp. and Synedra rumpens. Only A. minutissima and Calothrix spp. were more abundant at l10 ..mu..g 1/sup -1/ than in the control. Three resemblance measures (Canberra metric, Bray-Curtis and Dice) and diversity (Brillouin's) were evaluated for detecting differences in species composition among experimental stream sections. The Canberra metric, an index sensitive to proportional rather than absolute differences, was the most informative of these indices.

Antifungal activity of aqueous and methanolic extracts of some seaweeds against common soil-borne plant pathogenic fungi

International Nuclear Information System (INIS)

Khan, S.A.; Abid, M.; Hussain, F.

2017-01-01

Total 32 species of different seaweeds belonging to Chlorophyta, Phaeophyta and Rhodophyta were collected from the coast of Karachi, Pakistan to investigate their antifungal activity. Most of the seaweeds inhibited growth of Fusarium oxypsorum, Macrophomina phaseolina and Rhizoctonia solani. The highest antifungal activities were observed in Sargasssum tenerrimum in both aqueous and methanolic extracts as compared to other seaweeds. (author)

Ecological distribution of stream macroalgal communities from a drainage basin in the Serra da Canastra National Park, Minas Gerais, Southeastern Brazil

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Necchi-Júnior O.

2003-01-01

Full Text Available Twelve stream segments were sampled four times in 1998-1999 (one sampling per season in the drainage basin of the upper São Francisco River (19º45'-21º25'S, 49º05'-51º30'W, situated in Serra da Canastra National Park, at altitudes ranging from 1,175 to 1,400 m. The macroalgae survey resulted in 30 species, with a predominance of Cyanophyta (12 species = 40% and Chlorophyta (11 species = 36.5% and a lower proportion of Rhodophyta (seven species = 23.5%. Two species, Klebsormidium rivulare (Chlorophyta and Kyliniella latvica (Rhodophyta, were new records for Brazil. Capsosira sp. and Stigonema sp. (Cyanophyta and the "Chantransia" stage of Batrachospermum (Rhodophyta were the most widespread macroalgae, occurring in six sampling sites, whereas 11 species were found at only one site. The proportion of macroalgal morphological types were as follows: mats (33%, free filaments (27%, gelatinous filaments (27%, crusts (7%, tufts (3%, and gelatinous colonies (3%. The flora revealed few species in common (4%-8% with stream macroalgae from other Brazilian regions. The macroalgal communities proved to have species richness values close to the highest values reported in previous studies. The patterns typical for stream macroalgal communities (patchy distribution and dominance of few species were also found in this basin. However, the stream variables most influential in macroalgal distribution in this study (rocky substratum, low pH, high COD, water color, and current velocity were essentially the same that best describe the limnological characteristics of this lotic ecosystem. In addition, this combination of variables differed sharply from results of previous studies in other Brazilian stream ecosystems.

Gain and loss of polyadenylation signals during evolution of green algae

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Glöckner Gernot

2007-04-01

Full Text Available Abstract Background The Viridiplantae (green algae and land plants consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related sequence 13 to 30 nucleotides upstream from the cleavage site, which is commonly referred to as the near upstream element (NUE. However, it has been reported that the pentanucleotide UGUAA is used as polyadenylation signal for some genes in volvocalean algae. Results We set out to investigate polyadenylation signal differences between streptophytes and chlorophytes that may have emerged shortly after the evolutionary split between Streptophyta and Chlorophyta. We therefore analyzed expressed genes (ESTs from three streptophyte algae, Mesostigma viride, Klebsormidium subtile and Coleochaete scutata, and from two early-branching chlorophytes, Pyramimonas parkeae and Scherffelia dubia. In addition, to extend the database, our analyses included ESTs from six other chlorophytes (Acetabularia acetabulum, Chlamydomonas reinhardtii, Helicosporidium sp. ex Simulium jonesii, Prototheca wickerhamii, Scenedesmus obliquus and Ulva linza and one streptophyte (Closterium peracerosum. Our results indicate that polyadenylation signals in green algae vary widely. The UGUAA motif is confined to late-branching Chlorophyta. Most streptophyte algae do not have an A-rich sequence motif like that in embryophytes, animals and fungi. We observed polyadenylation signals similar to those of Arabidopsis and other land plants only in Mesostigma. Conclusion Polyadenylation signals in green algae show considerable variation. A new NUE (UGUAA was invented in derived chlorophytes and replaced

Gain and loss of polyadenylation signals during evolution of green algae.

Science.gov (United States)

Wodniok, Sabina; Simon, Andreas; Glöckner, Gernot; Becker, Burkhard

2007-04-18

The Viridiplantae (green algae and land plants) consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related sequence) 13 to 30 nucleotides upstream from the cleavage site, which is commonly referred to as the near upstream element (NUE). However, it has been reported that the pentanucleotide UGUAA is used as polyadenylation signal for some genes in volvocalean algae. We set out to investigate polyadenylation signal differences between streptophytes and chlorophytes that may have emerged shortly after the evolutionary split between Streptophyta and Chlorophyta. We therefore analyzed expressed genes (ESTs) from three streptophyte algae, Mesostigma viride, Klebsormidium subtile and Coleochaete scutata, and from two early-branching chlorophytes, Pyramimonas parkeae and Scherffelia dubia. In addition, to extend the database, our analyses included ESTs from six other chlorophytes (Acetabularia acetabulum, Chlamydomonas reinhardtii, Helicosporidium sp. ex Simulium jonesii, Prototheca wickerhamii, Scenedesmus obliquus and Ulva linza) and one streptophyte (Closterium peracerosum). Our results indicate that polyadenylation signals in green algae vary widely. The UGUAA motif is confined to late-branching Chlorophyta. Most streptophyte algae do not have an A-rich sequence motif like that in embryophytes, animals and fungi. We observed polyadenylation signals similar to those of Arabidopsis and other land plants only in Mesostigma. Polyadenylation signals in green algae show considerable variation. A new NUE (UGUAA) was invented in derived chlorophytes and replaced not only the A-rich NUE but the complete poly

Accumulation of 210Po by benthic marine algae

International Nuclear Information System (INIS)

Gouvea, R.C.; Branco, M.E.C.; Santos, P.L.

1988-01-01

The accumulation of polonium 210 Po by various species of benthic marine seaweeds collected from 4 different points on the coast of Rio de Janeiro, showed variations by species and algal groups. The highest value found was in red alga, Plocamium brasiliensis followed by other organisms of the same group. In the group of the brown alga, the specie Sargassum stenophylum was outstanding. The Chlorophyta presented the lowest content of 210 Po. The algae collected in open sea, revealed greater concentration factors of 210 Po than the same species living in bays. The siliceous residue remaining after mineralization of the algae did not interfere with the detection of polonium. (author)

Seasonal variations in the biochemical composition of some common seaweed species from the coast of Abu Qir Bay, Alexandria, Egypt

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Hanan M. Khairy

2013-05-01

Full Text Available Variations in protein, carbohydrate, lipid, ash, moisture, fatty acid and aminoacid contents of the seaweeds Ulva lactuca Linnaeus (Chlorophyta,Jania rubens (Linnaeus J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin Bornet(Rhodophyta were studied seasonally from spring to autumn 2010. The seaweeds were collected from a rocky site near Boughaz El-Maadya on the coast of Abu Qir Bay east of Alexandria, Egypt. Remarkable seasonal variations were recorded in the levels of the studied parameters in the three species. Pterocladia capillacea was characterized by the highest protein andcarbohydrate content throughout the different seasons, whereas Ulva lactuca contained more lipids (4.09 ± 0.2% than J. rubens and P. capillacea. The highest total fatty acids were recorded in J. rubens during the three seasons, while saturated fatty acids were predominant in P. capillacea during spring. This is due mainly to the presence of palmitic acid(C16:0, which made up 74.3% of the saturated fatty acids. The highest level of polyunsaturated fatty acids (PUFA in these algae was measured in J. rubens; DHA (22:6ω3 was the main acid, making up 26.4% of the total fatty acids especiallyduring summer. Proline was the major component of the amino acids in the three algal species, with maximum amounts in U. lactuca.

Freshwater algae of the Nevada Test Site

International Nuclear Information System (INIS)

Taylor, W.D.; Giles, K.R.

1979-06-01

Fifty-two species of freshwater algae were identified in samples collected from the eight known natural springs of the Nevada Test Site. Although several species were widespread, 29 species were site specific. Diatoms provided the greatest variety of species at each spring. Three-fifths of all algal species encountered were diatoms. Well-developed mats of filamentous green algae (Chlorophyta) were common in many of the water tanks associated with the springs and accounted for most of the algal biomass. Major nutrients were adequate, if not abundant, in most spring waters - growth being limited primarily by light and physical habitat. There was some evidence of cesium-137 bioconcentration by algae at several of the springs

Twenty new Records of Algae in some Springs around Safeen Mountain Area

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Farhad Hassan Aziz

2016-07-01

Full Text Available This study was carried out in 2015-2016 within Erbil governorate. A total of 151 algal species were identified from 8 divisions, 9 classes, 24 orders, 37 families and 72 genera. The majority species were belonged to Chlorophyta with 68 species (45.033%, followed by Cyanophyta with 46 species (30.463%, Euglenophyta with 18 species (11.92%, Chrysophyta with 12 species (7.947%, Charophyta with 3 species occupied (1.987%,  Rhodophyta with 2 species (1.32% and each of Cryptophyta and Pyrrophyta with one species occupied (0.662%. Among them, 20 species and 6 genera are new records to Iraqi flora viz.: Komvophoron constrictum, Nephrocytium agardhianum, Lepocinclis fusiformis, Petalomonas sp., Heteronema acus, Peranema trichophorum and Chilomonas paramecium were recorded as new to the Iraqi algal flora.

Seasonal variations in the biochemical composition of some common seaweed species from the coast of Abu Qir Bay, Alexandria, Egypt

OpenAIRE

Khairy, Hanan M.; El-Shafay, Shimaa M.

2013-01-01

Variations in protein, carbohydrate, lipid, ash, moisture, fatty acid and aminoacid contents of the seaweeds Ulva lactuca Linnaeus (Chlorophyta),Jania rubens (Linnaeus) J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin) Bornet(Rhodophyta) were studied seasonally from spring to autumn 2010. The seaweeds were collected from a rocky site near Boughaz El-Maadya on the coast of Abu Qir Bay east of Alexandria, Egypt. Remarkable seasonal variations were recorded in the levels of the studied pa...

Algas epífitas de Bajo Pepito, Isla Mujeres, Quintana Roo, México

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L.I Quan-Young

2006-06-01

Full Text Available Epiphytic algae from Bajo Pepito, Isla Mujeres, Quintana Roo, México. A total of 96 epiphytic algae species were identified from Bajo Pepito, Quintana Roo, México. 60.4% (58 belonged to the Rhodophyta, 19.79% (19 to the Phaeophyta, 16.6% (16 to the Chlorophyta and 3.1% (3 to the Cyanophyta; 49 species (50.5% were found only in one month, while Heterosiphonia crispella was found in all of the sampled months. That species provided the largest contribution to the biomass of epiphytes. During January we registered the greater biommass and richness of epiphytes species, coincidently with high values of host species cover and rainfall. Rev. Biol. Trop. 54(2: 317-328. Epub 2006 Jun 01.

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.

Biodiversity of cyanobacteria and green algae on monuments in the Mediterranean Basin: an overview.

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Macedo, Maria Filomena; Miller, Ana Zélia; Dionísio, Amélia; Saiz-Jimenez, Cesareo

2009-11-01

The presence and deteriorating action of micro-organisms on monuments and stone works of art have received considerable attention in the last few years. Knowledge of the microbial populations living on stone materials is the starting point for successful conservation treatment and control. This paper reviews the literature on cyanobacteria and chlorophyta that cause deterioration of stone cultural heritage (outdoor monuments and stone works of art) in European countries of the Mediterranean Basin. Some 45 case studies from 32 scientific papers published between 1976 and 2009 were analysed. Six lithotypes were considered: marble, limestone, travertine, dolomite, sandstone and granite. A wide range of stone monuments in the Mediterranean Basin support considerable colonization of cyanobacteria and chlorophyta, showing notable biodiversity. About 172 taxa have been described by different authors, including 37 genera of cyanobacteria and 48 genera of chlorophyta. The most widespread and commonly reported taxa on the stone cultural heritage in the Mediterranean Basin are, among cyanobacteria, Gloeocapsa, Phormidium and Chroococcus and, among chlorophyta, Chlorella, Stichococcus and Chlorococcum. The results suggest that cyanobacteria and chlorophyta colonize a wide variety of substrata and that this is related primarily to the physical characteristics of the stone surface, microclimate and environmental conditions and secondarily to the lithotype.

[Ecological characteristics of phytoplankton in Suining tributary under bio-remediation].

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Liu, Dongyan; Zhao, Jianfu; Zhang, Yalei; Ma, Limin

2005-04-01

Based on the analyses of phytoplankton community in the treated and untreated reaches of Suining tributary of Suzhou River, this paper studied the effects of bio-remediation on phytoplankton. As the result of the remediation, the density and Chl-a content of phytoplankton in treated reach were greatly declined, while the species number and Shannon-Wiener diversity index ascended obviously. The percentage of Chlorophyta and Baeillariophyta ascended, and some species indicating medium-and oligo-pollution were found. All of these illustrated that bio-remediation engineering might significantly benefit to the improvement of phytoplankton community structure and water quality.

Spatial patterns of seaweed distribution in Malaysia using GIS

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Lian, Du Hai; Sim, Jillian Ooi Lean; Fauzi, Rosmadi; Moi, Phang Siew

2008-10-01

The objective of this article is to represent spatial patterns of seaweed distribution in Malaysia. Seaweeds have been collected since 1984 along coastlines of 4675 km of peninsular Malaysia, Sabah, and Sarawak. However, there is no seaweed database and they cannot be displayed in a geographic view. Therefore, a database with 805 georeferenced observations was setup and GIS is used to analyze seaweed diversity based on this database. The highest number of observations is 94 which occur along east coastline of peninsular Malaysia. The highest number of species richness is 82 which are also along east coastline of peninsular Malaysia. Rhodophyta has the highest species richness while Chlorophyta has the least species richness.

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...

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...

Analysis of expressed sequence tags from the Ulva prolifera (Chlorophyta)

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Niu, Jianfeng; Hu, Haiyan; Hu, Songnian; Wang, Guangce; Peng, Guang; Sun, Song

2010-01-01

In 2008, a green tide broke out before the sailing competition of the 29th Olympic Games in Qingdao. The causative species was determined to be Enteromorpha prolifera ( Ulva prolifera O. F. Müller), a familiar green macroalga along the coastline of China. Rapid accumulation of a large biomass of floating U. prolifera prompted research on different aspects of this species. In this study, we constructed a nonnormalized cDNA library from the thalli of U. prolifera and acquired 10 072 high-quality expressed sequence tags (ESTs). These ESTs were assembled into 3 519 nonredundant gene groups, including 1 446 clusters and 2 073 singletons. After annotation with the nr database, a large number of genes were found to be related with chloroplast and ribosomal protein, GO functional classification showed 1 418 ESTs participated in photosynthesis and 1 359 ESTs were responsible for the generation of precursor metabolites and energy. In addition, rather comprehensive carbon fixation pathways were found in U. prolifera using KEGG. Some stress-related and signal transduction-related genes were also found in this study. All the evidences displayed that U. prolifera had substance and energy foundation for the intense photosynthesis and the rapid proliferation. Phylogenetic analysis of cytochrome c oxidase subunit I revealed that this green-tide causative species is most closely affiliated to Pseudendoclonium akinetum (Ulvophyceae).

Seaweed composition from Bintulu coast of Sarawak, Malaysia.

Science.gov (United States)

Zawawi, Mohd Hafizbillah; Idris, Mohd Hanafi; Kamal, Abu Hena Mustafa; King, Wong Sing

2014-08-01

Species composition of seaweed and distribution were investigated in the coastal waters of Bintulu, Sarawak. The seaweed samples were collected during low tide between May 2011 and May 2012 from the six different stations. In total 54 species of seaweeds were identified from study areas of Bintulu coastal waters. Among them, 23 species were from Rhodophyta with 11 families, 15 species were from Phaeophyta with 2 families and 16 species were from Chlorophyta with 10 families: Seventeen species of seaweeds were recorded from the Tanjung Batu, while 23 species from Pantai Telekom, 14 species from Golden Beach, 26 species from Kuala Similajau, 12 species from Kuala Nyalau and 21 species from Batu Mandi. Seaweeds abundance was high in rocky substrate and Rhodophyta (11 families and 23 species) was the common and highest group of seaweeds in this coastal areas. Present study recorded high diversified seaweed species at the rocky shore area compare to reef area.

Phytoplankton composition of Sazlidere Dam lake, Istanbul, Turkey

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Nese Yilmaz

2013-05-01

Full Text Available The phytoplankton composition of Sazlidere Dam lake was studied at 5 sampling sites between December 2003 - November 2005. A total of 67 taxa were recorded, representing Bacillariophyta (31, Chlorophyta (18, Cyanophyta (9, Chrysophyta (1, Cryptophyta (1, Dinophyta (3 and Euglenophyta (4. Bacillariophyta members constituted the dominant phytoplankton group in terms of species number. Nygaard’s compound index value and composition of phytoplankton indicate that the trophic state of Sazlidere Dam lake was changing from oligotrophic to mesotrophic.

Taxonomic assessment of seaweed community from the coastal areas of Bintulu, Sarawak, Malaysia

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Mohd Hafizbillah Zawawi

2015-04-01

Full Text Available Basic taxonomic information forms the important basis for the documentation, resource management and utilization of marine biodiversity such as seaweeds. A taxonomic assessment of seaweeds in the coastal areas of Bintulu, Sarawak, East Malaysia, was conducted monthly from May 2011 to May 2012. Species composition was recorded following NaGISA protocols, direct observation, and SCUBA and snorkeling techniques. A total of 54 species were identified, classified into Rhodophyta (23 species, Chlorophyta (16 species and Phaeophyta (15 species. The highest abundance was recorded at Kuala Similajau (25 species while the lowest was recorded at Kuala Nyalau (12 species. As the present study was conducted by examining species collected from both rocky shores and the reef area for the first time, a higher number of species was documented compared to previous studies conducted in the same general area but focusing only on particular habitats. Thirty species found in the current survey represent new records for the locality including some with economic potentials.

Screening for antibacterial and antifungal activities in some marine algae from the Fujian coast of China with three different solvents

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Zheng, Yi; Chen, Yin-Shan; Lu, Hai-Sheng

2001-12-01

Three different solvents viz ethanol, acetone and methanol-toluene (3:1) were used to extract antibiotics from 23 species of marine algae belonging to the Chlorophyta, Phaeophyta and Rhodophyta. Their crude extracts were tested for antibacterial and antifungal activities. Among them, the ethanol extract showed the strongest activity against the bacteria and fungi tested. Four species of the Rhodophyta ( Laurencia okamurai, Dasya scoparia, Grateloupia filicina and plocamium telfairiae) showed a wide spectrum of antibacterial activity. Every solvent extract from the four species was active against all the bacteria tested. The test bacterium Pseudomonas solancearum and the fungus Penicilium citrinum were most sensitive to the extracts of marine algae. In general, the extracts of seaweeds inhibited bacteria more strongly than fungi and species of the Rhodophyta showed the greatest activity against the bacteria and fungi tested.

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.

Cyanobacterial and microcystins dynamics following the application of hydrogen peroxide to waste stabilisation ponds

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Barrington, D. J.; Ghadouani, A.; Ivey, G. N.

2013-06-01

Cyanobacteria and cyanotoxins are a risk to human and ecological health, and a hindrance to biological wastewater treatment. This study investigated the use of hydrogen peroxide (H2O2) for the removal of cyanobacteria and cyanotoxins from within waste stabilization ponds (WSPs). The daily dynamics of cyanobacteria and microcystins (commonly occurring cyanotoxins) were examined following the addition of H2O2 to wastewater within both the laboratory and at the full scale within a maturation WSP, the final pond in a wastewater treatment plant. Hydrogen peroxide treatment at concentrations ≥ 0.1 mg H2O2 μg-1 total phytoplankton chlorophyll a led to the lysis of cyanobacteria, in turn releasing intracellular microcystins to the dissolved state. In the full-scale trial, dissolved microcystins were then degraded to negligible concentrations by H2O2 and environmental processes within five days. A shift in the phytoplankton assemblage towards beneficial Chlorophyta species was also observed within days of H2O2 addition. However, within weeks, the Chlorophyta population was significantly reduced by the re-establishment of toxic cyanobacterial species. This re-establishment was likely due to the inflow of cyanobacteria from ponds earlier in the treatment train, suggesting that whilst H2O2 may be a suitable short-term management technique, it must be coupled with control over inflows if it is to improve WSP performance in the longer term.

Cyanobacterial and microcystins dynamics following the application of hydrogen peroxide to waste stabilisation ponds

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D. J. Barrington

2013-06-01

Full Text Available Cyanobacteria and cyanotoxins are a risk to human and ecological health, and a hindrance to biological wastewater treatment. This study investigated the use of hydrogen peroxide (H2O2 for the removal of cyanobacteria and cyanotoxins from within waste stabilization ponds (WSPs. The daily dynamics of cyanobacteria and microcystins (commonly occurring cyanotoxins were examined following the addition of H2O2 to wastewater within both the laboratory and at the full scale within a maturation WSP, the final pond in a wastewater treatment plant. Hydrogen peroxide treatment at concentrations ≥ 0.1 mg H2O2 μg−1 total phytoplankton chlorophyll a led to the lysis of cyanobacteria, in turn releasing intracellular microcystins to the dissolved state. In the full-scale trial, dissolved microcystins were then degraded to negligible concentrations by H2O2 and environmental processes within five days. A shift in the phytoplankton assemblage towards beneficial Chlorophyta species was also observed within days of H2O2 addition. However, within weeks, the Chlorophyta population was significantly reduced by the re-establishment of toxic cyanobacterial species. This re-establishment was likely due to the inflow of cyanobacteria from ponds earlier in the treatment train, suggesting that whilst H2O2 may be a suitable short-term management technique, it must be coupled with control over inflows if it is to improve WSP performance in the longer term.

Macroalgae and macrozoobenthos of the Pčinja river

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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.

Phenotypic and genetic characterization of Dunaliella (Chlorophyta) from Indian salinas and their diversity

Science.gov (United States)

2012-01-01

Background The genus Dunaliella (Class – Chlorophyceae) is widely studied for its tolerance to extreme habitat conditions, physiological aspects and many biotechnological applications, such as a source of carotenoids and many other bioactive compounds. Biochemical and molecular characterization is very much essential to fully explore the properties and possibilities of the new isolates of Dunaliella. In India, hyper saline lakes and salt pans were reported to bloom with Dunaliella spp. However, except for the economically important D. salina, other species are rarely characterized taxonomically from India. Present study was conducted to describe Dunaliella strains from Indian salinas using a combined morphological, physiological and molecular approach with an aim to have a better understanding on the taxonomy and diversity of this genus from India. Results Comparative phenotypic and genetic studies revealed high level of diversity within the Indian Dunaliella isolates. Species level identification using morphological characteristics clearly delineated two strains of D. salina with considerable β-carotene content (>20 pg/cell). The variation in 18S rRNA gene size, amplified with MA1-MA2 primers, ranged between ~1800 and ~2650 base pairs, and together with the phylogeny based on ITS gene sequence provided a pattern, forming five different groups within Indian Dunaliella isolates. Superficial congruency was observed between ITS and rbcL gene phylogenetic trees with consistent formation of major clades separating Indian isolates into two distinct clusters, one with D. salina and allied strains, and another one with D. viridis and allied strains. Further in both the trees, few isolates showed high level of genetic divergence than reported previously for Dunaliella spp. This indicates the scope of more numbers of clearly defined/unidentified species/sub-species within Indian Dunaliella isolates. Conclusion Present work illustrates Indian Dunaliella strains

PHYTOPLANKTON OF CASPIAN

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Aysha Sharapatinovna Gasanova

2015-01-01

Full Text Available Aim. The composition of the species of the phytoplankton in the Russian sector of the Caspian Sea in conditions of transgression, anthropogenic and chemical contamination has been studied.Location.The Russian sector of the Caspian SeaMethods. The phytoplankton samples were collected at the depths of 8 – 50m by the use of the Nansen bathometer and subsequently were fixed in 4% formalin. The office processing was carried out in a box of Nozhotta type, which has the volume of 0.1 ml and the triplicate surface, under the light microscope of Biolam P15. The system of domestic diamotologists was used during the classification of Bacillariaphyta, as for the classification of Dinophyta, the Dodge scheme was applied. Cyanophyta algae were classified according to the system of A.A. Elenkina with the amendments adopted by A.I. Proshkin-Lavrenko and V.V. Makarova. The classification of the Chlorophyta division has been done according to the Smith system.Results, main conclusions. Presented the taxonomic structure and the lists of species of the phytoplankton community in the sea coastal shallow waters Russian sector of the Caspian Sea have been presented. A high floristic diversity and domination of small cell forms are characteristics of the modern structure of the coastal shoal waters of the Dagestan part of the Caspian Sea. The auttaclimatizant of 1934, Pseudosolenia calcaravis, has not been discovered in the plankton of the researched water area. The phytoplankton community has been represented by 58 species of six groups: Cyanophyta, Bacillariaphyta, Dinophyta, Euglenophyta, Chlorophyta and the small flagellate. Bacillariaphyta were the basis of both the taxonomic diversity and the biomass. Cyanophita prevailed in number.

Aquatic macro algae of a region under Almirante Alvaro Alberto nuclear power plant influence. I. Taxonomic composition

International Nuclear Information System (INIS)

Pedrini, A.G.; Universidade Santa Ursula, Rio de Janeiro, RJ; Cassano, V.; Coelho, L.G.; Labronici, G.J.

1994-01-01

A total of 134 taxa were found: 32 Chlorophyta, 29 Phaeophyta and 74 Rhodophyta. The Caulerpales (Chlorophyta) had the highest number of taxa (37,5%) followed by the Dictyotales (Phaeophyta - 43%) and Ceramiales (Rhodophyta - 53%). The benthic flora shows some affinity to that of Ilha Grande (part), Sepetiba Bay and Paraty (Sorensen's Index - 0,62, 0,61 and 0,58 respectively. (author). 22 refs, 1 fig, 1 tab

Aquatic macro algae of a region under Almirante Alvaro Alberto nuclear power plant influence. I. Taxonomic composition; Macroalgas marinhas da regiao sob influencia da Central Nuclear Almirante Alvaro Alberto, Angra dos Reis, RJ, Brasil. I. Composicao taxonomica

Energy Technology Data Exchange (ETDEWEB)

Pedrini, A.G. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil)]|[Universidade Santa Ursula, Rio de Janeiro, RJ (Brazil). Centro de Ciencias Biologicas; Cassano, V.; Coelho, L.G.; Labronici, G.J. [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia

1994-12-31

A total of 134 taxa were found: 32 Chlorophyta, 29 Phaeophyta and 74 Rhodophyta. The Caulerpales (Chlorophyta) had the highest number of taxa (37,5%) followed by the Dictyotales (Phaeophyta - 43%) and Ceramiales (Rhodophyta - 53%). The benthic flora shows some affinity to that of Ilha Grande (part), Sepetiba Bay and Paraty (Sorensen`s Index - 0,62, 0,61 and 0,58 respectively. (author). 22 refs, 1 fig, 1 tab.

Pseudoderbesia, nuevo género de algas marinas (Bryopsidaceae, Chlorophyta Pseudoderbesia, nuevo género de algas marinas (Bryopsidaceae, Chlorophyta

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Calderon Eduardo

1991-06-01

Full Text Available Se aislaron cuatro clones de Pseudoderbesia y se mantuvieron como cultivos unialgales: dos provenientes de la Costa Colombiana del Caribe (P. arbuscula y dos de las Islas Canarias en el Océano Atlántico (Pseudoderbesia sp.. Aunque se conoce solo la fase gametofítica, hay razones suficientes para el establecimiento de un nuevo género. Se describe y discute el crecimiento, variabilidad, producción bajo condiciones de cultivo. Se sugiere la posibilidad que ciertas especies de Derbesia que poseen ramificación dicotómica y filamentos gradualmente atenuados, como D. fastigiata, D. attenuata y D. padinae, sean realmente miembros de Pseudoderbesia. Pseudoderbesia is described as a new genus within the Bryopsidaceae. Four clones of Pseudoderbesia were isolated and kept as unialgal cultures: two from the Caribbean coast of Colombia (P. arbuscula and two from the Canary Islands, Atlantic Ocean (Pseudoderbesia sp.. Although only the gametophytic phase is known, it is distinct enough for the establishement of a new genus. Growth, variability and swarmer production, under culture conditions, are described and discussed. It is suggested, that some little known species of Derbesia with dichotomous branching and gradually attenuated filaments, like D. fastigiata, D. attenuata and D. padinae, could actually be members of Pseudoderbesia.

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.

Check-list of the Basque coast benthic algae (North of Spain

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Gorostiaga, José M.

2004-12-01

Full Text Available An annotated check-list of the marine benthic flora of the Spanish Basque coast, based on literature records and original data, is presented. According to the present taxonomy, the known list of algae totals 372 taxa (354 species and 18 infraspecific taxa, distributed as follows: 23 Cyanophyta, 221 Rhodophyta, 74 Heterokontophyta and 54 Chlorophyta. In addition, 16 taxa are considered as taxa inquirenda and 8 as taxa excludenda. For each taxon the vertical distribution, abundance estimation, and two first published records are given. Remarks on the most noteworthy features of the flora of the study area are included. The floristic character of Spanish Basque coast flora was compared with nearby regions applying Cheney’s ratio [(Rhodophyta+ Chlorophyta/Phaeophyta, or (R+C/P]. The resulting high value (4,09 indicates its warm-water character, which was already noted at the end of the XIX century. From a physionomical point of view, Basque benthic vegetation resembles more closely that of southern regions (S Portugal, Morocco. The warming process of waters off the Basque coast during summer up to 22 ºC is responsible for the absence or very rare occurrence of cold temperate species like large fucoids and kelps, which are common in Galicia and Brittany, and explains the abundance of numerous warm-temperate species as ceramiaceous algae.Se presenta un catálogo de la flora bentónica marina de la costa vasco-española basado en citas bibliográficas y algunos datos originales. De acuerdo con la taxonomía actual, la lista de algas conocidas asciende a 372 táxones (354 especies y 18 táxones infraespecíficos, que se distribuyen como sigue: 23 Cyanophyta, 221 Rhodophyta, 74 Heterokontophyta y 54 Chlorophyta. Además, 16 táxones se consideran como taxa inquirenda y 8 como taxa excludenda. Para cada taxon se ofrece información sobre su distribución vertical, una estima de su abundancia y las dos primeras citas publicadas. Se incluyen

Diversity of Phytoplankton of a sub-tropical reservoir of Mizoram, northeast India

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Bhushan Kumar Sharma

2016-12-01

Full Text Available Phytoplankton of Khawiva reservoir of Mizoram, northeast India (NEI revealed a total of 55 species; nearly concurrent mean monthly richness and high community similarities (vide Sørensen index during two years affirmed homogeneity in its species composition. Phytoplankton comprised dominant component (61.1±14.3% of net plankton and recorded wider density variations. Chlorophyta influenced phytoplankton abundance with quantitative importance of Staurastrum spp. >Xanthidium spp. >Cosmarium spp. in particular. Bacillariophyta formed subdominant group; Cryptophyta and Cyanophyta showed limited importance; and Euglenophyta and Dinophyta recorded poor densities. Phytoplankton is characterized by moderate species diversity, high evenness and low dominance but with wide variations. Richness, abundance and species diversity followed no definite patterns of monthly variations during two years. Insignificant influence of individual abiotic factors on phytoplankton assemblages coupled with low cumulative influence of fifteen abiotic parameters (vide CCA yielded little insight on overall role of abiotic parameters.

SOIL ALGAE OF BLADE OF COIL IN DONETSK REGION

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Maltseva I.A.

2011-12-01

Full Text Available On territory of Donbass for more than 200 years the underground coal mining has produced, accompanied by the formation of the mine dumps. Finding ways to reduce their negative impact on the environment should be based on their comprehensive study. The soil algae are active participants in the syngenetic processes in industrial dumps of different origin. The purpose of this paper is to identify the species composition and dominant algae groups in dump mine SH/U5 “Western” in the western part of Donetsk.The test blade is covered with vegetation to the middle from all sides, and on the north side of 20-25 m to the top. The vegetation cover of the lower and middle tiers of all the exposures range in 70-80%. Projective vegetation cover of upper tiers of the northern, north-eastern and north-western exposures are in the range of 20-40%, other – 5-10%. We revealed some 38 algae species as a result of our research in southern, northern, western, and eastern slopes of the blade “Western”. The highest species diversity has Chlorophyta - 14 species (36.8% of the total number of species, then Cyanophyta - 9 (23,7%, Bacillariophyta - 7 (18,4%, Xantophyta - 5 (13.2%, and Eustigmatophyta - 3 (7.9%. The dominants are represented by Hantzschia amphyoxys (Ehrenberg Grunow in Cleve et Grunow, Bracteacoccus aerius, Klebsormidium flaccidum (Kützing Silva et al., Phormidium autumnale, Pinnularia borealis Ehrenberg, Planothidium lanceolatum (Brebisson in Kützing Bukhtiyarova, Xanthonema exile (Klebs Silva.It should be noted that the species composition of algae groups in different slopes of the blade was significantly different. Jacquard coefficient was calculated for algae communities varied in the range of 15,4-39,1%. The smallest number of algae species was observed on the southern slope of the blade (14 species, maximum was registered in the areas of north and west slopes. Differences in the species composition of algae were also observed in three

Algal Bio-Indication in Assessment of Hydrological Impact on Ecosystem in Wetlands of “Slavyansky Resort”

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Klymiuk Valentina

2015-06-01

Full Text Available Algal bio-indication is commonly used in water quality assessment but can also help in assessing the impact of hydrology on freshwater wetland ecosystems.We identified 350 species and infraspecific taxa of algae from nine taxonomic divisions (Cyanoprokaryota, Chrysophyta, Euglenophyta,Dinophyta,Xanthophyta,Cryptophyta,Bacillariophyta,Chlorophyta,Charophyta in 121 phytoplankton samples collected between 2007-2013 from seven lakes in the wetlands of the Regional Landscape Park “Slavyansky Resort”, Ukraine. The algal species richness and phytoplankton biomass decreased as water salinity increased. In turn the water salinity was influenced by the inflow of groundwater, karst fracture and by the alluvial water tributaries of a paleoriver that affects the formation processes of lake-spring sulphide mud from the resort, which is often used for therapeutic purposes.

ANTIBACTERIAL ACTIVITY OF BENTHIC MARINE ALGAE EXTRACTS FROM THE MEDITERRANEAN COAST OF MOROCCO

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Hanaâ Zbakh

2012-08-01

Full Text Available Marine organisms are potentially prolific sources of highly bioactive secondary metabolites that might represent useful leads in the development of new pharmaceutical agents. The Moroccan marine biodiversity including macroalgae remains partially unexplored in term of their potential bioactivities. Antibacterial activity of methanolic extracts from 20 species of macroalgae (9 Chlorophyta, 3 Phaeophyta and 8 Rhodophyta collected from Moroccan Mediterranean coasts was evaluated against Escherichia coli, Staphylococcus aureus and Enterococcus faecalis. The extracts of the studied Rhodophyceae inhibited considerably the growth of the three tested bacterial strains and gave inhibition zones between 20 and 24 mm. The results indicate that these species of seaweed present a significant capacity of antibacterial activities, which makes them interesting for screening for natural products.

Accumulation and loss of technetium by macrophytic algae

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Benco, C.; Cannarsa, S.; Ceppodomo, I.; Zattera, A.

1986-01-01

Preliminary results are presented of a study of the accumulation of Tc by four species of brown algae (Sargassum vulgare, Cystoseira complexa, Dictyopteris membranacea, Dictyota dichotama implexa) and one species of green algae (Chlorophyta, Ulva rigida). With the exception of Cystoseira complexa, the accumulation was very rapid, and concentration factors decreased from Sargassum vulgare to Ulva rigida. Young stipes of Cystoseira complexa concentrated twice as much more Tc than cylindrical main axes. Attempts were made to understand the mechanism of Tc accumulation by brown seaweed. Fucoidan, a pool of high molecular weight polysaccharides extracted from Fucus sp. was put with sup(95m)Tc in seawater for 48 h and then dialysed, but no activity was retained by Fucoidan. (UK)

Gain and loss of polyadenylation signals during evolution of green algae

OpenAIRE

Wodniok, Sabina; Simon, Andreas; Glöckner, Gernot; Becker, Burkhard

2007-01-01

Abstract Background The Viridiplantae (green algae and land plants) consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related seq...

The Cladophora complex (Chlorophyta): new views based on 18S rRNA gene sequences.

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Bakker, F T; Olsen, J L; Stam, W T; van den Hoek, C

1994-12-01

Evolutionary relationships among species traditionally ascribed to the Siphonocladales/Cladophorales have remained unclear due to a lack of phylogenetically informative characters and extensive morphological plasticity resulting in morphological convergence. This study explores some of the diversity within the generic complex Cladophora and its siphonocladalaen allies. Twelve species of Cladophora representing 6 of the 11 morphological sections recognized by van den Hoek were analyzed along with 8 siphonocladalaen species using 18S rRNA gene sequences. The final alignment consisted of 1460 positions containing 92 phylogenetically informative substitutions. Weighting schemes (EOR weighting, combinatorial weighting) were applied in maximum parsimony analysis to correct for substitution bias. Stem characters were weighted 0.66 relative to single-stranded characters to correct for secondary structural constraints. Both weighting approaches resulted in greater phylogenetic resolution. Results confirm that there is no basis for the independent recognition of the Cladophorales and Siphonocladales. The Siphonocladales is polyphyletic, and Cladophora is paraphyletic. All analyses support two principal lineages, of which one contains predominantly tropical members including almost all siphonocladalean taxa, while the other lineage consists of mostly warm- to cold-temperate species of Cladophora.

Temperature responses of tropical to warm temperate Cladophora species in relation to their distribution in the North Atlantic Ocean

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Cambridge, M. L.; Breeman, A. M.; Kraak, S.; van den Hoek, C.

1987-09-01

The relationship between distribution boundaries and temperature responses of some North Atlantic Cladophora species (Chlorophyta) was experimentally examined under various regimes of temperature, light and daylength. Experimentally determined critical temperature intervals, in which survival, growth or reproduction was limited, were compared with annual temperature regimes (monthly means and extremes) at sites inside and outside distribution boundaries. The species tested belonged to two phytogeographic groups: (1) the tropical West Atlantic group ( C. submarina: isolate from Curaçao) and (2) the amphiatlantic tropical to warm temperate group ( C. prolifera: isolate from Corsica; C. coelothrix: isolates from Brittany and Curaçao; and C. laetevirens: isolates from deep and shallow water in Corsica and from Brittany). In accordance with distribution from tropical to warm temperate regions, each of the species grew well between 20 30°C and reproduction and growth were limited at and below 15°C. The upper survival limit in long days was <35°C in all species but high or maximum growth rates occurred at 30°C. C. prolifera, restricted to the tropical margins, had the most limited survival at 35°C. Experimental evidence suggests that C. submarina is restricted to the Caribbean and excluded from the more northerly American mainland and Gulf of Mexico coasts by sporadic low winter temperatures in the nearshore waters, when cold northerly weather penetrates far south every few years. Experimental evidence suggests that C. prolifera, C. coelothrix and C. laetevirens are restricted to their northern European boundaries by summer temperatures too low for sufficient growth and/or reproduction. Their progressively more northerly located boundaries were accounted for by differences in growth rates over the critical 10 15°C interval. C. prolifera and C. coelothrix are excluded or restricted in distribution on North Sea coasts by lethal winter temperatures, again differences

Algas marinas bentónicas de la costa noroccidental de Guerrero, México Benthic marine algae of the west coast of Guerrero, Mexico

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Luz Elena Mateo-Cid

2012-12-01

Full Text Available Se presentan los resultados de un estudio sobre algas marinas bentónicas en 7 localidades de la costa noroccidental de Guerrero, México. Se determinó la presencia de 163 especies de algas marinas. Se identificaron 17 especies de Cyanobacteria, 93 Rhodophyta, 28 Chlorophyta y 25 de Heterokontophyta. Se citan 54 registros nuevos para el litoral de Guerrero, 2 también nuevos, Myrionema strangulans Greville y Acrochaete ramosa (N.L.Gardner O'Kelly para la costa del Pacífico. Cada especie se acompaña de datos sobre su distribución en el área de estudio, su estado reproductivo, nivel de marea, hábitat, observaciones, epifitismo y número de herbario o de recolección. Se comparó la riqueza específica entre la estación climática de lluvias y la de secas. La división Rhodophyta dominó en términos de diversidad en relación con las 3 divisiones restantes. La ficoflora de la costa noroccidental de Guerrero es de afinidad tropical y más diversa en la época de secas.We present results on the study on benthic marine algae in 7 localities from the west coast of Guerrero, Mexico. We report 163 species: 17 Cyanobacteria, 93 Rhodophyta, 28 Chlorophyta and 25 Heterokontophyta. Fifty four are new records for Guerrero; while Myrionema strangulans Greville and Acrochaete ramosa (N.L.Gardner O'Kelly are new to the Pacific coast of Mexico. Each species includes data on its distribution, reproductive stages, tidal level, facies, epiphytism and herbarium's number. Species diversity was compared for 2 different climatic seasons. The Rhodophyta are dominant in terms of diversity in relation to the other groups. The algal flora of the northwest coast of Guerrero is tropical and the greatest diversity was found during dry seasons.

EVOLUTIONARY RELATIONSHIPS BETWEEN 4 SPECIES OF CLADOPHORA (CLADOPHORALES, CHLOROPHYTA) BASED ON DNA-DNA HYBRIDIZATION

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BOT, PVM; BRUSSAARD, CPD; STAM, WT; VANDENHOEK, C

1991-01-01

Analysis of the reassociation kinetics of the DNA from Cladophora pellucida (Huds.) Kutz. indicates that the genome of this benthic alga is comprised of approximately 75% repetitive sequences. Single-copy sequences reassociated with a rate constant of 1.8 x 10(-3) M-1.s-1, which corresponds to a

Floristic account of the marine benthic algae from Jarvis Island and Kingman Reef, Line Islands, Central Pacific

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Vroom, P.S.

2012-05-01

Full Text Available The marine benthic algae from Jarvis Island and Kingman Reef were identified from collections obtained from the Whippoorwill Expedition in 1924, the Itasca Expedition in 1935, the U.S. Coast Guard Cutter Taney in 1938, the Smithsonian Institution’s Pacific Ocean Biological Survey Program in 1964 and the U.S. National Oceanic and Atmospheric Administration’s Reef Assessment and Monitoring Program (RAMP in 2000, 2001, 2002, 2004 and 2006. A total of 124 species, representing 8 Cyanobacteria (blue-green algae, 82 Rhodophyta (red algae, 6 Heterokontophyta (brown algae and 28 Chlorophyta (green algae, are reported from both islands. Seventy-nine and 95 species of marine benthic algae are recorded from Jarvis Island and Kingman Reef, respectively. Of the 124 species, 77 species or 62% (4 blue-green algae, 57 red algae, 2 brown algae and 14 green algae have never before been reported from the 11 remote reefs, atolls and low islands comprising the Line Islands in the Central Pacific.

Preliminary observations on the benthic marine algae of the Gorringe seabank (northeast Atlantic Ocean)

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Tittley, Ian; da Silva Vaz Álvaro, Nuno Miguel; de Melo Azevedo Neto, Ana Isabel

2014-06-01

Examination of marine samples collected in 2006 from the Gettysburg and Ormonde seamounts on the Gorringe seabank southwest of Portugal has revealed 29 benthic Chlorophyta, Phaeophyceae (Ochrophyta), and Rhodophyta that were identified provisionally to genus and to species. Combining lists for the present and a previous expedition brings the total of algae thus far recorded to 48. The brown alga Zonaria tournefourtii and the red alga Cryptopleura ramosa were the most abundant species in the present collections. The kelp Laminaria ochroleuca was present only in the Gettysburg samples while Saccorhiza polyschides was observed only on the Ormonde seamount. Comparisons with the benthic marine algae recorded on seamounts in the mid-Atlantic Azores archipelago show features in common, notably kelp forests of L. ochroleuca at depths below 30 m and Z. tournefortii dominance in shallower waters.

EVOLUTION OF NUCLEAR RDNA ITS SEQUENCES IN THE CLADOPHORA ALBIDA/SERICEA CLADE (CHLOROPHYTA)

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BAKKER, FT; OLSEN, JL; STAM, WT

Ribosomal DNA ITS sequences were compared among 13 different species and biogeographic isolates from the monophyletic ''abbida/sericea clade'' in the green algal genus Cladophora. Six distinct ITS sequence types were found, characterized by multiple insertions and deletions and high levels of

Review of alien marine macrophytes in Tunisia

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Y. R. SGHAIER

2015-01-01

Full Text Available In the present study, the list of alien marine macrophytes introduced into Tunisia was updated in the light of available data and new observations. A total of 27 alien marine macrophytes have been recorded so far from Tunisia: 18 Rhodophyta, 3 Ochrophyta, 5 Chlorophyta and 1 Magnoliophyta. For each species, the locality (-ies, the year (or period and the source of the first observation in Tunisia are given. The distribution and the status (casual, cryptogenic, established or questionable of species in Tunisia were evaluated and, where appropriate, discussed. Among them, Hypnea cornuta is reported for the first time from Tunisia. Fourteen alien marine macrophytes are established, whereas seven cryptogenic and two casual species require further investigation. Eleven species are considered as invasive or potentially invasive in the Mediterranean Sea: Acrothamnion preissii, Asparagopsis armata, A. taxiformis Indo-Pacific lineage, Hypnea cornuta, Lophocladia lallemandii, Womersleyella setacea, Caulerpa chemnitzia, C. cylindracea, C. taxifolia, Codium fragile subsp. fragile and Halophila stipulacea. Finally, the case of four questionable species is also discussed.

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

Cyanobacterial-algal cenoses in ordinary chernozems under the impact of different phytoameliorants

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Dubovik, I. E.; Suyundukov, Ya. T.; Khasanova, R. F.; Shalygina, R. R.

2016-04-01

General ecological and taxonomic characteristics of cyanobacterial-algal cenoses in ordinary chernozems under different ameliorative plants (phytoameliorants) were studied in the Trans-Ural region of the Republic of Bashkortostan. A comparative analysis of the taxa of studied cenoses in the soils under leguminous herbs and grasses was performed. The phytoameliorative effect of different herbs and their relationships with cyanobacterial-algal cenoses were examined. Overall, 134 cyanoprokaryotic and algal species belonging to 70 genera, 36 families, 15 orders, and 9 classes were identified. Cyanobacterial-algal cenoses included the divisions of Chlorophyta, Cyanoprokaryota, Xanthophyta, Bacillariophyta, and Euglenophyta. Representatives of Ch-, X-, CF-, and P-forms were the leading ecobiomorphs in the studied cenoses.

Plankton and Macrobiota Composition and Diversity of Three Tropical Freshwaters Rivers in Ogun and Ondo States, Southwest Nigeria

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Taofikat Abosede ADESALU

2016-06-01

Full Text Available Three different rivers in Ogun and Ondo states were investigated for both micro and macro-biota of the water bodies. Several physical and chemical properties of these rivers were determined. The pH value of the studied water bodies was essentially neutral with salinity values between 0.02 - 4.0‰. Microalgae communities were represented by three divisions: Cyanophyta, Bacillariophyta and Chlorophyta at Oluwa and Ifara Rivers (Ondo state, while at Ibefun River (Ogun state, five divisions: Cyanophyta, Bacillariophyta, Chlorophyta, Euglenophyta and Pyrrhophyta were identified. Diatoms dominated these water bodies, with Navicula radiosa Kutz. at Ifara River, Fragilaria sp. in Oluwa River, while out of 90 algal taxa identified in Ibefun river, 64 were diatoms species belonging to 26 genera, with Melosira sp. and Synedra sp. recording the highest numbers of cell count. Dinoflagellates recorded only Peridinium sp. while Phacus orbicularis Hubner and Trachelomonas sp. dominated the euglenoids. For the zooplankton composition at Ibefun, rotifers (75.95% were represented by Brachionus sp., which recorded 62.03%, and Gastropus sp. with 13.92% of the total zooplankton, thus dominated the spectrum, while the copepod recorded 22.78% of the total organisms, with Copilia sp. and Euchirella sp. having 8.86% each. The macrobenthic invertebrates were represented by 3 taxa, belonging to 3 groups, with the dominant group Insecta accounted for 57% of the total individuals (7 individuals/m2, while Oligochaeta and Hirudinea accounted for 29% and 14% respectively of the total individuals at Oluwa and Ifara Rivers. At Ibefun River, the macrobenthic invertebrates were represented by 5 taxa, belonging to 3 groups, Bivalves, Oligochaeta and Insecta, with bivalves being the dominant group (51.7% of the total individuals, as 64 individuals/m2, while Oligochaeta and Insecta accounted for 26.6% and 21.9% respectively of the total individuals. The dominant taxon, Macoma cumana

Epilithic algae from caves of the Krakowsko-Częstochowska Upland (Southern Poland

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Joanna Czerwik-Marcinkowska

2011-01-01

Full Text Available This paper describes the first study of algae assemblages in 20 caves in the Krakowsko-Częstochowska Upland (Southern Poland, in the period between 2005-2006. The investigations showed mostly on epilithic algae and their subaeric habitats (rock faces within caves and walls at cave entrances. The morphological and cytological variability of algae were studied in fresh samples, in cultures grown on agar plates and in SPURR preparations. A total of 43 algae species was identified, mostly epilithic species and tolerant of low light intensities. The largest group was formed by representatives of the division Chlorophyta (24 species, and then the division Chrysophyta (Heterokontophyta - 17 species, with 9 species belonging to the class Bacillariophyceae, 7 species - Xanthophyceae and 1 species representing the class Eustigmatophyceae. Dinophyta (2 species constituted the last and the smallest group. Among the collected algae, the following species deserve special attention: Thelesphaera alpina, Bracteacoccus minor, Trachychloron simplex, Tetracystis intermedia and T. cf. isobilateralis. The last species was not earlier found in Europe. Identification of species was greatly aided by examination of cell ultrastructure, which provided an array of further features, increasing chances of correct species identification. Furthermore, the studies focused that algae, although usually remaining under dominance of cyanobacteria, excellently differentiate this special area and even enrich it.

Bibliographic checklist of the marine benthic algae of Central Polynesia in the Pacific Ocean (Excluding Hawai‘i and French Polynesia

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Tsuda, R.T.

2013-04-01

Full Text Available The Polynesian algal bibliographic checklist is based on records from past references for American Samoa and Samoa (380 spp., Cook Islands (111 spp., Johnston Atoll (190 spp., Line Islands (250 spp., Niue (3 spp., Phoenix Islands (193 spp., Pitcairn Islands (23 spp., Tokelau (1 sp., Tonga (109 spp., Wake Atoll (121 spp. and Wallis and Futuna (191 spp. and consists of three sections. The first section (I. Classification provides a listing of classes, orders, and families of the 238 genera of Polynesian algae. The second section (II. Species-Reference Index provides an alphabetized listing of the 667 named algal species under the four Phyla, i.e., Cyanobacteria (68 species, Rhodophyta (373 species, Ochrophyta (59 species and Chlorophyta (167 species with the applicable reference citations for each island or atoll. Brief taxonomic or nomenclatural notes are provided, when appropriate, for selected species. The third section (III. Island-Reference Index provides a chronological listing of all published references for the respective island or atoll in each island group. The complete references for all citations in the text are provided in the Reference section.

Classification, Naming and Evolutionary History of Glycosyltransferases from Sequenced Green and Red Algal Genomes

Science.gov (United States)

Ulvskov, Peter; Paiva, Dionisio Soares; Domozych, David; Harholt, Jesper

2013-01-01

The Archaeplastida consists of three lineages, Rhodophyta, Virideplantae and Glaucophyta. The extracellular matrix of most members of the Rhodophyta and Viridiplantae consists of carbohydrate-based or a highly glycosylated protein-based cell wall while the Glaucophyte covering is poorly resolved. In order to elucidate possible evolutionary links between the three advanced lineages in Archaeplastida, a genomic analysis was initiated. Fully sequenced genomes from the Rhodophyta and Virideplantae and the well-defined CAZy database on glycosyltransferases were included in the analysis. The number of glycosyltransferases found in the Rhodophyta and Chlorophyta are generally much lower then in land plants (Embryophyta). Three specific features exhibited by land plants increase the number of glycosyltransferases in their genomes: (1) cell wall biosynthesis, the more complex land plant cell walls require a larger number of glycosyltransferases for biosynthesis, (2) a richer set of protein glycosylation, and (3) glycosylation of secondary metabolites, demonstrated by a large proportion of family GT1 being involved in secondary metabolite biosynthesis. In a comparative analysis of polysaccharide biosynthesis amongst the taxa of this study, clear distinctions or similarities were observed in (1) N-linked protein glycosylation, i.e., Chlorophyta has different mannosylation and glucosylation patterns, (2) GPI anchor biosynthesis, which is apparently missing in the Rhodophyta and truncated in the Chlorophyta, (3) cell wall biosynthesis, where the land plants have unique cell wall related polymers not found in green and red algae, and (4) O-linked glycosylation where comprehensive orthology was observed in glycosylation between the Chlorophyta and land plants but not between the target proteins. PMID:24146880

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.

Limnological study of fresh water of rawal dam, islamabad

International Nuclear Information System (INIS)

Leghari, M.K.; Ghafar, S.A.

2005-01-01

The limnological study of Fresh water of Rawal Dam was carried out for the first time from June 2000 to May 2001 during Research Project. C-PMNHIBio(311). Data was collected on physico-chemical properties of the Fresh water and the Algal Flora. The fluctuations of temperature, pH, Dissolved oxygen, salinity, T.D.S., Total hardness etc., were studied. From algal flora, a total. 291 algal species were found to belong to 108 genera 10 Phylum. From Cyanophyta, 68 species belongs to 21 genera with 23.37%, Volvocophyta 107 species belongs to 40 genera with 36.77%, Chlorophyta 18 species belongs to 13 genera with 6.19%, Bacillariophyta 66 species 19 genera with 22.67%, Chrysophyta 3 species belongs to 2 genera with 1.03%, Xanthophyta 5 species belongs to 5 genera with 1.72%, Vaucheriophyta 1 species belongs to 1 genus with 0.34%, Euglenophyta 16 species belongs to 4 genera with 1.72%, Dinophyta 5 species belongs to 2 genera with 1.72%, Charophyta 2 species belong to 1 genus with 0.7%, were recorded and classified by latest classification according to Shameel (2001). The present work shows the changes in physico-chemical factor along with algal flora in Rawal Dam during collection period and co-relation of different factors. (author)

Macroalgal diversity of Santa Cesarea-Castro (Salento Peninsula, southeastern Italy

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Antonella Bottalico

2016-11-01

Full Text Available The benthic macroalgal flora from the eastern Ionian coastal area of the Peninsula Salentina is scarcely studied. This study gives a contribution to the knowledge on its biodiversity in this area, which also includes marine caves, and the geographical distribution of some interesting species. A total of 174 macroalgae (119 Rhodophyta, 27 Ochrophyta, and 28 Chlorophyta were identified. Six species are first records for the region, one of which, Liagora ceranoides, represents a new record for the Italian flora. The vegetation of most of the wave-exposed rocky substrata, as well as of the two sulphureous caves at Santa Cesarea Terme is characterised by extensive populations of Corallinales. The chorological spectrum of the flora shows a high occurrence of Indo-Pacific and Circumtropical elements, thus resulting more similar to that of floras of the Greek Ionian Sea.

Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic.

Science.gov (United States)

Scherner, Fernando; Horta, Paulo Antunes; de Oliveira, Eurico Cabral; Simonassi, José Carlos; Hall-Spencer, Jason M; Chow, Fungyi; Nunes, José Marcos C; Pereira, Sonia Maria Barreto

2013-11-15

Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (-38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages. Copyright © 2013 Elsevier Ltd. All rights reserved.

THE CLADOPHORA COMPLEX (CHLOROPHYTA) - NEW VIEWS BASED ON 18S RIBOSOMAL-RNA GENE-SEQUENCES

NARCIS (Netherlands)

BAKKER, FT; OLSEN, JL; STAM, WT; VANDENHOEK, C

1994-01-01

Evolutionary relationships among species traditionally ascribed to the Siphonocladales/Cladophorales have remained unclear due to a lack of phylogenetically informative characters and extensive morphological plasticity resulting in morphological convergence. This study explores some of the diversity

The Cladophora complex (Chlorophyta): new views based on 18S rRNA gene sequences

NARCIS (Netherlands)

Bakker, F.T.; Olsen, J.L.; Stam, W.T.; Hoek, van den J.

1994-01-01

Evolutionary relationships among species traditionally ascribed to the Siphonocladales/Cladophorales have remained unclear due to a lack of phylogenetically informative characters and extensive morphological plasticity resulting in morphological convergence. This study explores some of the diversity

The epiphytic microbiota of the globally widespread macroalga Cladophora glomerata (Chlorophyta, Cladophorales).

Science.gov (United States)

Zulkifly, Shahrizim; Hanshew, Alissa; Young, Erica B; Lee, Philip; Graham, Melissa E; Graham, Michael E; Piotrowski, Michael; Graham, Linda E

2012-09-01

The filamentous chlorophyte Cladophora produces abundant nearshore populations in marine and freshwaters worldwide, often dominating periphyton communities and producing nuisance growths under eutrophic conditions. High surface area and environmental persistence foster such high functional and taxonomic diversity of epiphytic microfauna and microalgae that Cladophora has been labeled an ecological engineer. We tested the hypotheses that (1) Cladophora supports a structurally and functionally diverse epiphytic prokaryotic microbiota that influences materials cycling and (2) mutualistic host-microbe interactions occur. Because previous molecular sequencing-based analyses of the microbiota of C. glomerata found as western Lake Michigan beach drift had identified pathogenic associates such as Escherichia coli, we also asked if actively growing lentic C. glomerata harbors known pathogens. We used 16S rRNA gene amplicon pyrosequencing to examine the microbiota of C. glomerata of Lake Mendota, Dane, Wisconsin, United States, during the growing season of 2011, at the genus- or species-level to infer functional phenotypes. We used correlative scanning electron and fluorescence microscopy to describe major prokaryotic morphotypes. We found microscopic evidence for diverse bacterial morphotypes, and molecular evidence for ca. 100 distinct sequence types classifiable to genus at the 80% confidence level or species at the 96-97% level within nine bacterial phyla, but not E. coli or related human pathogens. We inferred that bacterial epiphytes of lentic C. glomerata have diverse functions in materials cycling, with traits that indicate the occurrence of mutualistic interactions with the algal host.

Bacteria-induced morphogenesis of Ulva intestinalis and Ulva mutabilis (Chlorophyta): a contribution to the lottery theory.

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Ghaderiardakani, Fatemeh; Coates, Juliet C; Wichard, Thomas

2017-08-01

The green marine macroalgae of the class Ulvophyceae (Ulvophytes) are common algae distributed worldwide particularly in intertidal areas, which play a key role in aquatic ecosystems. They are potentially valuable resources for food, animal feed and fuel but can also cause massive nuisance blooms. Members of Ulvaceae, like many other seaweeds, harbour a rich diversity of epiphytic bacteria with functions related to host growth and morphological development. In the absence of appropriate bacterially derived signals, germ cells of the genus Ulva develop into 'atypical' colonies consisting of undifferentiated cells with abnormal cell walls. This paper examines the specificity of bacteria-induced morphogenesis in Ulva, by cross-testing bacteria isolated from several Ulva species on two Ulva species, the emerging model system Ulva mutabilis and the prominent biofouler species Ulva intestinalis. We show that pairs of bacterial strains isolated from species other than U. mutabilis and U. intestinalis can fully rescue axenic plantlets generated either from U. mutabilis or U. intestinalis gametes. This laboratory-based study demonstrates that different compositions of microbial communities with similar functional characteristics can enable complete algal morphogenesis and thus supports the 'competitive lottery' theory for how symbiotic bacteria drive algal development. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Interactions between marine facultative epiphyte Chlamydomonas sp. (Chlamydomonadales, Chlorophyta) and ceramiaceaen algae (Rhodophyta).

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Klochkova, Tatyana A; Cho, Ga Youn; Boo, Sung Min; Chung, Ki Wha; Kim, Song Ja; Kim, Gwang Hoon

2008-07-01

Previously unrecorded marine Chlamydomonas that grew epiphytic on ceramiaceaen algae was collected from the western coast of Korea and isolated into a unialgal culture. The isolate was subjected to 18S rDNA phylogenetic analysis as well as ultrastructure and life cycle studies. It had an affinity with the marine Chlamydomonas species and was less related to freshwater/terrestrial representatives of this genus. It had flagella shorter than the cell body two-layered cell wall with striated outer surface and abundant mucilaginous material beneath the innermost layer and no contractile vacuoles. This alga grew faster in mixed cultures with ceramiaceaen algae rather than in any tested unialgal culture condition; the cells looked healthier and zoosporangia and motile flagellated vegetative cells appeared more often. These results suggested that this Chlamydomonas might be a facultative epiphyte benefiting from its hosts. Several ceramiaceaen algae were tested as host plants. Meanwhile, cell deformation or collapse of the whole thallus was caused to Aglaothamnion byssoides, and preliminary study suggested that a substance released from Chlamydomonas caused the response. This is first report on harmful epiphytic interactions between Chlamydomonas species and red ceramiaceaen algae.

Carbon Partitioning in Green Algae (Chlorophyta and the Enolase Enzyme

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Jürgen E. W. Polle

2014-08-01

Full Text Available The exact mechanisms underlying the distribution of fixed carbon within photoautotrophic cells, also referred to as carbon partitioning, and the subcellular localization of many enzymes involved in carbon metabolism are still unknown. In contrast to the majority of investigated green algae, higher plants have multiple isoforms of the glycolytic enolase enzyme, which are differentially regulated in higher plants. Here we report on the number of gene copies coding for the enolase in several genomes of species spanning the major classes of green algae. Our genomic analysis of several green algae revealed the presence of only one gene coding for a glycolytic enolase [EC 4.2.1.11]. Our predicted cytosolic localization would require export of organic carbon from the plastid to provide substrate for the enolase and subsequent re-import of organic carbon back into the plastids. Further, our comparative sequence study of the enolase and its 3D-structure prediction may suggest that the N-terminal extension found in green algal enolases could be involved in regulation of the enolase activity. In summary, we propose that the enolase represents one of the crucial regulatory bottlenecks in carbon partitioning in green algae.

Heavy metal concentrations in marine green, brown, and red seaweeds from coastal waters of Yemen, the Gulf of Aden

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Al-Shwafi, Nabil A.; Rushdi, Ahmed I.

2008-08-01

The purpose of this study was to investigate the concentration levels of heavy metals in different species of the main three marine algal divisions from the Gulf of Aden coastal waters, Yemen. The divisions included Chlorophyta—green plants ( Halimeda tuna, Rhizoclonium kochiamum, Caldophora koiei, Enteromorpha compressa, and Caulerpa racemosa species), Phaeophyta—brown seaweeds ( Padina boryana, Turbinaria elatensis, Sargassum binderi, Cystoseira myrica, and Sargassum boveanum species), and Rhodophyta—red seaweeds ( Hypnea cornuta, Champia parvula, Galaxaura marginate, Laurencia paniculata, Gracilaria foliifere, and species). The heavy metals, which included cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), Iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), zinc (Zn), and vanadium (V) were measured by Atomic Absorption Spectrophotometer (AAs). The concentrations of heavy metals in all algal species are in the order of Fe >> Cu > Mn > Cr > Zn > Ni > Pb > Cd > V > Co. The results also showed that the uptake of heavy metals by different marine algal divisions was in the order of Chlorophyta > Phaeophyta > Rhodophyta. These heavy metals were several order of magnitude higher than the concentrations of the same metals in seawater. This indicates that marine alga progressively uptake heavy metals from seawater.

Morphological features of the species of the genus Chlamydomonas s.l. (Chlorophyta from various molecular clades

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Maria N. Pavlovska

2012-03-01

Full Text Available The morphology of 78 authentic strains from 5 clades into culture condition was investigated. The complex of phenotype features was established. Such features as: type of mucilage and their origin, mucilage collapse under methylene blue, saving papilla and stigma in not motile stage, extracellular matrix formation inside cell wall, the way of sporangium break, pyrenoid and stigma habit before cell division, cell shape, chloroplast morphology. Diagnostic features for determination of taxa on clades level are discussed.

Unraveling the Photoprotective Response of Lichenized and Free-Living Green Algae (Trebouxiophyceae, Chlorophyta to Photochilling Stress

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Fátima Míguez

2017-07-01

Full Text Available Lichens and free-living terrestrial algae are widespread across many habitats and develop successfully in ecosystems where a cold winter limits survival. With the goal of comparing photoprotective responses in free-living and lichenized algae, the physiological responses to chilling and photochilling conditions were studied in three lichens and their isolated algal photobionts together as well as in a fourth free-living algal species. We specifically addressed the following questions: (i Are there general patterns of acclimation in green algae under chilling and photochilling stresses? (ii Do free-living algae exhibit a similar pattern of responses as their lichenized counterparts? (iii Are these responses influenced by the selection pressure of environmental conditions or by the phylogenetic position of each species? To answer these questions, photosynthetic fluorescence measurements as well as pigment and low molecular weight carbohydrate pool analyses were performed under controlled laboratory conditions. In general, photochemical efficiency in all free-living algae decreased with increasing duration of the stress, while the majority of lichens maintained an unchanged photochemical activity. Nevertheless, these patterns cannot be generalized because the alga Trebouxia arboricola and the lichen Ramalina pollinaria (associated with Trebouxia photobionts both showed a similar decrease in photochemical efficiency. In contrast, in the couple Elliptochloris bilobata-Baeomyces rufus, only the algal partner exhibited a broad physiological performance under stress. This study also highlights the importance of the xanthophyll cycle in response to the studied lichens and algae to photochilling stress, while the accumulation of sugars was not related to cold acclimation, except in the alga E. bilobata. The differences in response patterns detected among species can be mainly explained by their geographic origin, although the phylogenetic position should

Seaweed temporal distribution in southeast coast of Peninsular Malaysia and isolation of endophytic fungi

Science.gov (United States)

Zainee, Nur Farah Ain; Ismail, Ahmad; Ibrahim, Nazlina; Ismail, Asmida

2018-04-01

Temporal study of seaweeds was carried out between on February 2015 and November 2015 at Kampung Jawa Darat and Kampung Sungai Buntu at Pengerang, Johor, Malaysia. The research objectives were to study the diversity of seaweed and to determine the presence of fungal endophyte in the seaweed. The diversity of seaweed in the sampling site was calculated by using quadrat with 25 meter line transect by 3 replication for each site. The specimen were identified and processed in laboratory and kept for reference in the Algae Herbarium, Universiti Kebangsaan Malaysia. The specimen for fungal endophyte isolation was collected randomly by choosing the complete thallus, transferred into sterile zip-lock plastic bag and kept in freezer until used. From this study, a total of 29 species have been successfully identified including 12 species of Chlorophyta, 2 species of Phaeophyta and 14 species of Rhodophyta. From February to November 2015, the number of species highly varied and a significant change in community structure was noted. Kampung Sungai Buntu shows the highest diversity throughout the study compared to Kampung Jawa Darat. Eighteen seaweed species were screened for the presence of fungal endophyte, Sargassum polycystum shows the highest number of fungal endophyte. This study documented the seaweed diversity in two sites at Pengerang, Johor that accommodates fungal endophytes.

Biological Soil Crusts of Arctic Svalbard—Water Availability as Potential Controlling Factor for Microalgal Biodiversity

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Nadine Borchhardt

2017-08-01

Full Text Available In the present study the biodiversity of biological soil crusts (BSCs formed by phototrophic organisms were investigated on Arctic Svalbard (Norway. These communities exert several important ecological functions and constitute a significant part of vegetation at high latitudes. Non-diatom eukaryotic microalgal species of BSCs from 20 sampling stations around Ny-Ålesund and Longyearbyen were identified by morphology using light microscopy, and the results revealed a high species richness with 102 species in total. 67 taxa belonged to Chlorophyta (31 Chlorophyceae and 36 Trebouxiophyceae, 13 species were Streptophyta (11 Klebsormidiophyceae and two Zygnematophyceae and 22 species were Ochrophyta (two Eustigmatophyceae and 20 Xanthophyceae. Surprisingly, Klebsormidium strains belonging to clade G (Streptophyta, which were so far described from Southern Africa, could be determined at 5 sampling stations. Furthermore, comparative analyses of Arctic and Antarctic BSCs were undertaken to outline differences in species composition. In addition, a pedological analysis of BSC samples included C, N, S, TP (total phosphorus, and pH measurements to investigate the influence of soil properties on species composition. No significant correlation with these chemical soil parameters was confirmed but the results indicated that pH might affect the BSCs. In addition, a statistically significant influence of precipitation on species composition was determined. Consequently, water availability was identified as one key driver for BSC biodiversity in Arctic regions.

Biological Soil Crusts of Arctic Svalbard-Water Availability as Potential Controlling Factor for Microalgal Biodiversity.

Science.gov (United States)

Borchhardt, Nadine; Baum, Christel; Mikhailyuk, Tatiana; Karsten, Ulf

2017-01-01

In the present study the biodiversity of biological soil crusts (BSCs) formed by phototrophic organisms were investigated on Arctic Svalbard (Norway). These communities exert several important ecological functions and constitute a significant part of vegetation at high latitudes. Non-diatom eukaryotic microalgal species of BSCs from 20 sampling stations around Ny-Ålesund and Longyearbyen were identified by morphology using light microscopy, and the results revealed a high species richness with 102 species in total. 67 taxa belonged to Chlorophyta (31 Chlorophyceae and 36 Trebouxiophyceae), 13 species were Streptophyta (11 Klebsormidiophyceae and two Zygnematophyceae) and 22 species were Ochrophyta (two Eustigmatophyceae and 20 Xanthophyceae). Surprisingly, Klebsormidium strains belonging to clade G (Streptophyta), which were so far described from Southern Africa, could be determined at 5 sampling stations. Furthermore, comparative analyses of Arctic and Antarctic BSCs were undertaken to outline differences in species composition. In addition, a pedological analysis of BSC samples included C, N, S, TP (total phosphorus), and pH measurements to investigate the influence of soil properties on species composition. No significant correlation with these chemical soil parameters was confirmed but the results indicated that pH might affect the BSCs. In addition, a statistically significant influence of precipitation on species composition was determined. Consequently, water availability was identified as one key driver for BSC biodiversity in Arctic regions.

Gametangial characteristics in the sexual reproduction of Halimeda macroloba Decaisne (Chlorophyta: Halimedaceae

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Jaruwan Mayakun1

2012-04-01

Full Text Available Halimeda macroloba Decaisne is a reef builder that provides habitats for many marine organisms and is importantfor the production of calcium carbonate sediments. This species is one of the most common and abundant algae in tropicalregions of the Indo-Pacific Ocean. However, the trigger for reproduction of H. macroloba is not well understood. We haveexamined some environmental factors that might trigger reproduction and determined the gametangial characteristics of H.macroloba. The peak seasonal reproduction of H. macroloba occurred within only a 3-month period (May-July. Nutrientand salinity were found to have triggered reproduction. Gametangial clusters were produced along the outer margin of segmentsand the gametophores had a long stipe and were dichotomously branched at their distal end. Divided and sessilegametangia were observed. This description of the variable gametangial morphology of H. macroloba is reported for the firsttime.

Regulation of gametogenesis and zoosporogenesis in Ulva linza (Chlorophyta: comparison with Ulva mutabilis and potential for laboratory culture

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Eleanor Fay Vesty

2015-01-01

Full Text Available Green Ulvophyte macroalgae represent attractive model systems for understanding growth, development and evolution. They are untapped resources for food, fuel and high-value compounds, but can also form nuisance blooms. To fully analyse green seaweed morphogenesis, controlled laboratory-based culture of these organisms is required. To date, only a single Ulvophyte species, Ulva mutabilis Føyn, has been manipulated to complete its whole life cycle in laboratory culture and to grow continuously under axenic conditions. Such cultures are essential to address multiple key questions in Ulva development and in algal-bacterial interactions. Here we show that another Ulva species, U. linza, with a broad geographical distribution, has the potential to be grown in axenic culture similarly to U. mutabilis. Ulva linza can be reliably induced to sporulate (form gametes and zoospores in the laboratory, by cutting the relevant thallus tissue into small pieces and removing extracellular inhibitors (sporulation and swarming inhibitors. The germ cells work as an ideal feed stock for standardized algae cultures.The requirement of U. linza for bacterial signals to induce its normal morphology (particularly of the rhizoids appears to have a species-specific component. The axenic cultures of these two species pave the way for future comparative studies of algal-microbial interactions.

Regulation of gametogenesis and zoosporogenesis in Ulva linza (Chlorophyta): comparison with Ulva mutabilis and potential for laboratory culture

Science.gov (United States)

Vesty, Eleanor F.; Kessler, Ralf W.; Wichard, Thomas; Coates, Juliet C.

2015-01-01

Green Ulvophyte macroalgae represent attractive model systems for understanding growth, development, and evolution. They are untapped resources for food, fuel, and high-value compounds, but can also form nuisance blooms. To fully analyze green seaweed morphogenesis, controlled laboratory-based culture of these organisms is required. To date, only a single Ulvophyte species, Ulva mutabilis Føyn, has been manipulated to complete its whole life cycle in laboratory culture and to grow continuously under axenic conditions. Such cultures are essential to address multiple key questions in Ulva development and in algal–bacterial interactions. Here we show that another Ulva species, U. linza, with a broad geographical distribution, has the potential to be grown in axenic culture similarly to U. mutabilis. U. linza can be reliably induced to sporulate (form gametes and zoospores) in the laboratory, by cutting the relevant thallus tissue into small pieces and removing extracellular inhibitors (sporulation and swarming inhibitors). The germ cells work as an ideal feed stock for standardized algae cultures. The requirement of U. linza for bacterial signals to induce its normal morphology (particularly of the rhizoids) appears to have a species-specific component. The axenic cultures of these two species pave the way for future comparative studies of algal–microbial interactions. PMID:25674100

Growth rate and calcium carbonate accumulation of Halimeda macrolobaDecaisne (Chlorophyta: Halimedaceae in Thai waters

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Jaruwan Mayakun

2014-08-01

Full Text Available Halimeda macroloba Decaisne can utilize the CO2 used for carbon fixation in photosynthesis and use bicarbonate as the main carbon source for calcification. Although Halimeda has been recognized as a carbon sink species, the calcium accumulation of Halimeda species in Thai waters remain poorly understood. In this study, the highest density of H. macroloba was 26 thalli/m2 and Halimeda quickly produced 1-2 new segments/thallus/day or 20.1 mg dry weight/thallus/day. Its calcium carbonate accumulation rate was 16.6 mg CaCO3 /thallus/day, or 82.46 % per thallus. In Thailand, however, only three scientific papers of growth rate and CaCO3 accumulation rate of H. macroloba have been found and collected. Of these records, the mean density was 26-104 thalli/m2 . The growth rate of H. macroloba was around 1-2 mg dry weight/day and the CaCO3 accumulation rate varied around 41-91%. Thus, Halimeda has a great potential to decrease the carbon dioxide concentration in the ocean.

Production and characterization of antimicrobial active substance ...

African Journals Online (AJOL)

Linnaeus) Lamouroux; Ulva fasciata Delile and Sargassum vulgare C. Agardh] belonging to Rhodophyta, Chlorophyta and Phaeophyceae, respectively, were collected seasonally in 2007 to 2008 from Abu-Qir bay (Alexandria, Egypt).

Alimentação de Limnoperna fortunei (Dunker 1857: taxas de filtração com ênfase ao uso de Cyanobacteria- DOI: 10.4025/actascibiolsci.v26i4.1523 Feeding of Limnoperna fortunei (Dunker 1857: filtration rates with emphasis on Cyanobacteria use - DOI: 10.4025/actascibiolsci.v26i4.1523

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Mônica de Cassia Souza Campos

2004-04-01

Full Text Available Limnoperna fortunei é uma espécie invasora na América do Sul que, devido ao seu crescimento excessivo, tornou-se um sério problema para o ambiente e para os setores usuários de água bruta. L. fortunei é um molusco filtrador que se alimenta de fitoplâncton e outras partículas suspensas. Moluscos filtradores são grandes bioacumuladores de toxinas. Desta forma, L. fortunei apresenta um potencial de bioacumulação e transferência na cadeia trófica de cianotoxinas. Neste estudo, experimentos in vitro demonstraram que L. fortunei é capaz de alimentar-se de espécies de Cyanobacteria potencialmente tóxicas, Microcystis viridis e Pseudanabaena sp. As taxas de filtração foram 17,20 e 24,52mL.mgPS-1.h-1, respectivamente, sendo similares à encontrada para a Chlorophyta Selenastrum capricornutum – 11,91mL.mgPS 1.h-1. Os resultados indicaram que a bioacumulação de cianotoxinas por L. fortunei pode tornar-se um problema futuro visto as grandes densidades que esses organismos atingem e a sua utilização como item alimentar de peixesLimnoperna fortunei is an invasive species in South America. The massive growth of this species became a great problem for environment and for the companies that use raw water. Limnoperna fortunei is a filter-feeding mollusk that feed on phytoplankton and other suspended particles. Filtering mollusks are great toxin bioaccumulators. Then L. fortunei has a potential cyanotoxin bioaccumulation and transfer in the food chain. In this study, in vitro experiments showed that L. fortunei is able to feed on Cyanobacteria toxic species, Microcystis viridis and Pseudanabaena sp. The filtration rates were 17.20 and 24.52mL.mgDW-1.h-1, respectively. They were similar as for the Chlorophyta Selenastrum capricornutum – 11.91mL.mgDW-1.h-1. Results showed that cyanotoxins bioaccumulation by Limnoperna fortunei could be a future problem because of the high densities reached by these organisms and their feeding utilization

African Journal of Biotechnology - Vol 10, No 12 (2011)

African Journals Online (AJOL)

Studies on the analgesic and anti-inflammatory activities of Sargassum swartzii ... and Ulva reticulata Forsskal (Chlorophyta) in experiment animal models ... Metabolic flux distribution and mathematical models for dynamic simulation of carbon ...

The chlorococcalean alga Chlorella in animal nutrition: a review

Czech Academy of Sciences Publication Activity Database

Kotrbáček, V.; Doubek, J.; Doucha, Jiří

2015-01-01

Roč. 27, č. 6 (2015), s. 2173-2180 ISSN 0921-8971 Institutional support: RVO:61388971 Keywords : Chlorella * Chlorophyta * Feed supplement Subject RIV: EE - Microbiology, Virology Impact factor: 2.372, year: 2015

Endangered Species Day | Endangered Species Coalition

Science.gov (United States)

Annual Top 10 Report Protecting the Endangered Species Act Wildlife Voices Stand for Wolves Endangered Campaigns Wildlife Voices Protecting the Endangered Species Act Annual Top 10 Report Endangered Species Day Stand for Wolves Vanishing BOOK: A Wild Success The Endangered Species Act at 40 Endangered Species The

Observations on feeding behaviour and survival rates in the estuarine calanoid copepods Acartia spinicauda and Heliodiaptomus cinctus (Crustacea: Copepoda: Calanoida)

Digital Repository Service at National Institute of Oceanography (India)

Srivastava, Y.; Fernandes, Brenda; Goswami, S.C.; Goswami, U.; Achuthankutty, C.T.

of Tetraselmis gracilis (Chlorophyta) and Skeletonema costatum (Bacillariophyta), whereas, adults of H. cinctus were fed on five different combinations of phytoplankton feed. Total hourly differences in pigment concentrations indicate that A. spinicauda preferred...

Evaluation of a recirculating pond system for rearing juvenile freshwater mussels at White Sulphur Springs National Fish Hatchery, West Virginia, U.S.A.

Science.gov (United States)

Mummert, A.; Newcomb, T.J.; Neves, R.J.; Parker, B.

2006-01-01

A recirculating double-pond system at White Sulphur Springs National Fish Hatchery in West Virginia, U.S.A., was evaluated for suitability for culturing juvenile freshwater mussels. Newly metamorphosed juveniles of Villosa iris and Lampsilis fasciola were placed in the system, and their growth and survival were evaluated for 94 days. Throughout the study, parameters of water quality remained within ranges suitable for mussel survival. Planktonic algal densities in the pond system ranged from 2850 to 6892 cells/ml. Thirty-seven algal taxa were identified, primarily green algae (Chlorophyta), diatoms (Bacillariophyceae), and blue-green algae (Cyanoprokaryota). Over the culture period, juveniles of L. fasciola experienced significantly lower (p fasciola may indicate a failure of the flow-through pond environment to meet its habitat requirements or that variable microhabitat conditions within culture containers existed. Growth did not differ significantly between the species (p = 0.13). Survival of V. iris and growth of both species were similar to previous trials to culture juvenile mussels. Survival rates as high as 66.4% at 93 days for V. iris suggest that juveniles of some riverine species can be successfully cultured in a recirculating pond environment.

RESEARCH ON THE ENVIRONMENTAL QUALITY IN BRATIA RIVER

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Alina - Mihaela Truţă

2017-12-01

Full Text Available The main purpose of the study was to determine the quality of Bratia River. The present paper was based on the bibliographic material as well as the field research carried out during 2016-2017. The research objectives were the following: identification of qualitative and quantitative structure of phytobenthic biocenoses in the established monitoring points; determination of the phytoplankton algae families in the monitoring stations; identification of the structure of benthic biocenoses in the monitoring points; establishing saprobity indices for each species identified and incorporation of the monitoring sections into the appropriate saprobity class; determining the quality of Bratia River according to the Water Framework Directive 2000/60/EU. We have identified 54 species in the phytobenthonic samples, grouped in three phyla: Cyanobacteria, Bacillariophyta and Chlorophyta. We have also identified 47 species in the structure of benthic zoocenosis belonging to 25 families from 8 genera. The main benthic invertebrate groups in the Bratia River were: Ephemeroptera, Plecoptera, Chironomidae, Trichoptera, and Gammaridae. Oboarele Mari and Gămăceşti recorded a high quality ecological status, while Berevoiesti station had a good ecological status.

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.

Strong Endemism of bloom-forming tubular Ulva in Indian West Coast, with description of Ulva paschima Sp. Nov. (Ulvales, Chlorophyta).

Science.gov (United States)

Bast, Felix; John, Aijaz Ahmad; Bhushan, Satej

2014-01-01

Ulva intestinalis and Ulva compressa are two bloom-forming morphologically-cryptic species of green seaweeds widely accepted as cosmopolitan in distribution. Previous studies have shown that these are two distinct species that exhibit great morphological plasticity with changing seawater salinity. Here we present a phylogeographic assessment of tubular Ulva that we considered belonging to this complex collected from various marine and estuarine green-tide occurrences in a ca. 600 km stretch of the Indian west coast. Maximum Likelihood and Bayesian Inference phylogenetic reconstructions using ITS nrDNA revealed strong endemism of Indian tubular Ulva, with none of the Indian isolates forming part of the already described phylogenetic clades of either U. compressa or U. intestinalis. Due to the straightforward conclusion that Indian isolates form a robust and distinct phylogenetic clade, a description of a new bloom-forming species, Ulva paschima Bast, is formally proposed. Our phylogenetic reconstructions using Neighbor-Joining method revealed evolutionary affinity of this new species with Ulva flexuosa. This is the first molecular assessment of Ulva from the Indian Subcontinent.

Separation, identification and quantification of photosynthetic ...

African Journals Online (AJOL)

Thirty one photosynthetic pigments (chlorophylls, carotenoids and degradation products) from the seaweeds, Codium dwarkense, (Chlorophyta), , Laurencia obtusa , (Rhodophyta) and , Lobophora variegata, (Phaeophyta), were separated in a single-step procedure by reversed phase high-performance liquid ...

Screening of seaweeds in the East China Sea as potential bio-monitors of heavy metals.

Science.gov (United States)

Pan, Yaoru; Wernberg, Thomas; de Bettignies, Thibaut; Holmer, Marianne; Li, Ke; Wu, Jiaping; Lin, Fang; Yu, Yan; Xu, Jiang; Zhou, Chaosheng; Huang, Zhixing; Xiao, Xi

2018-03-30

Seaweeds are good bio-monitors of heavy metal pollution and have been included in European coastal monitoring programs. However, data for seaweed species in China are scarce or missing. In this study, we explored the potential of seaweeds as bio-monitor by screening the natural occurring seaweeds in the "Kingdom of seaweed and shellfish" at Dongtou Islands, the East China Sea. Totally, 12 seaweed species were collected from six sites, with richness following the sequence of Rhodophyta > Phaeophyta > Chlorophyta. The concentration of heavy metals (Cu, Cr, Ni, Zn, Pb, Cd, As) in the seaweeds was determined, and the bioaccumulation coefficient was calculated. A combination of four seaweeds, Pachydictyon coriaceum, Gelidium divaricatum, Sargassum thunbergii, and Pterocladiella capillacea, were proposed as bio-monitors due to their high bioaccumulation capabilities of specific heavy metals in the East China Sea and hence hinted the importance of using seaweed community for monitoring of pollution rather than single species. Our results provide first-hand data for the selection of bio-monitor species for heavy metals in the East China Sea and contribute to selection of cosmopolitan bio-monitor communities over geographical large area, which will benefit the establishment of monitoring programs for coastal heavy metal contamination.

New records of benthic marine algae and Cyanobacteria for Costa Rica, and a comparison with other Central American countries

Science.gov (United States)

Bernecker, Andrea; Wehrtmann, Ingo S.

2009-09-01

We present the results of an intensive sampling program carried out from 2000 to 2007 along both coasts of Costa Rica, Central America. The presence of 44 species of benthic marine algae is reported for the first time for Costa Rica. Most of the new records are Rhodophyta (27 spp.), followed by Chlorophyta (15 spp.), and Heterokontophyta, Phaeophycea (2 spp.). Overall, the currently known marine flora of Costa Rica is comprised of 446 benthic marine algae and 24 Cyanobacteria. This species number is an under estimation, and will increase when species of benthic marine algae from taxonomic groups where only limited information is available (e.g., microfilamentous benthic marine algae, Cyanobacteria) are included. The Caribbean coast harbors considerably more benthic marine algae (318 spp.) than the Pacific coast (190 spp.); such a trend has been observed in all neighboring countries. Compared to other Central American countries, Costa Rica has the highest number of reported benthic marine algae; however, Panama may have a similarly high diversity after unpublished results from a Rhodophyta survey (Wysor, unpublished) are included. Sixty-two species have been found along both the Pacific and Caribbean coasts of Costa Rica; we discuss this result in relation to the emergence of the Central American Isthmus.

Flora planctónica de laguna Lagartos, Quintana Roo Planktonic flora from Lagartos Lagoon, Quintana Roo

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Viridiana Margarita Nava-Ruiz

2012-09-01

Full Text Available Se presenta una lista de la flora planctónica de la laguna Lagartos, basada en la observación de muestras superficiales obtenidas entre noviembre de 2007 a septiembre de 2008. Las muestras se recolectaron con una botella Van Dorn de 2 litros en la parte central de la laguna; se registraron 67 taxa: 28 Bacillariophyta, 22 Cyanoprokaryota, 7 Chlorophyta, 6 Dinoflagellata, 2 Euglenophyta y 2 Cryptophyta. Las cianofitas dominaron durante todo el periodo de estudio, con una contribución mayor al 80% de la abundancia total del fitoplancton. Son nuevos registros para México 13 especies: Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum, Planktolyngbya contorta, Rhodomonas minuta, Amphidinium massartii, Ensiculifera cf. loeblichii, Heterocapsa cf. pseudotriquetra, Prorocentrum cassubicum, Licmophora normaniana, Fistulifera saprophila y Amphora richardiana. Todos los taxa listados se ilustran con microfotografías.The planktonic flora from Lagartos Lagoon, Quintana Roo, was examined based on the observation of samples collected from November 2007 to September 2008. The superficial samples were collected with a Van Dorn bottle of 2 L, in the core part of the lagoon. A total of 67 taxa were identified: 28 Bacillariophyta, 22 Cyanoprokaryota, 7 Chlorophyta, 6 Dinoflagellata, 2 Euglenophyta and 2 Cryptophyta. Nevertheless, the blue green algae dominated during all study period, with more of 80% to the total abundance of the phytoplankton. The species Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum, Planktolyngbya contorta, Rhodomonas minuta, Amphidinium massartii, Ensiculifera cf. loeblichii, Heterocapsa cf. pseudotriquetra, Prorocentrum cassubicum, Licmophora normaniana, Fistulifera saprophila and Amphora richardiana were recorded for the first time in Mexico. All the taxa are illustrated with microphotographs.

Time spans and spacers: Molecular phylogenetic explorations in the Cladophora complex (Chlorophyta) from the perspective of rDNA gene and spacer sequences

OpenAIRE

Bakker, Frederik Theodoor

1995-01-01

In this study, phylogenetic relationships among genera, species and biogeographic representatives of single Cladophora species within the Cladophorales were analyzed using rDNA gene and spacer sequences. Based on phylogenetic analysis of 18S rRNA gene sequences, the Cladophora complex is shown to be paraphyletic with respect to Cladophora species and includes several genera shich werde traditionally ascribed to the Siphonocladales (Chapter 3). ... Zie: Summary/Samenvatting

Inhibition of the development of pathogenic fungi by extracts of some ...

African Journals Online (AJOL)

The different marine algae belonged to Chlorophyta (Enteromorpha prolifera and Ulva reticulata), Phaeophyta (Cystoseira myrica, Padina pavonica, Sargassum portieriatum and Turbinaria triquetra) and Rhodophyta (Gracilaria multipartita). Algal extraction was achieved successively by using petroleum ether, diethyl ether, ...

A Simple Method to Decode the Complete 18-5.8-28S rRNA Repeated Units of Green Algae by Genome Skimming.

Science.gov (United States)

Lin, Geng-Ming; Lai, Yu-Heng; Audira, Gilbert; Hsiao, Chung-Der

2017-11-06

Green algae, Chlorella ellipsoidea , Haematococcus pluvialis and Aegagropila linnaei (Phylum Chlorophyta) were simultaneously decoded by a genomic skimming approach within 18-5.8-28S rRNA region. Whole genomic DNAs were isolated from green algae and directly subjected to low coverage genome skimming sequencing. After de novo assembly and mapping, the size of complete 18-5.8-28S rRNA repeated units for three green algae were ranged from 5785 to 6028 bp, which showed high nucleotide diversity (π is around 0.5-0.6) within ITS1 and ITS2 (Internal Transcribed Spacer) regions. Previously, the evolutional diversity of algae has been difficult to decode due to the inability design universal primers that amplify specific marker genes across diverse algal species. In this study, our method provided a rapid and universal approach to decode the 18-5.8-28S rRNA repeat unit in three green algal species. In addition, the completely sequenced 18-5.8-28S rRNA repeated units provided a solid nuclear marker for phylogenetic and evolutionary analysis for green algae for the first time.

Identification of toxigenic Cyanobacteria of the genus Microcystis in the Curonian Lagoon (Baltic Sea)

Science.gov (United States)

Belykh, O. I.; Dmitrieva, O. A.; Gladkikh, A. S.; Sorokovikova, E. G.

2013-02-01

In 2002-2008, seasonal (April-November) monitoring of the phytoplankton in the Russian part of the Curonian Lagoon at five fixed sites was performed. A total of 91 Cyanobacteria, 100 Bacillariophyta, 280 Chlorophyta, 21 Cryptophyta, and 24 Dinophyta species were found. Six potentially toxic species of cyanobacteria: Aphanizomenon flos-aquae, Anabaena sp., Microcystis aeruginosa, M. viridis, M. wesenbergii, and Planktothrix agardhii dominated the phytoplankton biomass and caused water blooms. The seasonal average phytoplankton biomass ranged from 30 to 137 g/m3. The cyanobacteria's biomass varied from 10 to 113 g/m3 forming 30-82% of the total with a mean of 50%. With the aid of genetic markers (microcystin ( mcy) and nodularin synthetases), six variants of the microcystin-producing gene mcyE from the genus Microcystis were identified. Due to the intensive and lengthy blooms of potentially toxic and toxigenic cyanobacteria, the environmental conditions in the Curonian Lagoon appear unfavorable. The water should be monitored for cyanotoxins with analytical methods in order to determine if the area is safe for recreational use.

Antibacterial, antioxidant and cytotoxic activities of extracts from the ...

African Journals Online (AJOL)

Unicellular green algal strains, identified as Cosmarium (Chlorophyta), were isolated from Ain-Echeffa hot spring in north Tunisia. Different extracts (methanol, hexane, acetone, acetone: methanol and water) obtained from both biomass and extracellular polysaccharides (EPS) were evaluated for their antibacterial, ...

Antalya İli Batı Kıyıları (Lara – Kalkan'nın Ekonomik Amaçlı Deniz Algleri

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Furkan DURUCAN

2014-12-01

Abstract: This study has been carried out with seasonal samples in five stations in order to determine commercial seaweed in west coast of Antalya Province (Lara, Phaselis, Beymelek, Kaş, Kalkan. At the end of study, Rhodophyta (Corallina elongata Ellis & Solander, Corallina officinalis (Linnaeus, Gelidium capillaceum (S.G. Gmelin Kützing, Gelidium latifolium (Greville Bornet & Thuret, Jania adhaerens Lamouroux, Jania rubens (Linnaeus Lamouroux, Porphyra leucosticta Thuret, Heterokontophyta (Cystoseira compressa (Esper Gerloff et Nizamuddin, Cystoseira crinita Duby, Cystoseira elegans Sauvageau, Cystoseira spinosa Sauvageau, Cystoseira stricta (Montagne Sauvageau, Padina pavonica (Linnaeus Thivy, Sargassum vulgare C. Agardh, Chlorophyta (Enteromorpha intestinalis (L. Nees, Gayralia oxysperma (Kützing K.L. Vinogradova ex Scagel et al. ve Ulva lactuca Linnaeus. Species belong to the families have been determined as an important economic potential in this region. Key Words: Mediterranean, Antalya, seaweeds for economic purposing

Characteristics of Phytoplankton Biomass, Primary Production and Community Structure in the Modaomen Channel, Pearl River Estuary, with Special Reference to the Influence of Saltwater Intrusion during Neap and Spring Tides.

Science.gov (United States)

Zhou, Weihua; Gao, Jie; Liao, Jianzu; Shi, Ronggui; Li, Tao; Guo, Yajuan; Long, Aimin

2016-01-01

In recent decades, increasing frequency and intensity of saltwater intrusion in the Modaomen Channel has threatened the freshwater supply in the surrounding cities of the Pearl River Estuary, and ulteriorly changed the environmental conditions of the estuarine waters. Phytoplankton biomass, primary production (PP) and species composition, as well as hydrological and chemical parameters were examined along a downstream transect in the Modaomen Channel during neap tide (NT) and spring tide (ST), when a strong saltwater intrusion event occurred in late September, 2011. A total of 46 species phytoplankton were identified, including Bacillariophyta (25 species), Dinoflagellate (14 species), Chlorophyta (4 species), Cyanophyta (2 species) and Euglenozoa (1 species). The dominant species were shifted from freshwater diatoms (e.g., Melosira granulata and Melosira granulata var. angustissima) in the upper reaches to saline water diatoms (e.g., Skeletonema costatum and Coscinodiscus sp.) in the river mouth. Generally, phytoplankton density, biomass (chl-a) and PP decreased from the upper to lower reaches along the channel, and were significantly higher in NT than those of ST. There was a shift from large-sized phytoplankton (>20 μm) in the upper reaches to relative small-sized cells (5-20 μm) in the lower reaches. Compared to NT, low discharge and flow velocity, coupled with strong easterly winds during ST specially aggravated saltwater intrusion further to the upstream (~50 km from the estuary). The intruded saltwater diluted nutrients, N/P ratios, chl-a, and phytoplankton abundances, and thereby led to a decline in PP during ST.

Time spans and spacers : Molecular phylogenetic explorations in the Cladophora complex (Chlorophyta) from the perspective of rDNA gene and spacer sequences

NARCIS (Netherlands)

Bakker, Frederik Theodoor

1995-01-01

In this study, phylogenetic relationships among genera, species and biogeographic representatives of single Cladophora species within the Cladophorales were analyzed using rDNA gene and spacer sequences. Based on phylogenetic analysis of 18S rRNA gene sequences, the Cladophora complex is shown to be

Enzymatic regulation of photosynthetic and light-independent carbon fixation in Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta and Iridaea cordata (Rhodophyta Regulación enzimática de la fotosíntesis y la fijación de carbono en obscuridad por Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta e Iridaea cordata (Rhodophyta

Directory of Open Access Journals (Sweden)

ALEJANDRO CABELLO-PASINI

2001-06-01

carboxikinasa (PEPCK y fosfoenolpiruvato carboxilasa (PEPC en la Phaeophyta Laminaria setchellii, la Chlorophyta Ulva lactuca y la Rhodophyta Iridaea cordata. Los niveles de clorofila-a no variaron en U. lactuca e I. cordata. Sin embargo, los niveles de pigmentos fueron significativamente menores en la región meristemática de L. setchellii probablemente debido a una falta de diferenciación de los cloroplastos de esta región. De una manera similar, la fotosíntesis neta no varió en el talo de U. lactuca e I. cordata, mientras que se incrementó desde el estipe y el meristemo hacia la lámina de L. setchellii. En contraste con la fotosíntesis, la fijación de carbono en oscuridad fue significantemente mayor en la zona meristemática de L. setchellii sugiriendo un mecanismo para la compensación de la incorporación de carbono en tejido fotosintéticamente limitado. La actividad enzimática de RUBISCO y PEPCK se comportó de una manera similar a los procesos carboxilantes in vivo, indicando que la fotosíntesis y la fijación de carbono en oscuridad son reguladas por la actividad de las enzimas carboxilantes a lo largo del talo de L. setchellii

Biotechnological potential of the seaweed Cladophora rupestris (Chlorophyta, Cladophorales) lipidic extract.

Science.gov (United States)

Stabili, L; Acquaviva, M I; Biandolino, F; Cavallo, R A; De Pascali, S A; Fanizzi, F P; Narracci, M; Cecere, E; Petrocelli, A

2014-09-25

Recently, with the advent of modern technologies, various marine organisms including algae are being studied as sources of natural substances effective on classical microorganisms and able to also combat the new trend of acquired resistance in microbes. In the present study the antimicrobial activity of the lipidic extract of the green seaweed Cladophora rupestris collected in a Mediterranean area, in two sampling periods (January and April), was assayed. The chemical characterization of the lipidic fractions was performed by gas-chromatography and multinuclear and multidimensional NMR spectroscopy. In the lipidic extract of C. rupestris collected in January an antibacterial activity against Enterococcus sp., Streptococcus agalactiae and Vibrio cholerae non-O1 was recorded; by contrast, bacterial inhibition was measured on several Vibrio species only in April. The fatty acid profile of C. rupestris lipidic extract, analyzed by gas chromatography, resulted mainly composed of palmitic, myristic, oleic, α linolenic, palmitoleic and linoleic acids. Moreover, since α-linolenic acid was the predominant ω3 fatty acid in April, we suggest its involvement in the antibacterial activity observed in this month, taking also into account that pure α-linolenic acid resulted effective towards some vibrios strains. C. rupestris fatty acid profile revealed also an interesting composition in polyunsaturated fatty acids in both the considered periods with the ω6/ω3 ratio lower than 1, leading to conclude that this macroalga may be employed as a natural source of ω3. Finally, the (1)H NMR spectrum in CDCl3 of algal lipid fractions showed the characteristic signals of saturated (SAFAs) and unsaturated fatty acids (UFAs) as well as other metabolites and a marked difference in free fatty acids (FFAs) content for the two examined algal lipid fractions. It is noteworthy that C. rupestris lipidic extracts show, by NMR spectroscopy, the signal pattern of polyhydroxybutyrate, a natural

Antibacterial activity of extracts of marine algae from the Red Sea of ...

African Journals Online (AJOL)

Antibacterial activity of extracts of marine algae from the Red Sea of Jeddah, Saudi Arabia. ... African Journal of Biotechnology ... The antibacterial activities of petroleum ether, diethyl ether, ethyl acetate and methanol extracts of marine algae belonging to the Chlorophyta, Phaeophyta and Rhodophyta were studied.

Screening microalgae for some potentially useful agricultural and pharmaceutical secondary metabolites

Czech Academy of Sciences Publication Activity Database

Ordog, V.; Stirk, W. A.; Lenobel, René; Bancířová, Martina; Strnad, Miroslav; van Staden, J.; Szigeti, J.; Nemeth, L.

2004-01-01

Roč. 16, č. 4 (2004), s. 309-314 ISSN 0921-8971 R&D Projects: GA ČR GA522/03/0323 Institutional research plan: CEZ:AV0Z5038910 Keywords : anticancer * antimicrobial * Chlorophyta Subject RIV: EF - Botanics Impact factor: 0.762, year: 2004

Sublittoral seaweed communities on natural and artificial substrata ...

African Journals Online (AJOL)

We also compared algal communities colonising ceramic, marble and pretreated ceramic tiles placed on the reef for six months. We identified 95 algae (14 Chlorophyta, 11 Phaeophyceae, 69 Rhodophyta and one cyanobacterium). Assemblages on natural and artificial substrata were dominated by the brown alga ...

Bacterial Communities Associated with the Lichen Symbiosis▿ †

Science.gov (United States)

Bates, Scott T.; Cropsey, Garrett W. G.; Caporaso, J. Gregory; Knight, Rob; Fierer, Noah

2011-01-01

Lichens are commonly described as a mutualistic symbiosis between fungi and “algae” (Chlorophyta or Cyanobacteria); however, they also have internal bacterial communities. Recent research suggests that lichen-associated microbes are an integral component of lichen thalli and that the classical view of this symbiotic relationship should be expanded to include bacteria. However, we still have a limited understanding of the phylogenetic structure of these communities and their variability across lichen species. To address these knowledge gaps, we used bar-coded pyrosequencing to survey the bacterial communities associated with lichens. Bacterial sequences obtained from four lichen species at multiple locations on rock outcrops suggested that each lichen species harbored a distinct community and that all communities were dominated by Alphaproteobacteria. Across all samples, we recovered numerous bacterial phylotypes that were closely related to sequences isolated from lichens in prior investigations, including those from a lichen-associated Rhizobiales lineage (LAR1; putative N2 fixers). LAR1-related phylotypes were relatively abundant and were found in all four lichen species, and many sequences closely related to other known N2 fixers (e.g., Azospirillum, Bradyrhizobium, and Frankia) were recovered. Our findings confirm the presence of highly structured bacterial communities within lichens and provide additional evidence that these bacteria may serve distinct functional roles within lichen symbioses. PMID:21169444

High levels of intra- and inter-individual polymorphism in the rDNA ITS1 of Caulerpa racemosa (Chlorophyta)

NARCIS (Netherlands)

Fama, P; Olsen, JL; Stam, WT; Procaccini, G

2000-01-01

The coenocytic green alga Caulerpa racemosa colonized the Mediterranean some time after the opening of the Suez Canal in 1869. For most of the past century it has remained confined to the southeastern Mediterranean, but over the past several years the species has been reported in abundance along the

Meiotic genes and sexual reproduction in the green algal class Trebouxiophyceae (Chlorophyta)

KAUST Repository

Fučíková, Karolina

2015-04-06

© 2015 Phycological Society of America. Sexual reproduction is widespread in eukaryotes and is well documented in chlorophytan green algae. In this lineage, however, the Trebouxiophyceae represent a striking exception: in contrast to its relatives Chlorophyceae and Ulvophyceae this group appears to be mostly asexual, as fertilization has been rarely observed. Assessments of sexual reproduction in the Trebouxiophyceae have been based on microscopic observation of gametes fusing. New genomic data offer now the opportunity to check for the presence of meiotic genes, which represent an indirect evidence of a sexual life cycle. Using genomic and transcriptomic data for 12 taxa spanning the phylogenetic breadth of the class, we tried to clarify whether genuine asexuality or cryptic sexuality is the most likely case for the numerous putatively asexual trebouxiophytes. On the basis of these data and a bibliographic review, we conclude that the view of trebouxiophytes as primarily asexual is incorrect. In contrast to the limited number of reports of fertilization, meiotic genes were found in all genomes and transcriptomes examined, even in species presumed asexual. In the taxa examined the totality or majority of the genes were present, Helicosporidium and Auxenochlorella being the only partial exceptions (only four genes present). The evidence of sex provided by the meiotic genes is phylogenetically widespread in the class and indicates that sexual reproduction is not associated with any particular morphological or ecological trait. On the basis of the results, we expect that the existence of the meiotic genes will be documented in all trebouxiophycean genomes that will become available in the future.

Endangered Species

Science.gov (United States)

EPA's Endangered Species Protection Program helps promote recovery of listed species. The ESPP determines if pesticide use in a geographic area may affect any listed species. Find needed limits on pesticide use in Endangered Species Protection Bulletins.

Systematics of Cladophora spp. (Chlorophyta) from North Carolina, USA, based upon morphology and DNA sequence data with a description of Cladophora subtilissima sp. nov.

Science.gov (United States)

Taylor, Robin L; Bailey, Jeffrey Craig; Freshwater, David Wilson

2017-06-01

Identification of Cladophora species is challenging due to conservation of gross morphology, few discrete autapomorphies, and environmental influences on morphology. Twelve species of marine Cladophora were reported from North Carolina waters. Cladophora specimens were collected from inshore and offshore marine waters for DNA sequence and morphological analyses. The nuclear-encoded rRNA internal transcribed spacer regions (ITS) were sequenced for 105 specimens and used in molecular assisted identification. The ITS1 and ITS2 region was highly variable, and sequences were sorted into ITS Sets of Alignable Sequences (SASs). Sequencing of short hyper-variable ITS1 sections from Cladophora type specimens was used to positively identify species represented by SASs when the types were made available. Secondary structures for the ITS1 locus were also predicted for each specimen and compared to predicted structures from Cladophora sequences available in GenBank. Nine ITS SASs were identified and representative specimens chosen for phylogenetic analyses of 18S and 28S rRNA gene sequences to reveal relationships with other Cladophora species. Phylogenetic analyses indicated that marine Cladophorales were polyphyletic and separated into two clades, the Cladophora clade and the "Siphonocladales" clade. Morphological analyses were performed to assess the consistency of character states within species, and complement the DNA sequence analyses. These analyses revealed intra- and interspecific character state variation, and that combined molecular and morphological analyses were required for the identification of species. One new report, Cladophora dotyana, and one new species Cladophora subtilissima sp. nov., were revealed, and increased the biodiversity of North Carolina marine Cladophora to 14 species. © 2017 Phycological Society of America.

Cloning and Characterization of the -Carotene Desaturase Gene from Chlorella protothecoides CS-41

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Meiya Li

2011-01-01

Full Text Available To elucidate the lutein biosynthesis pathway in the lutein-producing alga, Chlorella protothecoides CS-41, the -carotene desaturase gene (zds was isolated from Chlorella protothecoides using the approach of rapid amplification of cDNA ends. The full-length cDNA sequence was 2031 bp and contained 1755 bp putative open reading frame which encodes a 584 amino acid deduced polypeptide whose computed molecular weight was 63.7 kDa. Sequence homology research indicated that the nucleotide and putative protein had sequence identities of 72.5% and 69.5% with those of the green alga Chlamydomonas reinhardtii, respectively. Phylogenetic analysis demonstrated that the ZDS from C. protothecoides CS-41 had a closer relationship with those of chlorophyta and higher plants than with those of other species. In addition, we also found that the zds gene expression was upregulated in response to light.

The nuclear question: rethinking species importance in multi-species animal groups.

Science.gov (United States)

Srinivasan, Umesh; Raza, Rashid Hasnain; Quader, Suhel

2010-09-01

1. Animals group for various benefits, and may form either simple single-species groups, or more complex multi-species associations. Multi-species groups are thought to provide anti-predator and foraging benefits to participant individuals. 2. Despite detailed studies on multi-species animal groups, the importance of species in group initiation and maintenance is still rated qualitatively as 'nuclear' (maintaining groups) or 'attendant' (species following nuclear species) based on species-specific traits. This overly simplifies and limits understanding of inherently complex associations, and is biologically unrealistic, because species roles in multi-species groups are: (i) likely to be context-specific and not simply a fixed species property, and (ii) much more variable than this dichotomy indicates. 3. We propose a new view of species importance (measured as number of inter-species associations), along a continuum from 'most nuclear' to 'least nuclear'. Using mixed-species bird flocks from a tropical rainforest in India as an example, we derive inter-species association measures from randomizations on bird species abundance data (which takes into account species 'availability') and data on 86 mixed-species flocks from two different flock types. Our results show that the number and average strength of inter-species associations covary positively, and we argue that species with many, strong associations are the most nuclear. 4. From our data, group size and foraging method are ecological and behavioural traits of species that best explain nuclearity in mixed-species bird flocks. Parallels have been observed in multi-species fish shoals, in which group size and foraging method, as well as diet, have been shown to correlate with nuclearity. Further, the context in which multi-species groups occur, in conjunction with species-specific traits, influences the role played by a species in a multi-species group, and this highlights the importance of extrinsic factors in

Native species that can replace exotic species in landscaping

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Elisabeth Regina Tempel Stumpf

2015-08-01

Full Text Available Beyond aesthetics, the contemporary landscaping intends to provide other benefits for humans and environment, especially related to the environmental quality of urban spaces and conservation of the species. A trend in this direction is the reduction in the use of exotic plants in their designs, since, over time, they can become agents of replacement of native flora, as it has occurred in Rio Grande do Sul with many species introduced by settlers. However, the use of exotic species is unjustifiable, because the flora diversity of the Bioma Pampa offers many native species with appropriate features to the ornamental use. The commercial cultivation and the implantation of native species in landscaped areas constitute innovations for plant nurseries and landscapers and can provide a positive reduction in extractivism, contributing to dissemination, exploitation and preservation of native flora, and also decrease the impact of chemical products on environment. So, this work intends to identify native species of Bioma Pampa with features and uses similar to the most used exotic species at Brazilian landscaping. The species were selected from consulting books about native plants of Bioma Pampa and plants used at Brazilian landscaping, considering the similarity on habit and architecture, as well as characteristics of leafs, flowers and/or fruits and environmental conditions of occurrence and cultivation. There were identified 34 native species able to properly replace exotic species commonly used. The results show that many native species of Bioma Pampa have interesting ornamental features to landscape gardening, allowing them to replace exotic species that are traditionally cultivated.

ConSpeciFix: Classifying prokaryotic species based on gene flow.

Science.gov (United States)

Bobay, Louis-Marie; Ellis, Brian Shin-Hua; Ochman, Howard

2018-05-16

Classification of prokaryotic species is usually based on sequence similarity thresholds, which are easy to apply but lack a biologically-relevant foundation. Here, we present ConSpeciFix, a program that classifies prokaryotes into species using criteria set forth by the Biological Species Concept, thereby unifying species definition in all domains of life. ConSpeciFix's webserver is freely available at www.conspecifix.com. The local version of the program can be freely downloaded from https://github.com/Bobay-Ochman/ConSpeciFix. ConSpeciFix is written in Python 2.7 and requires the following dependencies: Usearch, MCL, MAFFT and RAxML. ljbobay@uncg.edu.

Diversity and distribution Patterns of the infralittoral green macroalgae from Potiguar basin, Rio Grande do Norte, Northeastern Brazil Diversidade e padrão de distribuição das macroalgas verdes da bacia Potiguar, Rio Grande do Norte, Nordeste do Brasil

Directory of Open Access Journals (Sweden)

Adilma de Lourdes Montenegro Cocentino

2010-12-01

Full Text Available 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 Caulerpa, with 11 species. The results showed that most taxa (89% are rare, and 10% are present at low frequencies. The most frequent species was Caulerpaprolifera (Forssk. J.V. Lamour. occurring at almost all coastal and inner shelf stations, recorded in all campaigns. Species distribution by depth range showed that higher species number occurred on the inner shelf from 10 to 20 m, and a wide vertical distribution pattern was registered for Anadyomenestellata (Wulfen in Jacq. C. Agardh,Chamaedoris peniculum (J. Ellis & Solander Kuntze, Codium isthmocladum Vickers, Microdictyon sp., Udoteaoccidentalis A. Gepp & E. Gepp and Ventricaria ventricosa (J. Agardh J.L. Olsen & J.A. West. Four species, Cladophoracoelothrix Kütz., C.ordinata (Børgensen C. Hoek, Caulerpellaambigua (Okamura Prud'homme & Lokhorst and Halimedasimulans M. Howe, were recorded for the first time in Rio Grande do Norte.Diversidade e padrão de distribuição das algas verdes do infralitoral da Bacia potiguar, RN, nordeste do Brasil foram analisados a partir de material coletado em profundidades que variaram de 2 a 100 m. As coletas foram feitas em dois tipos de dragas durante as quatro campanhas: julho de 2002, maio e novembro de 2003 e maio de 2004, em 43 estações. Chlorophyta está representada por 54 espécies, cinco variedades e três formas. A família mais representativa é Caulerpaceae e dentro da família, o gênero mais diverso é Caulerpa, com 11 espécies. Os resultados

African Journal of Aquatic Science - Vol 34, No 2 (2009)

African Journals Online (AJOL)

... of tissue nitrogen in cultivated Gracilaria gracilis (Rhodophyta) and Ulva lactuca (Chlorophyta) · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. DV Robertson-Andersson, DT Wilson, JJ Bolton, RJ Anderson, GW Maneveldt. http://dx.doi.org/10.2989/AJAS.2009.34.2.7.894 ...

40 CFR 725.3 - Definitions.

Science.gov (United States)

2010-07-01

... microorganism which contains a mobile genetic element which was first identified in a microorganism in a genus...) For commercial distribution, including for test marketing. (ii) For use by the manufacturer, including... the Chlorophyta and the Rhodophyta of the Plantae, and a virus or virus-like particle. Mobile genetic...

Estimating Effects of Species Interactions on Populations of Endangered Species.

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Roth, Tobias; Bühler, Christoph; Amrhein, Valentin

2016-04-01

Global change causes community composition to change considerably through time, with ever-new combinations of interacting species. To study the consequences of newly established species interactions, one available source of data could be observational surveys from biodiversity monitoring. However, approaches using observational data would need to account for niche differences between species and for imperfect detection of individuals. To estimate population sizes of interacting species, we extended N-mixture models that were developed to estimate true population sizes in single species. Simulations revealed that our model is able to disentangle direct effects of dominant on subordinate species from indirect effects of dominant species on detection probability of subordinate species. For illustration, we applied our model to data from a Swiss amphibian monitoring program and showed that sizes of expanding water frog populations were negatively related to population sizes of endangered yellow-bellied toads and common midwife toads and partly of natterjack toads. Unlike other studies that analyzed presence and absence of species, our model suggests that the spread of water frogs in Central Europe is one of the reasons for the decline of endangered toad species. Thus, studying population impacts of dominant species on population sizes of endangered species using data from biodiversity monitoring programs should help to inform conservation policy and to decide whether competing species should be subject to population management.

Confronting species distribution model predictions with species functional traits.

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Wittmann, Marion E; Barnes, Matthew A; Jerde, Christopher L; Jones, Lisa A; Lodge, David M

2016-02-01

Species distribution models are valuable tools in studies of biogeography, ecology, and climate change and have been used to inform conservation and ecosystem management. However, species distribution models typically incorporate only climatic variables and species presence data. Model development or validation rarely considers functional components of species traits or other types of biological data. We implemented a species distribution model (Maxent) to predict global climate habitat suitability for Grass Carp (Ctenopharyngodon idella). We then tested the relationship between the degree of climate habitat suitability predicted by Maxent and the individual growth rates of both wild (N = 17) and stocked (N = 51) Grass Carp populations using correlation analysis. The Grass Carp Maxent model accurately reflected the global occurrence data (AUC = 0.904). Observations of Grass Carp growth rate covered six continents and ranged from 0.19 to 20.1 g day(-1). Species distribution model predictions were correlated (r = 0.5, 95% CI (0.03, 0.79)) with observed growth rates for wild Grass Carp populations but were not correlated (r = -0.26, 95% CI (-0.5, 0.012)) with stocked populations. Further, a review of the literature indicates that the few studies for other species that have previously assessed the relationship between the degree of predicted climate habitat suitability and species functional traits have also discovered significant relationships. Thus, species distribution models may provide inferences beyond just where a species may occur, providing a useful tool to understand the linkage between species distributions and underlying biological mechanisms.

FLORA LICHEN WESTERN MOUNTAINS VRANJE PLACE

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Gordana Bogdanović

2016-07-01

Full Text Available Lichen is a symbiotic plant built by the cells of algae and fungi hyphae. Algae are usually presented - green (Chlorophyta or blue green (Cyanophyta, a mushroom commonly found is ascomycetae and sometimes basidiomycetae. Mushrooms receive oxygen and carbohydrates from algae, and they in turn provide water, CO2 and mineral salts. Lichens are often found on trees and rocks in unpolluted environments and can be used as a bioindicator species. In during 2015-2016. was realized a survey of epiphytic lichen flora of the western mountains in environment of Vranje. Sampling was carried out at 4 locations: Borino brdo, Krstilovica, Markovo Kale and Pljačkovica. Based on the collected and determined samples can be concluded that the study implemented of the area of 25 species of lichens of which: 8 as crust, leafy 12 and 5 shrub. The research results indicate that the lichen flora of the western mountains environments Vranje of a rich and diverse as a result of favorable geographic position, geological and soil composition, climate and plant cover that provide opportunities for the development and survival of lichens.

Physicochemical conditions in affecting the distribution of spring phytoplankton community

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Wei, Yuqiu; Liu, Haijiao; Zhang, Xiaodong; Xue, Bing; Munir, Sonia; Sun, Jun

2017-11-01

To better understand the physicochemical conditions in affecting regional distribution of phytoplankton community, one research cruise was carried out in the Bohai Sea and Yellow Sea during 3rd and 23th May, 2010. The phytoplankton community, including Bacillariophyta (105 taxa), Pyrrophyta (54 taxa), Chrysophyta (1 taxon) and Chlorophyta (2 taxa), had been identified and clearly described from six ecological provinces. And, the six ecological provinces were partitioned based on the top twenty dominant species related with notable physicochemical parameters. In general, the regional distributions of phytoplankton ecological provinces were predominantly influenced by the physicochemical properties induced by the variable water masses and circulations. The predominant diatoms in most of water samples showed well adaptability in turbulent and eutrophic conditions. However, several species of dinoflagellates e.g., Protoperidinium conicum, Protoperidinium triestinum, Protoperidinium sp. and Gymnodinium lohmanni preferred warmer, saltier and nutrient-poor environment. Moreover, the dinoflagellates with high frequency in the Yellow Sea might be transported from the Yellow Sea Warm Current. The horizontal distribution of phytoplankton was depicted by diatoms and controlled by phosphate concentration, while the vertical distribution was mainly supported by light and nutrients availability in the subsurface and bottom layers, respectively.

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

Species delimitation in the Stenocereus griseus (Cactaceae) species complex reveals a new species, S. huastecorum.

Science.gov (United States)

Alvarado-Sizzo, Hernán; Casas, Alejandro; Parra, Fabiola; Arreola-Nava, Hilda Julieta; Terrazas, Teresa; Sánchez, Cristian

2018-01-01

The Stenocereus griseus species complex (SGSC) has long been considered taxonomically challenging because the number of taxa belonging to the complex and their geographical boundaries remain poorly understood. Bayesian clustering and genetic distance-based methods were used based on nine microsatellite loci in 377 individuals of three main putative species of the complex. The resulting genetic clusters were assessed for ecological niche divergence and areolar morphology, particularly spination patterns. We based our species boundaries on concordance between genetic, ecological, and morphological data, and were able to resolve four species, three of them corresponding to S. pruinosus from central Mexico, S. laevigatus from southern Mexico, and S. griseus from northern South America. A fourth species, previously considered to be S. griseus and commonly misidentified as S. pruinosus in northern Mexico showed significant genetic, ecological, and morphological differentiation suggesting that it should be considered a new species, S. huastecorum, which we describe here. We show that population genetic analyses, ecological niche modeling, and morphological studies are complementary approaches for delimiting species in taxonomically challenging plant groups such as the SGSC.

Species delimitation in the Stenocereus griseus (Cactaceae species complex reveals a new species, S. huastecorum.

Directory of Open Access Journals (Sweden)

Hernán Alvarado-Sizzo

Full Text Available The Stenocereus griseus species complex (SGSC has long been considered taxonomically challenging because the number of taxa belonging to the complex and their geographical boundaries remain poorly understood. Bayesian clustering and genetic distance-based methods were used based on nine microsatellite loci in 377 individuals of three main putative species of the complex. The resulting genetic clusters were assessed for ecological niche divergence and areolar morphology, particularly spination patterns. We based our species boundaries on concordance between genetic, ecological, and morphological data, and were able to resolve four species, three of them corresponding to S. pruinosus from central Mexico, S. laevigatus from southern Mexico, and S. griseus from northern South America. A fourth species, previously considered to be S. griseus and commonly misidentified as S. pruinosus in northern Mexico showed significant genetic, ecological, and morphological differentiation suggesting that it should be considered a new species, S. huastecorum, which we describe here. We show that population genetic analyses, ecological niche modeling, and morphological studies are complementary approaches for delimiting species in taxonomically challenging plant groups such as the SGSC.

Save Our Species: Protecting Endangered Species from Pesticides.

Science.gov (United States)

Environmental Protection Agency, Washington, DC.

This full-size poster profiles 11 wildlife species that are endangered. Color illustrations of animals and plants are accompanied by narrative describing their habitats and reasons for endangerment. The reverse side of the poster contains information on the Endangered Species Act, why protecting endangered and threatened species is important, how…

Ulva and Enteromorpha (Ulvaceae, Chlorophyta) from two sides of the Yellow Sea: analysis of nuclear rDNA ITS and plastid rbcL sequence data

Science.gov (United States)

Wang, Jinfeng; Li, Nan; Jiang, Peng; Boo, Sung Min; Lee, Wook Jae; Cui, Yulin; Lin, Hanzhi; Zhao, Jin; Liu, Zhengyi; Qin, Song

2010-07-01

Ulvacean green seaweeds are common worldwide; they formed massive green tides in the Yellow Sea in recent years, which caused marine ecological problems as well as a social issue. We investigated two major genera of the Ulvaceae, Ulva and Enteromorpha, and collected the plastid rbcL and nuclear ITS sequences of specimens of the genera in two sides of the Yellow Sea and analyzed them. Phylogenetic trees of rbcL data show the occurrence of five species of Enteromorpha ( E. compressa, E. flexuosa, E. intestinalis, E. linza and E. prolifera) and three species of Ulva ( U. pertusa, U. rigida and U. ohnoi). However, we found U. ohnoi, which is known as a subtropical to tropical species, at two sites on Jeju Island, Korea. Four ribotypes in partial sequences of 5.8S rDNA and ITS2 from E. compressa were also found. Ribotype network analysis revealed that the common ribotype, occurring in China, Korea and Europe, is connected with ribotypes from Europe and China/Japan. Although samples of the same species were collected from both sides of the Yellow Sea, intraspecific genetic polymorphism of each species was low among samples collected worldwide.

Journal of Biosciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

The prasinophytes (early diverging Chlorophyta), consisting of simple unicellular green algae, occupy a critical position at the base of the green algal tree of life, with some of its representatives viewed as the cell form most similar to the first green alga, the `ancestral green flagellate'. Relatively large-celled unicellular ...

Browse Title Index

African Journals Online (AJOL)

Items 8801 - 8850 of 11090 ... A Mansseri-Lamrioui, A Louerguioui, J Bonaly, ... Vol 13, No 53 (2014), Promoting increased Chlorella sorokiniana Shih. et Krauss (Chlorophyta) biomass ... Vol 16, No 3 (2017), Protection of Lactobacillus acidophilus under in vitro ... Araújo Campos, Pedro Martins Ribeiro Júnior, Fabrício Rabelo ...

Species choice, provenance and species trials among native Brazilian species

Energy Technology Data Exchange (ETDEWEB)

Drumond, M A

1982-01-01

Six papers from the conference are presented. Drumond, M.A., Potential of species native to the semi-arid tropics, 766-781, (Refs. 18), reports on Anadenanthera macrocarpa, Mimosa species, Schinopsis brasiliensis, Spondias tuberosa, Ziziphus joazeiro, Cnidoscolus phyllacanthus, Bursera leptophleos (leptophloeos), Tabebuia impetiginosa, Astronium urundeuva, and Mimosa caesalpinia. Monteiro, R.F.R., Speltz, R.M., Gurgel, J.T. do A.; Silvicultural performance of 24 provenances of Araucaria angustifolia in Parana, 814-824, (Refs. 8). Pires, C.L. da S., Kalil Filho, A.N., Rosa, P.R.F. da, Parente, P.R., Zanatto, A.C.S.; Provenance trials of Cordia alliodora in the State of Sao Paulo, 988-995, (Refs. 9). Nogueira, J.C.B., Siqueira, A.C.M.F., Garrido, M.A.O., Gurgel Garrido, L.M. do A., Rosa, P.R.F., Moraes, J.L. de, Zandarin, M.A., Gurgel Filho, O.A., Trials of some native species in various regions of the State of Sao Paulo, 1051-1063, (Refs. 9) describes Centrolobium tomentosum, Peltophorum dubium, Tabebuia vellosoi, Cariniana legalis, and Balfourodendron riedelianum. Batista, M.P., Borges, J.F., Franco, M.A.B.; Early growth of a native species in comparison with exotics in northeastern Para, Brazil, 1105-1110, (Refs. 3). Jacaranda copaia is compared with Gmelina arborea, Pinus caribaea various hondurensis, Eucalyptus deglupta, and E. urophylla. Lima, P.C.F., Souza, S.M. de, Drumond, M.A.; Trials of native forest species at Petrolina, Pernambuco, 1139-1148, (Refs. 8), deals with Anadenanthera macrocarpa, Piptadenia obliqua, Pithecellobium foliolosum, Astronium urundeuva, Schinopsis brasiliensis, Cassia excelsa, Caesalpinia pyramidalis, Parkia platycephala, Pseudobombax simplicifolium, Tabebuia impetiginosa, Caesalpinia ferrea, and Aspidosperma pyrifolium. 18 references.

Terrestrial animals as invasive species and as species at risk from invasions

Science.gov (United States)

Deborah M. Finch; Dean Pearson; Joseph Wunderle; Wayne Arendt

2010-01-01

Including terrestrial animal species in the invasive species strategy plan is an important step in invasive species management. Invasions by nonindigenous species threaten nearly 50 percent of imperiled native species in the United States and are the Nation's second leading cause of species endangerment. Invasion and conversion of native habitats by exotic species...

Rare species contribute disproportionately to the functional structure of species assemblages.

Science.gov (United States)

Leitão, Rafael P; Zuanon, Jansen; Villéger, Sébastien; Williams, Stephen E; Baraloto, Christopher; Fortunel, Claire; Mendonça, Fernando P; Mouillot, David

2016-04-13

There is broad consensus that the diversity of functional traits within species assemblages drives several ecological processes. It is also widely recognized that rare species are the first to become extinct following human-induced disturbances. Surprisingly, however, the functional importance of rare species is still poorly understood, particularly in tropical species-rich assemblages where the majority of species are rare, and the rate of species extinction can be high. Here, we investigated the consequences of local and regional extinctions on the functional structure of species assemblages. We used three extensive datasets (stream fish from the Brazilian Amazon, rainforest trees from French Guiana, and birds from the Australian Wet Tropics) and built an integrative measure of species rarity versus commonness, combining local abundance, geographical range, and habitat breadth. Using different scenarios of species loss, we found a disproportionate impact of rare species extinction for the three groups, with significant reductions in levels of functional richness, specialization, and originality of assemblages, which may severely undermine the integrity of ecological processes. The whole breadth of functional abilities within species assemblages, which is disproportionately supported by rare species, is certainly critical in maintaining ecosystems particularly under the ongoing rapid environmental transitions. © 2016 The Author(s).

Cylindrospermopsin induced changes in growth, toxin production and antioxidant response of Acutodesmus acuminatus and Microcystis aeruginosa under differing light and nitrogen conditions.

Science.gov (United States)

Chia, Mathias Ahii; Cordeiro-Araújo, Micheline Kézia; Lorenzi, Adriana Sturion; Bittencourt-Oliveira, Maria do Carmo

2017-08-01

Growing evidence suggests that some bioactive metabolites (e.g. cyanotoxins) produced by cyanobacteria have allelopathic potential, due to their inhibitory or stimulatory effects on competing species. Although a number of studies have shown that the cyanotoxin cylindrospermopsin (CYN) has variable effects on phytoplankton species, the impact of changing physicochemical conditions on its allelopathic potential is yet to be investigated. We investigated the physiological response of Microcystis aeruginosa (Cyanobacteria) and Acutodesmus acuminatus (Chlorophyta) to CYN under varying nitrogen and light conditions. At 24h, higher microcystins content of M. aeruginosa was recorded under limited light in the presence of CYN, while at 120h the lower levels of the toxins were observed in the presence of CYN under optimum light. Total MCs concentration was significantly (pnitrogen conditions. On the other hand, there were no significant (p>0.05) changes in total MCs concentrations after exposure to CYN under high nitrogen conditions. As expected, limited light and limited nitrogen conditions resulted in lower cell density of both species, while CYN only significantly (pnitrogen condition, the presence of CYN increased internal H 2 O 2 content of both species, which resulted in significant (pnitrogen. These results showed that M. aeruginosa and A. acuminatus have variable response to CYN under changing light and nitrogen conditions, and demonstrate that need to consider changes in physicochemical conditions during ecotoxicological and ecophysiological investigations. Copyright © 2017 Elsevier Inc. All rights reserved.

Structure and dynamics of phytoplankton in an Amazon lake, Brazil

Directory of Open Access Journals (Sweden)

Ise de Goreth Silva

2010-12-01

Full Text Available Natural lake systems represent important reservoirs for residential water supply, fish production, recreational activities and enjoyment of their natural beauty. Nevertheless, human impacts may affect their health status resulting in degradation and loss of biodiversity. The aim of the present study was to obtain data on the health status of a natural lake located in an indigenous reservation in the Brazilian Amazon, using the phytoplankton community changes along the rainy (June and dry (November seasons of 2006. We collected water (temperature, pH, Secchi depth and conductivity and phytoplankton samples from the subsurface, middle of the water column, and approximately 30cm above the bottom, over 24-hour sampling periods, from a central station in the lake. Samples taken from biotic and abiotic variables were correlated using canonical correspondence analysis (CCA. Results showed that the lake exhibited high temperatures in both seasons, and showed thermal stratification only during the rainy season. Dissolved oxygen exhibited a clinograde pattern in the rainy season and high oxygen in the hypolimnion in the dry season. In the rainy season, the water near the bottom was acidic, turbid and had a greater concentration of phosphorus. Dissolved oxygen, conductivity, pH, nitrite, total phosphorus and total dissolved phosphorus exhibited diel variations in the rainy season, whereas water temperature, dissolved oxygen, total nitrogen and total dissolved phosphorus exhibited significant differences between hours of the day in the dry season. The phytoplankton was represented by 39 taxa, and Chlorophyta showed the greatest species richness, totaling 25 taxa. Among Chlorophyta, desmids were the most diverse, accounting 52%. Bacillariophyta (nine species was the second most diverse group. Cyanophyta was represented by three species, including Merismopedia tenuissima, the most abundant taxon. Despite the occurrence of taxa that indicate organic pollution

Core-satellite species hypothesis and native versus exotic species in secondary succession

Science.gov (United States)

Martinez, Kelsey A.; Gibson, David J.; Middleton, Beth A.

2015-01-01

A number of hypotheses exist to explain species’ distributions in a landscape, but these hypotheses are not frequently utilized to explain the differences in native and exotic species distributions. The core-satellite species (CSS) hypothesis predicts species occupancy will be bimodally distributed, i.e., many species will be common and many species will be rare, but does not explicitly consider exotic species distributions. The parallel dynamics (PD) hypothesis predicts that regional occurrence patterns of exotic species will be similar to native species. Together, the CSS and PD hypotheses may increase our understanding of exotic species’ distribution relative to natives. We selected an old field undergoing secondary succession to study the CSS and PD hypotheses in conjunction with each other. The ratio of exotic to native species (richness and abundance) was observed through 17 years of secondary succession. We predicted species would be bimodally distributed and that exotic:native species ratios would remain steady or decrease through time under frequent disturbance. In contrast to the CSS and PD hypotheses, native species occupancies were not bimodally distributed at the site, but exotic species were. The exotic:native species ratios for both richness (E:Nrichness) and abundance (E:Ncover) generally decreased or remained constant throughout supporting the PD hypothesis. Our results suggest exotic species exhibit metapopulation structure in old field landscapes, but that metapopulation structures of native species are disrupted, perhaps because these species are dispersal limited in the fragmented landscape.

Benthic algal vegetation in Isfjorden, Svalbard

Directory of Open Access Journals (Sweden)

Stein Fredriksen

2015-08-01

Full Text Available Benthic algal vegetation was investigated at 10 sites in Isfjorden, Svalbard. Five sites were visited during summer 2010 and five during summer 2012. Both the littoral and sublittoral vegetation were sampled, the littoral by hand-picking and use of a throwable rake and the sublittoral using a triangular dredge. A total of 88 different taxa were registered, comprising 17 Chlorophyta, 40 Ochrophyta, 30 Rhodophyta and the Xantophyceae Vaucheria sp. The green algae Ulvaria splendens (Ruprecht Vinogradova was recorded in Svalbard for the first time. Most of the sites consisted of hard bottom substrate, but one site, Kapp Wijk, consisted of loose-lying calcareous red algae (rhodoliths and had species not recorded elsewhere. The sublittoral at the other sites was dominated by kelp. Molecular analysis confirmed the presence of the red alga Ceramium virgatum and a dwarf form of the brown alga Fucus vesiculosus. This study provides a baseline for future studies investigating changes in the vegetation due to environmental changes.

Changes of the phytoplankton community as symptoms of deterioration of water quality in a shallow lake.

Science.gov (United States)

Dembowska, Ewa Anna; Mieszczankin, Tomasz; Napiórkowski, Paweł

2018-01-25

Covering more than 60% of the lake surface, macrophytes determined the taxonomic composition of phytoplankton. We have found numerous indications of ecological deterioration and an increased trophic level year to year: an increased total number of taxa; a significantly increased number of species of Chlorophyta, Bacillariophyceae and Cyanoprokaryota; a decreased number of Chrysophyceae; increased Nygaard index, and high diversity and variability of phytoplankton functional groups. Within 2 years (2002 and 2003) algal biomass doubled: from 3.616 to 7.968 mg l -1 . An increased contribution of Chlorococcales and Cyanoprokaryota indicates progressive eutrophication of the lake. The average size of planktonic algae increased, particularly Cyanoprokaryota, where small-celled decreased dramatically and were replaced by large colonies. Cyanoprokaryota remained the dominant group of phytoplankton after 10 years, and the ecosystem of the lake remained in the turbid state. This group of algae had the average biomass 9.734 mg l -1 , which constituted almost 92% of the total biomass.

Comparative effects of herbicides on photosynthesis and growth of tropical estuarine microalgae

Energy Technology Data Exchange (ETDEWEB)

Magnusson, Marie [AIMS at JCU, Australian Institute of Marine Science, School of Marine and Tropical Biology, James Cook University, Townsville, QLD 4811 (Australia); School of Marine and Tropical Biology, James Cook University, Douglas Campus, Townsville 4811 (Australia); Heimann, Kirsten [School of Marine and Tropical Biology, James Cook University, Douglas Campus, Townsville 4811 (Australia)], E-mail: Kirsten.Heimann@jcu.edu.au; Negri, Andrew P. [Australian Institute of Marine Science, PMB 3 Townsville MC, QLD 4810 (Australia)

2008-09-15

Pulse amplitude modulation (PAM) fluorometry is ideally suited to measure the sub-lethal impacts of photosystem II (PSII)-inhibiting herbicides on microalgae, but key relationships between effective quantum yield [Y(II)] and the traditional endpoints growth rate ({mu}) and biomass increase are unknown. The effects of three PSII-inhibiting herbicides; diuron, hexazinone and atrazine, were examined on two tropical benthic microalgae; Navicula sp. (Heterokontophyta) and Nephroselmis pyriformis (Chlorophyta). The relationships between Y(II), {mu} and biomass increase were consistent (r{sup 2} {>=} 0.90) and linear (1:1), validating the utility of PAM fluorometry as a rapid and reliable technique to measure sub-lethal toxicity thresholds of PSII-inhibiting herbicides in these microalgae. The order of toxicity (EC{sub 50} range) was: diuron (16-33 nM) > hexazinone (25-110 nM) > atrazine (130-620 nm) for both algal species. Growth rate and photosynthesis were affected at diuron concentrations that have been detected in coastal areas of the Great Barrier Reef.

Comparative effects of herbicides on photosynthesis and growth of tropical estuarine microalgae

International Nuclear Information System (INIS)

Magnusson, Marie; Heimann, Kirsten; Negri, Andrew P.

2008-01-01

Pulse amplitude modulation (PAM) fluorometry is ideally suited to measure the sub-lethal impacts of photosystem II (PSII)-inhibiting herbicides on microalgae, but key relationships between effective quantum yield [Y(II)] and the traditional endpoints growth rate (μ) and biomass increase are unknown. The effects of three PSII-inhibiting herbicides; diuron, hexazinone and atrazine, were examined on two tropical benthic microalgae; Navicula sp. (Heterokontophyta) and Nephroselmis pyriformis (Chlorophyta). The relationships between Y(II), μ and biomass increase were consistent (r 2 ≥ 0.90) and linear (1:1), validating the utility of PAM fluorometry as a rapid and reliable technique to measure sub-lethal toxicity thresholds of PSII-inhibiting herbicides in these microalgae. The order of toxicity (EC 50 range) was: diuron (16-33 nM) > hexazinone (25-110 nM) > atrazine (130-620 nm) for both algal species. Growth rate and photosynthesis were affected at diuron concentrations that have been detected in coastal areas of the Great Barrier Reef

Two-species occupancy modeling accounting for species misidentification and nondetection

Science.gov (United States)

Chambert, Thierry; Grant, Evan H. Campbell; Miller, David A. W.; Nichols, James; Mulder, Kevin P.; Brand, Adrianne B,

2018-01-01

1. In occupancy studies, species misidentification can lead to false positive detections, which can cause severe estimator biases. Currently, all models that account for false positive errors only consider omnibus sources of false detections and are limited to single species occupancy. 2. However, false detections for a given species often occur because of the misidentification with another, closely-related species. To exploit this explicit source of false positive detection error, we develop a two-species occupancy model that accounts for misidentifications between two species of interest. As with other false positive models, identifiability is greatly improved by the availability of unambiguous detections at a subset of site-occasions. Here, we consider the case where some of the field observations can be confirmed using laboratory or other independent identification methods (“confirmatory data”). 3. We performed three simulation studies to (1) assess the model’s performance under various realistic scenarios, (2) investigate the influence of the proportion of confirmatory data on estimator accuracy, and (3) compare the performance of this two-species model with that of the single-species false positive model. The model shows good performance under all scenarios, even when only small proportions of detections are confirmed (e.g., 5%). It also clearly outperforms the single-species model.

Incorporating Context Dependency of Species Interactions in Species Distribution Models.

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Lany, Nina K; Zarnetske, Phoebe L; Gouhier, Tarik C; Menge, Bruce A

2017-07-01

Species distribution models typically use correlative approaches that characterize the species-environment relationship using occurrence or abundance data for a single species. However, species distributions are determined by both abiotic conditions and biotic interactions with other species in the community. Therefore, climate change is expected to impact species through direct effects on their physiology and indirect effects propagated through their resources, predators, competitors, or mutualists. Furthermore, the sign and strength of species interactions can change according to abiotic conditions, resulting in context-dependent species interactions that may change across space or with climate change. Here, we incorporated the context dependency of species interactions into a dynamic species distribution model. We developed a multi-species model that uses a time-series of observational survey data to evaluate how abiotic conditions and species interactions affect the dynamics of three rocky intertidal species. The model further distinguishes between the direct effects of abiotic conditions on abundance and the indirect effects propagated through interactions with other species. We apply the model to keystone predation by the sea star Pisaster ochraceus on the mussel Mytilus californianus and the barnacle Balanus glandula in the rocky intertidal zone of the Pacific coast, USA. Our method indicated that biotic interactions between P. ochraceus and B. glandula affected B. glandula dynamics across >1000 km of coastline. Consistent with patterns from keystone predation, the growth rate of B. glandula varied according to the abundance of P. ochraceus in the previous year. The data and the model did not indicate that the strength of keystone predation by P. ochraceus varied with a mean annual upwelling index. Balanus glandula cover increased following years with high phytoplankton abundance measured as mean annual chlorophyll-a. M. californianus exhibited the same

Biodiversity patterns of macrophyte and macroinvertebrate communities in two lagoons of Western Greece.

Science.gov (United States)

Fyttis, G.; Reizopoulou, S.; Papastergiadou, E.

2012-04-01

Aquatic macrophytes and benthic macroinvertebrates were studied seasonally (Spring, Autumn, Summer) between the years 2009 - 2011 in two coastal lagoons (Kotychi and Prokopos) located in Peloponnese, Greece, in order to investigate spatial and temporal biodiversity trends related to hydrological processes (degree of confinement, nitrates, phosphates, chl-a, total suspended materials, light irradiance, pH, salinity, temperature and dissolved oxygen). Kotychi lagoon presents a better communication with the sea, while Prokopos has a high degree of confinement. Both ecosystems seasonally receive freshwater input from streams. The submerged aquatic macrophytes constituted a major component of the ecosystems studied. In total, 22 taxa of aquatic macrophytes (angiosperms and macroalgae), 16 taxa for Kotychi (2 Rhodophyta, 8 Chlorophyta, 5 Magnoliophyta, 1 Streptophyta) and 14 taxa for Prokopos (1 Rhodophyta, 5 Chlorophyta, 5 Magnoliophyta, 3 Streptophyta) were found. Ruppia cirrhosa, and Potamogeton pectinatus were dominant in both lagoons. Kotychi lagoon was also dominated by Zostera noltii and Prokopos by Zannichellia pallustris ssp. pedicellata, while the biomass of aquatic species peaked during the summer periods, in both lagoons. The total number of macroinvertebrates found in the lagoons was 28 taxa for Kotychi and 19 for Prokopos. Chironomidae were dominant in both lagoons, while Kotychi was also dominated by Lekanesphaera monodi and Monocorophium insidiosum, and Prokopos by Ostracoda and Lekanesphaera monodi. Benthic diversity ranged from 1.33 to 2.57 in Kotychi and from 0.67 to 2.48 in Prokopos. Species richness, diversity, and abundance of benthic macroinvertebrates were strongly related to aquatic vegetation and to the degree of communication with the marine environment. Moreover, species richness and abundance of both macrophytes and macroinvertebrates were mainly dependent on depth, temperature, pH and concentration of total suspended materials (TSM). Results

Structure and composition of the phytoplanktonic community in TRanca Grande Lagoo (Junín, Perú

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Mauro Mariano-Astocóndor

2014-06-01

Full Text Available The Tranca Grande lagoon is one of the systems where the truchiculture is realized, a productive activity which supports the lake since 1995. It is located in the Paramo floor or Tropical Montano in the Department of Junin, Province of Jauja to 4320 m of altitude (11º43’57?S and (75º13’18? W. The structure and composition of the superficial phytoplanktonic community was studied from monthly samples collected from January to December on 1996 in relation to 21 physical-chemical variables of water. The community showed 51 species belonging to Bacillariophyta, Chlorophyta, Cyanophyta, Euglenophyta, Chrysophyta and Pyrrophyta. The highest average values of density were from Gloeocystis gigas and Ulothrix sp. On the rainy months, the rain fall had a considerable influence on the dilution and sedimentation of the macronutrients responsible for the conductivity, alkalinity, hardness, calcium and magnesium which decrease their values, and likewise the values of the diversity and density decrease. In the period of low-water mark, the characteristics mentioned about rainy period appear on the inverse way. The quantity of species and their density on the phytoplankton were found with the Multiple Regression Analysis. a Species = 7,32+10,59 (The clearness of water - 0,1614 (hardness of calcium + 4,90 (nitrates. b Density = -1,00 + 4397,18 (pH - 223,6 (total alkalinity - 1,4 (phosphates

Agroforestry Species Switchboard

DEFF Research Database (Denmark)

Kindt, R.; John, I.; Ordonez, J.

2016-01-01

The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

Phytoplankton diversity and its relationships to the physico-chemical environment in the Banglang Reservoir, Yala Province

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Saowapa Angsupanich

2004-09-01

Full Text Available The diversity of phytoplankton and its relationships to the physico- chemical environment were studied in Banglang Reservoir, located on the Pattani River in Southern Thailand. Samples were collected monthly from May 2000 to April 2001 at three stations and three different depths: water surface, 10, and 30 meters. Physico-chemical parameters: temperature, pH, dissolved oxygen, alkalinity, conductivity, water transparency, and nutrients were measured simultaneously. One-hundred and thirty-five species in seven divisions of phytoplankton were found. The greatest number of species were in Division Chlorophyta (50%, followed by Cyanophyta (21%, Bacillariophyta (13%, Pyrrophyta (6%, Cryptophyta (4%, Chrysophyta (3% and Euglenophyta (3%. The most diverse genus was Staurastrum (15 species. Phytoplankton density ranged from zero to 2.1x109 cells.m-3. Microcystis aeruginosa Kutzing in January at 30 m at the lacustrine zone had the highest phytoplankton density. By applying a PCA(principal components analysis using the MVSP statistical analysis program on the abundance of species, it was found that Cyclotella meneghiniana Kutzing and Melosira varians Agardh were the most abundant in each station. Diversity index (Simpson’s diversity index was maximum at 10 m at the transition zone and lowest at the outflow zone. The factors affecting the phytoplankton species by Canonical correspondence analysis ordination (PC-ORD programwere alkalinity, water temperature, water transparency, nutrients and conductivity. When the water quality parameters were classified by the trophic level, Banglang Reservoir belonged to oligo-mesotrophic status. Furthermore, Cyclotella meneghiniana Kutzing and Melosira varians Agardh could be used as the phytoplankton indicator of oligo-mesotrophic reservoir.

Distinctive Architecture of the Chloroplast Genome in the Chlorodendrophycean Green Algae Scherffelia dubia and Tetraselmis sp. CCMP 881.

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Turmel, Monique; de Cambiaire, Jean-Charles; Otis, Christian; Lemieux, Claude

2016-01-01

The Chlorodendrophyceae is a small class of green algae belonging to the core Chlorophyta, an assemblage that also comprises the Pedinophyceae, Trebouxiophyceae, Ulvophyceae and Chlorophyceae. Here we describe for the first time the chloroplast genomes of chlorodendrophycean algae (Scherffelia dubia, 137,161 bp; Tetraselmis sp. CCMP 881, 100,264 bp). Characterized by a very small single-copy (SSC) region devoid of any gene and an unusually large inverted repeat (IR), the quadripartite structures of the Scherffelia and Tetraselmis genomes are unique among all core chlorophytes examined thus far. The lack of genes in the SSC region is offset by the rich and atypical gene complement of the IR, which includes genes from the SSC and large single-copy regions of prasinophyte and streptophyte chloroplast genomes having retained an ancestral quadripartite structure. Remarkably, seven of the atypical IR-encoded genes have also been observed in the IRs of pedinophycean and trebouxiophycean chloroplast genomes, suggesting that they were already present in the IR of the common ancestor of all core chlorophytes. Considering that the relationships among the main lineages of the core Chlorophyta are still unresolved, we evaluated the impact of including the Chlorodendrophyceae in chloroplast phylogenomic analyses. The trees we inferred using data sets of 79 and 108 genes from 71 chlorophytes indicate that the Chlorodendrophyceae is a deep-diverging lineage of the core Chlorophyta, although the placement of this class relative to the Pedinophyceae remains ambiguous. Interestingly, some of our phylogenomic trees together with our comparative analysis of gene order data support the monophyly of the Trebouxiophyceae, thus offering further evidence that the previously observed affiliation between the Chlorellales and Pedinophyceae is the result of systematic errors in phylogenetic reconstruction.

Ring species as demonstrations of the continuum of species formation

DEFF Research Database (Denmark)

Pereira, Ricardo José Do Nascimento; Wake, David B.

2015-01-01

In the mid-20th century, Ernst Mayr (1942) and Theodosius Dobzhansky (1958) championed the significance of 'circular overlaps' or 'ring species' as the perfect demonstration of the gradual nature of species formation. As an ancestral species expands its range, wrapping around a geographic barrier......? What conditions favour their formation? Modelling studies have attempted to address these knowledge gaps by estimating the biological parameters that result in stable ring species (Martins et al. 2013), and determining the necessary topographic parameters of the barriers encircled (Monahan et al. 2012......). However, any generalization is undermined by a major limitation: only a handful of ring species are known to exist in nature. In addition, many of them have been broken into multiple species presumed to be evolving independently, usually obscuring the evolutionary dynamics that generate diversity. A paper...

Indicator species of essential forest tree species in the Burdur district.

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Negiz, Mehmet Güvenç; Eser, Yunus; Kuzugüdenll, Emre; Izkan, Kürşad

2015-01-01

The forests of Burdur district for long have been subjected to over grazing and individual selection. As a result of this, majority of the forest areas in the district were degraded. In the district, afforestation efforts included majority of forestry implementations. It is well known that selecting suitable species plays an important role for achieving afforestation efforts. In this context, knowing the indicator species among the target species would be used in afforestation efforts, studies on the interrelationships between environmental factors and target species distribution is vital for selecting suitable species for a given area. In this study, Anatolian Black pine (Pinus nigra), Red pine (Pinus brutia), Crimean juniper (Juniperus excelsa) and Taurus cedar (Cedrus libani), essential tree species, were considered as target species. The data taken from 100 sample plots in Burdur district was used. Interspecific correlation analysis was performed to determine the positive and negative indicator species among each of the target species. As a result of ICA, 2 positive (Berberis crataegina, Juniperus oxycedrus), 2 negative (Phillyrea latifolia, Quercus coccifera) for Crimean Juniper, I positive (Juniperus oxycedrus), 3 negative (Onopordium acanthium, Fraxinus ornus, Phillyrea latifolia) for Anatolian black pine, 3 positive (Paliurus spina-christi, Quercus coccifer, Crataegus orientalis), 2 negative (Berberis crataegina, Astragalus nanus) for Red pine and 3 positive (Berberis crataegina, Rhamnus oleoides, Astragalus prusianus) 2 negative (Paliurus spina-christi, Quercus cerris) for Taurus cedarwere defined as indicator plant species. In this way, practical information was obtained for selecting the most suitable species, among the target species, for afforestation efforts in Burdur district.

Species concept and speciation

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Amal Y. Aldhebiani

2018-03-01

Full Text Available Defining and recognizing a species has been a controversial issue for a long time. To determine the variation and the limitation between species, many concepts have been proposed. When a taxonomist study a particular taxa, he/she must adopted a species concept and provide a species limitation to define this taxa. In this paper some of species concepts are discussed starting from the typological species concepts to the phylogenetic concept. Positive and negative aspects of these concepts are represented in addition to their application. Keywords: Species concept, Species limitation, Species, Taxonomy, Classification

First and second line mechanisms of cadmium detoxification in the lichen photobiont Trebouxia impressa (Chlorophyta)

International Nuclear Information System (INIS)

Sanita di Toppi, L.; Pawlik-Skowronska, B.; Vurro, E.; Vattuone, Z.; Kalinowska, R.; Restivo, F.M.; Musetti, R.; Skowronski, T.

2008-01-01

'First line' defence mechanisms, such as phytochelatin biosynthesis, and 'second line' mechanisms, such as stress protein induction, were investigated in cadmium-exposed cells of Trebouxia impressa Ahmadjian, a green microalgal species that is a common photobiont of the lichen Physcia adscendens (Fr.) H. Olivier. When T. impressa cells were exposed to 0, 9 and 18 μM Cd for 6, 18 and 48 h, glutathione and phytochelatins efficiently protected the cells against Cd damage. By contrast, the highest Cd concentration (36 μM) at the longest exposure-time (48 h) caused marked drops in glutathione and phytochelatin content, several types of ultrastructural damage, and decreases in cell density and total chlorophyll concentration. In this case, induction of stress proteins was observed, but only long after the induction of phytochelatins. Thus, stress proteins could represent a 'second line' mechanism to counteract Cd stress, activated when there is a decline in the 'first line' mechanism of Cd detoxification given by phytochelatins. - Trebouxia impressa photobionts protect themselves against cadmium stress by means of phytochelatins and stress proteins

First and second line mechanisms of cadmium detoxification in the lichen photobiont Trebouxia impressa (Chlorophyta)

Energy Technology Data Exchange (ETDEWEB)

Sanita di Toppi, L. [Dipartimento di Biologia Evolutiva e Funzionale, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy)], E-mail: luigi.sanitaditoppi@unipr.it; Pawlik-Skowronska, B. [Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland); Vurro, E. [Dipartimento di Biologia Evolutiva e Funzionale, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy); Vattuone, Z. [Dipartimento di Biologia Evolutiva e Funzionale, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy); Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland); Kalinowska, R. [Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland); Restivo, F.M. [Dipartimento di Genetica, Biologia dei Microrganismi, Antropologia, Evoluzione, viale G.P. Usberti 11/A, Universita di Parma, 43100 Parma (Italy); Musetti, R. [Dipartimento di Biologia Applicata alla Difesa delle Piante, via delle Scienze 208, Universita di Udine, 33100 Udine (Italy); Skowronski, T. [Centre for Ecological Research, Polish Academy of Sciences, Experimental Station, Niecala 18/3, 20080 Lublin (Poland)

2008-01-15

'First line' defence mechanisms, such as phytochelatin biosynthesis, and 'second line' mechanisms, such as stress protein induction, were investigated in cadmium-exposed cells of Trebouxia impressa Ahmadjian, a green microalgal species that is a common photobiont of the lichen Physcia adscendens (Fr.) H. Olivier. When T. impressa cells were exposed to 0, 9 and 18 {mu}M Cd for 6, 18 and 48 h, glutathione and phytochelatins efficiently protected the cells against Cd damage. By contrast, the highest Cd concentration (36 {mu}M) at the longest exposure-time (48 h) caused marked drops in glutathione and phytochelatin content, several types of ultrastructural damage, and decreases in cell density and total chlorophyll concentration. In this case, induction of stress proteins was observed, but only long after the induction of phytochelatins. Thus, stress proteins could represent a 'second line' mechanism to counteract Cd stress, activated when there is a decline in the 'first line' mechanism of Cd detoxification given by phytochelatins. - Trebouxia impressa photobionts protect themselves against cadmium stress by means of phytochelatins and stress proteins.

Molecular evidence for a diverse green algal community growing in the hair of sloths and a specific association with Trichophilus welckeri (Chlorophyta, Ulvophyceae

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Chiarello Adriano G

2010-03-01

Full Text Available Abstract Background Sloths are slow-moving arboreal mammals inhabiting tropical rainforests in Central and South America. The six living species of sloths are occasionally reported to display a greenish discoloration of their pelage. Trichophilus welckeri, a green algal species first described more than a century ago, is widely believed to discolor the animals fur and provide the sloth with effective camouflage. However, this phenomenon has not been explored in any detail and there is little evidence to substantiate this widely held opinion. Results Here we investigate the genetic diversity of the eukaryotic community present in fur of all six extant species of sloth. Analysis of 71 sloth hair samples yielding 426 partial 18S rRNA gene sequences demonstrates a diverse eukaryotic microbial assemblage. Phylogenetic analysis reveals that sloth fur hosts a number of green algal species and suggests that acquisition of these organisms from the surrounding rainforest plays an important role in the discoloration of sloth fur. However, an alga corresponding to the morphological description of Trichophilus welckeri was found to be frequent and abundant on sloth fur. Phylogenetic analysis demonstrated the retention of this alga on the fur of sloths independent of geographic location. Conclusions These results demonstrate a unique diverse microbial eukaryotic community in the fur of sloths from Central and South America. Our analysis streghtens the case for symbiosis between sloths and Trichophilus welckeri.

Chemical compositions of the marine algae Gracilaria salicornia (Rhodophyta) and Ulva lactuca (Chlorophyta) as a potential food source.

Science.gov (United States)

Tabarsa, Mehdi; Rezaei, Masoud; Ramezanpour, Zohreh; Waaland, Joseph Robert

2012-09-01

The nutritional compositions of two edible red (Gracilaria salicornia) and green (Ulva lactuca) seaweeds were determined to evaluate their possible uses as potential food ingredients. In general, these species contained limited amounts of lipids ranging between 0.99 and 2.00 g 100 g(-1) dry weight) and considerably high amount of minerals, especially in G. salicornia (38.91 g 100 g(-1) d.w.). The crude protein values varied between 9.58 and 10.69 g 100 g(-1) d.w. Amounts for total amino acids were 889.78 ± 22.64 mg g(-1) protein d.w. in G. salicornia and 543.3 ± 15.14 mg g(-1) protein d.w. in U. lactuca. The most abundant fatty acids were C12:0, C16:0, C20:4 ω6 and C22:5 ω3, in addition to C18:1 in G. salicornia. Both seaweed species were balanced sources of ω3 and ω6 fatty acids with a ratio of ω6/ω3 that varied between 1.2 and 1.17. Between the seaweeds investigated, high levels of K (2414.02-11 380.06 mg 100 g(-1) d.w.) were observed and the amounts of Ca, Na and Fe were higher than those reported for land plants. Thus, G. salicornia and U. lactuca may be utilised as value-added products for human nutrition purposes. Copyright © 2012 Society of Chemical Industry.

Species-area relationships are controlled by species traits.

Science.gov (United States)

Franzén, Markus; Schweiger, Oliver; Betzholtz, Per-Eric

2012-01-01

The species-area relationship (SAR) is one of the most thoroughly investigated empirical relationships in ecology. Two theories have been proposed to explain SARs: classical island biogeography theory and niche theory. Classical island biogeography theory considers the processes of persistence, extinction, and colonization, whereas niche theory focuses on species requirements, such as habitat and resource use. Recent studies have called for the unification of these two theories to better explain the underlying mechanisms that generates SARs. In this context, species traits that can be related to each theory seem promising. Here we analyzed the SARs of butterfly and moth assemblages on islands differing in size and isolation. We tested whether species traits modify the SAR and the response to isolation. In addition to the expected overall effects on the area, traits related to each of the two theories increased the model fit, from 69% up to 90%. Steeper slopes have been shown to have a particularly higher sensitivity to area, which was indicated by species with restricted range (slope = 0.82), narrow dietary niche (slope= 0.59), low abundance (slope= 0.52), and low reproductive potential (slope = 0.51). We concluded that considering species traits by analyzing SARs yields considerable potential for unifying island biogeography theory and niche theory, and that the systematic and predictable effects observed when considering traits can help to guide conservation and management actions.

Differentiation of surface properties of chlorococcalean algae by means of aqueous two phase systems

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Jan Burczyk

2014-01-01

Full Text Available Algal cells belonging to various strains of Chlorococcales (Chlorophyta have been partitioned in aqueous two-phase systems containing ionogenic polymers, DEAE-dextran or SDS-dextran, at various pH values. Strain-specific differences of partition type which have been found in the phase systems used can be useful for distinguishing of algal cells.

Synopsis of the Oxyethira flavicornis species group with new Japanese Oxyethira species (Trichoptera, Hydroptilidae

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Oláh, J.

2013-06-01

Full Text Available A brief synopsis of the Oxyethira flavicornis species group is produced by the examination of type materials. Diagrammatic drawings with similar style were prepared for all the known and for the new species. Short description of genus Oxyethira, subgenus Oxyethira, species group of Oxyethira flavicornis are presented together with the description of five species clusters: O. datra new species cluster, O. ecornuta new species cluster, O. flavicornis new species cluster, O. hiroshima new species cluster, O. tiunovae new species cluster. Five new species are described from the O. flavicornis species group: O chitosea sp. n., O. hena sp. n., O. hiroshima sp. n., O. kakida sp. n., O. mekunna sp. n. One new species is described from the Oxyethira grisea species group: Oxyethira ozea sp. n. and two new species from the Oxyethira ramosa species group: Oxyethira miea sp. n., Oxyethira okinawa sp. n.

Structural characterization and Biological Activity of Sulfolipids from selected Marine Algae

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El Baz, F. K.

2013-12-01

Full Text Available The sulfolipid classes (SLs in the total lipids of five species of marine algae, two species of Rhodophyta (Laurencia popillose, Galaxoura cylindriea, one species of Chlorophyta (Ulva fasciata, and two species of Phaeophyta (Dilophys fasciola, Taonia atomaria were separated and purified on DEAE-cellulose column chromatography. The SLs component was identified by IR, gas chromatography MS/MS and liquid chromatography MS/MS. The level of SLs contents va ried from 1.25% (in L. papillose to 11.82% (in D. fasciola of the total lipid contents. However, no significant differences in sulfate content (0.13 – 0.21% were observed among all these algae species. All SLs were characterized by high contents of palmitic acid (C 16:0, which ranged from 30.91% in G. cylindriea to 63.11% in T. atomatia. The main constitutes of algal sulfolipids were identified as sulfoquinovosyl-di-acylglycerol and sulfoquinovosyl acylglycerol. The sulfolipids of different algal species exhibited remarkable antiviral activity against herps simplex virus type 1 (HSV-1 with an IC50 ranging from 18.75 to 70. 2 μg mL–1. Moreover, algal sulfolipid inhibited the growth of the tumor cells of breast and liver human cancer cells with IC50 values ranging from 0.40 to 0.67 μg mL–1 for human breast adenocarcinoma cells (MCF7.Se separaron diferentes clases sulfolípidos (SL a partir de los lípidos totales de cinco especies de algas marinas: una especie de Chlorophyta (Ulva fasciata, dos especies de Phaeophyta (Dilophys fasciola, Taonia atomaria y dos especies de Rhodophyta (Laurencia popillose, Galaxoura cylindriea que se purificaron mediante cromatografía en columna de DEAE-celulosa. Los components de SLs fueron identificados por IR, cromatografía de gases MS/MS y cromatografía líquida MS/ MS. Los contenidos de SL en relación al total de lípidos varió de 1,25% (en L. papilosa al 11,82% (en D. fasciola. Sin embargo, no hay diferencias significativas en el contenido de sulfato

Relating species abundance distributions to species-area curves in two Mediterranean-type shrublands

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Keeley, Jon E.

2003-01-01

Based on both theoretical and empirical studies there is evidence that different species abundance distributions underlie different species-area relationships. Here I show that Australian and Californian shrubland communities (at the scale from 1 to 1000 m2) exhibit different species-area relationships and different species abundance patterns. The species-area relationship in Australian heathlands best fits an exponential model and species abundance (based on both density and cover) follows a narrow log normal distribution. In contrast, the species-area relationship in Californian shrublands is best fit with the power model and, although species abundance appears to fit a log normal distribution, the distribution is much broader than in Australian heathlands. I hypothesize that the primary driver of these differences is the abundance of small-stature annual species in California and the lack of annuals in Australian heathlands. Species-area is best fit by an exponential model in Australian heathlands because the bulk of the species are common and thus the species-area curves initially rise rapidly between 1 and 100 m2. Annuals in Californian shrublands generate very broad species abundance distributions with many uncommon or rare species. The power function is a better model in these communities because richness increases slowly from 1 to 100 m2 but more rapidly between 100 and 1000 m2due to the abundance of rare or uncommon species that are more likely to be encountered at coarser spatial scales. The implications of this study are that both the exponential and power function models are legitimate representations of species-area relationships in different plant communities. Also, structural differences in community organization, arising from different species abundance distributions, may lead to different species-area curves, and this may be tied to patterns of life form distribution.

Use of species-specific PCR for the identification of 10 sea cucumber species

Science.gov (United States)

Wen, Jing; Zeng, Ling

2014-11-01

We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species. Ten reverse species-specific primers designed from the 16S rRNA gene, in combination with one forward universal primer, generated PCR fragments of ca. 270 bp length for each species. The specificity of the PCR assay was tested with DNA of samples of 21 sea cucumber species. Amplification was observed in specific species only. The species-specific PCR method we developed was successfully applied to authenticate species of commercial products of dehydrated sea cucumber, and was proven to be a useful, rapid, and low-cost technique to identify the origin of the sea cucumber product.

Diversity of cuticular wax among Salix species and Populus species hybrids.

Science.gov (United States)

Cameron, Kimberly D; Teece, Mark A; Bevilacqua, Eddie; Smart, Lawrence B

2002-08-01

The leaf cuticular waxes of three Salix species and two Populus species hybrids, selected for their ability to produce high amounts of biomass, were characterized. Samples were extracted in CH(2)Cl(2) three times over the growing season. Low kV SEM was utilized to observe differences in the ultrastructure of leaf surfaces from each clone. Homologous series of wax components were classified into organic groups, and the variation in wax components due to clone, sample time, and their interaction was identified. All Salix species and Populus species hybrids showed differences in total wax load at each sampling period, whereas the pattern of wax deposition over time differed only between the Salix species. A strong positive relationship was identified between the entire homologous series of alcohols and total wax load in all clones. Similarly strong relationships were observed between fatty acids and total wax load as well as fatty acids and alcohols in two Salix species and one Populus species hybrid. One Salix species, S. dasyclados, also displayed a strong positive relationship between alcohols and alkanes. These data indicate that species grown under the same environmental conditions produce measurably different cuticular waxes and that regulation of wax production appears to be different in each species. The important roles cuticular waxes play in drought tolerance, pest, and pathogen resistance, as well as the ease of wax extraction and analysis, strongly suggest that the characteristics of the cuticular wax may prove to be useful selectable traits in a breeding program.

Scale dependence in species turnover reflects variance in species occupancy.

Science.gov (United States)

McGlinn, Daniel J; Hurlbert, Allen H

2012-02-01

Patterns of species turnover may reflect the processes driving community dynamics across scales. While the majority of studies on species turnover have examined pairwise comparison metrics (e.g., the average Jaccard dissimilarity), it has been proposed that the species-area relationship (SAR) also offers insight into patterns of species turnover because these two patterns may be analytically linked. However, these previous links only apply in a special case where turnover is scale invariant, and we demonstrate across three different plant communities that over 90% of the pairwise turnover values are larger than expected based on scale-invariant predictions from the SAR. Furthermore, the degree of scale dependence in turnover was negatively related to the degree of variance in the occupancy frequency distribution (OFD). These findings suggest that species turnover diverges from scale invariance, and as such pairwise turnover and the slope of the SAR are not redundant. Furthermore, models developed to explain the OFD should be linked with those developed to explain species turnover to achieve a more unified understanding of community structure.

Cryptic species as a window into the paradigm shift of the species concept.

Science.gov (United States)

Fišer, Cene; Robinson, Christopher T; Malard, Florian

2018-02-01

The species concept is the cornerstone of biodiversity science, and any paradigm shift in the delimitation of species affects many research fields. Many biologists now are embracing a new "species" paradigm as separately evolving populations using different delimitation criteria. Individual criteria can emerge during different periods of speciation; some may never evolve. As such, a paradigm shift in the species concept relates to this inherent heterogeneity in the speciation process and species category-which is fundamentally overlooked in biodiversity research. Cryptic species fall within this paradigm shift: they are continuously being reported from diverse animal phyla but are poorly considered in current tests of ecological and evolutionary theory. The aim of this review is to integrate cryptic species in biodiversity science. In the first section, we address that the absence of morphological diversification is an evolutionary phenomenon, a "process" counterpart to the long-studied mechanisms of morphological diversification. In the next section regarding taxonomy, we show that molecular delimitation of cryptic species is heavily biased towards distance-based methods. We also stress the importance of formally naming of cryptic species for better integration into research fields that use species as units of analysis. Finally, we show that incorporating cryptic species leads to novel insights regarding biodiversity patterns and processes, including large-scale biodiversity assessments, geographic variation in species distribution and species coexistence. It is time for incorporating multicriteria species approaches aiming to understand speciation across space and taxa, thus allowing integration into biodiversity conservation while accommodating for species uncertainty. © 2018 John Wiley & Sons Ltd.

Insight into the risk of replenishing urban landscape ponds with reclaimed wastewater.

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Chen, Rong; Ao, Dong; Ji, Jiayuan; Wang, Xiaochang C; Li, Yu-You; Huang, Yue; Xue, Tao; Guo, Hongbing; Wang, Nan; Zhang, Lu

2017-02-15

Increasing use of reclaimed wastewater (RW) for replenishing urban landscape ponds has aroused public concern about the water quality. Three ponds replenished with RW in three cities in China were chosen to investigate 22 indexes of water quality in five categories. This was achieved by comparing three pairs of ponds in the three different cities, where one pond in each pair was replenished with RW and the other with surface water (SW). The nutrients condition, heavy metal concentration and ecotoxicity did not differ significantly between RW- and SW-replenished ponds. By contrast, significant differences were observed in algal growth and pathogen risk. RW ponds presented a Cyanophyta-Chlorophyta-Bacillariophyta type with high algal diversity while SW ponds presented a Cyanophyta type with low diversity. Regrowth of bacterial pathogens and especially survival of viral pathogens in RW, was the main driver behind the higher risk for RW ponds compared with SW ones. The duration of RW replenishment was proved to have a marked impact on the algal growth and pathogen risk. With continued RW replenishment, non-dominant algal species subjected to decrease while dominant species were enhanced resulting in the biomass increasing but diversity declining, and the risk posed by viral pathogens might become greater. Copyright © 2016 Elsevier B.V. All rights reserved.

Biofilm scrubbing for restoration—algae community composition and succession in artificial streams

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Magdalena Mayr

2016-09-01

Full Text Available Photoautotrophic biofilms play a pivotal role in self-purification of rivers. We took advantage of the biofilm’s cleaning capacity by applying artificial stream mesocosms, called algae turf scrubberTM (ATS, to reduce the nutrient load of a highly eutrophicated backwater in Vienna (Austria. Since purification strongly depends on benthic algae on the ATS, we focused on the algae community composition and succession. Estimation of coverage, photographic documentation for micromapping, species identification and pigment analyses were carried out. Already one week after exposition, 20–30 different taxa were recorded, suggesting a rapid colonization of the substrate. In total around 200 taxa were identified, mainly belonging to Chlorophyta, Bacillariophyceae and Cyanoprokaryota. Nonmetric multidimensional scaling implied that season and succession strongly influenced species composition on the ATS and a minimum turnover of 0.28 indicates a development towards a more stable community at the end of experiments. We measured maximum biomass production of ~250 g m−2 in June and August and during a period of 5 months nearly 19 kg ha−1 phosphorus could be removed. ATS systems proved to retain nutrients and produce algae biomass in an environmentally friendly and cost effective way and thus support restoration of highly eutrophicated water bodies.

An Improved DNA Extraction Method for Efficient and Quantitative Recovery of Phytoplankton Diversity in Natural Assemblages.

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Jian Yuan

Full Text Available Marine phytoplankton are highly diverse with different species possessing different cell coverings, posing challenges for thoroughly breaking the cells in DNA extraction yet preserving DNA integrity. While quantitative molecular techniques have been increasingly used in phytoplankton research, an effective and simple method broadly applicable to different lineages and natural assemblages is still lacking. In this study, we developed a bead-beating protocol based on our previous experience and tested it against 9 species of phytoplankton representing different lineages and different cell covering rigidities. We found the bead-beating method enhanced the final yield of DNA (highest as 2 folds in comparison with the non-bead-beating method, while also preserving the DNA integrity. When our method was applied to a field sample collected at a subtropical bay located in Xiamen, China, the resultant ITS clone library revealed a highly diverse assemblage of phytoplankton and other micro-eukaryotes, including Archaea, Amoebozoa, Chlorophyta, Ciliphora, Bacillariophyta, Dinophyta, Fungi, Metazoa, etc. The appearance of thecate dinoflagellates, thin-walled phytoplankton and "naked" unicellular organisms indicates that our method could obtain the intact DNA of organisms with different cell coverings. All the results demonstrate that our method is useful for DNA extraction of phytoplankton and environmental surveys of their diversity and abundance.

A globally-distributed alien invasive species poses risks to United States imperiled species.

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McClure, Meredith L; Burdett, Christopher L; Farnsworth, Matthew L; Sweeney, Steven J; Miller, Ryan S

2018-03-28

In the midst of Earth's sixth mass extinction event, non-native species are a driving factor in many imperiled species' declines. One of the most widespread and destructive alien invasive species in the world, wild pigs (Sus scrofa) threaten native species through predation, habitat destruction, competition, and disease transmission. We show that wild pigs co-occur with up to 87.2% of imperiled species in the contiguous U.S. identified as susceptible to their direct impacts, and we project increases in both the number of species at risk and the geographic extent of risks by 2025. Wild pigs may therefore present a severe threat to U.S. imperiled species, with serious implications for management of at-risk species throughout wild pigs' global distribution. We offer guidance for efficient allocation of research effort and conservation resources across species and regions using a simple approach that can be applied to wild pigs and other alien invasive species globally.

TAXONOMIC DIVERSITY AND THE ROLE OF ALGAEFLORA FOR BIOLOGICAL DEPURATION OF WATERS FROM RIVER COGÂLNIC (R. MOLDOVA

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SALARU VICTOR

2008-11-01

Full Text Available During 2004-2005 there were performed studies regarding the taxonomic structure of the algaeflora in river Cogâlnic in order to point out the role of the algae during the process of water quality improvement and the role of the indicator of the most representative species. River Cogâlnic, or Cunduc, starts from nearby village Iurceni, district Nisporeni and flows into lake Sasac, and runs for a distance of 243 km. Decrease of the analyzed water quality from the river is caused by the sewerage waters from different sectors from town Hinceshti and Cimishlia that are directed into the river without any depuration. We've studied about 118 samples in which we've discovered about 382 species and intraspecific taxonomic units of algae of the following types: Cyanophyta -73, Euglenophyta-75, Chlorophyta-111, Xantophyta-3, Bacillariophyta-118 and Chrysophyta-2. Mass development of the euglena within Colgalnic river, among which are the following types of species Euglena-26, Trachelomonas-14 and Phacus-13, demonstrate a high level of trophicity in water. Among the chloride algae predominate the following species Scenedesmus-21, and from cyanophyta species predominates Oscillatoria-23. The high taxonomic level of the bacillariophyta algae is determined by species as Navicula-27, Nitzschia-24 and Surirella-16. Most of species refer to categories β and β-α , demonstrating a high level of water pollution. This fact speaks about the high concentration of nitrogen and phosphor compounds in water. It was demonstrated that as far as we go from the places were the sewerage waters flow into the river, the excessive quantities of biological elements decrease clearly. Also, go down the quantity of bicarbonates and oxidizers. Numeric growth of the algae is nothing else but a positive role for water depuration.

Silica gel matrix immobilized Chlorophyta hydrodictyon africanum ...

African Journals Online (AJOL)

Aghomotsegin

2015-08-05

Aug 5, 2015 ... The algae-silica gel adsorbent was used for batch sorption studies of a cationic dye, ... traditional methods of treating industrial effluent, these ... Author(s) agree that this article remains permanently open access under the terms of the Creative ... sodium silicate solution (v/v) and 25 mL of distilled water. With.

Assessing species boundaries using multilocus species delimitation in a morphologically conserved group of neotropical freshwater fishes, the Poecilia sphenops species complex (Poeciliidae.

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Justin C Bagley

Full Text Available Accurately delimiting species is fundamentally important for understanding species diversity and distributions and devising effective strategies to conserve biodiversity. However, species delimitation is problematic in many taxa, including 'non-adaptive radiations' containing morphologically cryptic lineages. Fortunately, coalescent-based species delimitation methods hold promise for objectively estimating species limits in such radiations, using multilocus genetic data. Using coalescent-based approaches, we delimit species and infer evolutionary relationships in a morphologically conserved group of Central American freshwater fishes, the Poecilia sphenops species complex. Phylogenetic analyses of multiple genetic markers (sequences of two mitochondrial DNA genes and five nuclear loci from 10/15 species and genetic lineages recognized in the group support the P. sphenops species complex as monophyletic with respect to outgroups, with eight mitochondrial 'major-lineages' diverged by ≥2% pairwise genetic distances. From general mixed Yule-coalescent models, we discovered (conservatively 10 species within our concatenated mitochondrial DNA dataset, 9 of which were strongly supported by subsequent multilocus Bayesian species delimitation and species tree analyses. Results suggested species-level diversity is underestimated or overestimated by at least ~15% in different lineages in the complex. Nonparametric statistics and coalescent simulations indicate genealogical discordance among our gene tree results has mainly derived from interspecific hybridization in the nuclear genome. However, mitochondrial DNA show little evidence for introgression, and our species delimitation results appear robust to effects of this process. Overall, our findings support the utility of combining multiple lines of genetic evidence and broad phylogeographical sampling to discover and validate species using coalescent-based methods. Our study also highlights the

Cladophora (Chlorophyta) spp. Harbor Human Bacterial Pathogens in Nearshore Water of Lake Michigan†

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Ishii, Satoshi; Yan, Tao; Shively, Dawn A.; Byappanahalli, Muruleedhara N.; Whitman, Richard L.; Sadowsky, Michael J.

2006-01-01

Cladophora glomerata, a macrophytic green alga, is commonly found in the Great Lakes, and significant accumulations occur along shorelines during the summer months. Recently, Cladophora has been shown to harbor high densities of the fecal indicator bacteria Escherichia coli and enterococci. Cladophora may also harbor human pathogens; however, until now, no studies to address this question have been performed. In the present study, we determined whether attached Cladophora, obtained from the Lake Michigan and Burns Ditch (Little Calumet River, Indiana) sides of a breakwater during the summers of 2004 and 2005, harbored the bacterial pathogens Shiga toxin-producing Escherichia coli (STEC), Salmonella, Shigella, and Campylobacter. The presence of potential pathogens and numbers of organisms were determined by using cultural methods and by using conventional PCR, most-probable-number PCR (MPN-PCR), and quantitative PCR (QPCR) performed with genus- and toxin-specific primers and probes. While Shigella and STEC were detected in 100% and 25%, respectively, of the algal samples obtained near Burns Ditch in 2004, the same pathogens were not detected in samples collected in 2005. MPN-PCR and QPCR allowed enumeration of Salmonella in 40 to 80% of the ditch- and lakeside samples, respectively, and the densities were up to 1.6 × 103 cells per g Cladophora. Similarly, these PCR methods allowed enumeration of up to 5.4 × 102 Campylobacter cells/g Cladophora in 60 to 100% of lake- and ditchside samples. The Campylobacter densities were significantly higher (P Cladophora samples than in the ditchside Cladophora samples. DNA fingerprint analyses indicated that genotypically identical Salmonella isolates were associated with geographically and temporally distinct Cladophora samples. However, Campylobacter isolates were genetically diverse. Since animal hosts are thought to be the primary habitat for Campylobacter and Salmonella species, our results suggest that Cladophora is a

Cladophora (Chlorophyta) spp. harbor human bacterial pathogens in nearshore water of Lake Michigan.

Science.gov (United States)

Ishii, Satoshi; Yan, Tao; Shively, Dawn A; Byappanahalli, Muruleedhara N; Whitman, Richard L; Sadowsky, Michael J

2006-07-01

Cladophora glomerata, a macrophytic green alga, is commonly found in the Great Lakes, and significant accumulations occur along shorelines during the summer months. Recently, Cladophora has been shown to harbor high densities of the fecal indicator bacteria Escherichia coli and enterococci. Cladophora may also harbor human pathogens; however, until now, no studies to address this question have been performed. In the present study, we determined whether attached Cladophora, obtained from the Lake Michigan and Burns Ditch (Little Calumet River, Indiana) sides of a breakwater during the summers of 2004 and 2005, harbored the bacterial pathogens Shiga toxin-producing Escherichia coli (STEC), Salmonella, Shigella, and Campylobacter. The presence of potential pathogens and numbers of organisms were determined by using cultural methods and by using conventional PCR, most-probable-number PCR (MPN-PCR), and quantitative PCR (QPCR) performed with genus- and toxin-specific primers and probes. While Shigella and STEC were detected in 100% and 25%, respectively, of the algal samples obtained near Burns Ditch in 2004, the same pathogens were not detected in samples collected in 2005. MPN-PCR and QPCR allowed enumeration of Salmonella in 40 to 80% of the ditch- and lakeside samples, respectively, and the densities were up to 1.6 x 10(3) cells per g Cladophora. Similarly, these PCR methods allowed enumeration of up to 5.4 x 10(2) Campylobacter cells/g Cladophora in 60 to 100% of lake- and ditchside samples. The Campylobacter densities were significantly higher (P Cladophora samples than in the ditchside Cladophora samples. DNA fingerprint analyses indicated that genotypically identical Salmonella isolates were associated with geographically and temporally distinct Cladophora samples. However, Campylobacter isolates were genetically diverse. Since animal hosts are thought to be the primary habitat for Campylobacter and Salmonella species, our results suggest that Cladophora is a

Multiple mechanisms enable invasive species to suppress native species.

Science.gov (United States)

Bennett, Alison E; Thomsen, Meredith; Strauss, Sharon Y

2011-07-01

Invasive plants represent a significant threat to ecosystem biodiversity. To decrease the impacts of invasive species, a major scientific undertaking of the last few decades has been aimed at understanding the mechanisms that drive invasive plant success. Most studies and theories have focused on a single mechanism for predicting the success of invasive plants and therefore cannot provide insight as to the relative importance of multiple interactions in predicting invasive species' success. We examine four mechanisms that potentially contribute to the success of invasive velvetgrass Holcus lanatus: direct competition, indirect competition mediated by mammalian herbivores, interference competition via allelopathy, and indirect competition mediated by changes in the soil community. Using a combination of field and greenhouse approaches, we focus on the effects of H. lanatus on a common species in California coastal prairies, Erigeron glaucus, where the invasion is most intense. We found that H. lanatus had the strongest effects on E. glaucus via direct competition, but it also influenced the soil community in ways that feed back to negatively influence E. glaucus and other native species after H. lanatus removal. This approach provided evidence for multiple mechanisms contributing to negative effects of invasive species, and it identified when particular strategies were most likely to be important. These mechanisms can be applied to eradication of H. lanatus and conservation of California coastal prairie systems, and they illustrate the utility of an integrated set of experiments for determining the potential mechanisms of invasive species' success.

Estudio preliminar de las algas de la zona de Pucallpa departamento de Loreto

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Haydée Montoya T.

2014-06-01

Full Text Available Este trabajo reporto 17 géneros y 27 especies de algas de agua dulce colectadas en Pucallpa, Departamento de Loreto. Los siguientes especies de CYANOPHYTA y CHLOROPHYTA son nuevos reportes paro lo flora peruano: Chroococcus minor, Microspora tumidula, Cylindrocystis brebissonii, Closterium baillyanum, Closterium johnnsonii, Euostrum luetkemuellerii, Euastrum paulense, Cosmarium contractum, Casmorium punctulotum, Desmidium optogonum y Phymatodocis nordstedtiona.

Species climate range influences hydraulic and stomatal traits in Eucalyptus species.

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Bourne, Aimee E; Creek, Danielle; Peters, Jennifer M R; Ellsworth, David S; Choat, Brendan

2017-07-01

Plant hydraulic traits influence the capacity of species to grow and survive in water-limited environments, but their comparative study at a common site has been limited. The primary aim of this study was to determine whether selective pressures on species originating in drought-prone environments constrain hydraulic traits among related species grown under common conditions. Leaf tissue water relations, xylem anatomy, stomatal behaviour and vulnerability to drought-induced embolism were measured on six Eucalyptus species growing in a common garden to determine whether these traits were related to current species climate range and to understand linkages between the traits. Hydraulically weighted xylem vessel diameter, leaf turgor loss point, the water potential at stomatal closure and vulnerability to drought-induced embolism were significantly ( P Eucalyptus trees has important implications for the limits of species responses to changing environmental conditions and thus for species survival and distribution into the future, and yields new information for physiological models. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Palpi aplenty: New species in the Chrysotus longipalpus species group (Diptera: Dolichopodidae)

Science.gov (United States)

Justin B. Runyon; Renato S. Capellari

2018-01-01

Four new Nearctic species belonging to the Chrysotus longipalpus species group are described: Chrysotus keyensis sp. nov. (Florida), Chrysotus mccreadiei sp. nov. (Alabama), Chrysotus mystax sp. nov. (Alabama), and Chrysotus plumarista sp. nov. (Alabama). This brings the number of known species in this group to twelve. A key to species of males of the C. longipalpus...

Species recovery in the United States: Increasing the effectiveness of the Endangered Species Act

Science.gov (United States)

Daniel M. Evans; Judy P. Che-Castaldo; Deborah Crouse; Frank W. Davis; Rebecca Epanchin-Niell; Curtis H. Flather; R. Kipp Frohlich; Dale D. Goble; Ya-Wei Li; Timothy D. Male; Lawrence L. Master; Matthew P. Moskwik; Maile C. Neel; Barry R. Noon; Camille Parmesan; Mark W. Schwartz; J. Michael Scott; Byron K. Williams

2016-01-01

The Endangered Species Act (ESA) has succeeded in shielding hundreds of species from extinction and improving species recovery over time. However, recovery for most species officially protected by the ESA - i.e., listed species - has been harder to achieve than initially envisioned. Threats to species are persistent and pervasive, funding has been insufficient...

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.

Valuing local endangered species. The role of intra-species substitutes

Energy Technology Data Exchange (ETDEWEB)

Loureiro, Maria L. [Department of Economic Analysis, Universidade de Santiago (Spain); IDEGA, Universidade de Santiago de Compostela, Campus Sur, Avda das Ciencias, S/N. 15782, Santiago de Compostela (Spain); Ojea, Elena [IDEGA, Universidade de Santiago de Compostela, Campus Sur, Avda das Ciencias, S/N. 15782, Santiago de Compostela (Spain)

2008-12-01

Valuation of endangered species is important in many circumstances, and particularly when assessing the impact of large accidental oil spills. Previous studies have tested the effects of including in the contingent valuation survey reminders about the existence of diverse substitutes (in terms of other natural resources also in danger of extinction in the same area, other programs to be valued, or alternative uses of money). We include a reminder about the existence of the same biological species not being under danger of extinction elsewhere. We believe this reminder allows individuals to make an easy assessment of the biological scarcity of the species they are supposed to value. Thus, the key difference with previous studies is that valuation of endangered species is combined with an assessment of preferences towards conservation of local and native species. Our WTP results are not sensitive to the information provided about other foreign substitutes. Implications of this finding are discussed. (author)

Valuing local endangered species. The role of intra-species substitutes

International Nuclear Information System (INIS)

Loureiro, Maria L.; Ojea, Elena

2008-01-01

Valuation of endangered species is important in many circumstances, and particularly when assessing the impact of large accidental oil spills. Previous studies have tested the effects of including in the contingent valuation survey reminders about the existence of diverse substitutes (in terms of other natural resources also in danger of extinction in the same area, other programs to be valued, or alternative uses of money). We include a reminder about the existence of the same biological species not being under danger of extinction elsewhere. We believe this reminder allows individuals to make an easy assessment of the biological scarcity of the species they are supposed to value. Thus, the key difference with previous studies is that valuation of endangered species is combined with an assessment of preferences towards conservation of local and native species. Our WTP results are not sensitive to the information provided about other foreign substitutes. Implications of this finding are discussed. (author)

Detection of cryptic species

International Nuclear Information System (INIS)

Cockburn, A.F.; Jensen, T.; Seawright, J.A.

1998-01-01

Morphologically similar cryptic species are common in insects. In Anopheles mosquitoes morphologically described species are complexes of cryptic species. Cryptic species are of great practical importance for two reasons: first, one or more species of the complex might not be a pest and control efforts directed at the complex as a whole would therefore be partly wasted; and second, genetic (and perhaps biological) control strategies directed against one species of the complex would not affect other species of the complex. At least one SIT effort has failed because the released sterile insect were of a different species and therefore did not mate with the wild insects being targeted. We use a multidisciplinary approach for detection of cryptic species complexes, focusing first on identifying variability in wild populations using RFLPs of mitochondrial and ribosomal RNA genes (mtDNA and rDNA); followed by confirmation using a variety of other techniques. For rapid identification of wild individuals of field collections, we use a DNA dot blot assay. DNA probes can be isolated by differential screening, however we are currently focusing on the sequencing of the rDNA extragenic spacers. These regions are repeated several hundred times per genome in mosquitoes and evolve rapidly. Molecular drive tends to keen the individual genes homogeneous within a species. (author)

Species-specific associations between overstory and understory tree species in a semideciduous tropical forest

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Flaviana Maluf Souza

2015-03-01

Full Text Available We investigated the occurrence of associations between overstory and understory tree species in a semideciduous tropical forest. We identified and measured all trees of nine canopy species with diameter at breast height ≥4.8 cm in a 10.24 ha plot and recorded all individuals beneath their canopies ("understory individuals" within the same diameter class. The total density of understory individuals did not significantly differ under different overstory species. One overstory species (Ceiba speciosa showed higher understory species richness compared with five other species. There was a strong positive association between three overstory species (Esenbeckia leiocarpa, Savia dictyocarpa, and C. speciosa and the density of seven understory species (Balfourodendron riedelianum, Chrysophyllum gonocarpum, E. leiocarpa, Holocalyx balansae, Machaerium stipitatum, Rhaminidium elaeocarpum, and S. dictyocarpa. These results probably reflect the outcome of a complex set of interactions including facilitation and competition, and further studies are necessary to better understand the magnitude and type of the effects of individual overstory species on understory species. The occurrence of species-specific associations shown here reinforces the importance of non-random processes in structuring plant communities and suggest that the influence of overstory species on understory species in high-diversity forests may be more significant than previously thought.

Species of Wadicosa (Araneae, Lycosidae): a new species from Madagascar.

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Kronestedt, Torbjörn

2017-05-10

Since establishing the wolf spider genus Wadicosa Zyuzin, 1985 (Zyuzin 1985), eleven species have been accepted in it, either by transfer from Lycosa Latreille, 1804 or Pardosa C.L. Koch, 1847 or by original designation (WSC 2017). However, according to Kronestedt (1987), additional species wait to be formally transferred to Wadicosa. The genus is restricted to the Old World, with one species, Wadicosa jocquei Kronestedt, 2015, recently described from Madagascar and surrounding islands.

Invasive non-native species' provision of refugia for endangered native species.

Science.gov (United States)

Chiba, Satoshi

2010-08-01

The influence of non-native species on native ecosystems is not predicted easily when interspecific interactions are complex. Species removal can result in unexpected and undesired changes to other ecosystem components. I examined whether invasive non-native species may both harm and provide refugia for endangered native species. The invasive non-native plant Casuarina stricta has damaged the native flora and caused decline of the snail fauna on the Ogasawara Islands, Japan. On Anijima in 2006 and 2009, I examined endemic land snails in the genus Ogasawarana. I compared the density of live specimens and frequency of predation scars (from black rats [Rattus rattus]) on empty shells in native vegetation and Casuarina forests. The density of land snails was greater in native vegetation than in Casuarina forests in 2006. Nevertheless, radical declines in the density of land snails occurred in native vegetation since 2006 in association with increasing predation by black rats. In contrast, abundance of Ogasawarana did not decline in the Casuarina forest, where shells with predation scars from rats were rare. As a result, the density of snails was greater in the Casuarina forest than in native vegetation. Removal of Casuarina was associated with an increased proportion of shells with predation scars from rats and a decrease in the density of Ogasawarana. The thick and dense litter of Casuarina appears to provide refugia for native land snails by protecting them from predation by rats; thus, eradication of rats should precede eradication of Casuarina. Adaptive strategies, particularly those that consider the removal order of non-native species, are crucial to minimizing the unintended effects of eradication on native species. In addition, my results suggested that in some cases a given non-native species can be used to mitigate the impacts of other non-native species on native species.

Detection of cryptic species

Energy Technology Data Exchange (ETDEWEB)

Cockburn, A F; Jensen, T; Seawright, J A [United States Dept. of Agriculture, Agricultural Research Service, Medical and Veterinary Entomology Research Lab., Gainesville, FL (United States)

1998-01-01

Morphologically similar cryptic species are common in insects. In Anopheles mosquitoes morphologically described species are complexes of cryptic species. Cryptic species are of great practical importance for two reasons: first, one or more species of the complex might not be a pest and control efforts directed at the complex as a whole would therefore be partly wasted; and second, genetic (and perhaps biological) control strategies directed against one species of the complex would not affect other species of the complex. At least one SIT effort has failed because the released sterile insect were of a different species and therefore did not mate with the wild insects being targeted. We use a multidisciplinary approach for detection of cryptic species complexes, focusing first on identifying variability in wild populations using RFLPs of mitochondrial and ribosomal RNA genes (mtDNA and rDNA); followed by confirmation using a variety of other techniques. For rapid identification of wild individuals of field collections, we use a DNA dot blot assay. DNA probes can be isolated by differential screening, however we are currently focusing on the sequencing of the rDNA extragenic spacers. These regions are repeated several hundred times per genome in mosquitoes and evolve rapidly. Molecular drive tends to keen the individual genes homogeneous within a species. (author). 11 refs, 2 figs, 2 tabs.

Cladophora (Chlorophyta) spp. harbor human bacterial pathogens in nearshore water of Lake Michigan

Science.gov (United States)

Ishii, S.; Yan, T.; Shively, D.A.; Byappanahalli, M.N.; Whitman, R.L.; Sadowsky, M.J.

2006-01-01

Cladophora glomerata, a macrophytic green alga, is commonly found in the Great Lakes, and significant accumulations occur along shorelines during the summer months. Recently, Cladophora has been shown to harbor high densities of the fecal indicator bacteria Escherichia coli and enterococci. Cladophora may also harbor human pathogens; however, until now, no studies to address this question have been performed. In the present study, we determined whether attachedCladophora, obtained from the Lake Michigan and Burns Ditch (Little Calumet River, Indiana) sides of a breakwater during the summers of 2004 and 2005, harbored the bacterial pathogens Shiga toxin-producing Escherichia coli (STEC),Salmonella, Shigella, and Campylobacter. The presence of potential pathogens and numbers of organisms were determined by using cultural methods and by using conventional PCR, most-probable-number PCR (MPN-PCR), and quantitative PCR (QPCR) performed with genus- and toxin-specific primers and probes. WhileShigella and STEC were detected in 100% and 25%, respectively, of the algal samples obtained near Burns Ditch in 2004, the same pathogens were not detected in samples collected in 2005. MPN-PCR and QPCR allowed enumeration of Salmonella in 40 to 80% of the ditch- and lakeside samples, respectively, and the densities were up to 1.6 × 103 cells per g Cladophora. Similarly, these PCR methods allowed enumeration of up to 5.4 × 102 Campylobacter cells/gCladophora in 60 to 100% of lake- and ditchside samples. The Campylobacterdensities were significantly higher (P fingerprint analyses indicated that genotypically identical Salmonella isolates were associated with geographically and temporally distinct Cladophora samples. However, Campylobacter isolates were genetically diverse. Since animal hosts are thought to be the primary habitat forCampylobacter and Salmonella species, our results suggest that Cladophora is a likely secondary habitat for pathogenic

Determining Microeukaryotic Plankton Community around Xiamen Island, Southeast China, Using Illumina MiSeq and PCR-DGGE Techniques.

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Lingyu Yu

Full Text Available Microeukaryotic plankton are important components of aquatic environments and play key roles in marine microbial food webs; however, little is known about their genetic diversity in subtropical offshore areas. Here we examined the community composition and genetic diversity of the microeukaryotic plankton in Xiamen offshore water by PCR-DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis, clone-based sequencing and Illumina based sequencing. The Illumina MiSeq sequencing revealed a much (approximately two orders of magnitude higher species richness of the microeukaryotic community than DGGE, but there were no significant difference in species richness and diversity among the northern, eastern, southern or western stations based on both methods. In this study, Copepoda, Ciliophora, Chlorophyta, Dinophyceae, Cryptophyta and Bacillariophyta (diatoms were the dominant groups even though diatoms were not detected by DGGE. Our Illumina based results indicated that two northern communities (sites N2 and N3 were significantly different from others in having more protozoa and fewer diatoms. Redundancy analysis (RDA showed that both temperature and salinity were the significant environmental factors influencing dominant species communities, whereas the full microeukaryotic community appeared to be affected by a complex of environmental factors. Our results suggested that extensive sampling combined with more deep sequencing are needed to obtain the complete diversity of the microeukaryotic community, and different diversity patterns for both abundant and rare taxa may be important in evaluating the marine ecosystem health.

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.

Life cycle, feeding and adaptive strategy implications on the co-occurrence of Argyrodiaptomus furcatus and Notodiaptomus iheringi in Lobo-Broa Reservoir (SP, Brazil

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RIETZLER A. C.

2002-01-01

Full Text Available The population dynamics, life cycle and feeding of Argyrodiaptomus furcatus and Notodiaptomus iheringi, were studied in Broa reservoir from August 1988 to August 1989, period when a replacement of A. furcatus by N. iheringi was observed. Some abiotic factors such as temperature, dissolved oxygen, pH and conductivity were measured to characterize the limnological conditions of the reservoir. Also, phytoplankton composition was analyzed and related to the feeding of the two species. Experimental data on developmental time and reproduction of A. furcatus and N. iheringi under different temperatures showed that lower temperatures were responsible for density decreasing of both populations in the reservoir during the dry season. Chlorophyta and Chrysophyta smaller than 20 mum were the most abundant phytoplankton groups in the reservoir as well as in the gut content of A. furcatus and N. iheringi, representing an important food source for both species. The temporary disappearance of Argyrodiaptomus furcatus, observed between 1988 and 1989 and its replacement by Notodiaptomus iheringi was related to mining activities upstream, modifying the water turbidity, pH and conductivity. However, the reappearance and maintenance of A. furcatus for another ten years and a recent replacement re-incidence indicates that these two calanoids do not coexist in this environment. Adaptive strategies of both species, related to changes in environmental conditions, are discussed. Probably, Argyrodiaptomus furcatus is an indicator of less eutrophic environments, while Notodiaptomus iheringi of more eutrophic systems.

Invasive Species Science Branch: research and management tools for controlling invasive species

Science.gov (United States)

Reed, Robert N.; Walters, Katie D.

2015-01-01

Invasive, nonnative species of plants, animals, and disease organisms adversely affect the ecosystems they enter. Like “biological wildfires,” they can quickly spread and affect nearly all terrestrial and aquatic ecosystems. Invasive species have become one of the greatest environmental challenges of the 21st century in economic, environmental, and human health costs, with an estimated effect in the United States of more than $120 billion per year. Managers of the Department of the Interior and other public and private lands often rank invasive species as their top resource management problem. The Invasive Species Science Branch of the Fort Collins Science Center provides research and technical assistance relating to management concerns for invasive species, including understanding how these species are introduced, identifying areas vulnerable to invasion, forecasting invasions, and developing control methods. To disseminate this information, branch scientists are developing platforms to share invasive species information with DOI cooperators, other agency partners, and the public. From these and other data, branch scientists are constructing models to understand and predict invasive species distributions for more effective management. The branch also has extensive herpetological and population biology expertise that is applied to harmful reptile invaders such as the Brown Treesnake on Guam and Burmese Python in Florida.

Evaluating species richness: biased ecological inference results from spatial heterogeneity in species detection probabilities

Science.gov (United States)

McNew, Lance B.; Handel, Colleen M.

2015-01-01

Accurate estimates of species richness are necessary to test predictions of ecological theory and evaluate biodiversity for conservation purposes. However, species richness is difficult to measure in the field because some species will almost always be overlooked due to their cryptic nature or the observer's failure to perceive their cues. Common measures of species richness that assume consistent observability across species are inviting because they may require only single counts of species at survey sites. Single-visit estimation methods ignore spatial and temporal variation in species detection probabilities related to survey or site conditions that may confound estimates of species richness. We used simulated and empirical data to evaluate the bias and precision of raw species counts, the limiting forms of jackknife and Chao estimators, and multi-species occupancy models when estimating species richness to evaluate whether the choice of estimator can affect inferences about the relationships between environmental conditions and community size under variable detection processes. Four simulated scenarios with realistic and variable detection processes were considered. Results of simulations indicated that (1) raw species counts were always biased low, (2) single-visit jackknife and Chao estimators were significantly biased regardless of detection process, (3) multispecies occupancy models were more precise and generally less biased than the jackknife and Chao estimators, and (4) spatial heterogeneity resulting from the effects of a site covariate on species detection probabilities had significant impacts on the inferred relationships between species richness and a spatially explicit environmental condition. For a real dataset of bird observations in northwestern Alaska, the four estimation methods produced different estimates of local species richness, which severely affected inferences about the effects of shrubs on local avian richness. Overall, our results

Multi-species biofilm of Candida albicans and non-Candida albicans Candida species on acrylic substrate

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Apurva K Pathak

2012-02-01

Full Text Available OBJECTIVE: In polymicrobial biofilms bacteria extensively interact with Candida species, but the interaction among the different species of the Candida is yet to be completely evaluated. In the present study, the difference in biofilm formation ability of clinical isolates of four species of Candida in both single-species and multi-species combinations on the surface of dental acrylic resin strips was evaluated. MATERIAL AND METHODS: The species of Candida, isolated from multiple species oral candidiasis of the neutropenic patients, were used for the experiment. Organisms were cultured on Sabouraud dextrose broth with 8% glucose (SDB. Biofilm production on the acrylic resins strips was determined by crystal violet assay. Student's t-test and ANOVA were used to compare in vitro biofilm formation for the individual species of Candida and its different multi-species combinations. RESULTS: In the present study, differences between the mean values of the biofilm-forming ability of individual species (C. glabrata>C. krusei>C. tropicalis>C. albicans and in its multi-species' combinations (the highest for C. albicans with C. glabrata and the lowest for all the four species combination were reported. CONCLUSIONS: The findings of this study showed that biofilm-forming ability was found greater for non-Candida albicans Candida species (NCAC than for C. albicans species with intra-species variation. Presence of C. albicans in multi-species biofilms increased, whereas; C. tropicalis decreased the biofilm production with all other NCAC species.

Separation of chemical species

International Nuclear Information System (INIS)

Rentzepis, P.M.

1977-01-01

Isotopic separation is accomplished by (1) a second photon irradiation step for selective ionization of a first isotopic species and (2) selective precipitation of a generally immiscible liquid from the saturating vapor phase on the ionized species. The first photon corresponds with a sharply defined spectral portion of the irradiation which exclusively excites the first species to a vibrational level. The second photon further excites this species to its ionization level. Selective precipitation is by coulombic attraction between the ionized species and the vapor. The procedure is applicable to any vapor phase ionizable material

Biogeography of Aegagropila linnaei (Cladophorophyceae, Chlorophyta): a widespread freshwater alga with low effective dispersal potential shows a glacial imprint in its distribution

NARCIS (Netherlands)

Boedeker, C.; Eggert, A.; Immers, A.; Wakana, I.

2010-01-01

Aim:Aegagropila linnaei is a freshwater macroalga that is generally regarded as a rare species. It is apparently absent from large but seemingly suitable areas of the Northern Hemisphere, implying a limited dispersal potential and an imprint of Pleistocene glaciations in its biogeography. However,

New data on distribution, morphology and ecology of Oedogonium capillare Kützing ex Hirn (Oedogoniales, Chlorophyta in Poland

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Marta Pikosz

2015-12-01

Full Text Available Algological investigations were focused on taxonomy, chorology and ecology of threatened filamentous green alga species in Poland. Studies on Oedogonium capillare Kützing ex Hirn growing in large quantities in association with Cladophora rivularis (Linnaeus Hoek in pond were conducted. The aim of these studies was to describe the distribution, ecology and morphology of O. capillare as part of a more comprehensive study of this filamentous green alga. It is the eighth record in Poland for O. capillare. Filaments of O. capillare were grown over a wide pH range (7.3-9.6 and in high variability of nutrients. Vegetative cells, oogonia and antheridia were observed, which allowed taxonomic identification. O. capillare occurs in eutrophic waters which requires protection of its habitat.

Alien species recorded in the United Arab Emirates: an initial list of terrestrial and freshwater species

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Pritpal Soorae

2015-10-01

Full Text Available Little is documented on the alien terrestrial and freshwater species in the United Arab Emirates. To address this, an assessment of terrestrial and freshwater alien species was conducted using various techniques such as a questionnaire, fieldwork data, networking with relevant people, and a detailed literature review. The results of the initial assessment show that there are 146 alien species recorded in the following seven major taxonomic groups: invertebrates 49 species, freshwater fish five species, amphibian one species, reptiles six species, birds 71 species, mammals six species and plants eight species. To inform decision makers a full list of the 146 species identified in this assessment is presented. 

Linking Keystone Species and Functional Groups: A New Operational Definition of the Keystone Species Concept

OpenAIRE

Robert D. Davic

2003-01-01

The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups ...

The functional biogeography of species

DEFF Research Database (Denmark)

Carstensen, Daniel W.; Dalsgaard, Bo; Svenning, Jens-Christian

2013-01-01

Biogeographical systems can be analyzed as networks of species and geographical units. Within such a biogeographical network, individual species may differ fundamentally in their linkage pattern, and therefore hold different topological roles. To advance our understanding of the relationship betw...... to distributions at the local community level. We finally discuss how our biogeographical species roles may correspond to the stages of the taxon cycle and other prominent theories of species assembly.......Biogeographical systems can be analyzed as networks of species and geographical units. Within such a biogeographical network, individual species may differ fundamentally in their linkage pattern, and therefore hold different topological roles. To advance our understanding of the relationship...... between species traits and large-scale species distribution patterns in archipelagos, we use a network approach to classify birds as one of four biogeographical species roles: peripherals, connectors, module hubs, and network hubs. These roles are based upon the position of species within the modular...

Overview on Biological Activities and Molecular Characteristics of Sulfated Polysaccharides from Marine Green Algae in Recent Years

Science.gov (United States)

Wang, Lingchong; Wang, Xiangyu; Wu, Hao; Liu, Rui

2014-01-01

Among the three main divisions of marine macroalgae (Chlorophyta, Phaeophyta and Rhodophyta), marine green algae are valuable sources of structurally diverse bioactive compounds and remain largely unexploited in nutraceutical and pharmaceutical areas. Recently, a great deal of interest has been developed to isolate novel sulfated polysaccharides (SPs) from marine green algae because of their numerous health beneficial effects. Green seaweeds are known to synthesize large quantities of SPs and are well established sources of these particularly interesting molecules such as ulvans from Ulva and Enteromorpha, sulfated rhamnans from Monostroma, sulfated arabinogalactans from Codium, sulfated galacotans from Caulerpa, and some special sulfated mannans from different species. These SPs exhibit many beneficial biological activities such as anticoagulant, antiviral, antioxidative, antitumor, immunomodulating, antihyperlipidemic and antihepatotoxic activities. Therefore, marine algae derived SPs have great potential for further development as healthy food and medical products. The present review focuses on SPs derived from marine green algae and presents an overview of the recent progress of determinations of their structural types and biological activities, especially their potential health benefits. PMID:25257786

Diet of Agonostomus monticola (Pisces: Mugilidae in the Río Ayuquila, Sierra de Manantlán Biosphere Reserve, México

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Claudia Isela Torres-Navarro

1999-12-01

Full Text Available We quantified the diet of Agonostomus monticola during the wet and dry seasons of 1990 in a 15 km reach of the Río Ayuquila, a Pacific tributary of west-central México. The species consumed 32 animal and 9 plant families, with aquatic insects (mainly Diptera, Ephemeroptera, and Trichoptera and algae (mainly Chlorophyta as primary prey. Animal material dominated the diet in the wet season but was only slightly more important than plant material in the dry season. Animal material increased in importance with fish size for specimens 151-300 mm total length. Río Ayuquila A. monticola ate fewer shrimp, Odonate insects, fish, and fruit than other studied populations. The broad diet of A. monticola suggests that it is an opportunistic feeder.Se cuantificó la dieta del pez Agonostomus monticola en 1990 en México. La dieta es oportunista e incluyó 32 familias de animales y nueve de plantas, pero dominó el alimento de origen animal, especialmente en individuos de 151-300 mm de longitud

Studies on 232Th and 238U levels in marine algae collected from the coast of Niigata Prefecture

International Nuclear Information System (INIS)

Kato, Kenji; Tonouchi, Shigemasa; Maruta, Fumiyuki; Ebata, Hidekazu

2001-01-01

To evaluate the properties of algae to concentrate radioactive elements, 14 species of algae like Sargassum were collected in the Prefecture and analyzed for their 232 Th and 238 U levels with Yokogawa HP4500 ICP-MS apparatus. The places of collection included those near the water discharge of an atomic power station. Mean 232 Th and 238 U levels were found to be 120 and 260 ng/g dry wt, respectively, and Phaeophyta showed more than several times higher 238 U level than Chlorophyta and Rhodophyta. There was no clear difference in 232 Th levels. No difference between places of collection was observed in Sargassum 232 Th or 238 U level. Adsorption of 232 Th particle to and incorporation of soluble 238 U into algae body were suggested. Mean 232 Th and 238 U radioactivities were found 73 and 510 μBq/g wet wt, respectively, and the respective annual committed effective doses, 0.2 and 0.3 μSv, calculated from those values were confirmed to be enough lower than the annual public dose limit, 1 mSv. (K.H.)

Similarity microalgal epiphyte composition on seagrass of Enhalus acoroides and Thalasia hemprichii from different waters

Science.gov (United States)

Hartati, R.; Zainuri, M.; Ambariyanto, A.; Widianingsih; Trianto, A.; Mahendrajaya, R. T.

2018-03-01

The epiphytes are all autotrophic organisms that are permanently attached to rhizomes, roots, and leaves of seagrasses. The epiphyte is an important primary producer for the seagrass ecosystem and contributes significantly to the food chain. This study aims to identify the composition of microepiphyte algae on Enhalus acoroides and Thalassia hemprichii and their similarity levels of both compositions. The 20 leaves samples of E. acoroides and T. hemprichii were observed. The epiphytic microalgae which found on the surface of the seagrass leaves were scrapped, collected in a bottle sample, and fixed with 70 % alcohol and identified into genera. The relation of epiphytic microalgal genera to the location and species of seagrass was analyzed using similarity analysis. The Chrysophyta, Cyanophyta, and Chlorophyta epiphytic microalgal were found. There were similarity variations of the microalgal epiphyte in seagrass of E. acoroides and T. hemprichii and seagrass habitat sites. Morphology and seagrass life affects the abundance and diversity of the epiphytic microalgal attached to the seagrass and it may be associated with the epiphytic lifetime in the seagrass.

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.)

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.

Meteorological effects on variation of airborne algae in Mexico

Science.gov (United States)

Rosas, Irma; Roy-Ocotla, Guadalupe; Mosiño, Pedro

1989-09-01

Sixteen species of algae were collected from 73.8 m3 of air. Eleven were obtained in Minatitlán and eleven in México City. The data show that similar diversity occurred between the two localities, in spite of the difference in altitude. This suggests that cosmopolitan airborne microorganisms might have been released from different sources. Three major algal divisions (Chlorophyta, Cyanophyta and Chrysophyta) formed the airborne algal group. Also, a large concentration of 2220 algae m-3 was found near sea-level, while lower amounts were recorded at the high altitude of México City. The genera Scenedesmus, Chlorella and Chlorococcum dominated. Striking relationships were noted between the concentration of airborne green and blue-green algae, and meteorological conditions such as rain, vapour pressure, temperature and winds for different altitudes. In Minatitlán a linear relationship was established between concentration of algae and both vapour pressure (mbar) and temperature (° C), while in México City the wind (m s-1) was associated with variations in the algal count.

Linking Keystone Species and Functional Groups: A New Operational Definition of the Keystone Species Concept

Directory of Open Access Journals (Sweden)

Robert D. Davic

2003-07-01

Full Text Available The concept of the "keystone species" is redefined to allow for the a priori prediction of these species within ecosystems. A keystone species is held to be a strongly interacting species whose top-down effect on species diversity and competition is large relative to its biomass dominance within a functional group. This operational definition links the community importance of keystone species to a specific ecosystem process, e.g., the regulation of species diversity, within functional groups at lower trophic levels that are structured by competition for a limited resource. The a priori prediction of keystone species has applied value for the conservation of natural areas.

Invading species in the Eel River, California: Successes, failures, and relationships with resident species

Science.gov (United States)

Brown, L.R.; Moyle, P.B.

1997-01-01

We examined invasions of non-native fishes into the Eel River, California. At least 16 species of fish have been introduced into the drainage which originally supported 12-14 fish species. Our study was prompted by the unauthorized introduction in 1979 of Sacramento squawfish, Ptychocheilus grandis, a large predatory cyprinid. From 1986 to 1990, we conducted growth and diet studies of squaw fish, conducted intensive surveys of the distribution and habitat associations of both native and introduced species, and examined the nature of species-habitat and interspecies relationships. We found no evidence for increased growth or expanded feeding habits, compared to native populations, of Sacramento squawfish as they invaded the Eel River drainage. Ten of the introduced species were well established, with four species limited to a reservoir and six species established in streams. The success or failure of introductions of stream species appeared to be a function of the ability of a species to survive the fluctuating, highly seasonal, flow regime. The present mixture of native and exotic species has not formed stable fish assemblages but it seems likely that four habitat-associated assemblages will develop. The overall effect of the successful species introductions has been to assemble a group of species, with some exceptions, that are native to and occur together in many California streams. The assemblages now forming are similar to those found in other California streams. The assemblage characterized by squawfish and suckers is likely to be resistant to invasion, in the absence of human caused habitat modifications.

Species accounts. Chapter 4

Science.gov (United States)

Margaret K. Trani; W. Mark Ford; Brian R., eds. Chapman

2007-01-01

Narrative accounts for each species are presented by several authors in a consistent format to convey specific information relative to that mammal. The orders are arranged phylogenetically; families and species are arranged alphabetically to facilitate finding a particular species.

Genetic sorting of subordinate species in grassland modulated by intraspecific variation in dominant species.

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Danny J Gustafson

Full Text Available Genetic variation in a single species can have predictable and heritable effects on associated communities and ecosystem processes, however little is known about how genetic variation of a dominant species affects plant community assembly. We characterized the genetic structure of a dominant grass (Sorghastrum nutans and two subordinate species (Chamaecrista fasciculata, Silphium integrifolium, during the third growing season in grassland communities established with genetically distinct (cultivated varieties or local ecotypes seed sources of the dominant grasses. There were genetic differences between subordinate species growing in the cultivar versus local ecotype communities, indicating that intraspecific genetic variation in the dominant grasses affected the genetic composition of subordinate species during community assembly. A positive association between genetic diversity of S. nutans, C. fasciculata, and S. integrifolium and species diversity established the role of an intraspecific biotic filter during community assembly. Our results show that intraspecific variation in dominant species can significantly modulate the genetic composition of subordinate species.

Biodiversity in the cyclic competition system of three species according to the emergence of mutant species

Science.gov (United States)

Park, Junpyo

2018-05-01

Understanding mechanisms which promote or hinder existing ecosystems are important issues in ecological sciences. In addition to fundamental interactions such as competition and migration among native species, existing ecosystems can be easily disturbed by external factors, and the emergence of new species may be an example in such cases. The new species which does not exist in a current ecosystem can be regarded as either alien species entered from outside or mutant species born by mutation in existing normal species. Recently, as existing ecosystems are getting influenced by various physical/chemical external factors, mutation due to anthropogenic and environmental factors can occur more frequently and is thus attracting much attention for the maintenance of ecosystems. In this paper, we consider emergences of mutant species among self-competing three species in the cyclic dominance. By defining mutation as the birth of mutant species, we investigate how mutant species can affect biodiversity in the existing ecosystem. Through microscopic and macroscopic approaches, we have found that the society of existing normal species can be disturbed by mutant species either the society is maintained accompanying with the coexistence of all species or jeopardized by occupying of mutant species. Due to the birth of mutant species, the existing society may be more complex by constituting two different groups of normal and mutant species, and our results can be contributed to analyze complex ecosystems of many species. We hope our findings may propose a new insight on mutation in cyclic competition systems of many species.

Attempted integration of multiple species of turaco into a mixed-species aviary.

Science.gov (United States)

Valuska, Annie J; Leighty, Katherine A; Ferrie, Gina M; Nichols, Valerie D; Tybor, Cheryl L; Plassé, Chelle; Bettinger, Tamara L

2013-03-01

Mixed-species exhibits offer a variety of benefits but can be challenging to maintain due to difficulty in managing interspecific interactions. This is particularly true when little has been documented on the behavior of the species being mixed. This was the case when we attempted to house three species of turaco (family: Musophagidae) together with other species in a walk-through aviary. To learn more about the behavior of great blue turacos, violaceous turacos, and white-bellied gray go-away birds, we supplemented opportunistic keeper observations with systematic data collection on their behavior, location, distance from other birds, and visibility to visitors. Keepers reported high levels of aggression among turacos, usually initiated by a go-away bird or a violaceous turaco. Most aggression occurred during feedings or when pairs were defending nest sites. Attempts to reduce aggression by temporarily removing birds to holding areas and reintroducing them days later were ineffective. Systematic data collection revealed increased social behavior, including aggression, during breeding season in the violaceous turacos, as well as greater location fidelity. These behavioral cues may be useful in predicting breeding behavior in the future. Ultimately, we were only able to house three species of turaco together for a short time, and prohibitively high levels of conflict occurred when pairs were breeding. We conclude that mixing these three turaco species is challenging and may not be the most appropriate housing situation for them, particularly during breeding season. However, changes in turaco species composition, sex composition, or exhibit design may result in more compatible mixed-turaco species groups. © 2012 Wiley Periodicals, Inc.

Endangered Species Act

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend. The U.S. Fish and Wildlife...

Species diversity modulates predation

NARCIS (Netherlands)

Kratina, P.; Vos, M.; Anholt, B.R.

2007-01-01

Predation occurs in a context defined by both prey and non-prey species. At present it is largely unknown how species diversity in general, and species that are not included in a predator's diet in particular, modify predator–prey interactions.Therefore we studied how both the density and diversity

Positive feedback in species communities

NARCIS (Netherlands)

Gerla, D.J.

2012-01-01

Sometimes the eventual population densities in a species community depend on the initial densities or the arrival times of species. If arrival times determine species composition, a priority effect has occurred. Priority effects may occur if the species community exhibits alternative stable states

No universal scale-dependent impacts of invasive species on native plant species richness.

Science.gov (United States)

Stohlgren, Thomas J; Rejmánek, Marcel

2014-01-01

A growing number of studies seeking generalizations about the impact of plant invasions compare heavily invaded sites to uninvaded sites. But does this approach warrant any generalizations? Using two large datasets from forests, grasslands and desert ecosystems across the conterminous United States, we show that (i) a continuum of invasion impacts exists in many biomes and (ii) many possible species-area relationships may emerge reflecting a wide range of patterns of co-occurrence of native and alien plant species. Our results contradict a smaller recent study by Powell et al. 2013 (Science 339, 316-318. (doi:10.1126/science.1226817)), who compared heavily invaded and uninvaded sites in three biomes and concluded that plant communities invaded by non-native plant species generally have lower local richness (intercepts of log species richness-log area regression lines) but steeper species accumulation with increasing area (slopes of the regression lines) than do uninvaded communities. We conclude that the impacts of plant invasions on plant species richness are not universal.

Population genetics and cryptic species

International Nuclear Information System (INIS)

McPheron, Bruce A.

2000-01-01

Does the definition of a species matter for pest management purposes? Taxonomists provide us with tools - usually morphological characters - to identify a group of organisms that we call a species. The implication of this identification is that all of the individuals that fit the provided description are members of the species in question. The taxonomists have considered the range of variation among individuals in defining the species, but this variation is often forgotten when we take the concept of species to the level of management. Just as there is morphological variation among individuals, there is also variation in practically any character we might imagine, which has implications for the short and long term success of our management tactics. The rich literature on insecticide resistance should be a constant reminder of the fact that the pressure on pest survival and reproduction applied by our management approaches frequently leads to evolutionary changes within the pest species. The degree of variation within a particular species is a defining characteristic of that species. This level of variability may have very important implications for successful management, so it is very important to measure variation and, whenever possible, the genetic basis of that variation, in a target species. Population genetic approaches can provide evidence of genetic structure (or lack thereof) among populations of a species. These types of data can be used to discuss the movement of pest populations on a local or global scale. In other cases, we may have a complex of species that share some, but not all, characteristics. Species complexes that share morphological characters (i.e., cannot be easily distinguished) but not biological characters are referred to as sibling or cryptic species

Taxonomic composition of phytoplankton in the Vakh River (Western Siberia)

Science.gov (United States)

Skorobogatova, O. N.

2018-03-01

This paper provides data on the hydrological and hydrochemical parameters of the Vakh River in the Middle Ob region. In 2005-2008 we have identified 404 taxonomic units represented by 463 species, types and forms of algae, belonging to 140 genera, 52 families, 13 classes and 7 divisions. 386 species were identified for the first time, 141 taxa were identified as rare and 22 taxa as new for Western Siberia. Leading divisions, Bacillariophyta and Chlorophyta, make up for 78.9% of total phytoplankton diversity. Cyanobacteria, Chrysophyta and Euglenophyta form a community of 88 taxonomic units having a rank lower than genus level, and represent 19.0% of the total number. The floral role of Xanthophyta and Dinophyta is insignificant (2.1%). The main structure-forming species are 14: vegetating throughout the year (Aulacoseira italica, Asterionella formosa), summer taxa (Microcystis aeruginosa, Melosira varians, Aulacoseira granulata, Pandorina morum, Pediastrum boryanum, P. duplex, Lacunastrum gracillimum, Scenedesmus quadricauda) and summer-autumn (Microcystis pulverea, Tabellaria fenestrata, T. flocculosa, Mucidosphaerium pulchellum). The Vakh River demonstrates specific characteristics of boreal flowing waterways. The northern composition is represented in a big rate of families (44.2%) and genera (109 77.9) with one to three species. The richest genera Closterium (31 taxa), Eunotia (27 taxa), Pinnularia (22 taxa), Desmidium (11 taxa) and the family Desmidiaceae (45 taxa) ensure diversity of phytoplankton. Ecological and geographical analysis demonstrates predominance of cosmopolitan algae (56.6%). Plankton represents 44.7% of all algae, oligogalobs - 78.8% and indifferent algae – 36.7%. Water meets the requirements for β-mezosaprobian pollution zone, class of satisfactory purity (III class).

Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate.

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Cong Wang

Full Text Available Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta. Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina regardless of DIP condition. Group V (Amphidinium carterae exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine

Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate

Science.gov (United States)

Wang, Cong; Lin, Xin; Li, Ling; Lin, Senjie

2016-01-01

Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P) nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta). Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP) conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum) could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella) could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana) and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina) regardless of DIP condition. Group V (Amphidinium carterae) exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine phytoplankton

In vitro exposure of Ulva lactuca Linnaeus (Chlorophyta) to gasoline - Biochemical and morphological alterations.

Science.gov (United States)

Pilatti, Fernanda Kokowicz; Ramlov, Fernanda; Schmidt, Eder Carlos; Kreusch, Marianne; Pereira, Débora Tomazi; Costa, Christopher; de Oliveira, Eva Regina; Bauer, Cláudia M; Rocha, Miguel; Bouzon, Zenilda Laurita; Maraschin, Marcelo

2016-08-01

Refined fuels have considerable share of pollution of marine ecosystems. Gasoline is one of the most consumed fuel worldwide, but its effects on marine benthic primary producers are poorly investigated. In this study, Ulva lactuca was chosen as a biological model due to its cosmopolitan nature and tolerance to high levels and wide range of xenobiotics and our goal was to evaluate the effects of gasoline on ultrastructure and metabolism of that seaweed. The experimental design consisted of in vitro exposure of U. lactuca to four concentrations of gasoline (0.001%, 0.01%, 0.1%, and 1.0%, v/v) over 30 min, 1 h, 12 h, and 24 h, followed by cytochemical, SEM, and biochemical analysis. Increase in the number of cytoplasmic granules, loss of cell turgor, cytoplasmic shrinkage, and alterations in the mucilage were some of the ultrastructural alterations observed in thalli exposed to gasoline. Decrease in carotenoid and polyphenol contents, as well as increase of soluble sugars and starch contents were associated with the time of exposure to the xenobiotic. In combination, the results revealed important morphological and biochemical alterations in the phenotype of U. lactuca upon acute exposure to gasoline. This seaweed contain certain metabolites assigned as candidates to biomarkers of the environmental stress investigated and it is thought to be a promise species for usage in coastal ecosystems perturbation monitoring system. In addition, the findings suggest that U. lactuca is able to metabolize gasoline hydrocarbons and use them as energy source, acting as bioremediator of marine waters contaminated by petroleum derivatives. Copyright © 2016 Elsevier Ltd. All rights reserved.

Extragastric Helicobacter species

DEFF Research Database (Denmark)

On, Stephen L.W.; Hynes, S.; Wadstrom, T.

2002-01-01

The genus Helicobacter has expanded at a rapid pace and no fewer than 31 species have been named since the proposal of the genus in 1989. Of these 31 species, 22 are principally associated with extragastric niches and there is increasing interest in the role of these taxa in diseases of humans...... and animals. Substantial evidence attests to certain species playing a role in the pathogenesis of enteric, hepatic and biliary disorders and some taxa demonstrate zoonotic potential. The importance of extragastric Helicobacters is likely to be an important topic for research in the near future. Here...

Four new species of Pteromalus Swederus (Hymenoptera: Chalcidoidea: Pteromalidae) and redescriptions of three other species

NARCIS (Netherlands)

Gijswijt, M.J.

1999-01-01

A key to the European species of the Pteromalus altus group is presented. The relationship between this group and species of the genus Euphorbia (Euphorbiaceae) is confirmed. One new species: P. villosae, associated with Euphorbia villosa Waldst. & Kit.is presented. Two new species of the albipennis

Fuzzy species among recombinogenic bacteria

Directory of Open Access Journals (Sweden)

Fraser Christophe

2005-03-01

Full Text Available Abstract Background It is a matter of ongoing debate whether a universal species concept is possible for bacteria. Indeed, it is not clear whether closely related isolates of bacteria typically form discrete genotypic clusters that can be assigned as species. The most challenging test of whether species can be clearly delineated is provided by analysis of large populations of closely-related, highly recombinogenic, bacteria that colonise the same body site. We have used concatenated sequences of seven house-keeping loci from 770 strains of 11 named Neisseria species, and phylogenetic trees, to investigate whether genotypic clusters can be resolved among these recombinogenic bacteria and, if so, the extent to which they correspond to named species. Results Alleles at individual loci were widely distributed among the named species but this distorting effect of recombination was largely buffered by using concatenated sequences, which resolved clusters corresponding to the three species most numerous in the sample, N. meningitidis, N. lactamica and N. gonorrhoeae. A few isolates arose from the branch that separated N. meningitidis from N. lactamica leading us to describe these species as 'fuzzy'. Conclusion A multilocus approach using large samples of closely related isolates delineates species even in the highly recombinogenic human Neisseria where individual loci are inadequate for the task. This approach should be applied by taxonomists to large samples of other groups of closely-related bacteria, and especially to those where species delineation has historically been difficult, to determine whether genotypic clusters can be delineated, and to guide the definition of species.

Enolonium Species-Umpoled Enolates

DEFF Research Database (Denmark)

Arava, Shlomy; Kumar, Jayprakash N.; Maksymenko, Shimon

2017-01-01

Enolonium species/iodo(III) enolates of carbonyl compounds have been suggested to be intermediates in a wide variety of hypervalent iodine induced chemical transformations of ketones, including α-C-O, α-C-N, α-C-C, and alpha-carbon- halide bond formation, but they have never been characterized. We...... report that these elusive umpoled enolates may be made as discrete species that are stable for several minutes at-78 degrees C, and report the first spectroscopic identification of such species. It is shown that enolonium species are direct intermediates in C-O, C-N, C-Cl, and C-C bond forming reactions....... Our results open up chemical space for designing a variety of new transformations. We showcase the ability of enolonium species to react with prenyl, crotyl, cinnamyl, and allyl silanes with absolute regioselectivity in up to 92% yield....

Two new species of the Phanaeus endymion species group (Coleoptera, Scarabaeidae, Scarabaeinae).

Science.gov (United States)

Moctezuma, Victor; Sánchez-Huerta, José Luis; Halffter, Gonzalo

2017-01-01

Phanaeus bravoensis sp. n. is described from the coniferous-oak forests in the state of Guerrero, and P. huichol sp. n. from coniferous-oak forests and cloud forests in Jalisco and Nayarit. The new species are closely related to P. halffterorum and P. zoque respectively. Morphological trait combination, geographic distribution, and trophic habits show important differences among the studied species. A distribution map and an updated key to separate the species are included.

Bias correction in species distribution models: pooling survey and collection data for multiple species.

Science.gov (United States)

Fithian, William; Elith, Jane; Hastie, Trevor; Keith, David A

2015-04-01

Presence-only records may provide data on the distributions of rare species, but commonly suffer from large, unknown biases due to their typically haphazard collection schemes. Presence-absence or count data collected in systematic, planned surveys are more reliable but typically less abundant.We proposed a probabilistic model to allow for joint analysis of presence-only and survey data to exploit their complementary strengths. Our method pools presence-only and presence-absence data for many species and maximizes a joint likelihood, simultaneously estimating and adjusting for the sampling bias affecting the presence-only data. By assuming that the sampling bias is the same for all species, we can borrow strength across species to efficiently estimate the bias and improve our inference from presence-only data.We evaluate our model's performance on data for 36 eucalypt species in south-eastern Australia. We find that presence-only records exhibit a strong sampling bias towards the coast and towards Sydney, the largest city. Our data-pooling technique substantially improves the out-of-sample predictive performance of our model when the amount of available presence-absence data for a given species is scarceIf we have only presence-only data and no presence-absence data for a given species, but both types of data for several other species that suffer from the same spatial sampling bias, then our method can obtain an unbiased estimate of the first species' geographic range.

Redescription of four species of Mehdiella from Testudinidae, with a key to the species and discussion on the relationships among the species of this genus

Directory of Open Access Journals (Sweden)

Bouamer S.

2003-12-01

Full Text Available Four species of the genus Mehdiella Seurat, 1918 are redescribed: M. cristata Petter, 1966 and M. stylosa dollfusi Petter, 1966, parasite of Pyxix arachnoides Bell, 1827 from Madagascar, M. s. stylosa (Thapar, 1 925 and M. uncinata (Drasche, 1884, parasite of Testudo graeca Linneaus, 1758, Testudo hermanni Gmelin, 1789 and Testudo horsfieldii (Gray, 1844 from Palaearctic region. Light microscopy and scanning electron microscopy (SEM studies revealed new informations on the morphology of these species. On the basis of this morphological study, the sub-species Mehdiella stylosa dollfusi and M. s. stylosa are raised to level of species. The position of Mehdiella cristata among the species of the genus Mehdiella and the relationships among the species of the genus Mehdiella are discussed. A key to the eight valid species Mehdiella is given.

Redescription of four species of Mehdiella from Testudinidae, with a key to the species and discussion on the relationships among the species of this genus.

Science.gov (United States)

Bouamer, S; Morand, S; Kara, M

2003-12-01

Four species of the genus Mehdiella Seurat, 1918 are redescribed: M. cristata Petter, 1966 and M. stylosa dollfusi Petter, 1966, parasite of Pyxix arachnoides Bell, 1827 from Madagascar, M. s. stylosa (Thapar, 1925) and M. uncinata (Drasche, 1884), parasite of Testudo graeca Linneaus, 1758, Testudo hermanni Gmelin, 1789 and Testudo horsfieldii (Gray, 1844) from Palaearctic region. Light microscopy and scanning electron microscopy (SEM) studies revealed new informations on the morphology of these species. On the basis of this morphological study, the sub-species Mehdiella stylosa dollfusi and M. s. stylosa are raised to level of species. The position of Mehdiella cristata among the species of the genus Mehdiella and the relationships among the species of the genus Mehdiella are discussed. A key to the eight valid species Mehdiella is given.

Species composition and abundance of Brevipalpus spp. on different citrus species in Mexican orchards.

Science.gov (United States)

Salinas-Vargas, D; Santillán-Galicia, M T; Valdez-Carrasco, J; Mora-Aguilera, G; Atanacio-Serrano, Y; Romero-Pescador, P

2013-08-01

We studied the abundance of Brevipalpus spp. in citrus orchards in the Mexican states of Yucatan, Quintana Roo and Campeche. Mites were collected from 100 trees containing a mixture of citrus species where sweet orange was always the main species. Eight collections were made at each location from February 2010 to February 2011. Mites from the genus Brevipalpus were separated from other mites surveyed and their abundance and relationships with the different citrus species were quantified throughout the collection period. A subsample of 25% of the total Brevipalpus mites collected were identified to species level and the interaction of mite species and citrus species were described. Brevipalpus spp. were present on all collection dates and their relative abundance was similar on all citrus species studies. The smallest number of mites collected was during the rainy season. Brevipalpus phoenicis (Geijskes) and Brevipalpus californicus (Banks) were the only two species present and they were found in all locations except Campeche, where only B. phoenicis was present. Yucatan and Campeche are at greater risk of leprosis virus transmission than Quintana Roo because the main vector, B. phoenicis, was more abundant than B. californicus. The implications of our results for the design of more accurate sampling and control methods for Brevipalpus spp. are discussed.

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

Directory of Open Access Journals (Sweden)

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

Insular species swarm goes underground

DEFF Research Database (Denmark)

P. S. Reboleira, Ana Sofia; Enghoff, Henrik

2014-01-01

Two new species of the genus Cylindroiulus Verhoeff, 1894, C. julesvernei and C. oromii, are described from the subterranean ecosystem of Madeira Island, Portugal. Species are illustrated with photographs and diagrammatic drawings. The new species belong to the Cylindroiulus madeirae......-group, an insular species swarm distributed in the archipelagos of Madeira and the Canary Islands. We discuss the differences between the new species and their relatives and present information on the subterranean environment of Madeira. An updated overview of the subterranean biodiversity of millipedes...

Effects of 'target' plant species body size on neighbourhood species richness and composition in old-field vegetation.

Directory of Open Access Journals (Sweden)

Brandon S Schamp

Full Text Available Competition is generally regarded as an important force in organizing the structure of vegetation, and evidence from several experimental studies of species mixtures suggests that larger mature plant size elicits a competitive advantage. However, these findings are at odds with the fact that large and small plant species generally coexist, and relatively smaller species are more common in virtually all plant communities. Here, we use replicates of ten relatively large old-field plant species to explore the competitive impact of target individual size on their surrounding neighbourhoods compared to nearby neighbourhoods of the same size that are not centred by a large target individual. While target individuals of the largest of our test species, Centaurea jacea L., had a strong impact on neighbouring species, in general, target species size was a weak predictor of the number of other resident species growing within its immediate neighbourhood, as well as the number of resident species that were reproductive. Thus, the presence of a large competitor did not restrict the ability of neighbouring species to reproduce. Lastly, target species size did not have any impact on the species size structure of neighbouring species; i.e. they did not restrict smaller, supposedly poorer competitors, from growing and reproducing close by. Taken together, these results provide no support for a size-advantage in competition restricting local species richness or the ability of small species to coexist and successfully reproduce in the immediate neighbourhood of a large species.

Community structure informs species geographic distributions

KAUST Repository

Montesinos-Navarro, Alicia

2018-05-23

Understanding what determines species\\' geographic distributions is crucial for assessing global change threats to biodiversity. Measuring limits on distributions is usually, and necessarily, done with data at large geographic extents and coarse spatial resolution. However, survival of individuals is determined by processes that happen at small spatial scales. The relative abundance of coexisting species (i.e. \\'community structure\\') reflects assembly processes occurring at small scales, and are often available for relatively extensive areas, so could be useful for explaining species distributions. We demonstrate that Bayesian Network Inference (BNI) can overcome several challenges to including community structure into studies of species distributions, despite having been little used to date. We hypothesized that the relative abundance of coexisting species can improve predictions of species distributions. In 1570 assemblages of 68 Mediterranean woody plant species we used BNI to incorporate community structure into Species Distribution Models (SDMs), alongside environmental information. Information on species associations improved SDM predictions of community structure and species distributions moderately, though for some habitat specialists the deviance explained increased by up to 15%. We demonstrate that most species associations (95%) were positive and occurred between species with ecologically similar traits. This suggests that SDM improvement could be because species co-occurrences are a proxy for local ecological processes. Our study shows that Bayesian Networks, when interpreted carefully, can be used to include local conditions into measurements of species\\' large-scale distributions, and this information can improve the predictions of species distributions.

Introduced species as evolutionary traps

Science.gov (United States)

Schlaepfer, Martin A.; Sherman, P.W.; Blossey, B.; Runge, M.C.

2005-01-01

Invasive species can alter environments in such a way that normal behavioural decision-making rules of native species are no longer adaptive. The evolutionary trap concept provides a useful framework for predicting and managing the impact of harmful invasive species. We discuss how native species can respond to changes in their selective regime via evolution or learning. We also propose novel management strategies to promote the long-term co-existence of native and introduced species in cases where the eradication of the latter is either economically or biologically unrealistic.

Why some plant species are rare.

Science.gov (United States)

Wieger Wamelink, G W; Wamelink, G W Weiger; Goedhart, Paul W; Frissel, Joep; Frissel, Josep Y

2014-01-01

Biodiversity, including plant species diversity, is threatened worldwide as a result of anthropogenic pressures such as an increase of pollutants and climate change. Rare species in particular are on the verge of becoming extinct. It is still unclear as to why some plant species are rare and others are not. Are they rare due to: intrinsic reasons, dispersal capacity, the effects of management or abiotic circumstances? Habitat preference of rare plant species may play an important role in determining why some species are rare. Based on an extensive data set of soil parameters we investigated if rarity is due to a narrow habitat preference for abiotic soil parameters. For 23 different abiotic soil parameters, of which the most influential were groundwater-table, soil-pH and nutrient-contents, we estimated species responses for common and rare species. Based on the responses per species we calculated the range of occurrence, the range between the 5 and 95 percentile of the response curve giving the habitat preference. Subsequently, we calculated the average response range for common and rare species. In addition, we designed a new graphic in order to provide a better means for presentation of the results. The habitat preferences of rare species for abiotic soil conditions are significantly narrower than for common species. Twenty of the twenty-three abiotic parameters showed on average significantly narrower habitat preferences for rare species than for common species; none of the abiotic parameters showed on average a narrower habitat preference for common species. The results have major implications for the conservation of rare plant species; accordingly management and nature development should be focussed on the maintenance and creation of a broad range of environmental conditions, so that the requirements of rare species are met. The conservation of (abiotic) gradients within ecosystems is particularly important for preserving rare species.

Species associations in a species-rich subtropical forest were not well-explained by stochastic geometry of biodiversity.

Science.gov (United States)

Wang, Qinggang; Bao, Dachuan; Guo, Yili; Lu, Junmeng; Lu, Zhijun; Xu, Yaozhan; Zhang, Kuihan; Liu, Haibo; Meng, Hongjie; Jiang, Mingxi; Qiao, Xiujuan; Huang, Handong

2014-01-01

The stochastic dilution hypothesis has been proposed to explain species coexistence in species-rich communities. The relative importance of the stochastic dilution effects with respect to other effects such as competition and habitat filtering required to be tested. In this study, using data from a 25-ha species-rich subtropical forest plot with a strong topographic structure at Badagongshan in central China, we analyzed overall species associations and fine-scale species interactions between 2,550 species pairs. The result showed that: (1) the proportion of segregation in overall species association analysis at 2 m neighborhood in this plot followed the prediction of the stochastic dilution hypothesis that segregations should decrease with species richness but that at 10 m neighborhood was higher than the prediction. (2) The proportion of no association type was lower than the expectation of stochastic dilution hypothesis. (3) Fine-scale species interaction analyses using Heterogeneous Poisson processes as null models revealed a high proportion (47%) of significant species effects. However, the assumption of separation of scale of this method was not fully met in this plot with a strong fine-scale topographic structure. We also found that for species within the same families, fine-scale positive species interactions occurred more frequently and negative ones occurred less frequently than expected by chance. These results suggested effects of environmental filtering other than species interaction in this forest. (4) We also found that arbor species showed a much higher proportion of significant fine-scale species interactions (66%) than shrub species (18%). We concluded that the stochastic dilution hypothesis only be partly supported and environmental filtering left discernible spatial signals in the spatial associations between species in this species-rich subtropical forest with a strong topographic structure.

Species associations in a species-rich subtropical forest were not well-explained by stochastic geometry of biodiversity.

Directory of Open Access Journals (Sweden)

Qinggang Wang

Full Text Available The stochastic dilution hypothesis has been proposed to explain species coexistence in species-rich communities. The relative importance of the stochastic dilution effects with respect to other effects such as competition and habitat filtering required to be tested. In this study, using data from a 25-ha species-rich subtropical forest plot with a strong topographic structure at Badagongshan in central China, we analyzed overall species associations and fine-scale species interactions between 2,550 species pairs. The result showed that: (1 the proportion of segregation in overall species association analysis at 2 m neighborhood in this plot followed the prediction of the stochastic dilution hypothesis that segregations should decrease with species richness but that at 10 m neighborhood was higher than the prediction. (2 The proportion of no association type was lower than the expectation of stochastic dilution hypothesis. (3 Fine-scale species interaction analyses using Heterogeneous Poisson processes as null models revealed a high proportion (47% of significant species effects. However, the assumption of separation of scale of this method was not fully met in this plot with a strong fine-scale topographic structure. We also found that for species within the same families, fine-scale positive species interactions occurred more frequently and negative ones occurred less frequently than expected by chance. These results suggested effects of environmental filtering other than species interaction in this forest. (4 We also found that arbor species showed a much higher proportion of significant fine-scale species interactions (66% than shrub species (18%. We concluded that the stochastic dilution hypothesis only be partly supported and environmental filtering left discernible spatial signals in the spatial associations between species in this species-rich subtropical forest with a strong topographic structure.

(Chlorophyta) biomass production using Moringa oleifera Lam. leaf ...

African Journals Online (AJOL)

Chlorella sorokiniana Shih. et Krauss, a unicellular green alga was assayed to assess its to promotion potentials response of aqueous and ethanolic leaf extracts of Moringa oleifera Lam. C. sorokiniana grown in 200 ml aliquots of modified basal medium for two weeks: was treated with the aqueous and ethanolic extracts at ...

Cross-species amplification of 105 Lolium perenne SSR loci in 23 species within the Poaceae

DEFF Research Database (Denmark)

Jensen, Louise Bach; Holm, Preben Bach; Lübberstedt, Thomas

2007-01-01

Amplification of 105 Lolium perenne SSR markers was studied in 23 grass species representing seven tribes from three subfamilies of Poaceae. Twelve of the SSR markers are published for the first time. Between 2% and 96% of the SSR markers could be amplified within a given species. A subset of eight...... SSR markers was evaluated for polymorphism across nine of the 23 grass species. Four to seven of the markers were polymorphic within each species, with an average detection of 2.4 alleles per species....

New species of Moenkhausia Eigenmann, 1903 (Characiformes: Characidae with comments on the Moenkhausia oligolepis species complex

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Ricardo C. Benine

Full Text Available A new species of Moenkhausia is described from tributaries of the rio Paraguay, Brazil. The new species is diagnosed from congeners by characters related to body coloration, the number of lateral line scales, the degree of poring of the lateral line, and number of scales rows above and below the lateral line. Molecular analyses using partial sequences of the mitochondrial gene Cytochrome Oxidase I from specimens of the new species and specimens belonging to morphologically similar species demonstrated that the new species is easily differentiated by their high genetic distance and by their position in the phylogenetic hypothesis obtained through the Maximum Parsimony methodology. The analyses of three samples of M. oligolepis also revealed that they have high genetic distances and belong to different monophyletic groups suggesting that this species corresponds to a species complex rather than a single species.

Previously unknown species of Aspergillus.

Science.gov (United States)

Gautier, M; Normand, A-C; Ranque, S

2016-08-01

The use of multi-locus DNA sequence analysis has led to the description of previously unknown 'cryptic' Aspergillus species, whereas classical morphology-based identification of Aspergillus remains limited to the section or species-complex level. The current literature highlights two main features concerning these 'cryptic' Aspergillus species. First, the prevalence of such species in clinical samples is relatively high compared with emergent filamentous fungal taxa such as Mucorales, Scedosporium or Fusarium. Second, it is clearly important to identify these species in the clinical laboratory because of the high frequency of antifungal drug-resistant isolates of such Aspergillus species. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been shown to enable the identification of filamentous fungi with an accuracy similar to that of DNA sequence-based methods. As MALDI-TOF MS is well suited to the routine clinical laboratory workflow, it facilitates the identification of these 'cryptic' Aspergillus species at the routine mycology bench. The rapid establishment of enhanced filamentous fungi identification facilities will lead to a better understanding of the epidemiology and clinical importance of these emerging Aspergillus species. Based on routine MALDI-TOF MS-based identification results, we provide original insights into the key interpretation issues of a positive Aspergillus culture from a clinical sample. Which ubiquitous species that are frequently isolated from air samples are rarely involved in human invasive disease? Can both the species and the type of biological sample indicate Aspergillus carriage, colonization or infection in a patient? Highly accurate routine filamentous fungi identification is central to enhance the understanding of these previously unknown Aspergillus species, with a vital impact on further improved patient care. Copyright © 2016 European Society of Clinical Microbiology and

Revision of the western Palaearctic species of Aleiodes Wesmael (Hymenoptera, Braconidae, Rogadinae. Part 1: Introduction, key to species groups, outlying distinctive species, and revisionary notes on some further species

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Cornelis van Achterberg

2016-12-01

Full Text Available Seven new species of the genus Aleiodes Wesmael, 1838 (Braconidae: Rogadinae are described and illustrated: A. abraxanae sp. n., A. angustipterus sp. n., A. artesiariae sp. n., A. carminatus sp. n., A. diarsianae sp. n., A. leptofemur sp. n., and A. ryrholmi sp. n. A neotype is designated for each of Aleiodes circumscriptus (Nees, 1834 and A. pictus (Herrich-Schäffer, 1838, and both species are redescribed and illustrated. Aleiodes ochraceus Hellén, 1927 (not A. ochraceus (Curtis, 1834 is renamed as A. curticornis nom. n. & stat. rev., and redescribed and illustrated. Aleiodes bistrigatus Roman, 1917, A. nigriceps Wesmael, 1838, and A. reticulatus (Noskiewicz, 1956, are re-instated as valid species. A lectotype is designated for Aleiodes bistrigatus Roman. An illustrated key is given to some distinctive species and the residual species groups along which further parts of an entire revision of western Palaearctic species of Aleiodes and Heterogamus will be organised. Biology, host associations and phenology are discussed for the keyed species (in addition to the above, A. albitibia (Herrich-Schäffer, 1838, A. apiculatus (Fahringer, 1932, A. arcticus (Thomson, 1892, A. cantherius (Lyle, 1919, A. esenbeckii (Hartig, 1834, A. jakowlewi (Kokujev, 1898, A. modestus (Reinhard, 1863, A. nigricornis Wesmael, 1838, A. pallidator (Thunberg, 1822, A. praetor (Reinhard, 1863, A. seriatus (Herrich- Schäffer, 1838 sensu lato, A. testaceus (Telenga, 1941, A. ungularis (Thomson, 1892, and A. varius (Herrich-Schäffer, 1838 which are dealt with in full here (with the exception of A. seriatus s.l. which is, however, included in the key. The experimental methodology covering the revision as a whole, which involves some behavioural investigation, is outlined.

Species coextinctions and the biodiversity crisis.

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Koh, Lian Pin; Dunn, Robert R; Sodhi, Navjot S; Colwell, Robert K; Proctor, Heather C; Smith, Vincent S

2004-09-10

To assess the coextinction of species (the loss of a species upon the loss of another), we present a probabilistic model, scaled with empirical data. The model examines the relationship between coextinction levels (proportion of species extinct) of affiliates and their hosts across a wide range of coevolved interspecific systems: pollinating Ficus wasps and Ficus, parasites and their hosts, butterflies and their larval host plants, and ant butterflies and their host ants. Applying a nomographic method based on mean host specificity (number of host species per affiliate species), we estimate that 6300 affiliate species are "coendangered" with host species currently listed as endangered. Current extinction estimates need to be recalibrated by taking species coextinctions into account.

Reproductive Impacts of Endocrine-Disrupting Chemicals on Wildlife Species: Implications for Conservation of Endangered Species.

Science.gov (United States)

Tubbs, Christopher W; McDonough, Caitlin E

2018-02-15

Wildlife have proven valuable to our understanding of the potential effects of endocrine-disrupting chemicals (EDCs) on human health by contributing considerably to our understanding of the mechanisms and consequences of EDC exposure. But the threats EDCs present to populations of wildlife species themselves are significant, particularly for endangered species whose existence is vulnerable to any reproductive perturbation. However, few studies address the threats EDCs pose to endangered species owing to challenges associated with their study. Here, we highlight those barriers and review the available literature concerning EDC effects on endangered species. Drawing from other investigations into nonthreatened wildlife species, we highlight opportunities for new approaches to advance our understanding and potentially mitigate the effects of EDCs on endangered species to enhance their fertility.

Ecological impacts of non-native species

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Wilkinson, John W.

2012-01-01

Non-native species are considered one of the greatest threats to freshwater biodiversity worldwide (Drake et al. 1989; Allen and Flecker 1993; Dudgeon et al. 2005). Some of the first hypotheses proposed to explain global patterns of amphibian declines included the effects of non-native species (Barinaga 1990; Blaustein and Wake 1990; Wake and Morowitz 1991). Evidence for the impact of non-native species on amphibians stems (1) from correlative research that relates the distribution or abundance of a species to that of a putative non-native species, and (2) from experimental tests of the effects of a non-native species on survival, growth, development or behaviour of a target species (Kats and Ferrer 2003). Over the past two decades, research on the effects of non-native species on amphibians has mostly focused on introduced aquatic predators, particularly fish. Recent research has shifted to more complex ecological relationships such as influences of sub-lethal stressors (e.g. contaminants) on the effects of non-native species (Linder et al. 2003; Sih et al. 2004), non-native species as vectors of disease (Daszak et al. 2004; Garner et al. 2006), hybridization between non-natives and native congeners (Riley et al. 2003; Storfer et al. 2004), and the alteration of food-webs by non-native species (Nystrom et al. 2001). Other research has examined the interaction of non-native species in terms of facilitation (i.e. one non-native enabling another to become established or spread) or the synergistic effects of multiple non-native species on native amphibians, the so-called invasional meltdown hypothesis (Simerloff and Von Holle 1999). Although there is evidence that some non-native species may interact (Ricciardi 2001), there has yet to be convincing evidence that such interactions have led to an accelerated increase in the number of non-native species and cumulative impacts are still uncertain (Simberloff 2006). Applied research on the control, eradication, and

Seasonal species interactions minimize the impact of species turnover on the likelihood of community persistence.

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Saavedra, Serguei; Rohr, Rudolf P; Fortuna, Miguel A; Selva, Nuria; Bascompte, Jordi

2016-04-01

Many of the observed species interactions embedded in ecological communities are not permanent, but are characterized by temporal changes that are observed along with abiotic and biotic variations. While work has been done describing and quantifying these changes, little is known about their consequences for species coexistence. Here, we investigate the extent to which changes of species composition impact the likelihood of persistence of the predator-prey community in the highly seasonal Białowieza Primeval Forest (northeast Poland), and the extent to which seasonal changes of species interactions (predator diet) modulate the expected impact. This likelihood is estimated extending recent developments on the study of structural stability in ecological communities. We find that the observed species turnover strongly varies the likelihood of community persistence between summer and winter. Importantly, we demonstrate that the observed seasonal interaction changes minimize the variation in the likelihood of persistence associated with species turnover across the year. We find that these community dynamics can be explained as the coupling of individual species to their environment by minimizing both the variation in persistence conditions and the interaction changes between seasons. Our results provide a homeostatic explanation for seasonal species interactions and suggest that monitoring the association of interactions changes with the level of variation in community dynamics can provide a good indicator of the response of species to environmental pressures.

Two new species of nocturnal bees of the genus Megalopta (Hymenoptera: Halictidae) with keys to species.

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Gonzalez, Victor H; Griswold, Terry; Ayala, Ricardo

2010-03-01

Megalopta Smith, 1853, is a Neotropical genus of nocturnal or crepuscular bees. Two subgenera are recognized with most of its nearly 30 species placed in the nominate subgenus. Species of Megalopta s. str. are more commonly collected than species of Noctoraptor Engel et al. 1997, all presumably parasites of Megalopta s. str. Two new species of Megalopta are described here: M. (Megalopta) tetewana, n. sp., from Mexico and M. (Noctoraptor) huaoranii, n. sp., from Ecuador. Identification keys to the Central American species of Megalopta s. str. and the species of the parasitic subgenus Noctoraptor are presented.

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.

A new species of Labidocera (Copepoda, Calanoida, Pontellidae) collected from Okinawa, southwestern Japan, with establishment of five Indo-West Pacific species groups in the L.detruncata species complex.

Science.gov (United States)

Hirabayashi, Takeshi; Ohtsuka, Susumu

2014-01-01

Labidocerachuraumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the Labidoceramadurae species group, within the Labidoceradetruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo) and defined on the basis of difference in sexual dimorphism.

Quantifying the invasiveness of species

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Robert Colautti

2014-04-01

Full Text Available The success of invasive species has been explained by two contrasting but non-exclusive views: (i intrinsic factors make some species inherently good invaders; (ii species become invasive as a result of extrinsic ecological and genetic influences such as release from natural enemies, hybridization or other novel ecological and evolutionary interactions. These viewpoints are rarely distinguished but hinge on distinct mechanisms leading to different management scenarios. To improve tests of these hypotheses of invasion success we introduce a simple mathematical framework to quantify the invasiveness of species along two axes: (i interspecific differences in performance among native and introduced species within a region, and (ii intraspecific differences between populations of a species in its native and introduced ranges. Applying these equations to a sample dataset of occurrences of 1,416 plant species across Europe, Argentina, and South Africa, we found that many species are common in their native range but become rare following introduction; only a few introduced species become more common. Biogeographical factors limiting spread (e.g. biotic resistance, time of invasion therefore appear more common than those promoting invasion (e.g. enemy release. Invasiveness, as measured by occurrence data, is better explained by inter-specific variation in invasion potential than biogeographical changes in performance. We discuss how applying these comparisons to more detailed performance data would improve hypothesis testing in invasion biology and potentially lead to more efficient management strategies.

Dna c-values of 20 invasive alien species and 3 native species in south china

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Gong Ni

2014-01-01

Full Text Available Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lowest DNA C-value among the perennials, indicating that native species with low nuclear content may also possess an invasive potential.

From single-species advice to mixed-species management: taking the next step

DEFF Research Database (Denmark)

Vinther, Morten; Reeves, S.A.; Patterson, K.R.

2004-01-01

Fishery management advice has traditionally been given on a stock-by-stock basis. Recent problems in implementing this advice, particularly for the demersal fisheries of the North Sea, have highlighted the limitations of the approach. In the long term, it would be desirable to give advice...... that accounts for mixed-fishery effects, but in the short term there is a need for approaches to resolve the conflicting management advice for different species within the same fishery, and to generate catch or effort advice that accounts for the mixed-species nature of the fishery. This paper documents...... a recent approach used to address these problems. The approach takes the single-species advice for each species in the fishery as a starting point, then attempts to resolve it into consistent catch or effort advice using fleet-disaggregated catch forecasts in combination with explicitly stated management...

An analysis of species boundaries and biogeographic patterns in a cryptic species complex: the rotifer--Brachionus plicatilis.

Science.gov (United States)

Suatoni, Elizabeth; Vicario, Saverio; Rice, Sean; Snell, Terry; Caccone, Adalgisa

2006-10-01

Since the advent of molecular phylogenetics, there is increasing evidence that many small aquatic and marine invertebrates--once believed to be single, cosmopolitan species--are in fact cryptic species complexes. Although the application of the biological species concept is central to the identification of species boundaries in these cryptic complexes, tests of reproductive isolation do not frequently accompany phylogenetic studies. Because different species concepts generally identify different boundaries in cryptic complexes, studies that apply multiple species concepts are needed to gain a more detailed understanding of patterns of diversification in these taxa. Here we explore different methods of empirically delimiting species boundaries in the salt water rotifer Brachionus plicatilis by comparing reproductive data (i.e., the traditional biological species concept) to phylogenetic data (the genealogical species concept). Based on a high degree of molecular sequence divergence and largely concordant genetic patterns in COI and ITS1, the genealogical species hypothesis indicates the existence of at least 14 species--the highest estimate for the group thus far. A test of the genealogical species concept with biological crosses shows a fairly high level of concordance, depending on the degree of reproductive success used to draw boundaries. The convergence of species concepts in this group suggests that many of the species within the group may be old. Although the diversity of the group is higher than previously understood, geographic distributions remain broad. Efficient passive dispersal has resulted in global distributions for many species with some evidence of isolation by distance over large geographic scales. These patterns concur with expectations that micro-meiofauna (0.1-1mm) have biogeographies intermediate to microbial organisms and large vertebrates. Sympatry of genetically distant strains is common.

Effects of species' characteristics on nongovernmental organizations' attitudes toward species conservation policy

NARCIS (Netherlands)

Knegtering, E; Hendrickx, L.C W P; van der Windt, H.J.; Schoot Uiterkamp, A.J.M.

The authors examined the willingness of nongovernmental organizations (NGOs) to support public species conservation measures as a function of species characteristics, NGOs' interests, and interests harmed by the measures. In an experiment, 39 policy makers from nature conservation, mobility and

Neosilba (Tephritoidea: Lonchaeidae) species reared from coffee in Brazil, with description of a new species

Energy Technology Data Exchange (ETDEWEB)

Striki, Pedro Carlos; Prado, Angelo Pires do, E-mail: apprado@unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Biologia. Dept. de Parasitologia

2006-07-01

Neosilba species are believed to be secondary invaders of fruit, so, little attention has been paid to its presence in coffee fruits. In this article we present a key to Neosilba species present in coffee fruits and describe a new species that is considered a primary invader. We hope this will help researchers working with coffee fruits to better quantify the economic importance of Neosilba species associated with coffee fruits. (author)

Neosilba (Tephritoidea: Lonchaeidae) species reared from coffee in Brazil, with description of a new species

International Nuclear Information System (INIS)

Striki, Pedro Carlos; Prado, Angelo Pires do

2006-01-01

Neosilba species are believed to be secondary invaders of fruit, so, little attention has been paid to its presence in coffee fruits. In this article we present a key to Neosilba species present in coffee fruits and describe a new species that is considered a primary invader. We hope this will help researchers working with coffee fruits to better quantify the economic importance of Neosilba species associated with coffee fruits. (author)

Evaluating Hypotheses of Plant Species Invasions on Mediterranean Islands: Inverse Patterns between Alien and Endemic Species

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Alexander Bjarnason

2017-08-01

Full Text Available Invasive alien species cause major changes to ecosystem functioning and patterns of biodiversity, and the main factors involved in invasion success remain contested. Using the Mediterranean island of Crete, Greece as a case study, we suggest a framework for analyzing spatial data of alien species distributions, based on environmental predictors, aiming to gain an understanding of their spatial patterns and spread. Mediterranean islands are under strong ecological pressure from invading species due to their restricted size and increased human impact. Four hypotheses of invasibility, the “propagule pressure hypothesis” (H1, “biotic resistance hypothesis vs. acceptance hypothesis” (H2, “disturbance-mediated hypothesis” (H3, and “environmental heterogeneity hypothesis” (H4 were tested. Using data from alien, native, and endemic vascular plant species, the propagule pressure, biotic resistance vs. acceptance, disturbance-mediated, and environmental heterogeneity hypotheses were tested with Generalized Additive Modeling (GAM of 39 models. Based on model selection, the optimal model includes the positive covariates of native species richness, the negative covariates of endemic species richness, and land area. Variance partitioning between the four hypotheses indicated that the biotic resistance vs. acceptance hypothesis explained the vast majority of the total variance. These results show that areas of high species richness have greater invasibility and support the acceptance hypothesis and “rich-get-richer” distribution of alien species. The negative correlation between alien and endemic species appears to be predominantly driven by altitude, with fewer alien and more endemic species at greater altitudes, and habitat richness. The negative relationship between alien and endemic species richness provides potential for understanding patterns of endemic and alien species on islands, contributing to more effective conservation

Construction of analytically solvable models for interacting species. [biological species competition

Science.gov (United States)

Rosen, G.

1976-01-01

The basic form of a model representation for systems of n interacting biological species is a set of essentially nonlinear autonomous ordinary differential equations. A generic canonical expression for the rate functions in the equations is reported which permits the analytical general solution to be obtained by elementary computation. It is shown that a general analytical solution is directly obtainable for models where the rate functions are prescribed by the generic canonical expression from the outset. Some illustrative examples are given which demonstrate that the generic canonical expression can be used to construct analytically solvable models for two interacting species with limit-cycle dynamics as well as for a three-species interdependence.

A new species of Labidocera (Copepoda, Calanoida, Pontellidae collected from Okinawa, southwestern Japan, with establishment of five Indo-West Pacific species groups in the L. detruncata species complex

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Takeshi Hirabayashi

2014-10-01

Full Text Available Labidocera churaumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the L. madurae species group, within the L. detruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo and defined on the basis of difference in sexual dimorphism.

A new species of Labidocera (Copepoda, Calanoida, Pontellidae) collected from Okinawa, southwestern Japan, with establishment of five Indo-West Pacific species groups in the L. detruncata species complex

Science.gov (United States)

Hirabayashi, Takeshi; Ohtsuka, Susumu

2014-01-01

Abstract Labidocera churaumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the Labidocera madurae species group, within the Labidocera detruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo) and defined on the basis of difference in sexual dimorphism. PMID:25349514

Basicladia chelonum (Collins W.E. Hoffmann et Tilden (Chlorophyta, Cladophorophyceae from Cuba (Caribbean: new observation of the ultrastructure of its vegetative cells

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Joanna Czerwik-Marcinkowska

2011-01-01

Full Text Available Basicladia chelonum (Collins W.E. Hoffmann and Tilden (1930 principally known from North America and Hawaii was recently (2004 found in Cuba (Caribbean from artificial pool growing on shells of musk turtles (Trachemys decussata Gray. Specimens collected in Cuba were subjected to detailed examinations also using a transmission electron microscope. On one hand, these studies confirmed many features of this species previously described by earlier authors in the specimens from Texas. On the other hand, the present studies revealed structures unknown so far (pyrenoid structure, which allowed for new analysis of this species. These investigations also have shown that Basicladia chelonum exhibits close similarity to the genus Cladophora and other representatives of the class Cladophorophyceae. The similarities include : siphonocladous level of organization of thallus, numerous chloroplasts forming a network and other structures. Conversely, the pyrenoid in vegetative cells of Basicladia chelonum distinguishes it markedly from representatives of the genus Cladophora, which have bilenticular pyrenoids divided into two hemispheres by a single thylakoids and each hemisphere is covered by a bowlshaped starch grain (Van Hoek et al. 1995. Since in Cladophora the ultrastructure of the pyrenoid is highly constant and characteristic, this contrasts with the genus Basicladia and, therefore, more firmly establishes position of the latter as an independent unit within Cladophorophyceae.

Comparison of species ordinations resulting from alternative indices of interspecific association and different numbers of included species

Energy Technology Data Exchange (ETDEWEB)

Goff, F G

1975-12-19

Several measures of interspecific association are compared. Dispersion and covariance are limited in value because they respond to the commonness of the species compared. Correlation is not so limited but it responds to discrepancies in commonness among the species. The practical result of these relationships between commonness and association is that only the most common species can occupy peripheral positions in a species ordination. Rare species are relegated to positions near the center not on the basis of their phytosociological pattern but simply because of their rarity. Both Cole's index of association and the tetrachoric correlation overcome the problem imposed by the relationship between ordination position and species commonness and they both produce very similar results. The effect of differing numbers of species on the ordination configuration is examined using both Pearson's correlation and Cole's index. The basic pattern of the ordination is set with the first few species when Cole's index is used, however, since rare species are given more weight in the analysis with this index, the addition of several very rare species can change the configuration of the ordination. (auth)

CpDNA-based species identification and phylogeography: application to African tropical tree species.

Science.gov (United States)

Duminil, J; Heuertz, M; Doucet, J-L; Bourland, N; Cruaud, C; Gavory, F; Doumenge, C; Navascués, M; Hardy, O J

2010-12-01

Despite the importance of the African tropical rainforests as a hotspot of biodiversity, their history and the processes that have structured their biodiversity are understood poorly. With respect to past demographic processes, new insights can be gained through characterizing the distribution of genetic diversity. However, few studies of this type have been conducted in Central Africa, where the identification of species in the field can be difficult. We examine here the distribution of chloroplast DNA (cpDNA) diversity in Lower Guinea in two tree species that are difficult to distinguish, Erythrophleum ivorense and Erythrophleum suaveolens (Fabaceae). By using a blind-sampling approach and comparing molecular and morphological markers, we first identified retrospectively all sampled individuals and determined the limits of the distribution of each species. We then performed a phylogeographic study using the same genetic data set. The two species displayed essentially parapatric distributions that were correlated well with the rainfall gradient, which indicated different ecological requirements. In addition, a phylogeographic structure was found for E. suaveolens and, for both species, substantially higher levels of diversity and allelic endemism were observed in the south (Gabon) than in the north (Cameroon) of the Lower Guinea region. This finding indicated different histories of population demographics for the two species, which might reflect different responses to Quaternary climate changes. We suggest that a recent period of forest perturbation, which might have been caused by humans, favoured the spread of these two species and that their poor recruitment at present results from natural succession in their forest formations. © 2010 Blackwell Publishing Ltd.

Endangered Species Protection Bulletins

Science.gov (United States)

Endangered Species Protection Bulletins set forth geographically specific pesticide use limitations for the protection of threatened and endangered (listed) species and their designated critical habitat. Find out how to get and use Bulletins.

New Malesian species of Viscaceae

NARCIS (Netherlands)

Barlow, Bryan A.

1996-01-01

Three new Malesian species of Viscaceae are described. Ginalloa flagellaris Barlow is distinguished as a species from New Guinea and New Britain, previously included within G. arnottiana Korthals. Viscum exile Barlow is recognized as a new species endemic to Celebes, related to V. ovalifolium.

Toward reassessing data-deficient species.

Science.gov (United States)

Bland, Lucie M; Bielby, Jon; Kearney, Stephen; Orme, C David L; Watson, James E M; Collen, Ben

2017-06-01

One in 6 species (13,465 species) on the International Union for Conservation of Nature (IUCN) Red List is classified as data deficient due to lack of information on their taxonomy, population status, or impact of threats. Despite the chance that many are at high risk of extinction, data-deficient species are typically excluded from global and local conservation priorities, as well as funding schemes. The number of data-deficient species will greatly increase as the IUCN Red List becomes more inclusive of poorly known and speciose groups. A strategic approach is urgently needed to enhance the conservation value of data-deficient assessments. To develop this, we reviewed 2879 data-deficient assessments in 6 animal groups and identified 8 main justifications for assigning data-deficient status (type series, few records, old records, uncertain provenance, uncertain population status or distribution, uncertain threats, taxonomic uncertainty, and new species). Assigning a consistent set of justification tags (i.e., consistent assignment to assessment justifications) to species classified as data deficient is a simple way to achieve more strategic assessments. Such tags would clarify the causes of data deficiency; facilitate the prediction of extinction risk; facilitate comparisons of data deficiency among taxonomic groups; and help prioritize species for reassessment. With renewed efforts, it could be straightforward to prevent thousands of data-deficient species slipping unnoticed toward extinction. © 2016 Society for Conservation Biology.

Are trade-offs among species' ecological interactions scale dependent? A test using pitcher-plant inquiline species.

Science.gov (United States)

Kneitel, Jamie M

2012-01-01

Trade-offs among species' ecological interactions is a pervasive explanation for species coexistence. The traits associated with trade-offs are typically measured to mechanistically explain species coexistence at a single spatial scale. However, species potentially interact at multiple scales and this may be reflected in the traits among coexisting species. I quantified species' ecological traits associated with the trade-offs expected at both local (competitive ability and predator tolerance) and regional (competitive ability and colonization rate) community scales. The most common species (four protozoa and a rotifer) from the middle trophic level of a pitcher plant (Sarracenia purpurea) inquiline community were used to link species traits to previously observed patterns of species diversity and abundance. Traits associated with trade-offs (competitive ability, predator tolerance, and colonization rate) and other ecological traits (size, growth rate, and carrying capacity) were measured for each of the focal species. Traits were correlated with one another with a negative relationship indicative of a trade-off. Protozoan and rotifer species exhibited a negative relationship between competitive ability and predator tolerance, indicative of coexistence at the local community scale. There was no relationship between competitive ability and colonization rate. Size, growth rate, and carrying capacity were correlated with each other and the trade-off traits: Size was related to both competitive ability and predator tolerance, but growth rate and carrying capacity were correlated with predator tolerance. When partial correlations were conducted controlling for size, growth rate and carrying capacity, the trade-offs largely disappeared. These results imply that body size is the trait that provides the basis for ecological interactions and trade-offs. Altogether, this study showed that the examination of species' traits in the context of coexistence at different scales

A new Amazonian species from the Drosophila annulimana species group (Diptera, Drosophilidae

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Marco S. Gottschalk

2012-12-01

Full Text Available Drosophila caxiuana sp. nov., Drosophila subgenus, is described and illustrated. This new species was collected in the Amazonian Biome (Caquajó river, Portel, Pará, Brazil and is an atypical species to the group due the unusual morphology of the male terminalia.

75 FR 78974 - Endangered Species

Science.gov (United States)

2010-12-17

...-XA086 Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... the Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.) and the regulations governing the taking, importing, and exporting of endangered and threatened species (50 CFR 222-226). Permit...

Dna c-values of 20 invasive alien species and 3 native species in south china

OpenAIRE

Gong Ni; Wang Yu-Tao; Björn Lars Olof; Li Shao-Shan

2014-01-01

Cultivated fields and forests in South China are experiencing serious damage due to invasive alien plants. We investigated the relation between DNA C-values and invasiveness. The DNA C-values of 23 species ranged from 0.39 pg to 3.37 pg. Herbs, perennials and native species had higher mean DNA C-values than shrubs, annuals and invasive alien species. DNA C-values decreased with increasing invasiveness. Paederia scandens, a harmful native species, has the lo...

Biological species in the viral world.

Science.gov (United States)

Bobay, Louis-Marie; Ochman, Howard

2018-06-05

Due to their dependence on cellular organisms for metabolism and replication, viruses are typically named and assigned to species according to their genome structure and the original host that they infect. But because viruses often infect multiple hosts and the numbers of distinct lineages within a host can be vast, their delineation into species is often dictated by arbitrary sequence thresholds, which are highly inconsistent across lineages. Here we apply an approach to determine the boundaries of viral species based on the detection of gene flow within populations, thereby defining viral species according to the biological species concept (BSC). Despite the potential for gene transfer between highly divergent genomes, viruses, like the cellular organisms they infect, assort into reproductively isolated groups and can be organized into biological species. This approach revealed that BSC-defined viral species are often congruent with the taxonomic partitioning based on shared gene contents and host tropism, and that bacteriophages can similarly be classified in biological species. These results open the possibility to use a single, universal definition of species that is applicable across cellular and acellular lifeforms.

Cryptic Species Due to Hybridization: A Combined Approach to Describe a New Species (Carex: Cyperaceae).

Science.gov (United States)

Maguilla, Enrique; Escudero, Marcial

2016-01-01

Disappearance of diagnostic morphological characters due to hybridization is considered to be one of the causes of the complex taxonomy of the species-rich (ca. 2000 described species) genus Carex (Cyperaceae). Carex furva s.l. belongs to section Glareosae. It is an endemic species from the high mountains of the Iberian Peninsula (Spain and Portugal). Previous studies suggested the existence of two different, cryptic taxa within C. furva s.l. Intermediate morphologies found in the southern Iberian Peninsula precluded the description of a new taxa. We aimed to determine whether C. furva s.l. should be split into two different species based on the combination of morphological and molecular data. We sampled ten populations across its full range and performed a morphological study based on measurements on herbarium specimens and silica-dried inflorescences. Both morphological and phylogenetic data support the existence of two different species within C. furva s.l. Nevertheless, intermediate morphologies and sterile specimens were found in one of the southern populations (Sierra Nevada) of C. furva s.l., suggesting the presence of hybrid populations in areas where both supposed species coexist. Hybridization between these two putative species has blurred morphological and genetic limits among them in this hybrid zone. We have proved the utility of combining molecular and morphological data to discover a new cryptic species in a scenario of hybridization. We now recognize a new species, C. lucennoiberica, endemic to the Iberian Peninsula (Sierra Nevada, Central system and Cantabrian Mountains). On the other hand, C. furva s.s. is distributed only in Sierra Nevada, where it may be threatened by hybridization with C. lucennoiberica. The restricted distribution of both species and their specific habitat requirements are the main limiting factors for their conservation.

Leadership of Winter Mixed-Species Flocks by Tufted Titmice (Baeolophus bicolor: Are Titmice Passive Nuclear Species?

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Thomas A. Contreras

2011-01-01

Full Text Available The tufted titmouse (Baeolophus bicolor, TUTI is a nuclear species in winter foraging flocks whose antipredator calls are used to manage predation risk by diverse heterospecifics. We hypothesized that satellite species in mixed flocks follow TUTI (not vice versa, thereby defining the role of TUTI as a “passive” nuclear species. We followed 20 winter mixed-species flocks in North-Central Florida and assessed angular-angular correlations between overall flock, TUTI, and satellite species movement directions. We observed significant correlations between overall flock movement directions and those of TUTI, confirming our central prediction. Within flocks, however, fine-scale movement directions of satellite species were often more highly correlated with those of other satellites than with TUTI movements. We conclude that TUTI are passive nuclear species whose movements define flock paths, but within flocks, TUTI movements may have less influence on satellite movements than do other factors.

Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding.

Science.gov (United States)

Ghahramanzadeh, R; Esselink, G; Kodde, L P; Duistermaat, H; van Valkenburg, J L C H; Marashi, S H; Smulders, M J M; van de Wiel, C C M

2013-01-01

Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to prevent them from entering a country. However, many related species are commercially traded, and distinguishing invasive from non-invasive species based on morphology alone is often difficult for plants in a vegetative stage. In this regard, DNA barcoding could become a good alternative. In this study, 242 samples belonging to 26 species from 10 genera of aquatic plants were assessed using the chloroplast loci trnH-psbA, matK and rbcL. Despite testing a large number of primer sets and several PCR protocols, the matK locus could not be amplified or sequenced reliably and therefore was left out of the analysis. Using the other two loci, eight invasive species could be distinguished from their respective related species, a ninth one failed to produce sequences of sufficient quality. Based on the criteria of universal application, high sequence divergence and level of species discrimination, the trnH-psbA noncoding spacer was the best performing barcode in the aquatic plant species studied. Thus, DNA barcoding may be helpful with enforcing a ban on trade of such invasive species, such as is already in place in the Netherlands. This will become even more so once DNA barcoding would be turned into machinery routinely operable by a nonspecialist in botany and molecular genetics. © 2012 Blackwell Publishing Ltd.

Usefulness of the wildlife species as a focal species in the forest ...

African Journals Online (AJOL)

yasinucarlı

2011-03-14

Mar 14, 2011 ... keystone species are the most important species in that ecosystems to sustainability. ... bear, Wolf and Eurasian Lynx can be also used as a flagship, indicator and ... Washington's Pacific coast. ... sidered keystones because their effect is not dispro- ..... conservation of South American terrestrial mammals.

76 FR 2348 - Endangered Species

Science.gov (United States)

2011-01-13

.... 15596] Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... requested permit has been issued under the authority of the Endangered Species Act of 1973, as amended (ESA... endangered and threatened species (50 CFR parts 222-226). The North Carolina Aquarium at Fort Fisher has been...

ICRAF Species Switchboard. Version 1.2

DEFF Research Database (Denmark)

Kindt, R.; Ordonez, J.; Smith, E.

2015-01-01

The current version of the Agroforestry Species Switchboard documents the presence of a total of 26,135 plant species (33,813 species including synonyms) across 19 web-based databases. When available, hyperlinks to information on the selected species in particular databases are provided. In total...

A Theory of Flagship Species Action

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Paul Jepson

2015-01-01

Full Text Available The flagship species approach is an enduring strategy in conservation. Academic discussion on flagship species has focussed on two dimensions: on what basis should they be selected and how have they been put to use. Here we consider a third dimension, namely the manner in which flagship species act and have the capacity to galvanise and influence conservation outcomes. Drawing on concepts from the social sciences, viz. affordance, framing, and actor-networks; we discuss examples of flagship species to propose a theory of flagship species action. In brief, our theory posits that a flagship species is one with traits that afford the assembly of relatively coherent networks of associations with ideational elements located in pre-existing cultural framings. These associations give rise to opportunities to align with deep cultural frames, contemporary cultural phenomena and political economy such that when a conservation action is introduced, forms of agency cause the species and human publics to change. The species becomes re-framed (or reinvigorated as a cultural asset speaking for a wider nature, publics and political agendas. Further our theory posits that species with traits that enrol in idea networks incorporating human fears, will have limited flagship capacity. This is because the ability of the representations produced to align with frames incorporating collective aspirations is constrained. In terms of applied conservation practice, our theory suggests that: a key criteria for selecting potential flagship species is presence in existing cultural frames, that effective deployment of flagship species requires an understanding of the species′ cultural associations, and a species ability to galvanise action may be limited to certain times and places. Furthermore, once deployed conservation interests will never have full control over the flagship species: it may act in uncertain and unexpected ways.

Species richness, habitable volume, and species densities in freshwater, the sea, and on land

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Michael N Dawson

2012-09-01

Full Text Available Approximately 0.5–2.0 million eukaryotic species inhabit the seas, whereas 2.0–10.0 million inhabit freshwater or the land. Much has been made of this several-fold difference in species richness but there is little consensus about the causes. Here, I ask a related question: what is the relative density of species in marine and non-marine realms? I use recent estimates of global eukaryotic species richness and published estimates of the areal coverage and depth of habitat for freshwater, marine, and terrestrial biomes. I find that the marine realm harbors ~99.83% of the habitable volume on this planet. Eukaryotic species density of the marine realm is ~3600-fold (i.e., 3-4 orders of magnitude less than that of non-marine environments. Species–volume relationships (SVRs help reconcile actinopterygian fish diversity with global primary productivity and emphasize the interacting roles of abiotic and biotic complexity in shaping patterns of biodiversity in freshwater, the sea, and on land. Comparing SVRs of habitats within and across realms may help resolve the factors and interactions that influence species density.

California Endangered Species Resource Guide.

Science.gov (United States)

California State Dept. of Education, Los Angeles.

This document was developed in response to California Senate Bill No. 885, "The Endangered Species Education Project," that called for a statewide program in which schools adopt a local endangered species, research past and current efforts to preserve the species' habitat, develop and implement an action plan to educate the community…

Biological review of 82 species of coral petitioned to be included in the Endangered Species Act

Science.gov (United States)

Brainard, Russell E.; Birkeland, Charles; Eakin, C. Mark; McElhany, Paul; Miller, Margaret W.; Patterson, Matt; Piniak, G.A.

2011-01-01

list 83 coral species as threatened or endangered under the U.S. Endangered Species Act. The petition was based on a predicted decline in available habitat for the species, citing anthropogenic climate change and ocean acidification as the lead factors among the various stressors responsible for the potential decline. The NMFS identified 82 of the corals as candidate species, finding that the petition provided substantive information for a potential listing of these species. The NMFS established a Biological Review Team (BRT) to prepare this Status Review Report that examines the status of these 82 candidate coral species and evaluates extinction risk for each of them. This document makes no recommendations for listing, as that is a separate evaluation to be conducted by the NMFS.

Emergent neutrality drives phytoplankton species coexistence

Science.gov (United States)

Segura, Angel M.; Calliari, Danilo; Kruk, Carla; Conde, Daniel; Bonilla, Sylvia; Fort, Hugo

2011-01-01

The mechanisms that drive species coexistence and community dynamics have long puzzled ecologists. Here, we explain species coexistence, size structure and diversity patterns in a phytoplankton community using a combination of four fundamental factors: organism traits, size-based constraints, hydrology and species competition. Using a ‘microscopic’ Lotka–Volterra competition (MLVC) model (i.e. with explicit recipes to compute its parameters), we provide a mechanistic explanation of species coexistence along a niche axis (i.e. organismic volume). We based our model on empirically measured quantities, minimal ecological assumptions and stochastic processes. In nature, we found aggregated patterns of species biovolume (i.e. clumps) along the volume axis and a peak in species richness. Both patterns were reproduced by the MLVC model. Observed clumps corresponded to niche zones (volumes) where species fitness was highest, or where fitness was equal among competing species. The latter implies the action of equalizing processes, which would suggest emergent neutrality as a plausible mechanism to explain community patterns. PMID:21177680

New species of Auritella (Inocybaceae) from Cameroon, with a worldwide key to the known species.

Science.gov (United States)

Matheny, P Brandon; Henkel, Terry W; Séné, Olivier; Korotkin, Hailee B; Dentinger, Bryn T M; Aime, M Catherine

2017-12-01

Two new species in the genus Auritella ( Inocybaceae ) are described as new from tropical rainforest in Cameroon. Descriptions, photographs, line drawings, and a worldwide taxonomic key to the described species of Auritella are presented. Phylogenetic analysis of 28S rDNA and rpb2 nucleotide sequence data suggests at least five phylogenetic species that can be ascribed to Auritella occur in the region comprising Cameroon and Gabon and constitute a strongly supported monophyletic subgroup within the genus. Phylogenetic analysis of ITS data supports the conspecificity of numerous collections attributed to the two new species as well as the monophyly of Australian species of Auritella . This work raises the known number of described species of Auritella to thirteen worldwide, four of which occur in tropical Africa, one in tropical India, and eight in temperate and tropical regions of Australia. This is the first study to confirm an ectomycorrhizal status of Auritella using molecular data.

Molluscan indicator species and their potential use in ecological status assessment using species distribution modeling.

Science.gov (United States)

Moraitis, Manos L; Tsikopoulou, Irini; Geropoulos, Antonios; Dimitriou, Panagiotis D; Papageorgiou, Nafsika; Giannoulaki, Marianna; Valavanis, Vasilis D; Karakassis, Ioannis

2018-05-24

Marine habitat assessment using indicator species through Species Distribution Modeling (SDM) was investigated. The bivalves: Corbula gibba and Flexopecten hyalinus were the indicator species characterizing disturbed and undisturbed areas respectively in terms of chlorophyll a concentration in Greece. The habitat suitability maps of these species reflected the overall ecological status of the area. The C. gibba model successfully predicted the occurrence of this species in areas with increased physical disturbance driven by chlorophyll a concentration, whereas the habitat map for F. hyalinus showed an increased probability of occurrence in chlorophyll-poor areas, affected mainly by salinity. We advocate the use of C. gibba as a proxy for eutrophication and the incorporation of this species in monitoring studies through SDM methods. For the Mediterranean Sea we suggest the use of F. hyalinus in SDM as an indicator of environmental stability and a possible forecasting tool for salinity fluctuations. Copyright © 2018 Elsevier Ltd. All rights reserved.

The species in primatology.

Science.gov (United States)

Groves, Colin

2014-01-01

Biologists of the late eighteenth and early nineteenth centuries all bandied about the term "species," but very rarely actually said what they meant by it. Often, however, one can get inside their thinking by piecing together some of their remarks. One of the most nearly explicit-appropriately, for the man who wrote a book called The Origin of Species - was Charles Darwin: "Practically, when a naturalist can unite two forms together by others having intermediate characters, he treats the one as a variety of the other… He later translated this into evolutionary terms: "Hereafter, we shall be compelled to acknowledge that the only distinction between species and well-marked varieties is, that the latter are known, or believed, to be connected at the present day by intermediate gradations, whereas species were formerly thus connected"(1:484-5.) Copyright © 2014 Wiley Periodicals, Inc.

Species delimitation of the Hyphydrus ovatus complex in western Palaearctic with an update of species distributions (Coleoptera, Dytiscidae

Directory of Open Access Journals (Sweden)

Johannes Bergsten

2017-06-01

Full Text Available The species status of Hyphydrus anatolicus Guignot, 1957 and H. sanctus Sharp, 1882, previously often confused with the widespread H. ovatus (Linnaeus, 1760, are tested with molecular and morphological characters. Cytochrome c oxidase subunit 1 (CO1 was sequenced for 32 specimens of all three species. Gene-trees were inferred with parsimony, time-free bayesian and strict clock bayesian analyses. The GMYC model was used to estimate species limits. All three species were reciprocally monophyletic with CO1 and highly supported. The GMYC species delimitation analysis unequivocally delimited the three species with no other than the three species solution included in the confidence interval. A likelihood ratio test rejected the one-species null model. Important morphological characters distinguishing the species are provided and illustrated. New distributional data are given for the following species: Hyphydrus anatolicus from Slovakia and Ukraine, and H. aubei Ganglbauer, 1891, and H. sanctus from Turkey.

Incorporating climate science in applications of the US endangered species act for aquatic species.

Science.gov (United States)

McClure, Michelle M; Alexander, Michael; Borggaard, Diane; Boughton, David; Crozier, Lisa; Griffis, Roger; Jorgensen, Jeffrey C; Lindley, Steven T; Nye, Janet; Rowland, Melanie J; Seney, Erin E; Snover, Amy; Toole, Christopher; VAN Houtan, Kyle

2013-12-01

Aquatic species are threatened by climate change but have received comparatively less attention than terrestrial species. We gleaned key strategies for scientists and managers seeking to address climate change in aquatic conservation planning from the literature and existing knowledge. We address 3 categories of conservation effort that rely on scientific analysis and have particular application under the U.S. Endangered Species Act (ESA): assessment of overall risk to a species; long-term recovery planning; and evaluation of effects of specific actions or perturbations. Fewer data are available for aquatic species to support these analyses, and climate effects on aquatic systems are poorly characterized. Thus, we recommend scientists conducting analyses supporting ESA decisions develop a conceptual model that links climate, habitat, ecosystem, and species response to changing conditions and use this model to organize analyses and future research. We recommend that current climate conditions are not appropriate for projections used in ESA analyses and that long-term projections of climate-change effects provide temporal context as a species-wide assessment provides spatial context. In these projections, climate change should not be discounted solely because the magnitude of projected change at a particular time is uncertain when directionality of climate change is clear. Identifying likely future habitat at the species scale will indicate key refuges and potential range shifts. However, the risks and benefits associated with errors in modeling future habitat are not equivalent. The ESA offers mechanisms for increasing the overall resilience and resistance of species to climate changes, including establishing recovery goals requiring increased genetic and phenotypic diversity, specifying critical habitat in areas not currently occupied but likely to become important, and using adaptive management. Incorporación de las Ciencias Climáticas en las Aplicaciones del

[Yeast species in vulvovaginitis candidosa].

Science.gov (United States)

Nemes-Nikodém, Éva; Tamási, Béla; Mihalik, Noémi; Ostorházi, Eszter

2015-01-04

Vulvovaginal candidiasis is the most common mycosis, however, the available information about antifungal susceptibilities of these yeasts is limited. To compare the gold standard fungal culture with a new molecular identification method and report the incidence of yeast species in vulvovaginitis candidosa. The authors studied 370 yeasts isolated from vulvovaginal candidiasis and identified them by phenotypic and molecular methods. The most common species was Candida albicans (85%), followed by Candida glabrata, and other Candida species. At present there are no recommendations for the evaluation of antifungal susceptibility of pathogenic fungal species occurring in vulvovaginal candidiasis and the natural antifungal resistance of the different species is known only. Matrix Assisted Laser Desorption Ionization Time of Flight identification can be used to differentiate the fluconazole resistant Candida dubliniensis and the sensitive Candida albicans strains.

Macroalgal biomass and species variations in the Lagoon of Venice (Northern Adriatic Sea, Italy: 1981-1998

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Daniele Curiel

2004-03-01

Full Text Available Over the past hundred years, the composition of the submerged aquatic vegetation of the Lagoon of Venice has changed considerably, due to increased anthropic activities and large-scale industrialisation. Seagrasses have gradually been reduced, whereas macroalgae (Ulva rigida, Enteromorpha spp., Cladophora spp., Chaetomorpha spp. have increased. Macroalgal overgrowths peaked between 1970 and 1990 to the extent that, in order to estimate macroalgal biomass and coverage, the Venice Magistrato alle Acque (the Lagoon water management authority started a series of investigations including monthly in situ measurements and aerial photo surveys. In the present paper these data are compared with available information on the Lagoon of Venice, and the widespread phenomenon of macroalgal proliferation is described. At the end of the 1980s, in our study area (78 km2 in the central part of the Lagoon biomass values ranged from 10 to 25 kg wet weight (w.w. m-2 (sub-areas of Lido and Sacca Sessola, with a total mean biomass of 392,000 t w.w. A slight reduction took place in 1992 and at the end of the 1990s the highest biomass values were relatively low, 5 kg w.w. m-2, with a total mean biomass of 1,600 t w.w. Our qualitative research carried out in 1991 on 130 sampling stations in the study area showed that soft substrates had a greatly reduced floristic composition in the five sub-areas in comparison with the control area (from 18 to 6 taxa, with Chlorophyta (50-80% prevailing over both Rhodophyta (14-38% and Phaeophyta (0-14%, and a slight or reduced distribution of seagrasses. The trend in macroalgal reduction during the 1990s corresponded to seagrass recolonisation, mainly of Zostera marina, taking advantage of new, compacted, oxidised and stabilised sediments that were no longer covered by extensive Ulva beds.

SpeciesGeoCoder: Fast Categorization of Species Occurrences for Analyses of Biodiversity, Biogeography, Ecology, and Evolution.

Science.gov (United States)

Töpel, Mats; Zizka, Alexander; Calió, Maria Fernanda; Scharn, Ruud; Silvestro, Daniele; Antonelli, Alexandre

2017-03-01

Understanding the patterns and processes underlying the uneven distribution of biodiversity across space constitutes a major scientific challenge in systematic biology and biogeography, which largely relies on effectively mapping and making sense of rapidly increasing species occurrence data. There is thus an urgent need for making the process of coding species into spatial units faster, automated, transparent, and reproducible. Here we present SpeciesGeoCoder, an open-source software package written in Python and R, that allows for easy coding of species into user-defined operational units. These units may be of any size and be purely spatial (i.e., polygons) such as countries and states, conservation areas, biomes, islands, biodiversity hotspots, and areas of endemism, but may also include elevation ranges. This flexibility allows scoring species into complex categories, such as those encountered in topographically and ecologically heterogeneous landscapes. In addition, SpeciesGeoCoder can be used to facilitate sorting and cleaning of occurrence data obtained from online databases, and for testing the impact of incorrect identification of specimens on the spatial coding of species. The various outputs of SpeciesGeoCoder include quantitative biodiversity statistics, global and local distribution maps, and files that can be used directly in many phylogeny-based applications for ancestral range reconstruction, investigations of biome evolution, and other comparative methods. Our simulations indicate that even datasets containing hundreds of millions of records can be analyzed in relatively short time using a standard computer. We exemplify the use of SpeciesGeoCoder by inferring the historical dispersal of birds across the Isthmus of Panama, showing that lowland species crossed the Isthmus about twice as frequently as montane species with a marked increase in the number of dispersals during the last 10 million years. [ancestral area reconstruction; biodiversity

A Framework for Spatial Risk Assessments: Potential Impacts of Nonindigenous Invasive Species on Native Species

Directory of Open Access Journals (Sweden)

Craig R. Allen

2006-06-01

Full Text Available Many populations of wild animals and plants are declining and face increasing threats from habitat fragmentation and loss as well as exposure to stressors ranging from toxicants to diseases to invasive nonindigenous species. We describe and demonstrate a spatially explicit ecological risk assessment that allows for the incorporation of a broad array of information that may influence the distribution of an invasive species, toxicants, or other stressors, and the incorporation of landscape variables that may influence the spread of a species or substances. The first step in our analyses is to develop species models and quantify spatial overlap between stressor and target organisms. Risk is assessed as the product of spatial overlap and a hazard index based on target species vulnerabilities to the stressor of interest. We illustrate our methods with an example in which the stressor is the ecologically destructive nonindigenous ant, Solenopsis invicta, and the targets are two declining vertebrate species in the state of South Carolina, USA. A risk approach that focuses on landscapes and that is explicitly spatial is of particular relevance as remaining undeveloped lands become increasingly uncommon and isolated and more important in the management and recovery of species and ecological systems. Effective ecosystem management includes the control of multiple stressors, including invasive species with large impacts, understanding where those impacts may be the most severe, and implementing management strategies to reduce impacts.

Genomic definition of species. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Crkvenjakov, R.; Dramanac, R.

1992-06-01

A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called (species) genome. The definition of species based on chromosomes, genes, or genome common to its member organisms has been implied or mentioned in passing numerous times. Some population biologists think that members of species have similar ``homeostatic genotypes,`` which are to a degree resistant to mutation or environmental change in the production of a basic phenotype.

Alien species on the coasts of Turkey

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M.E. CINAR

2005-12-01

Full Text Available The compilation of data on alien species reported from the Turkish coasts yielded a total of 263 species belonging to 11 systematic groups, of which Mollusca had the highest number of species (85 species, followed by Crustacea (51, fishes (43 and phytobenthos (39. The Black Sea is represented by a total of 20 alien species, the Sea of Marmara by 48 species, the Aegean Sea by 98 species and the Levantine Sea by 202 species. The majority of aliens found in the Black Sea and the Sea of Marmara were transported via shipping, whereas the Levantine coast is extensively subjected to Lessepsian migration. Benthic habitats (soft and hard substrata comprise 76% of the total alien species and the pelagic environment is inhabited by thirty-nine species. Almost 50% of aliens collected from the Turkish coasts were found only at 0-10 m depth. Eight species occur at depths deeper than 100 m. The impacts of aliens on the benthic and pelagic ecosystems are presented.

The Tetramorium tortuosum species group (Hymenoptera, Formicidae, Myrmicinae revisited - taxonomic revision of the Afrotropical T. capillosum species complex

Directory of Open Access Journals (Sweden)

Francisco Hita Garcia

2013-05-01

Full Text Available In this study we revise the taxonomy of the Tetramorium tortuosum species group members encountered in the Afrotropical region, which we have placed in its own subgroup: the T. capillosum species complex. We re-describe the two previously known species T. capillosum Bolton and T. tabarum Bolton, and describe the new species T. hecate sp. n. The geographic distribution of the three species appears to be restricted to the equatorial rainforests of Central Africa. We provide a diagnosis of the T. capillosum species complex, an illustrated identification key to species level, and worker-based species descriptions, which include diagnoses, discussions, high-quality montage images, and distribution maps. Furthermore, we discuss biogeography and composition of the globally distributed T. tortuosum group.

Integrative taxonomy by molecular species delimitation: multi-locus data corroborate a new species of Balkan Drusinae micro-endemics.

Science.gov (United States)

Vitecek, Simon; Kučinić, Mladen; Previšić, Ana; Živić, Ivana; Stojanović, Katarina; Keresztes, Lujza; Bálint, Miklós; Hoppeler, Felicitas; Waringer, Johann; Graf, Wolfram; Pauls, Steffen U

2017-06-06

Taxonomy offers precise species identification and delimitation and thus provides basic information for biological research, e.g. through assessment of species richness. The importance of molecular taxonomy, i.e., the identification and delimitation of taxa based on molecular markers, has increased in the past decade. Recently developed exploratory tools now allow estimating species-level diversity in multi-locus molecular datasets. Here we use molecular species delimitation tools that either quantify differences in intra- and interspecific variability of loci, or divergence times within and between species, or perform coalescent species tree inference to estimate species-level entities in molecular genetic datasets. We benchmark results from these methods against 14 morphologically readily differentiable species of a well-defined subgroup of the diverse Drusinae subfamily (Trichoptera, Limnephilidae). Using a 3798 bp (6 loci) molecular data set we aim to corroborate a geographically isolated new species by integrating comparative morphological studies and molecular taxonomy. Our results indicate that only multi-locus species delimitation provides taxonomically relevant information. The data further corroborate the new species Drusus zivici sp. nov. We provide differential diagnostic characters and describe the male, female and larva of this new species and discuss diversity patterns of Drusinae in the Balkans. We further discuss potential and significance of molecular species delimitation. Finally we argue that enhancing collaborative integrative taxonomy will accelerate assessment of global diversity and completion of reference libraries for applied fields, e.g., conservation and biomonitoring.

The role of biotic interactions in shaping distributions and realised assemblages of species: implications for species distribution modelling.

Science.gov (United States)

Wisz, Mary Susanne; Pottier, Julien; Kissling, W Daniel; Pellissier, Loïc; Lenoir, Jonathan; Damgaard, Christian F; Dormann, Carsten F; Forchhammer, Mads C; Grytnes, John-Arvid; Guisan, Antoine; Heikkinen, Risto K; Høye, Toke T; Kühn, Ingolf; Luoto, Miska; Maiorano, Luigi; Nilsson, Marie-Charlotte; Normand, Signe; Öckinger, Erik; Schmidt, Niels M; Termansen, Mette; Timmermann, Allan; Wardle, David A; Aastrup, Peter; Svenning, Jens-Christian

2013-02-01

Predicting which species will occur together in the future, and where, remains one of the greatest challenges in ecology, and requires a sound understanding of how the abiotic and biotic environments interact with dispersal processes and history across scales. Biotic interactions and their dynamics influence species' relationships to climate, and this also has important implications for predicting future distributions of species. It is already well accepted that biotic interactions shape species' spatial distributions at local spatial extents, but the role of these interactions beyond local extents (e.g. 10 km(2) to global extents) are usually dismissed as unimportant. In this review we consolidate evidence for how biotic interactions shape species distributions beyond local extents and review methods for integrating biotic interactions into species distribution modelling tools. Drawing upon evidence from contemporary and palaeoecological studies of individual species ranges, functional groups, and species richness patterns, we show that biotic interactions have clearly left their mark on species distributions and realised assemblages of species across all spatial extents. We demonstrate this with examples from within and across trophic groups. A range of species distribution modelling tools is available to quantify species environmental relationships and predict species occurrence, such as: (i) integrating pairwise dependencies, (ii) using integrative predictors, and (iii) hybridising species distribution models (SDMs) with dynamic models. These methods have typically only been applied to interacting pairs of species at a single time, require a priori ecological knowledge about which species interact, and due to data paucity must assume that biotic interactions are constant in space and time. To better inform the future development of these models across spatial scales, we call for accelerated collection of spatially and temporally explicit species data. Ideally

Lichen species preference by reindeer

Energy Technology Data Exchange (ETDEWEB)

Holleman, D F; Luick, J R

1977-08-01

The preference by reindeer for five species of lichens commonly found on Central Alaska rangelands was tested under controlled laboratory conditions. Results indicate that reindeer are strongly selective species in their lichen grazing habits. The five tested species ranged as follows in order of decreasing acceptibility: Caldonia alpestris, C. rangiferina, Stereocaulon paschale, Cetraria richardsonii, and Peltigera aphthosa.

Endangered Lilium Species of Turkey

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Sevim Demir

2018-01-01

Full Text Available Turkey, which is among the major gene centers of the world and has a special place in plant genetic diversity. However, many plant genetic resources, including geophytes, are under genetic erosion because of the environmental and other problems and therefore face with the danger of extinction. Lilium ciliatum is endemic to North East Anatolia. IUCN (International Union for the Conservation of Natural Resources Red List Category of this species is Endangered (EN. Lilium ciliatum naturally grown in Zigana pass, Bayburt, Trabzon, Bulancak, Giresun and Gümüşhane is endangered and major threats of L. ciliatum are road construction and human disturbance related to ecotourism and recreation. It was reported that Lilium carniolicum naturally grown in Turkey is endangered although it isn’t in the IUCN Red List. Distribution areas of L. carniolicum are Trabzon, Rize, Artvin and it is also endemic to North East Anatolia. These species have high potential for use as ornamental plants with their colorful big flowers. In addition, the bulbs of these species are also used in the cosmetic industry and medicine. These are the main properties that increase the importance of L. ciliatum and L. carniolicum species. Therefore it is very important to protect the habitats of these species, ensure the continuity of their generations. The disappearance of these endemic species from our country means to disappear from the world. This review has been given in order to give some information about the endangered Lilium species of Turkey and conservation actions on these species in Turkey flora and take attention to the issue.

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.

Eighteen microsatellite loci in Salix arbutifolia (Salicaceae) and cross-species amplification in Salix and Populus species.

Science.gov (United States)

Hoshikawa, Takeshi; Kikuchi, Satoshi; Nagamitsu, Teruyoshi; Tomaru, Nobuhiro

2009-07-01

Salix arbutifolia is a riparian dioecious tree species that is of conservation concern in Japan because of its highly restricted distribution. Eighteen polymorphic loci of dinucleotide microsatellites were isolated and characterized. Among these, estimates of the expected heterozygosity ranged from 0.350 to 0.879. Cross-species amplification was successful at 9-13 loci among six Salix species and at three loci in one Populus species. © 2009 Blackwell Publishing Ltd.

Discordance between morphological and molecular species boundaries among Caribbean species of the reef sponge Callyspongia.

Science.gov (United States)

DeBiasse, Melissa B; Hellberg, Michael E

2015-02-01

Sponges are among the most species-rich and ecologically important taxa on coral reefs, yet documenting their diversity is difficult due to the simplicity and plasticity of their morphological characters. Genetic attempts to identify species are hampered by the slow rate of mitochondrial sequence evolution characteristic of sponges and some other basal metazoans. Here we determine species boundaries of the Caribbean coral reef sponge genus Callyspongia using a multilocus, model-based approach. Based on sequence data from one mitochondrial (COI), one ribosomal (28S), and two single-copy nuclear protein-coding genes, we found evolutionarily distinct lineages were not concordant with current species designations in Callyspongia. While C. fallax,C. tenerrima, and C. plicifera were reciprocally monophyletic, four taxa with different morphologies (C. armigera,C. longissima,C. eschrichtii, and C. vaginalis) formed a monophyletic group and genetic distances among these taxa overlapped distances within them. A model-based method of species delimitation supported collapsing these four into a single evolutionary lineage. Variation in spicule size among these four taxa was partitioned geographically, not by current species designations, indicating that in Callyspongia, these key taxonomic characters are poor indicators of genetic differentiation. Taken together, our results suggest a complex relationship between morphology and species boundaries in sponges.

Hierarchical species distribution models

Science.gov (United States)

Hefley, Trevor J.; Hooten, Mevin B.

2016-01-01

Determining the distribution pattern of a species is important to increase scientific knowledge, inform management decisions, and conserve biodiversity. To infer spatial and temporal patterns, species distribution models have been developed for use with many sampling designs and types of data. Recently, it has been shown that count, presence-absence, and presence-only data can be conceptualized as arising from a point process distribution. Therefore, it is important to understand properties of the point process distribution. We examine how the hierarchical species distribution modeling framework has been used to incorporate a wide array of regression and theory-based components while accounting for the data collection process and making use of auxiliary information. The hierarchical modeling framework allows us to demonstrate how several commonly used species distribution models can be derived from the point process distribution, highlight areas of potential overlap between different models, and suggest areas where further research is needed.

Sub specie aeternitatis

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Laura Gioeni

2012-10-01

Full Text Available Per delineare il rapporto tra etica ed estetica nell'architettura e rispondere alla domanda principale «che cosa è o dovrebbe essere un buon architetto?», il saggio discute la tesi di Wittgenstein secondo cui «l'opera d'arte è l'oggetto visto sub specie aeternitatis e la vita buona è il mondo visto sub specie aeternitatis. Questa è la connessione tra arte ed etica».

The definition of species richness used by species sensitivity distributions approximates observed effects of salinity on stream macroinvertebrates

Energy Technology Data Exchange (ETDEWEB)

Kefford, Ben J., E-mail: ben.kefford@uts.edu.a [School of Applied Sciences, RMIT University, Victoria (Australia); Centre for Environmental Sustainability, Department of Environmental Science, University of Technology Sydney, New South Wales (Australia); Marchant, Richard [Department of Entomology, Museum of Victoria, Victoria (Australia); Schaefer, Ralf B. [School of Applied Sciences, RMIT University, Victoria (Australia); Metzeling, Leon [EPA Victoria, Macleod, Victoria (Australia); Dunlop, Jason E. [Department of Environment and Resource Management, Indooroopilly, Queensland (Australia); National Research Centre for Environmental Toxicology, University of Queensland, Coopers Plains, Queensland (Australia); Choy, Satish C. [Department of Environment and Resource Management, Indooroopilly, Queensland (Australia); Goonan, Peter [South Australia Environment Protection Authority, Adelaide, South Australia (Australia)

2011-01-15

The risk of chemicals for ecological communities is often forecast with species sensitivity distributions (SSDs) which are used to predict the concentration which will protect p% of species (PC{sub p} value). However, at the PC{sub p} value, species richness in nature would not necessary be p% less than at uncontaminated sites. The definition of species richness inherent to SSDs (contaminant category richness) contrasts with species richness typically measured in most field studies (point richness). We determine, for salinity in eastern Australia, whether these definitions of stream macroinvertebrate species richness are commensurable. There were strong relationships (r{sup 2} {>=} 0.87) between mean point species, family and Ephemeroptera, Trichoptera and Plecoptera species richness and their respective contamination category richness. Despite differences in the definition of richness used by SSDs and field biomonitoring, their results in terms of relative species loss from salinity in south-east Australia are similar. We conclude that in our system both definitions are commensurable. - Definitions of species richness inherit in SSDs and biomonitoring are for salinity in south-east Australia commensurable.

The definition of species richness used by species sensitivity distributions approximates observed effects of salinity on stream macroinvertebrates

International Nuclear Information System (INIS)

Kefford, Ben J.; Marchant, Richard; Schaefer, Ralf B.; Metzeling, Leon; Dunlop, Jason E.; Choy, Satish C.; Goonan, Peter

2011-01-01

The risk of chemicals for ecological communities is often forecast with species sensitivity distributions (SSDs) which are used to predict the concentration which will protect p% of species (PC p value). However, at the PC p value, species richness in nature would not necessary be p% less than at uncontaminated sites. The definition of species richness inherent to SSDs (contaminant category richness) contrasts with species richness typically measured in most field studies (point richness). We determine, for salinity in eastern Australia, whether these definitions of stream macroinvertebrate species richness are commensurable. There were strong relationships (r 2 ≥ 0.87) between mean point species, family and Ephemeroptera, Trichoptera and Plecoptera species richness and their respective contamination category richness. Despite differences in the definition of richness used by SSDs and field biomonitoring, their results in terms of relative species loss from salinity in south-east Australia are similar. We conclude that in our system both definitions are commensurable. - Definitions of species richness inherit in SSDs and biomonitoring are for salinity in south-east Australia commensurable.

Two new species of Aulospongus Norman, 1878 with a key to the Atlantic species (Poecilosclerida; Demospongiae; Porifera).

Science.gov (United States)

Cavalcanti, Thaynã; Santos, George Garcia; Pinheiro, Ulisses

2014-07-03

We describe two new species: Aulospongus trirhabdostylus sp. nov. and Aulospongus mandela sp. nov. from Potiguar Basin (Rio Grande do Norte State, Northeastern Brazil). Both species were compared with their congeners and an identification key for the Atlantic species of Aulospongus is provided. The genus Aulospongus now contains 16 species.

Systematics of the Dendropsophus leucophyllatus species complex (Anura: Hylidae): Cryptic diversity and the description of two new species

Science.gov (United States)

Caminer, Marcel A.; Milá, Borja; Jansen, Martin; Fouquet, Antoine; Venegas, Pablo J.; Chávez, Germán; Lougheed, Stephen C.

2017-01-01

Genetic data in studies of systematics of Amazonian amphibians frequently reveal that purportedly widespread single species in reality comprise species complexes. This means that real species richness may be significantly higher than current estimates. Here we combine genetic, morphological, and bioacoustic data to assess the phylogenetic relationships and species boundaries of two Amazonian species of the Dendropsophus leucophyllatus species group: D. leucophyllatus and D. triangulum. Our results uncovered the existence of five confirmed and four unconfirmed candidate species. Among the confirmed candidate species, three have available names: Dendropsophus leucophyllatus, Dendropsophus triangulum, and Dendropsophus reticulatus, this last being removed from the synonymy of D. triangulum. A neotype of D. leucophyllatus is designated. We describe the remaining two confirmed candidate species, one from Bolivia and another from Peru. All confirmed candidate species are morphologically distinct and have much smaller geographic ranges than those previously reported for D. leucophyllatus and D. triangulum sensu lato. Dendropsophus leucophyllatus sensu stricto occurs in the Guianan region. Dendropsophus reticulatus comb. nov. corresponds to populations in the Amazon basin of Brazil, Ecuador, and Peru previously referred to as D. triangulum. Dendropsophus triangulum sensu stricto is the most widely distributed species; it occurs in Amazonian Ecuador, Peru and Brazil, reaching the state of Pará. We provide accounts for all described species including an assessment of their conservation status. PMID:28248998

Four new species of frogs and one new species of snake from the Chapare region of Bolivia, with notes on other species

Science.gov (United States)

Reynolds, R.P.; Foster, M.S.

1992-01-01

We report on a collection of 74 frogs, 11 lots of frog eggs or tadpoles, and two snakes collected from the Chapare Region in the yungas of the eastern Andean Cordillera de Cochabamba, Bolivia. Collecting localities range from approximately 300 m to >3200 m in elevation. The specimens pertain to 23 species, probably 10 of which are undescribed. We describe four new species of frogs, one each in the genera Bufo, Centrolenella, Colostethus, and Hyla, and one new species of snake, genus Dipsas. We place Atelopus rugulosus in synonymy with A. tricolor.

Epilithic algal assemblages in the Forsmark Biotest basin

Energy Technology Data Exchange (ETDEWEB)

Snoeijs, P.

1987-04-01

The Forsmark Biotest Basin is an artificial offshore brackish lake, through which the cooling water is led from the Forsmark Nuclear Power Station on the Swedish east coast. The Biotest Basin differs from the Bothnian Sea surrounding it by a temperature elevation of up to 10 degrees C, no ice cover in winter, and an artificial, fast current. At 11 sites in- and outside the basin, benthic algal assemblages on stones in the hydrolittoral belt were sampled every third week during one year. Cover abundances were estimated for all algae occurring on the stones, but for diatoms only when they formed blooms. The results of the vegetation analyses are given. 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. The algae included both unicellular and multicellular forms. In total 88 taxa were distinguished in the species lists: 29 Cyanophyta, 7 Rhodophyta, 1 Chrysophyceae, 9 Fucophyceae, 17 Diatomophyceae and 25 Chlorophyta. In terms of percentage cover-abundance, blue-green and green algae increased with temperature, while red and brown algae and diatoms decreased with temperature in the interval between the minimum (0 degrees C) and the maximum (25.7 degrees C) water temperatures that were measured during the investigation period. Melosira spp. and Nitzschia filiformis proved to be the diatoms most favoured by the cooling water discharge. Lower diversity and greater dominance of one or a few species over the other was caused by thermal discharge at sites with fast-flowing water, but the opposite occurred at sites with quiescent water, mainly due to a greater number and higher abundances of blue-green algal species and thread-like green algae at the latter sites. This report also gives some notes on taxonomy of the encountered species.

Deriving field-based species sensitivity distributions (f-SSDs) from stacked species distribution models (S-SDMs).

Science.gov (United States)

Schipper, Aafke M; Posthuma, Leo; de Zwart, Dick; Huijbregts, Mark A J

2014-12-16

Quantitative relationships between species richness and single environmental factors, also called species sensitivity distributions (SSDs), are helpful to understand and predict biodiversity patterns, identify environmental management options and set environmental quality standards. However, species richness is typically dependent on a variety of environmental factors, implying that it is not straightforward to quantify SSDs from field monitoring data. Here, we present a novel and flexible approach to solve this, based on the method of stacked species distribution modeling. First, a species distribution model (SDM) is established for each species, describing its probability of occurrence in relation to multiple environmental factors. Next, the predictions of the SDMs are stacked along the gradient of each environmental factor with the remaining environmental factors at fixed levels. By varying those fixed levels, our approach can be used to investigate how field-based SSDs for a given environmental factor change in relation to changing confounding influences, including for example optimal, typical, or extreme environmental conditions. This provides an asset in the evaluation of potential management measures to reach good ecological status.

Sea Cucumber (Holothuroidea Species of Turkey

Directory of Open Access Journals (Sweden)

Mehmet AYDIN

2016-11-01

Full Text Available There are nearly 1200 sea cucumber species in the world oceans, while only 37 species from Holothuroidea class lives in the Mediterranean Sea. This preliminary study aims identification sea cucumbers species of the Turkish waters. The sea cucumber samples used in this study were obtained from a series of different studies between the years of 2008 and 2014. Identification of the species are mainly based on the morphometric characteristics while some of species are determined from their calcareous spicules. Eight sea species were identified in this research which are; Holothuria tubulosa, Holothuria polii, Holothuria mammata, Holothuria (Platyperona sanctori, Holothuria forskali, Stichopus regalis, Synaptula reciprocans and Stereoderma kirschbergi. There are limited number of studies in the literature focusing on the identification of the sea cucumber species spread in our seas. Therefore, this study is believed to play an important role in guiding future researches.

Floristic analysis of perennial species on flowerbeds in Belgrade with special attention on invasiveness of the recorded species

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Popović Marija

2012-01-01

Full Text Available Urban areas are among the most important centres of invasive plant species distribution due to their richness in alien species. Because of that, a detailed floristic analysis of perennial flowerbeds was conducted in the central parks of Belgrade. A total of 53 perennial species were found, of which 55% were the alien species planted on 75% of the research area. Among them, two species (Aster novi belgii and Solidago canadensis are invasive and six species are potentially invasive in Serbia. These are planted on 5% and 20% of the flowerbeds, respectively. We can conclude that both the experts and institutions should be informed about the invasive species and potential damages. In the meantime, planting of native decorative species should be encouraged, since they will not pose a threat to natural habitats. Also, detailed research should be conducted in order to eradicate invasive and potentially invasive species from the surfaces around the research area.

New species of Bacuma Cameron (Hymenoptera: Braconidae: Braconinae) from Kenya and West Darfur with a key to species.

Science.gov (United States)

Quicke, Donald L J; Guy, Travis J; Noort, Simon VAN; Broad, Gavin R; Butcher, Buntika A

2017-05-08

Three new species of the Afrotropical braconine wasp genus Bacuma are described, and biological observations (nectar feeding) by one of them are noted. The new species are: B. kayserae Quicke & Butcher sp. nov. from Kenya, B. madiensis Quicke & Butcher sp. nov. from Uganda and B. darfurensis Quicke & Butcher sp. nov. from Sudan. A group of four large nominal species with red metasomas and finely sculptured tergites (B. granulatus, B. maculipennis, B. rufa and B. whitei) may represent a single widespread species or a pair of species separated by mesoscutum colour, or four separate but morphologically very similar species. However, given the small number of specimens available for study and the poor condition of some of these, including the types, they are not formally synonymised here. A partial key to the species of Bacuma is presented, which recognizes those species that are clearly distinct, including three new species. Interactive Lucid dichotomous and matrix keys are available on www.waspweb.org.

Molecular and morphological approaches for species delimitation and hybridization investigations of two Cichla species

Directory of Open Access Journals (Sweden)

Andrea A. F. Mourão

Full Text Available ABSTRACT The hybridization is a widely-discussed issue in several studies with fish species. For some authors, hybridization may be related with diversification and speciation of several groups, or also with the extinction of populations or species. Difficulties to differentiate species and hybrids may be a problem to correctly apply a management of wild species, because hybrid lineages, especially the advanced ones, may resemble the parental species. The genus Cichla Bloch & Schneider, 1801 constitutes an interesting experimental model, considering that hybridization and taxonomic uncertainties hinder a correct identification. Considering these problems, in this study, we developed genetic methodologies and applied meristic and morphometric approaches in wild samples in order to identify species and for test a possible hybridization between Cichla kelberi Kullander & Ferreira, 2006 and Cichla piquiti Kullander & Ferreira, 2006. For this, C. kelberi, C. piquiti and potential hybrid ( carijó individuals were collected in Paraná and Tietê rivers (SP, Brazil. For meristic and morphometric methods, the individuals were analyzed using the statistical software Pcord 5:31, while for molecular methods, primers for PCR-multiplex were designed and enzyme for PCR-RFLP were selected, under the species-specific nucleotide. All results indicated that the carijó is not an interspecific hybrid, because it presented identical genetic pattern and morphology closed to C. piquiti. Thus, we propose that carijó is a C. piquiti morphotype. In addition, this study promotes a new molecular tool that could be used in future research, monitoring and management programs of the genus Cichla.

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.

Studies on {sup 232}Th and {sup 238}U levels in marine algae collected from the coast of Niigata Prefecture

Energy Technology Data Exchange (ETDEWEB)

Kato, Kenji; Tonouchi, Shigemasa; Maruta, Fumiyuki; Ebata, Hidekazu [Niigata Prefectural Inst. of Public Health and Environmental Sciences (Japan)

2001-12-01

To evaluate the properties of algae to concentrate radioactive elements, 14 species of algae like Sargassum were collected in the Prefecture and analyzed for their {sup 232}Th and {sup 238}U levels with Yokogawa HP4500 ICP-MS apparatus. The places of collection included those near the water discharge of an atomic power station. Mean {sup 232}Th and {sup 238}U levels were found to be 120 and 260 ng/g dry wt, respectively, and Phaeophyta showed more than several times higher {sup 238}U level than Chlorophyta and Rhodophyta. There was no clear difference in {sup 232}Th levels. No difference between places of collection was observed in Sargassum {sup 232}Th or {sup 238}U level. Adsorption of {sup 232}Th particle to and incorporation of soluble {sup 238}U into algae body were suggested. Mean {sup 232}Th and {sup 238}U radioactivities were found 73 and 510 {mu}Bq/g wet wt, respectively, and the respective annual committed effective doses, 0.2 and 0.3 {mu}Sv, calculated from those values were confirmed to be enough lower than the annual public dose limit, 1 mSv. (K.H.)

KINERJA ENZIM GANDA PADA PRETREATMENT MIKROALGA UNTUK PRODUKSI BIOETANOL

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Padil

2016-12-01

Full Text Available The use of biomass of microalgae as a feedstock to produce bioethanol is very promising, it is caused by a large amount of carbohydrates contained in microalgae physiology cell. The main obstacle of enzymatic hydrolysis in order to produce bioethanol is the bound starch granules in a rigid cell wall. Therefore, pre-treatment steps needed to remove and convert complex carbohydrates into simple sugars before the fermentation process. Tetraselmis Chuii microalgae species are green microalgae (Chlorophyta in which the cell wall containing cellulose and hemicellulose as the main constituent, therefore, this study observe the effect of the use of cellulase enzymes and xylanase as a strategy to open up the cell walls of microalgae. Another investigated parameter is the enzyme concentration, temperature, pH, and methods of use of enzymes. The results showed that the highest yield of glucose obtained was 31.912% (w / w and is achieved under the conditions of a temperature of 45oC, pH of 4.5, the amount of biomass of microalgae as 5 g/L, the concentration of cellulase enzymes and xilanase 30% (w / w at 40 minute at mechanism using cellulase and xylanase enzymes simultaneously.

Chapter 16: Species Diversity

African Journals Online (AJOL)

zargaran

2012-05-03

May 3, 2012 ... rarefaction method was recorded in Pardanan, with 28 oak gall wasps species. Furthermore, the highest amount of Gini-Simpson and Shannon entropy index were recorded in Sardasht, while the highest evenness was recorded in Shalmash. Differences in the local distribution of oak species, especially.

The Origin of Species

NARCIS (Netherlands)

Darwin, Charles

2005-01-01

In The Origin of Species Darwin outlined his theory of evolution, which proposed that species had been evolving and differentiating over time under the influence of natural selection. On its publication it became hugely influential, bringing about a seismic shift in the scientific view of humanitys

Support your local species

DEFF Research Database (Denmark)

Stärk, Johanna

Nearly a quarter of all animal species within the European Union are threatened with extinction. Protecting many of these species will require the full spectrum of conservation actions from in-situ to ex-situ management. Holding an estimated 44% of EU Red Listed terrestrial vertebrates, zoos hereby...

Socially-parasitic Myrmica species (Hymenoptera, Formicidae) of Himalaya, with the description of a new species.

Science.gov (United States)

Bharti, Himender; Radchenko, Alexander; Sasi, Sishal

2016-01-01

A new socially-parasitic species, Myrmica latra sp. n. is described based on a queen and male from Indian Himalaya. Its queen differs from other species by the distinctly narrower petiole and postpetiole, blunt and non-divergent propodeal spines, and a darker body colour. The taxonomic position of the three known Himalayan socially-parasitic Myrmica species is discussed, and Myrmica ereptrix Bolton 1988 is transferred to the smythiesii species-group. It is supposed that Myrmica nefaria Bharti 2012 is a temporary social parasite, but Myrmica ereptrix and Myrmica latra sp. n. are permanent social parasites, and a key for their identification is provided.

Species concepts, species delimitation and the inherent limitations

Indian Academy of Sciences (India)

Frank Zachos

synchrony and to sexually reproducing organisms would not be a problem anymore ... approach to species delimitation that combines genetic data with .... The datasets or algorithms could then be modified so that the groups yielded conform.

Does temperature-mediated reproductive success drive the direction of species displacement in two invasive species of leafminer fly?

Directory of Open Access Journals (Sweden)

Haihong Wang

Full Text Available Liriomyza sativae and L. trifolii (Diptera: Agromyzidae are two highly invasive species of leafmining flies, which have become established as pests of horticultural crops throughout the world. In certain regions where both species have been introduced, L. sativae has displaced L. trifolii, whereas the opposite has occurred in other regions. These opposing outcomes suggest that neither species is an inherently superior competitor. The regions where these displacements have been observed (southern China, Japan and western USA are climatically different. We determined whether temperature differentially affects the reproductive success of these species and therefore if climatic differences could affect the outcome of interspecific interactions where these species are sympatric. The results of life table parameters indicate that both species can develop successfully at all tested temperatures (20, 25, 31, 33°C. L. sativae had consistently higher fecundities at all temperatures, but L. trifolii developed to reproductive age faster. Age-stage specific survival rates were higher for L. sativae at low temperatures, but these were higher for L. trifolii at higher temperatures. We then compared the net reproductive rates (R0 for both species in pure and mixed cultures maintained at the same four constant temperatures. Both species had significantly lower net reproductive rates in mixed species cultures compared with their respective pure species cultures, indicating that both species are subject to intense interspecific competition. Net reproductive rates were significantly greater for L. sativae than for L. trifolii in mixed species groups at the lower temperatures, whereas the opposite occurred at the higher temperature. Therefore, interactions between the species are temperature dependent and small differences could shift the competitive balance between the species. These temperature mediated effects may contribute to the current ongoing displacement

Protectiveness of Species Sensitivity Distribution Hazard Concentrations for Acute Toxicity Used in Endangered Species Risk Assessment

Science.gov (United States)

A primary objective of threatened and endangered species conservation is to ensure that chemical contaminants and other stressors do not adversely affect listed species. Assessments of the ecological risks of chemical exposures to listed species often rely on the use of surrogate...

The nature of plant species.

Science.gov (United States)

Rieseberg, Loren H; Wood, Troy E; Baack, Eric J

2006-03-23

Many botanists doubt the existence of plant species, viewing them as arbitrary constructs of the human mind, as opposed to discrete, objective entities that represent reproductively independent lineages or 'units of evolution'. However, the discreteness of plant species and their correspondence with reproductive communities have not been tested quantitatively, allowing zoologists to argue that botanists have been overly influenced by a few 'botanical horror stories', such as dandelions, blackberries and oaks. Here we analyse phenetic and/or crossing relationships in over 400 genera of plants and animals. We show that although discrete phenotypic clusters exist in most genera (> 80%), the correspondence of taxonomic species to these clusters is poor (< 60%) and no different between plants and animals. Lack of congruence is caused by polyploidy, asexual reproduction and over-differentiation by taxonomists, but not by contemporary hybridization. Nonetheless, crossability data indicate that 70% of taxonomic species and 75% of phenotypic clusters in plants correspond to reproductively independent lineages (as measured by postmating isolation), and thus represent biologically real entities. Contrary to conventional wisdom, plant species are more likely than animal species to represent reproductively independent lineages.

Two new species of nocturnal bees of the genus Megalopta (Hymenoptera: Halictidae) with keys to species

OpenAIRE

Gonzalez, Victor H; Griswold, Terry; Ayala, Ricardo

2010-01-01

Megalopta Smith, 1853, is a Neotropical genus of nocturnal or crepuscular bees. Two subgenera are recognized with most of its nearly 30 species placed in the nominate subgenus. Species of Megalopta s. str. are more commonly collected than species of Noctoraptor Engel et al. 1997, all presumably parasites of Megalopta s. str. Two new species of Megalopta are described here: M. (Megalopta) tetewana, n. sp., from Mexico and M. (Noctoraptor) huaoranii, n. sp., from Ecuador. Identification keys to...

Genomic definition of species. Revision 2

Energy Technology Data Exchange (ETDEWEB)

Crkvenjakov, R.; Drmanac, R.

1993-03-01

A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species- and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called species genome. Our proposal for the definition of a biological species is as follows: A species comprises a group of actual and potential biological organisms built according to a unique genome program that is recorded, and at least in part expressed, in the structures of their genomic nucleic acid molecule(s), having intragroup sequence differences which can be fully interconverted in the process of organismal reproduction.

Effects of species biological traits and environmental heterogeneity on simulated tree species distribution shifts under climate change.

Science.gov (United States)

Wang, Wen J; He, Hong S; Thompson, Frank R; Spetich, Martin A; Fraser, Jacob S

2018-09-01

Demographic processes (fecundity, dispersal, colonization, growth, and mortality) and their interactions with environmental changes are not well represented in current climate-distribution models (e.g., niche and biophysical process models) and constitute a large uncertainty in projections of future tree species distribution shifts. We investigate how species biological traits and environmental heterogeneity affect species distribution shifts. We used a species-specific, spatially explicit forest dynamic model LANDIS PRO, which incorporates site-scale tree species demography and competition, landscape-scale dispersal and disturbances, and regional-scale abiotic controls, to simulate the distribution shifts of four representative tree species with distinct biological traits in the central hardwood forest region of United States. Our results suggested that biological traits (e.g., dispersal capacity, maturation age) were important for determining tree species distribution shifts. Environmental heterogeneity, on average, reduced shift rates by 8% compared to perfect environmental conditions. The average distribution shift rates ranged from 24 to 200myear -1 under climate change scenarios, implying that many tree species may not able to keep up with climate change because of limited dispersal capacity, long generation time, and environmental heterogeneity. We suggest that climate-distribution models should include species demographic processes (e.g., fecundity, dispersal, colonization), biological traits (e.g., dispersal capacity, maturation age), and environmental heterogeneity (e.g., habitat fragmentation) to improve future predictions of species distribution shifts in response to changing climates. Copyright © 2018 Elsevier B.V. All rights reserved.

Diversification of Cercopithifilaria species (Nematoda: Filarioidea in Japanese wild ruminants with description of two new species

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Uni S.

2002-12-01

Full Text Available Twelve of the 17 Cervus nippon nippon deer from Kyushu Island, Japan, that we examined were infected with one or two Cercopithifilaria species. C. longa n. sp. adults were in the subcutaneous tissues of limbs and the abdomen, and C. crassa n. sp. adults were in the skin, mainly in the anterior part of the back ; the distribution of the dermal microfilariae generally matched that of the adult worms. The two new species were assigned to the group of primitive Cercopithifilaria species that parasitize ruminants (bovids and cervids, but the new species could readily be distinguished from others morphologically. C. longa was more primitive and resembled C. bulboidea, one of the five species from the serow Capricornis crispus, a Japanese member of the Caprinae, and species from Bovidae in Africa. C. crassa had a thick body and large spicules like C. rugosicauda from Capreolus capreolus in Europe, the only previously known Cercopithifilaria species from cervids, but it also had one or two hypertrophied pairs of caudal papillae, an unusual character found so far only in Japanese parasites. Among the 12 species known from ruminants, four are African, one is European and more highly evolved, and seven are Japanese, with some being primitive and some more evolved. The great diversity of Cercopithifilaria species in the two wild ruminants that live in Japan seems to have resulted from local speciation, which occurred during the Pleistocene, from a primitive form of the C. longa type derived from Eurasiatic ancestors, which has disappeared or, more probably, not yet been discovered.

A nuclear DNA-based species determination and DNA quantification assay for common poultry species.

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Ng, J; Satkoski, J; Premasuthan, A; Kanthaswamy, S

2014-12-01

DNA testing for food authentication and quality control requires sensitive species-specific quantification of nuclear DNA from complex and unknown biological sources. We have developed a multiplex assay based on TaqMan® real-time quantitative PCR (qPCR) for species-specific detection and quantification of chicken (Gallus gallus), duck (Anas platyrhynchos), and turkey (Meleagris gallopavo) nuclear DNA. The multiplex assay is able to accurately detect very low quantities of species-specific DNA from single or multispecies sample mixtures; its minimum effective quantification range is 5 to 50 pg of starting DNA material. In addition to its use in food fraudulence cases, we have validated the assay using simulated forensic sample conditions to demonstrate its utility in forensic investigations. Despite treatment with potent inhibitors such as hematin and humic acid, and degradation of template DNA by DNase, the assay was still able to robustly detect and quantify DNA from each of the three poultry species in mixed samples. The efficient species determination and accurate DNA quantification will help reduce fraudulent food labeling and facilitate downstream DNA analysis for genetic identification and traceability.

Genome Sequences of Oryza Species

KAUST Repository

Kumagai, Masahiko

2018-02-14

This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

Genome Sequences of Oryza Species

KAUST Repository

Kumagai, Masahiko; Tanaka, Tsuyoshi; Ohyanagi, Hajime; Hsing, Yue-Ie C.; Itoh, Takeshi

2018-01-01

This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

Species interactions and plant polyploidy.

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Segraves, Kari A; Anneberg, Thomas J

2016-07-01

Polyploidy is a common mode of speciation that can have far-reaching consequences for plant ecology and evolution. Because polyploidy can induce an array of phenotypic changes, there can be cascading effects on interactions with other species. These interactions, in turn, can have reciprocal effects on polyploid plants, potentially impacting their establishment and persistence. Although there is a wealth of information on the genetic and phenotypic effects of polyploidy, the study of species interactions in polyploid plants remains a comparatively young field. Here we reviewed the available evidence for how polyploidy may impact many types of species interactions that range from mutualism to antagonism. Specifically, we focused on three main questions: (1) Does polyploidy directly cause the formation of novel interactions not experienced by diploids, or does it create an opportunity for natural selection to then form novel interactions? (2) Does polyploidy cause consistent, predictable changes in species interactions vs. the evolution of idiosyncratic differences? (3) Does polyploidy lead to greater evolvability in species interactions? From the scarce evidence available, we found that novel interactions are rare but that polyploidy can induce changes in pollinator, herbivore, and pathogen interactions. Although further tests are needed, it is likely that selection following whole-genome duplication is important in all types of species interaction and that there are circumstances in which polyploidy can enhance the evolvability of interactions with other species. © 2016 Botanical Society of America.

Quantifying species recovery and conservation success to develop an IUCN Green List of Species.

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Akçakaya, H Resit; Bennett, Elizabeth L; Brooks, Thomas M; Grace, Molly K; Heath, Anna; Hedges, Simon; Hilton-Taylor, Craig; Hoffmann, Michael; Keith, David A; Long, Barney; Mallon, David P; Meijaard, Erik; Milner-Gulland, E J; Rodrigues, Ana S L; Rodriguez, Jon Paul; Stephenson, P J; Stuart, Simon N; Young, Richard P

2018-03-26

Stopping declines in biodiversity is critically important, but it is only a first step toward achieving more ambitious conservation goals. The absence of an objective and practical definition of species recovery that is applicable across taxonomic groups leads to inconsistent targets in recovery plans and frustrates reporting and maximization of conservation impact. We devised a framework for comprehensively assessing species recovery and conservation success. We propose a definition of a fully recovered species that emphasizes viability, ecological functionality, and representation; and use counterfactual approaches to quantify degree of recovery. This allowed us to calculate a set of 4 conservation metrics that demonstrate impacts of conservation efforts to date (conservation legacy); identify dependence of a species on conservation actions (conservation dependence); quantify expected gains resulting from conservation action in the medium term (conservation gain); and specify requirements to achieve maximum plausible recovery over the long term (recovery potential). These metrics can incentivize the establishment and achievement of ambitious conservation targets. We illustrate their use by applying the framework to a vertebrate, an invertebrate, and a woody and an herbaceous plant. Our approach is a preliminary framework for an International Union for Conservation of Nature (IUCN) Green List of Species, which was mandated by a resolution of IUCN members in 2012. Although there are several challenges in applying our proposed framework to a wide range of species, we believe its further development, implementation, and integration with the IUCN Red List of Threatened Species will help catalyze a positive and ambitious vision for conservation that will drive sustained conservation action. © 2018 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

Phylogeny and species delineation in European species of the genus Steganacarus (Acari, Oribatida) using mitochondrial and nuclear markers.

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Kreipe, Victoria; Corral-Hernández, Elena; Scheu, Stefan; Schaefer, Ina; Maraun, Mark

2015-06-01

Species of the genus Steganacarus are soil-living oribatid mites (Acari, Phthiracaridae) with a ptychoid body. The phylogeny and species status of the species of Steganacarus are not resolved, some authors group all ten German species of Steganacarus within the genus Steganacarus whereas others split them into three subgenera, Steganacarus, Tropacarus and Atropacarus. Additionally, two species, S. magnus and T. carinatus, comprise morphotypes of questionable species status. We investigated the phylogeny and species status of ten European Steganacarus species, i.e. S. applicatus, S. herculeanus, S. magnus forma magna, S. magnus forma anomala, S. spinosus, Tropacarus brevipilus, T. carinatus forma carinata, T. carinatus forma pulcherrima, Atropacarus striculus and Rhacaplacarus ortizi. We used two molecular markers, a 251 bp fragment of the nuclear gene 28S rDNA (D3) and a 477 bp fragment of the mitochondrial COI region. The phylogeny based on a combined analysis of D3 and COI separated four subgenera (Steganacarus, Tropacarus and Atropacarus, Rhacaplacarus) indicating that they form monophyletic groups. The COI region separated all ten species of the genus Steganacarus and showed variation within some species often correlating with the geographic origin of the species. Resolution of the more conserved D3 region was limited, indicating that radiation events are rather recent. Overall, our results indicate that both genes alone cannot be used for phylogeny and barcoding since variation is too low in D3 and too high in COI. However, when used in combination these genes provide reliable insight into the phylogeny, radiation and species status of taxa of the genus Steganacarus.

Aquatic species and habitats

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Danny C. Lee; James R. Sedell; Bruce E. Rieman; Russell F. Thurow; Jack E. Williams

1998-01-01

Continuing human activities threaten the highly prized aquatic resources of the interior Columbia basin. Precipitous declines in native species, particularly Pacific salmon, and a large influx of introduced species have radically altered the composition and distribution of native fishes. Fortunately, areas of relatively high aquatic integrity remain, much of it on...

Cross-species amplification of microsatellite loci developed for Passiflora edulis Sims. in related Passiflora Species

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Gilmara Alvarenga Fachardo Oliveira

2013-10-01

Full Text Available The aim of this study was to evaluate the selected 41 SSR markers developed for yellow passion fruit (Passiflora edulis f. flavicarpa Sims. for their transferability to 11 different Passiflora species. Twenty-one SSR were successfully amplified in 10 wild species of passion fruit producing 101 bands. All the markers were amplifiable for at least one species. The mean transferability was 68,8%, ranging from 15,4% (primer PE11 to 100 % (PE13, PE18, PE37, PE41 and PE88. Transferability was higher for the species from the Passiflora subgenus than for those from the Decaloba and Dysosmia subgenus. The results indicated a high level of nucleotide sequence conservation of the primer regions in the species evaluated, and consequently, they could potentially be used for the establishment of molecular strategies for use in passion fruit breeding and genetics.

Onychiurid species from Wanda Mountains in China, with descriptions of two new species (Collembola, Onychiuridae)

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Sun, Xin; Wu, Donghui

2014-01-01

Abstract A checklist of onychiurid species from the Wanda Mountains in China is presented. Eighteen species belonging to twelve genera have been found, including two new species. Bionychiurus qinglongensis sp. n. can be easily distinguished from other known species of the genus by the absence of pseudocelli on Th. I tergum and fewer number of vesicles in postantennal organ. Onychiurus heilongjiangensis sp. n. is diagnosed by pseudocellar formulae as 32/133/33352 dorsally and 3/011/31120 ventrally, parapseudocellar formula as 0/000/111001+1m, ratio of anal spine/unguis as 0.6, unguiculus without inner basal lamella, and male ventral organ absent. PMID:25147452

'Candidatus Megaira polyxenophila' gen. nov., sp. nov.: considerations on evolutionary history, host range and shift of early divergent rickettsiae.

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Martina Schrallhammer

Full Text Available "Neglected Rickettsiaceae" (i.e. those harboured by non-hematophagous eukaryotic hosts display greater phylogenetic variability and more widespread dispersal than pathogenic ones; yet, the knowledge about their actual host range and host shift mechanism is scarce. The present work reports the characterization following the full-cycle rRNA approach (SSU rRNA sequence, specific in situ hybridization, and ultrastructure of a novel rickettsial bacterium, herewith proposed as 'Candidatus Megaira polyxenophila' gen. nov., sp. nov. We found it in association with four different free-living ciliates (Diophrys oligothrix, Euplotes octocarinatus, Paramecium caudatum, and Spirostomum sp., all belonging to Alveolata, Ciliophora; furthermore it was recently observed as intracellular occurring in Carteria cerasiformis and Pleodorina japonica (Chlorophyceae, Chlorophyta. Phylogenetic analyses demonstrated the belonging of the candidate new genus to the family Rickettsiaceae (Alphaproteobacteria, Rickettsiales as a sister group of the genus Rickettsia. In situ observations revealed the ability of the candidate new species to colonize either nuclear or cytoplasmic compartments, depending on the host organism. The presence of the same bacterial species within different, evolutionary distant, hosts indicates that 'Candidatus Megaira polyxenophila' recently underwent several distinct host shifts, thus suggesting the existence of horizontal transmission pathways. We consider these findings as indicative of an unexpected spread of rickettsial infections in aquatic communities, possibly by means of trophic interactions, and hence propose a new interpretation of the origin and phylogenetic diversification of rickettsial bacteria.

Comparisons of the fungal and protistan communities among different marine sponge holobionts by pyrosequencing.

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He, Liming; Liu, Fang; Karuppiah, Valliappan; Ren, Yi; Li, Zhiyong

2014-05-01

To date, the knowledge of eukaryotic communities associated with sponges remains limited compared with prokaryotic communities. In a manner similar to prokaryotes, it could be hypothesized that sponge holobionts have phylogenetically diverse eukaryotic symbionts, and the eukaryotic community structures in different sponge holobionts were probably different. In order to test this hypothesis, the communities of eukaryota associated with 11 species of South China Sea sponges were compared with the V4 region of 18S ribosomal ribonucleic acid gene using 454 pyrosequencing. Consequently, 135 and 721 unique operational taxonomic units (OTUs) of fungi and protists were obtained at 97 % sequence similarity, respectively. These sequences were assigned to 2 phyla of fungi (Ascomycota and Basidiomycota) and 9 phyla of protists including 5 algal phyla (Chlorophyta, Haptophyta, Streptophyta, Rhodophyta, and Stramenopiles) and 4 protozoal phyla (Alveolata, Cercozoa, Haplosporidia, and Radiolaria) including 47 orders (12 fungi, 35 protists). Entorrhizales of fungi and 18 orders of protists were detected in marine sponges for the first time. Particularly, Tilletiales of fungi and Chlorocystidales of protists were detected for the first time in marine habitats. Though Ascomycota, Alveolata, and Radiolaria were detected in all the 11 sponge species, sponge holobionts have different fungi and protistan communities according to OTU comparison and principal component analysis at the order level. This study provided the first insights into the fungal and protistan communities associated with different marine sponge holobionts using pyrosequencing, thus further extending the knowledge on sponge-associated eukaryotic diversity.

77 FR 30261 - Petition To List 83 Species of Coral as Threatened or Endangered Under the Endangered Species Act...

Science.gov (United States)

2012-05-22

... List 83 Species of Coral as Threatened or Endangered Under the Endangered Species Act (ESA) AGENCY... Diversity (CBD) to list 83 coral species as threatened or endangered under the Endangered Species Act (ESA... the U.S. Endangered Species Act (Status Review Report) and the draft Management Report for 82 Corals...

Is Drosophila-microbe association species-specific or region specific? A study undertaken involving six Indian Drosophila species.

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Singhal, Kopal; Khanna, Radhika; Mohanty, Sujata

2017-06-01

The present work aims to identify the microbial diversity associated with six Indian Drosophila species using next generation sequencing (NGS) technology and to discover the nature of their distribution across species and eco-geographic regions. Whole fly gDNA of six Drosophila species were used to generate sequences in an Illumina platform using NGS technology. De novo based assembled raw reads were blasted against the NR database of NCBI using BLASTn for identification of their bacterial loads. We have tried to include Drosophila species from different taxonomical groups and subgroups and from three different eco-climatic regions India; four species belong to Central India, while the rest two, D. melanogaster and D. ananassae, belong to West and South India to determine both their species-wise and region-wide distribution. We detected the presence of 33 bacterial genera across all six study species, predominated by the class Proteobacteria. Amongst all, D. melanogaster was found to be the most diverse by carrying around 85% of the bacterial diversity. Our findings infer both species-specific and environment-specific nature of the bacterial species inhabiting the Drosophila host. Though the present results are consistent with most of the earlier studies, they also remain incoherent with some. The present study outcome on the host-bacteria association and their species specific adaptation may provide some insight to understand the host-microbial interactions and the phenotypic implications of microbes on the host physiology. The knowledge gained may be importantly applied into the recent insect and pest population control strategy going to implement through gut microflora in India and abroad.

The relationship between species diversity and genetic structure in the rare Picea chihuahuana tree species community, Mexico.

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Simental-Rodríguez, Sergio Leonel; Quiñones-Pérez, Carmen Zulema; Moya, Daniel; Hernández-Tecles, Enrique; López-Sánchez, Carlos Antonio; Wehenkel, Christian

2014-01-01

Species diversity and genetic diversity, the most basic elements of biodiversity, have long been treated as separate topics, although populations evolve within a community context. Recent studies on community genetics and ecology have suggested that genetic diversity is not completely independent of species diversity. The Mexican Picea chihuahuana Martínez is an endemic species listed as "Endangered" on the Red List. Forty populations of Chihuahua spruce have been identified. This species is often associated with tree species of eight genera in gallery forests. This rare Picea chihuahuana tree community covers an area no more than 300 ha and has been subject of several studies involving different topics such as ecology, genetic structure and climate change. The overall aim of these studies was to obtain a dataset for developing management tools to help decision makers implement preservation and conservation strategies. However, this unique forest tree community may also represent an excellent subject for helping us to understand the interplay between ecological and evolutionary processes in determining community structure and dynamics. The AFLP technique and species composition data were used together to test the hypothesis that species diversity is related to the adaptive genetic structure of some dominant tree species (Picea chihuahuana, Pinus strobiformis, Pseudotsuga menziesii and Populus tremuloides) of the Picea chihuahuana tree community at fourteen locations. The Hill numbers were used as a diversity measure. The results revealed a significant correlation between tree species diversity and genetic structure in Populus tremuloides. Because the relationship between the two levels of diversity was found to be positive for the putative adaptive AFLP detected, genetic and species structures of the tree community were possibly simultaneously adapted to a combination of ecological or environmental factors. The present findings indicate that interactions between

Species Typing in Dermal Leishmaniasis

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Dujardin, Jean-Claude

2015-01-01

SUMMARY Leishmania is an infectious protozoan parasite related to African and American trypanosomes. All Leishmania species that are pathogenic to humans can cause dermal disease. When one is confronted with cutaneous leishmaniasis, identification of the causative species is relevant in both clinical and epidemiological studies, case management, and control. This review gives an overview of the currently existing and most used assays for species discrimination, with a critical appraisal of the limitations of each technique. The consensus taxonomy for the genus is outlined, including debatable species designations. Finally, a numerical literature analysis is presented that describes which methods are most used in various countries and regions in the world, and for which purposes. PMID:25672782

Cephalosporium maydis is a distinct species in the Gaeumannomyces-Harpophora species complex.

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Saleh, Amgad A; Leslie, John F

2004-01-01

Cephalosporium maydis is an important plant pathogen whose phylogenetic position relative to other fungi has not been established clearly. We compared strains of C. maydis, strains from several other plant-pathogenic Cephalosporium spp. and several possible relatives within the Gaeumannomyces-Harpophora species complex, to which C. maydis has been suggested to belong based on previous preliminary DNA sequence analyses. DNA sequences of the nuclear genes encoding the rDNA ITS region, β-tubulin, histone H3, and MAT-2 support the hypothesis that C. maydis is a distinct taxon within the Gaeumannomyces-Harpophora species complex. Based on amplified fragment length polymorphism (AFLP) profiles, C. maydis also is distinct from the other tested species of Cephalosporium, Phialophora sensu lato and members of Gaeumannomyces-Harpophora species complex, which supports its classification as Harpophora maydis. Oligonucleotide primers for H. maydis were developed that can be used in a PCR diagnostic protocol to rapidly and reliably detect and identify this pathogen. These diagnostic PCR primers will aid the detection of H. maydis in diseased maize because this fungus can be difficult to detect and isolate, and the movement of authentic cultures may be limited by quarantine restrictions.

An empirical assessment of the focal species hypothesis.

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Lindenmayer, D B; Lane, P W; Westgate, M J; Crane, M; Michael, D; Okada, S; Barton, P S

2014-12-01

Biodiversity surrogates and indicators are commonly used in conservation management. The focal species approach (FSA) is one method for identifying biodiversity surrogates, and it is underpinned by the hypothesis that management aimed at a particular focal species will confer protection on co-occurring species. This concept has been the subject of much debate, in part because the validity of the FSA has not been subject to detailed empirical assessment of the extent to which a given focal species actually co-occurs with other species in an assemblage. To address this knowledge gap, we used large-scale, long-term data sets of temperate woodland birds to select focal species associated with threatening processes such as habitat isolation and loss of key vegetation attributes. We quantified co-occurrence patterns among focal species, species in the wider bird assemblage, and species of conservation concern. Some, but not all, focal species were associated with high levels of species richness. One of our selected focal species was negatively associated with the occurrence of other species (i.e., it was an antisurrogate)-a previously undescribed property of nominated focal species. Furthermore, combinations of focal species were not associated with substantially elevated levels of bird species richness, relative to levels associated with individual species. Our results suggest that although there is some merit to the underpinning concept of the FSA, there is also a need to ensure that actions are sufficiently flexible because management tightly focused on a given focal species may not benefit some other species, including species of conservation concern, such of which might not occur in species-rich assemblages. © 2014 Society for Conservation Biology.

Species composition of a soil invertebrate multi-species test system determines the level of ecotoxicity

International Nuclear Information System (INIS)

Sechi, Valentina; D'Annibale, Alessandra; Maraldo, Kristine; Johansen, Anders; Bossi, Rossana; Jensen, John; Krogh, Paul Henning

2014-01-01

A soil multi-species, SMS, experimental test system consisting of the natural microbial community, five collembolan species and a predatory mite along with either Enchytraeus crypticus or the earthworm Eisenia fetida were exposed to α-cypermethrin. A comparison of the performance of these two types of SMSs is given to aid the development of a standard test system. E. fetida had a positive effect on the majority of the species, reducing the negative insecticide effect. E. fetida affected the species sensitivity and decreased the degradation of the insecticide due to the organic matter incorporation of earthworm food. After 8 weeks, the EC50 was 0.76 mg kg −1 for enchytraeids and ranged between 2.7 and 18.9 mg kg −1 for collembolans, more sensitive than previously observed with single species. Changes observed in the community structure and function illustrates the strength of a multi-species test system as an ecotoxicological tool compared to single species tests. -- Highlights: • Degradation of alpha-cypermethrin was faster with enchytraeids than with earthworms. • Lumbricid castings and bioturbation explains bioavailability of α-cypermethrin. • Pesticide effects on soil arthropods alter with the community composition. • Multispecies test systems are feasible with either an enchytraeid or a lumbricid. • Collembolans are more sensitive to cypermethrin with enchytraeids than with earthworms. -- Soil ecotoxicological fate and effects in multispecies test systems are affected by earthworm activity

Fusarium Species and Their Associated Mycotoxins.

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Munkvold, Gary P

2017-01-01

The genus Fusarium includes numerous toxigenic species that are pathogenic to plants or humans, and are able to colonize a wide range of environments on earth. The genus comprises around 70 well-known species, identified by using a polyphasic approach, and as many as 300 putative species, according to phylogenetic species concepts; many putative species do not yet have formal names. Fusarium is one of the most economically important fungal genera because of yield loss due to plant pathogenic activity; mycotoxin contamination of food and feed products which often render them unaccep for marketing; and health impacts to humans and livestock, due to consumption of mycotoxins. Among the most important mycotoxins produced by species of Fusarium are the trichothecenes and the fumonisins. Fumonisins cause fatal livestock diseases and are considered potentially carcinogenic mycotoxins for humans, while trichothecenes are potent inhibitors of protein synthesis. This chapter summarizes the main aspects of morphology, pathology, and toxigenicity of the main Fusarium species that colonize different agricultural crops and environments worldwide, and cause mycotoxin contamination of food and feed.

Alien species in the Finnish weed flora

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T. HYVÖNEN

2008-12-01

Full Text Available The present study aimed at assessing the invasion of alien weed species in Finland based on a review of their occurrence in the Finnish weed flora. The evaluation was conducted for the three phases of the invasion process, i.e. introduction, naturalization and invasion. The literature review revealed that 815 alien weed species occur in Finland of which 314 are regarded as naturalized. Based on their occurrence in different climate zones, the risk of naturalization of new harmful alien weed species was deemed low for those species not currently found in Finland, but higher for species occurring as casual aliens in Finland. In the latter group, 10 species of concern were detected. Exploration of the distribution patterns of naturalized species within Finland revealed species occupancy to be dependent on the residence time of the species. Established neophytes can be expected to extend their ranges and to increase occupation of agricultural habitats in the future.;

Evaluation of a multiple-species approach to monitoring species at the ecoregional scale

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Patricia N. Manley; William J. Zielinski; Matthew D. Schlesinger; Sylvia R. Mori

2004-01-01

Monitoring is required of land managers and conservation practitioners to assess the success of management actions. "Shortcuts" are sought to reduce monitoring costs, most often consisting of the selection of a small number of species that are closely monitored to represent the status of many associated species and environmental correlates. Assumptions...

Incorporating population viability models into species status assessment and listing decisions under the U.S. Endangered Species Act

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Conor P. McGowan

2017-10-01

Full Text Available Assessment of a species' status is a key part of management decision making for endangered and threatened species under the U.S. Endangered Species Act. Predicting the future state of the species is an essential part of species status assessment, and projection models can play an important role in developing predictions. We built a stochastic simulation model that incorporated parametric and environmental uncertainty to predict the probable future status of the Sonoran desert tortoise in the southwestern United States and North Central Mexico. Sonoran desert tortoise was a Candidate species for listing under the Endangered Species Act, and decision makers wanted to use model predictions in their decision making process. The model accounted for future habitat loss and possible effects of climate change induced droughts to predict future population growth rates, abundances, and quasi-extinction probabilities. Our model predicts that the population will likely decline over the next few decades, but there is very low probability of quasi-extinction less than 75 years into the future. Increases in drought frequency and intensity may increase extinction risk for the species. Our model helped decision makers predict and characterize uncertainty about the future status of the species in their listing decision. We incorporated complex ecological processes (e.g., climate change effects on tortoises in transparent and explicit ways tailored to support decision making processes related to endangered species.

Incorporating population viability models into species status assessment and listing decisions under the U.S. Endangered Species Act

Science.gov (United States)

McGowan, Conor P.; Allan, Nathan; Servoss, Jeff; Hedwall, Shaula J.; Wooldridge, Brian

2017-01-01

Assessment of a species' status is a key part of management decision making for endangered and threatened species under the U.S. Endangered Species Act. Predicting the future state of the species is an essential part of species status assessment, and projection models can play an important role in developing predictions. We built a stochastic simulation model that incorporated parametric and environmental uncertainty to predict the probable future status of the Sonoran desert tortoise in the southwestern United States and North Central Mexico. Sonoran desert tortoise was a Candidate species for listing under the Endangered Species Act, and decision makers wanted to use model predictions in their decision making process. The model accounted for future habitat loss and possible effects of climate change induced droughts to predict future population growth rates, abundances, and quasi-extinction probabilities. Our model predicts that the population will likely decline over the next few decades, but there is very low probability of quasi-extinction less than 75 years into the future. Increases in drought frequency and intensity may increase extinction risk for the species. Our model helped decision makers predict and characterize uncertainty about the future status of the species in their listing decision. We incorporated complex ecological processes (e.g., climate change effects on tortoises) in transparent and explicit ways tailored to support decision making processes related to endangered species.

Species-free species distribution models describe macroecological properties of protected area networks.

Science.gov (United States)

Robinson, Jason L; Fordyce, James A

2017-01-01

Among the greatest challenges facing the conservation of plants and animal species in protected areas are threats from a rapidly changing climate. An altered climate creates both challenges and opportunities for improving the management of protected areas in networks. Increasingly, quantitative tools like species distribution modeling are used to assess the performance of protected areas and predict potential responses to changing climates for groups of species, within a predictive framework. At larger geographic domains and scales, protected area network units have spatial geoclimatic properties that can be described in the gap analysis typically used to measure or aggregate the geographic distributions of species (stacked species distribution models, or S-SDM). We extend the use of species distribution modeling techniques in order to model the climate envelope (or "footprint") of individual protected areas within a network of protected areas distributed across the 48 conterminous United States and managed by the US National Park System. In our approach we treat each protected area as the geographic range of a hypothetical endemic species, then use MaxEnt and 5 uncorrelated BioClim variables to model the geographic distribution of the climatic envelope associated with each protected area unit (modeling the geographic area of park units as the range of a species). We describe the individual and aggregated climate envelopes predicted by a large network of 163 protected areas and briefly illustrate how macroecological measures of geodiversity can be derived from our analysis of the landscape ecological context of protected areas. To estimate trajectories of change in the temporal distribution of climatic features within a protected area network, we projected the climate envelopes of protected areas in current conditions onto a dataset of predicted future climatic conditions. Our results suggest that the climate envelopes of some parks may be locally unique or have

DNA barcoding of shark meats identify species composition and CITES-listed species from the markets in Taiwan.

Science.gov (United States)

Liu, Shang-Yin Vanson; Chan, Chia-Ling Carynn; Lin, Oceana; Hu, Chieh-Shen; Chen, Chaolun Allen

2013-01-01

An increasing awareness of the vulnerability of sharks to exploitation by shark finning has contributed to a growing concern about an unsustainable shark fishery. Taiwan's fleet has the 4th largest shark catch in the world, accounting for almost 6% of the global figures. Revealing the diversity of sharks consumed by Taiwanese is important in designing conservation plans. However, fins make up less than 5% of the total body weight of a shark, and their bodies are sold as filets in the market, making it difficult or impossible to identify species using morphological traits. In the present study, we adopted a DNA barcoding technique using a 391-bp fragment of the mitochondrial cytochrome oxidase I (COI) gene to examine the diversity of shark filets and fins collected from markets and restaurants island-wide in Taiwan. Amongst the 548 tissue samples collected and sequenced, 20 major clusters were apparent by phylogenetic analyses, each of them containing individuals belonging to the same species (most with more than 95% bootstrap values), corresponding to 20 species of sharks. Additionally, Alopias pelagicus, Carcharhinus falciformis, Isurus oxyrinchus, and Prionace glauca consisted of 80% of the samples we collected, indicating that these species might be heavily consumed in Taiwan. Approximately 5% of the tissue samples used in this study were identified as species listed in CITES Appendix II, including two species of Sphyrna, C. longimanus and Carcharodon carcharias. DNA barcoding provides an alternative method for understanding shark species composition when species-specific data is unavailable. Considering the global population decline, stock assessments of Appendix II species and highly consumed species are needed to accomplish the ultimate goal of shark conservation.

A revision of the Australian species of Trimma (Actinopterygii, Gobiidae), with descriptions of six new species and redescriptions of twenty-three valid species.

Science.gov (United States)

Winterbottom, Richard; Hoese, Douglass F

2015-03-17

The gobiid genus Trimma currently contains 75 valid species, with another 20-30 known but undescribed species. There are 29 species in Australian waters (six undescribed). This paper describes the six new species, and provides redescriptions of most of the 23 previously described species known from the region, as well as a key for all the species. The six new species are: T. insularum (endemic to Cocos (Keeling) Islands), T. kitrinum (Fiji to Great Barrier Reef), T. meristum (Cape York to the Bismark Archipelago and Fiji), T. pentherum (Great Barrier Reef to Fiji and the South-West Islands of Palau), T. readerae (Australia to Japan), and T. xanthum (Palau to Fiji, Great Barrier Reef to Christmas Island). The following 23 species have been recorded from Australian waters, and most are redescribed here: T. anaima (Comores to Fiji), T. annosum (Maldives to the Phoenix Islands, Taiwan to the southern Great Barrier Reef), T. benjamini (southern Vietnam to the Marshall Islands, Samoa and southern Barrier Reef), T. caesiura (Ryukyus through the Marshall Islands to Samoa and Elizabeth Reef on the Lord Howe Rise), T. capostriatum (New Caledonia to eastern Australia and Papua New Guinea), T. maiandros (Java to the Ryukyus, Marshalls to Great Barrier Reef), T. emeryi (Comores to Ryukyus and Samoa), T. fangi (western South China Sea through to the Solomons), T. flavatrum (Ryukyu Islands to Western Australia and Samoa), T. hoesei (Chagos Archipelago, central Indian Ocean to Palau and Solomons), T. lantana (Australia, Solomons, northern New Guinea, South-West Islands of Palau), T. macrophthalmus (Ryukyu Islands to Cocos (Keeling) Islands and Samoa), T. milta (Taiwan to Western Australia, Society Islands and Hawaii), T. nasa (Sumbawa, Indonesia to Fiji), T. necopinum (northern tip of Cape York to Sydney), T. nomurai (Japan to northern Australia and New Caledonia), T. okinawae (western Thailand to Japan and the Phoenix Islands, north-west Australia to the Great Barrier Reef), T

The Gilbertiodendron ogoouense species complex (Leguminosae

NARCIS (Netherlands)

Burgt, van der X.M.; Mackinder, B.A.; Wieringa, J.J.; Estrella, de la Manuel

2015-01-01

The Gilbertiodendron ogoouense species complex consists of 14 tree species. Eight species are here newly described and one is here reinstated: G. bambolense Burgt; G. breteleri Burgt; G. ebo Burgt & Mackinder; G. ecoukense (Pellegr.) Burgt; G. maximum Burgt & Wieringa; G. minkebense Burgt

Competition between species of small mammals

International Nuclear Information System (INIS)

Grant, P.R.

1978-01-01

Interspecific competition has often been inferred from its results. In evolutionary time it has been responsible for patterns of regularity in the structure of mammalian communities, and in the morphological and ecological characteristics of the constituent species. In contemporary time it gives rise to reciprocal (complementary) numbers and distributions of two or more species. These inferences are strengthened by recent experimental demonstrations of competition between species of North American rodents. Recent observations and experiments are reviewed. The most thoroughly studied competitors are two species of microtine rodents, Microtus pennsylvanicus and Clethrionomys gapperi. Species which compete for space have been studied experimentally more often than have food competitors. Overt aggression is frequently implicated, but its importance in nature in relation to other means of interaction (e.g. through vocal or scent communication) is not known. The definitive study of competition for food between mammal species has yet to be performed

Radiation protection of non-human species

International Nuclear Information System (INIS)

Leith, I.S.

1993-01-01

The effects of radiation on non-human species, both animals and plants, have long been investigated. In the disposal of radioactive wastes, the protection of non-human species has been investigated. Yet no radiation protection standard for exposure of animals and plants per se has been agreed. The International Commission on Radiological Protection has long taken the view that, if human beings are properly protected from radiation, other species will thereby be protected to the extent necessary for their preservation. However, the International Atomic Energy Agency has found it necessary to investigate the protection of non-human species where radioactivity is released to an environment unpopulated by human beings. It is proposed that the basis of such protection, and the knowledge of radiation effects on non-human species on which it is based, suggest a practical radiation protection standard for non-human species. (1 tab.)

Three new species of tiger beetles and new data on Cicindelina species from Angola (Coleoptera: Carabidae: Cicindelinae).

Science.gov (United States)

Serrano, Artur R M; Capela, Rúben A; Oesterle, Andreas

2015-10-15

Three new species of tiger beetles, two of the genus Trichotaenia Rivalier, 1957 and one of the genus Cylindera Westwood, 1831, subgenus Ifasina Jeannel, 1946 are described from Angola. An annotated list of species of Cicindelina sampled in this country is provided also. Records for three species previously unknow from Angola are given: Ophryodera smrzi Werner, 2005, Lophyra clatharta (Dejean, 1825) and Lophyra sumlini Cassola, 1976. Some considerations on the distribution and general ecology of these beetles in Angola are also presented. Further, two dichotomic keys are made available for the identification of Trichotaenia species with marked shoulders and Cylindera (Ifasina) species of western and southwestern Africa, respectively.

Theoretical microbial ecology without species

Science.gov (United States)

Tikhonov, Mikhail

2017-09-01

Ecosystems are commonly conceptualized as networks of interacting species. However, partitioning natural diversity of organisms into discrete units is notoriously problematic and mounting experimental evidence raises the intriguing question whether this perspective is appropriate for the microbial world. Here an alternative formalism is proposed that does not require postulating the existence of species as fundamental ecological variables and provides a naturally hierarchical description of community dynamics. This formalism allows approaching the species problem from the opposite direction. While the classical models treat a world of imperfectly clustered organism types as a perturbation around well-clustered species, the presented approach allows gradually adding structure to a fully disordered background. The relevance of this theoretical construct for describing highly diverse natural ecosystems is discussed.

Effect of species rarity on the accuracy of species distribution models for reptiles and amphibians in southern California

Science.gov (United States)

Franklin, J.; Wejnert, K.E.; Hathaway, S.A.; Rochester, C.J.; Fisher, R.N.

2009-01-01

Aim: Several studies have found that more accurate predictive models of species' occurrences can be developed for rarer species; however, one recent study found the relationship between range size and model performance to be an artefact of sample prevalence, that is, the proportion of presence versus absence observations in the data used to train the model. We examined the effect of model type, species rarity class, species' survey frequency, detectability and manipulated sample prevalence on the accuracy of distribution models developed for 30 reptile and amphibian species. Location: Coastal southern California, USA. Methods: Classification trees, generalized additive models and generalized linear models were developed using species presence and absence data from 420 locations. Model performance was measured using sensitivity, specificity and the area under the curve (AUC) of the receiver-operating characteristic (ROC) plot based on twofold cross-validation, or on bootstrapping. Predictors included climate, terrain, soil and vegetation variables. Species were assigned to rarity classes by experts. The data were sampled to generate subsets with varying ratios of presences and absences to test for the effect of sample prevalence. Join count statistics were used to characterize spatial dependence in the prediction errors. Results: Species in classes with higher rarity were more accurately predicted than common species, and this effect was independent of sample prevalence. Although positive spatial autocorrelation remained in the prediction errors, it was weaker than was observed in the species occurrence data. The differences in accuracy among model types were slight. Main conclusions: Using a variety of modelling methods, more accurate species distribution models were developed for rarer than for more common species. This was presumably because it is difficult to discriminate suitable from unsuitable habitat for habitat generalists, and not as an artefact of the

Discordance between morphological and molecular species boundaries among Caribbean species of the reef sponge Callyspongia

OpenAIRE

DeBiasse, Melissa B; Hellberg, Michael E

2015-01-01

Sponges are among the most species-rich and ecologically important taxa on coral reefs, yet documenting their diversity is difficult due to the simplicity and plasticity of their morphological characters. Genetic attempts to identify species are hampered by the slow rate of mitochondrial sequence evolution characteristic of sponges and some other basal metazoans. Here we determine species boundaries of the Caribbean coral reef sponge genus Callyspongia using a multilocus, model-based approach...

50 CFR 451.03 - Endangered Species Committee.

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Endangered Species Committee. 451.03... ADMINISTRATION, DEPARTMENT OF COMMERCE); ENDANGERED SPECIES COMMITTEE REGULATIONS ENDANGERED SPECIES EXEMPTION PROCESS APPLICATION PROCEDURE § 451.03 Endangered Species Committee. (a) Scope. This section contains...

Species coexistence in a changing world.

Science.gov (United States)

Valladares, Fernando; Bastias, Cristina C; Godoy, Oscar; Granda, Elena; Escudero, Adrián

2015-01-01

The consequences of global change for the maintenance of species diversity will depend on the sum of each species responses to the environment and on the interactions among them. A wide ecological literature supports that these species-specific responses can arise from factors related to life strategies, evolutionary history and intraspecific variation, and also from environmental variation in space and time. In the light of recent advances from coexistence theory combined with mechanistic explanations of diversity maintenance, we discuss how global change drivers can influence species coexistence. We revise the importance of both competition and facilitation for understanding coexistence in different ecosystems, address the influence of phylogenetic relatedness, functional traits, phenotypic plasticity and intraspecific variability, and discuss lessons learnt from invasion ecology. While most previous studies have focused their efforts on disentangling the mechanisms that maintain the biological diversity in species-rich ecosystems such as tropical forests, grasslands and coral reefs, we argue that much can be learnt from pauci-specific communities where functional variability within each species, together with demographic and stochastic processes becomes key to understand species interactions and eventually community responses to global change.

Design and construction of "synthetic species".

Directory of Open Access Journals (Sweden)

Eduardo Moreno

Full Text Available Synthetic biology is an area of biological research that combines science and engineering. Here, I merge the principles of synthetic biology and regulatory evolution to create a new species with a minimal set of known elements. Using preexisting transgenes and recessive mutations of Drosophila melanogaster, a transgenic population arises with small eyes and a different venation pattern that fulfils the criteria of a new species according to Mayr's Biological Species Concept. The population described here is the first transgenic organism that cannot hybridize with the original wild type population but remains fertile when crossed with other identical transgenic animals. I therefore propose the term "synthetic species" to distinguish it from "natural species", not only because it has been created by genetic manipulation, but also because it may never be able to survive outside the laboratory environment. The use of genetic engineering to design artificial species barriers could help us understand natural speciation and may have practical applications. For instance, the transition from transgenic organisms towards synthetic species could constitute a safety mechanism to avoid the hybridization of genetically modified animals with wild type populations, preserving biodiversity.

New species of Cystolepiota from China

Directory of Open Access Journals (Sweden)

Meng-Lin Xu

2016-10-01

Full Text Available In this paper, a new species, Cystolepiota pseudofumosifolia, is introduced. C. pseudofumosifolia is characterized by granulose or powdery pileus with an anatomic structure that is loosely globose, as well as ellipsoid cells in chains in the pileus covering the cheilocystidia. This new species is compared to the related and similar Cystolepiota species in morphology and molecular phylogeny based on Internal transcribed spacer sequences. Both types of data support our specimens as a new species in the genus Cystolepiota.

Brachyspira Species and Gastroenteritis in Humans

NARCIS (Netherlands)

Westerman, L.J.; Boer, de R.F.; Roelfsema, J.H.; Friesema, I.H.M.; Kortbeek, L.M.; Wagenaar, J.A.; Bonten, M.J.M.; Kusters, J.G.

2013-01-01

Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were

Brachyspira Species and Gastroenteritis in Humans

NARCIS (Netherlands)

Westerman, L J; de Boer, R F; Roelfsema, J H; Friesema, I H M; Kortbeek, L M; Wagenaar, J A; Bonten, M J M; Kusters, J G

Brachyspira species have been implicated as a potential cause of gastroenteritis in humans; this is, however, controversial. In 733 gastroenteritis cases and 464 controls, we found 29 samples positive for Brachyspira species (2.3% of cases and 2.6% of controls; P = 0.77). Brachyspira species were

77 FR 15701 - Highly Migratory Species; 2006 Consolidated Highly Migratory Species Fishery Management Plan...

Science.gov (United States)

2012-03-16

... Species Fishery Management Plan; Amendment 4 AGENCY: National Marine Fisheries Service (NMFS), National.... SUMMARY: This fishery management plan (FMP) amendment addresses Atlantic highly migratory species (HMS... to create an HMS Caribbean Small Boat Commercial Permit (CSBP) allowing fishing for and sales of...

Endangered Species Act Critical Habitat

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

Aging and immortality in unicellular species.

Science.gov (United States)

Florea, Michael

2017-10-01

It has been historically thought that in conditions that permit growth, most unicellular species do not to age. This was particularly thought to be the case for symmetrically dividing species, as such species lack a clear distinction between the soma and the germline. Despite this, studies of the symmetrically dividing species Escherichia coli and Schizosaccharomyces pombe have recently started to challenge this notion. They indicate that E. coli and S. pombe do age, but only when subjected to environmental stress. If true, this suggests that aging may be widespread among microbial species in general, and that studying aging in microbes may inform other long-standing questions in aging. This review examines the recent evidence for and against replicative aging in symmetrically dividing unicellular organisms, the mechanisms that underlie aging, why aging evolved in these species, and how microbial aging fits into the context of other questions in aging. Copyright © 2017 Elsevier B.V. All rights reserved.

DNA barcoding of shark meats identify species composition and CITES-listed species from the markets in Taiwan.

Directory of Open Access Journals (Sweden)

Shang-Yin Vanson Liu

Full Text Available BACKGROUND: An increasing awareness of the vulnerability of sharks to exploitation by shark finning has contributed to a growing concern about an unsustainable shark fishery. Taiwan's fleet has the 4th largest shark catch in the world, accounting for almost 6% of the global figures. Revealing the diversity of sharks consumed by Taiwanese is important in designing conservation plans. However, fins make up less than 5% of the total body weight of a shark, and their bodies are sold as filets in the market, making it difficult or impossible to identify species using morphological traits. METHODS: In the present study, we adopted a DNA barcoding technique using a 391-bp fragment of the mitochondrial cytochrome oxidase I (COI gene to examine the diversity of shark filets and fins collected from markets and restaurants island-wide in Taiwan. RESULTS: Amongst the 548 tissue samples collected and sequenced, 20 major clusters were apparent by phylogenetic analyses, each of them containing individuals belonging to the same species (most with more than 95% bootstrap values, corresponding to 20 species of sharks. Additionally, Alopias pelagicus, Carcharhinus falciformis, Isurus oxyrinchus, and Prionace glauca consisted of 80% of the samples we collected, indicating that these species might be heavily consumed in Taiwan. Approximately 5% of the tissue samples used in this study were identified as species listed in CITES Appendix II, including two species of Sphyrna, C. longimanus and Carcharodon carcharias. CONCLUSION: DNA barcoding provides an alternative method for understanding shark species composition when species-specific data is unavailable. Considering the global population decline, stock assessments of Appendix II species and highly consumed species are needed to accomplish the ultimate goal of shark conservation.

22 CFR 216.5 - Endangered species.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Endangered species. 216.5 Section 216.5 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ENVIRONMENTAL PROCEDURES § 216.5 Endangered species. It is A... endangered or threatened species and their critical habitats. The Initial Environmental Examination for each...

The Colletotrichum gloeosporioides species complex.

Science.gov (United States)

Weir, B S; Johnston, P R; Damm, U

2012-09-15

The limit of the Colletotrichum gloeosporioides species complex is defined genetically, based on a strongly supported clade within the Colletotrichum ITS gene tree. All taxa accepted within this clade are morphologically more or less typical of the broadly defined C. gloeosporioides, as it has been applied in the literature for the past 50 years. We accept 22 species plus one subspecies within the C. gloeosporioides complex. These include C. asianum, C. cordylinicola, C. fructicola, C. gloeosporioides, C. horii, C. kahawae subsp. kahawae, C. musae, C. nupharicola, C. psidii, C. siamense, C. theobromicola, C. tropicale, and C. xanthorrhoeae, along with the taxa described here as new, C. aenigma, C. aeschynomenes, C. alatae, C. alienum, C. aotearoa, C. clidemiae, C. kahawae subsp. ciggaro, C. salsolae, and C. ti, plus the nom. nov. C. queenslandicum (for C. gloeosporioides var. minus). All of the taxa are defined genetically on the basis of multi-gene phylogenies. Brief morphological descriptions are provided for species where no modern description is available. Many of the species are unable to be reliably distinguished using ITS, the official barcoding gene for fungi. Particularly problematic are a set of species genetically close to C. musae and another set of species genetically close to C. kahawae, referred to here as the Musae clade and the Kahawae clade, respectively. Each clade contains several species that are phylogenetically well supported in multi-gene analyses, but within the clades branch lengths are short because of the small number of phylogenetically informative characters, and in a few cases individual gene trees are incongruent. Some single genes or combinations of genes, such as glyceraldehyde-3-phosphate dehydrogenase and glutamine synthetase, can be used to reliably distinguish most taxa and will need to be developed as secondary barcodes for species level identification, which is important because many of these fungi are of biosecurity

Microbial species delineation using whole genome sequences.

Science.gov (United States)

Varghese, Neha J; Mukherjee, Supratim; Ivanova, Natalia; Konstantinidis, Konstantinos T; Mavrommatis, Kostas; Kyrpides, Nikos C; Pati, Amrita

2015-08-18

Increased sequencing of microbial genomes has revealed that prevailing prokaryotic species assignments can be inconsistent with whole genome information for a significant number of species. The long-standing need for a systematic and scalable species assignment technique can be met by the genome-wide Average Nucleotide Identity (gANI) metric, which is widely acknowledged as a robust measure of genomic relatedness. In this work, we demonstrate that the combination of gANI and the alignment fraction (AF) between two genomes accurately reflects their genomic relatedness. We introduce an efficient implementation of AF,gANI and discuss its successful application to 86.5M genome pairs between 13,151 prokaryotic genomes assigned to 3032 species. Subsequently, by comparing the genome clusters obtained from complete linkage clustering of these pairs to existing taxonomy, we observed that nearly 18% of all prokaryotic species suffer from anomalies in species definition. Our results can be used to explore central questions such as whether microorganisms form a continuum of genetic diversity or distinct species represented by distinct genetic signatures. We propose that this precise and objective AF,gANI-based species definition: the MiSI (Microbial Species Identifier) method, be used to address previous inconsistencies in species classification and as the primary guide for new taxonomic species assignment, supplemented by the traditional polyphasic approach, as required. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Two new Paraparatrechina (Hymenoptera, Formicidae species from the Seychelles, with notes on the hypogaeic weissi species-group

Directory of Open Access Journals (Sweden)

John LaPolla

2014-06-01

Full Text Available Recent survey work in the Seychelles has revealed two new species of Paraparatrechina that are here described: P. illusio sp. n. and P. luminella sp. n. A revised key to the workers of Paraparatrechina for the Afrotropical and Malagasy regions is provided. The taxonomy of the hypogaeic weissi species-group is also reviewed in light of recent field collections. The species P. sordida is revived from synonymy and given new status (as a full species and a discussion of the morphologically peculiar species-group is provided. With the description of the two species and the removal of another species from weissi synonomy there are now 16 Paraparatrechina species known from the Afrotropical and Malagasy regions.

77 FR 19164 - Atlantic Highly Migratory Species; 2006 Consolidated Highly Migratory Species Fishery Management...

Science.gov (United States)

2012-03-30

... RIN 0648-XB121 Atlantic Highly Migratory Species; 2006 Consolidated Highly Migratory Species Fishery..., United States Virgin Islands (USVI) St. Thomas, USVI, San Juan, Puerto Rico (PR), Ponce, PR, and Mayaguez... INFORMATION CONTACT: Greg Fairclough or Randy Blankinship at 727-824-5399. SUPPLEMENTARY INFORMATION: Atlantic...

Species status and conservation issues of New Zealand's endemic Latrodectus spider species (Araneae: Theridiidae)

DEFF Research Database (Denmark)

Vink, Cor J; Sirvid, Phillip J; Malumbres-Olarte, Jagoba

2008-01-01

New Zealand has two endemic widow spiders, Latrodectus katipo Powell, 1871 and L. atritus Urquhart, 1890. Both species face many conservation threats and are actively managed. The species status of the Latrodectus spiders of New Zealand was assessed using molecular (COI, ITS1, ITS2...

The species velocity of trees in Alaska

Science.gov (United States)

Morrison, B. D.; Napier, J.; de Lafontaine, G.; Heath, K.; Li, B.; Hu, F.; Greenberg, J. A.

2017-12-01

Anthropogenic climate change has motivated interest in the paleo record to enhance our knowledge about past vegetation responses to climate change and help understand potential responses in the future. Additionally, polar regions currently experience the most rapid rates of climate change globally, prompting concern over changes in the ecological composition of high latitude ecosystems. Recent analyses have attempted to construct methods to estimate a species' ability to track climate change by computing climate velocity; a measure of the rate of climate displacement across a landscape which may indicate the speed an organism must migrate to keep pace with climate change. However, a challenge to using climate velocity in understanding range shifts is a lack of species-specificity in the velocity calculations: climate velocity does not actually use any species data in its analysis. To solve the shortcomings of climate velocity in estimating species displacement rates, we computed the "species velocity" of white spruce, green and grey alder populations across the state of Alaska from the Last Glacial Maximum (LGM) to today. Species velocity represents the rate and direction a species is required to migrate to keep pace with a changing climate following the LGM. We used a species distribution model to determine past and present white spruce and alder distributions using statistically downscaled climate data at 60m. Species velocity was then derived from the change in species distribution per year by the change in distribution over Alaska (km/yr). High velocities indicate locations where the species environmental envelope is changing drastically and must disperse rapidly to survive climate change. As a result, high velocity regions are more vulnerable to distribution shifts and higher risk of local extinction. Conversely, low species velocities indicate locations where the local climate envelope is shifting relatively slowly, reducing the stress to disperse quickly

Phytoprotective effect of arbuscular mycorrhizal fungi species against arsenic toxicity in tropical leguminous species.

Science.gov (United States)

de Melo, Rangel Wesley; Schneider, Jerusa; de Souza, Costa Enio Tarso; Sousa, Soares Cláudio Roberto Fonsêca; Guimarães, Guilherme Luiz Roberto; de Souza, Moreira Fatima Maria

2014-01-01

Arbuscular mycorrhizal fungi (AMF) improve the tolerance of hosting plants to arsenic (As) in contaminated soils. This work assessed the phytoprotective effect of Glomus etunicatum, Acaulospora morrowiae, Gigaspora gigantea, and Acaulospora sp. on four leguminous species (Acacia mangium, Crotalaria juncea, Enterolobium contortisiliquum, and Stizolobium aterrimum) in an As-contaminated soil from a gold mining area. AMF root colonization, biomass production, As and P accumulation, as well as arsenic translocation index (TI) from roots to shoots were measured. The AMF phytoprotective effect was assessed by the P/As ratio and the activity of plant antioxidant enzymes. The AMF colonization ranged from 24 to 28%. In general, all leguminous species had low As TI when inoculated with AMF species. Inoculation of C. juncea with Acaulospora sp. improved significantly As accumulation in roots, and decreased the activity of ascorbate peroxidase (APX) and superoxide dismutase (SOD), highlighting its phytoprotective effect and the potential use of this symbiosis for phytoremediation of As-contaminated soils. However, S. aterrimum has also shown a potential for phytoremediation irrespectively of AMF inoculation. APX was a good indicator of the phytoprotective effect against As contamination in C. juncea and A. mangium. In general P/As ratio in shoots was the best indicator of the phytoprotective effect of all AMF species in all plant species.

SALMONELLA SPECIES

African Journals Online (AJOL)

DR. AMINU

... of Salmonella species serotypes in relation to age and sex among children, ..... However, most antimicrobials show sufficient selective toxicity to be of value in ... salmonellosis should be given good attention (Barrow et al., 2007). To reduce ...

50 CFR 15.32 - Criteria for including species in the approved list for non-captive-bred species.

Science.gov (United States)

2010-10-01

... Management and Scientific Authorities transmitting the management plan of this species; (iii) A summary of... where the species forages (aerial feeder, tree canopy, tree trunk, midstory, understory, open water or..., disease carrier; a description of the damage the pest species causes to its ecosystem; and a description...

3 CFR - The Endangered Species Act

Science.gov (United States)

2010-01-01

... 3 The President 1 2010-01-01 2010-01-01 false The Endangered Species Act Presidential Documents Other Presidential Documents Memorandum of March 3, 2009 The Endangered Species Act Memorandum for the Heads of Executive Departments and Agencies The Endangered Species Act (ESA), 16 U.S.C. 1531 et seq...

Aquatic dance flies (Diptera, Empididae, Clinocerinae and Hemerodromiinae of Greece: species richness, distribution and description of five new species

Directory of Open Access Journals (Sweden)

Marija Ivković

2017-12-01

Full Text Available All records of aquatic dance flies (37 species in subfamily Clinocerinae and 10 species in subfamily Hemerodromiinae from the territory of Greece are summarized, including previously unpublished data and data on five newly described species (Chelifera horvati Ivković & Sinclair, sp. n., Wiedemannia iphigeniae Ivković & Sinclair, sp. n., W. ljerkae Ivković & Sinclair, sp. n., W. nebulosa Ivković & Sinclair, sp. n. and W. pseudoberthelemyi Ivković & Sinclair, sp. n.. The new species are described and illustrated, the male terminalia of Clinocera megalatlantica (Vaillant are illustrated and the distributions of all species within Greece are listed. The aquatic Empididae fauna of Greece consists of 47 species, with the following described species reported for the first time: Chelifera angusta Collin, Hemerodromia melangyna Collin, Clinocera megalatlantica, Kowarzia plectrum (Mik, Phaeobalia dimidiata (Loew, W. (Chamaedipsia beckeri (Mik, W. (Philolutra angelieri Vaillant and W. (P. chvali Joost. A key to species of aquatic Empididae of Greece is provided for the first time. Information related to the European Ecoregions in which species were found is given. Compared to the other studied countries in the Balkans, the Greek species assemblage is most similar to that of the Former Yugoslav Republic of Macedonia.

Occurrence of genus Monostroma (Ulvales, Chlorophyta) from Ratnagiri (Maharashtra)

Digital Repository Service at National Institute of Oceanography (India)

Untawale, A; Agadi, V.V.; Dhargalkar, V.K.

The occurrence of a genus Monostroma has been recorded from the Shirgaon creek at Ratnagiri along the central west coast of India. The Monostroma sp. was found in the brackish water environment with low salinity, high nutrients and thick mangrove...

Clonal growth and plant species abundance.

Science.gov (United States)

Herben, Tomáš; Nováková, Zuzana; Klimešová, Jitka

2014-08-01

Both regional and local plant abundances are driven by species' dispersal capacities and their abilities to exploit new habitats and persist there. These processes are affected by clonal growth, which is difficult to evaluate and compare across large numbers of species. This study assessed the influence of clonal reproduction on local and regional abundances of a large set of species and compared the predictive power of morphologically defined traits of clonal growth with data on actual clonal growth from a botanical garden. The role of clonal growth was compared with the effects of seed reproduction, habitat requirements and growth, proxied both by LHS (leaf-height-seed) traits and by actual performance in the botanical garden. Morphological parameters of clonal growth, actual clonal reproduction in the garden and LHS traits (leaf-specific area - height - seed mass) were used as predictors of species abundance, both regional (number of species records in the Czech Republic) and local (mean species cover in vegetation records) for 836 perennial herbaceous species. Species differences in habitat requirements were accounted for by classifying the dataset by habitat type and also by using Ellenberg indicator values as covariates. After habitat differences were accounted for, clonal growth parameters explained an important part of variation in species abundance, both at regional and at local levels. At both levels, both greater vegetative growth in cultivation and greater lateral expansion trait values were correlated with higher abundance. Seed reproduction had weaker effects, being positive at the regional level and negative at the local level. Morphologically defined traits are predictive of species abundance, and it is concluded that simultaneous investigation of several such traits can help develop hypotheses on specific processes (e.g. avoidance of self-competition, support of offspring) potentially underlying clonal growth effects on abundance. Garden

Conservation Status of Marine Biodiversity in Oceania: An Analysis of Marine Species on the IUCN Red List of Threatened Species

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Beth A. Polidoro

2011-01-01

Full Text Available Given the economic and cultural dependence on the marine environment in Oceania and a rapidly expanding human population, many marine species populations are in decline and may be vulnerable to extinction from a number of local and regional threats. IUCN Red List assessments, a widely used system for quantifying threats to species and assessing species extinction risk, have been completed for 1190 marine species in Oceania to date, including all known species of corals, mangroves, seagrasses, sea snakes, marine mammals, sea birds, sea turtles, sharks, and rays present in Oceania, plus all species in five important perciform fish groups. Many of the species in these groups are threatened by the modification or destruction of coastal habitats, overfishing from direct or indirect exploitation, pollution, and other ecological or environmental changes associated with climate change. Spatial analyses of threatened species highlight priority areas for both site- and species-specific conservation action. Although increased knowledge and use of newly available IUCN Red List assessments for marine species can greatly improve conservation priorities for marine species in Oceania, many important fish groups are still in urgent need of assessment.

Novel Bartonella Species in Insectivorous Bats, Northern China.

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Hui-Ju Han

Full Text Available Bartonella species are emerging human pathogens. Bats are known to carry diverse Bartonella species, some of which are capable of infecting humans. However, as the second largest mammalian group by a number of species, the role of bats as the reservoirs of Bartonella species is not fully explored, in term of their species diversity and worldwide distribution. China, especially Northern China, harbors a number of endemic insectivorous bat species; however, to our knowledge, there are not yet studies about Bartonella in bats in China. The aim of the study was to investigate the prevalence and genetic diversity of Bartonella species in bats in Northern China. Bartonella species were detected by PCR amplification of gltA gene in 25.2% (27/107 bats in Mengyin County, Shandong Province of China, including 1/3 Rhinolophus ferrumequinum, 2/10 Rhinolophus pusillus, 9/16 Myotis fimbriatus, 1/5 Myotis ricketti, 14/58 Myotis pequinius. Phylogenetic analysis showed that Bartonella species detected in bats in this study clustered into ten groups, and some might be novel Bartonella species. An association between Bartonella species and bat species was demonstrated and co-infection with different Bartonella species in a single bat was also observed. Our findings expanded our knowledge on the genetic diversity of Bartonella in bats, and shed light on the ecology of bat-borne Bartonella species.

32 CFR 643.32 - Policy-Endangered species.

Science.gov (United States)

2010-07-01

... ESTATE Policy § 643.32 Policy—Endangered species. The Endangered Species Act of 1973 (16 U.S.C. 1531 et seq.), declares the intention of Congress to conserve threatened and endangered species of fish... 32 National Defense 4 2010-07-01 2010-07-01 true Policy-Endangered species. 643.32 Section 643.32...

Malassezia Species and Pityriasis Versicolor

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Gulin Rodoplu

2016-01-01

Full Text Available Malassezia species are found in part of the normal human cutaneous commensal flora, however it has been known for many years that the Malassezia yeasts are associated with a number of different human diseases ranging from pityriasis versicolor to seborrhoeic dermatitis. In addition, since the 1980s, they have been reported as causing opportunistic systemic infections. The taxonomy of Malassezia spp. has recently been modified to include 13 obligatorily lipophilic species, plus one non-obligatorily lipophilic species, which only rarely colonizes human hosts and currently the genus consist 14 species as M. furfur, M. pachydermatis, M. sympodialis, M. globosa, M. obtusa, M. slooffiae, M. restricta, M. dermatis, M. japonica, M. nana, M. yamatoensis, M. caprae, M. equina, M. cuniculi. Fastidious growth requirements of Malassezia yeasts defied the initial attempts to culture these organisms and their true identification and the relationship between different species only became apparent with the application of modern molecular techniques. The causative fungus is seen especially in such seborrheic areas as the scalp, face, trunk and upper back. Under the influence of various exogenous or endogenous predisposing factors, these yeasts change from the blastospore form to the mycelial form and become pathogenic. Diagnosis of pityriasis versicolor which is caused by Malassezia species is generally easy and lies on the basis of its clinical appearance and can be confirmed by mycological examination. The diagnosisis is mainly based on direct examination with potassium hydroxide (KOH and demonstration that represents pseudohyphae and blastoconidia as the typical %u201Cspaghetti and meatballs%u201D pattern. Characteristic features of the genus Malassezia include a distinctive morphology and an affinity for lipids in culture. Culture is necessary to recover the infecting strain, especially for epidemiologic purposes and also to test its antifungal susceptibility

77 FR 22749 - Petition To List 83 Species of Coral as Threatened or Endangered Under the Endangered Species Act...

Science.gov (United States)

2012-04-17

... threatened or endangered under the Endangered Species Act (ESA) and to notify the public about future public... Candidate Coral Species Petitioned Under the U.S. Endangered Species Act (Status Review Report) and the draft Management Report for 82 Corals Status Review under the Endangered Species Act: Assessment of...

New species in Aspergillus section Terrei

DEFF Research Database (Denmark)

Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian

2011-01-01

. clade including the type isolate of A. niveus (CBS 115.27) constitutes a lineage closely related to A. carneus. Fennellia nivea, the hypothesized teleomorph is not related to this clade. Aspergillus allahabadii, A. niveus var. indicus, and two species originally placed in section Versicolores, A......Section Terrei of Aspergillus was studied using a polyphasic approach including sequence analysis of parts of the beta-tubulin and calmodulin genes and the ITS region, macro- and micromorphological analyses and examination of extrolite profiles to describe three new species in this section. Based....... floccosus, A. terreus var. africanus, A. terreus var. aureus, while Aspergillus hortai is recognised at species level. Aspergillus terreus NRRL 4017 is described as the new species A. pseudoterreus. Also included in section Terrei are some species formerly placed in sections Flavipedes and Versicolores. A...

New species of Malaysian ferns

NARCIS (Netherlands)

Holttum, R.E.

1962-01-01

The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

Phylogenetic Molecular Species Delimitations Unravel Potential New Species in the Pest Genus Spodoptera Guenée, 1852 (Lepidoptera, Noctuidae)

Science.gov (United States)

Dumas, Pascaline; Barbut, Jérôme; Le Ru, Bruno; Silvain, Jean-François; Clamens, Anne-Laure; d’Alençon, Emmanuelle; Kergoat, Gael J.

2015-01-01

Nowadays molecular species delimitation methods promote the identification of species boundaries within complex taxonomic groups by adopting innovative species concepts and theories (e.g. branching patterns, coalescence). As some of them can efficiently deal with large single-locus datasets, they could speed up the process of species discovery compared to more time consuming molecular methods, and benefit from the existence of large public datasets; these methods can also particularly favour scientific research and actions dealing with threatened or economically important taxa. In this study we aim to investigate and clarify the status of economically important moths species belonging to the genus Spodoptera (Lepidoptera, Noctuidae), a complex group in which previous phylogenetic analyses and integrative approaches already suggested the possible occurrence of cryptic species and taxonomic ambiguities. In this work, the effectiveness of innovative (and faster) species delimitation approaches to infer putative species boundaries has been successfully tested in Spodoptera, by processing the most comprehensive dataset (in terms of number of species and specimens) ever achieved; results are congruent and reliable, irrespective of the set of parameters and phylogenetic models applied. Our analyses confirm the existence of three potential new species clusters (for S. exigua (Hübner, 1808), S. frugiperda (J.E. Smith, 1797) and S. mauritia (Boisduval, 1833)) and support the synonymy of S. marima (Schaus, 1904) with S. ornithogalli (Guenée, 1852). They also highlight the ambiguity of the status of S. cosmiodes (Walker, 1858) and S. descoinsi Lalanne-Cassou & Silvain, 1994. This case study highlights the interest of molecular species delimitation methods as valuable tools for species discovery and to emphasize taxonomic ambiguities. PMID:25853412

Phylogenetic molecular species delimitations unravel potential new species in the pest genus Spodoptera Guenée, 1852 (Lepidoptera, Noctuidae.

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Pascaline Dumas

Full Text Available Nowadays molecular species delimitation methods promote the identification of species boundaries within complex taxonomic groups by adopting innovative species concepts and theories (e.g. branching patterns, coalescence. As some of them can efficiently deal with large single-locus datasets, they could speed up the process of species discovery compared to more time consuming molecular methods, and benefit from the existence of large public datasets; these methods can also particularly favour scientific research and actions dealing with threatened or economically important taxa. In this study we aim to investigate and clarify the status of economically important moths species belonging to the genus Spodoptera (Lepidoptera, Noctuidae, a complex group in which previous phylogenetic analyses and integrative approaches already suggested the possible occurrence of cryptic species and taxonomic ambiguities. In this work, the effectiveness of innovative (and faster species delimitation approaches to infer putative species boundaries has been successfully tested in Spodoptera, by processing the most comprehensive dataset (in terms of number of species and specimens ever achieved; results are congruent and reliable, irrespective of the set of parameters and phylogenetic models applied. Our analyses confirm the existence of three potential new species clusters (for S. exigua (Hübner, 1808, S. frugiperda (J.E. Smith, 1797 and S. mauritia (Boisduval, 1833 and support the synonymy of S. marima (Schaus, 1904 with S. ornithogalli (Guenée, 1852. They also highlight the ambiguity of the status of S. cosmiodes (Walker, 1858 and S. descoinsi Lalanne-Cassou & Silvain, 1994. This case study highlights the interest of molecular species delimitation methods as valuable tools for species discovery and to emphasize taxonomic ambiguities.

The Candida Pathogenic Species Complex

Science.gov (United States)

Turner, Siobhán A.; Butler, Geraldine

2014-01-01

Candida species are the most common causes of fungal infection. Approximately 90% of infections are caused by five species: Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei. Three (C. albicans, C. tropicalis, and C. parapsilosis) belong to the CTG clade, in which the CTG codon is translated as serine and not leucine. C. albicans remains the most commonly isolated but is decreasing relative to the other species. The increasing incidence of C. glabrata is related to its reduced susceptibility to azole drugs. Genome analysis suggests that virulence in the CTG clade is associated with expansion of gene families, particularly of cell wall genes. Similar independent processes took place in the C. glabrata species group. Gene loss and expansion in an ancestor of C. glabrata may have resulted in preadaptations that enabled pathogenicity. PMID:25183855

Review: Allee effects in social species.

Science.gov (United States)

Angulo, Elena; Luque, Gloria M; Gregory, Stephen D; Wenzel, John W; Bessa-Gomes, Carmen; Berec, Ludek; Courchamp, Franck

2018-01-01

Allee effects have important implications for many aspects of basic and applied ecology. The benefits of aggregation of conspecific individuals are central to Allee effects, which have led to the widely held assumption that social species are more prone to Allee effects. Robust evidence for this assumption, however, remains rare. Furthermore, previous research on Allee effects has failed to adequately address the consequences of the different levels of organisation within social species' populations. Here, we review available evidence of Allee effects and model the role of demographic and behavioural factors that may combine to dampen or strengthen Allee effects in social species. We use examples across various species with contrasting social structure, including carnivores, bats, primates and eusocial insects. Building on this, we provide a conceptual framework that allows for the integration of different Allee effects in social species. Social species are characterised by nested levels of organisation. The benefits of cooperation, measured by mean individual fitness, can be observed at both the population and group levels, giving rise to "population level" and "group level" Allee effects respectively. We also speculate on the possibility of a third level, reporting per capita benefits for different individuals within a group (e.g. castes in social insects). We show that group size heterogeneity and intergroup interactions affect the strength of population-level demographic Allee effects. Populations with higher group size heterogeneity and in which individual social groups cooperate demonstrate the weakest Allee effects and may thus provide an explanation for why extinctions due to Allee effects are rare in social species. More adequately accounting for Allee effects in social species will improve our understanding of the ecological and evolutionary implications of cooperation in social species. © 2017 The Authors. Journal of Animal Ecology © 2017 British

How much variation can one ant species hold? Species delimitation in the Crematogaster kelleri-group in Madagascar.

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Bonnie B Blaimer

Full Text Available We investigated the species-level taxonomy of the Malagasy Crematogaster (Crematogaster kelleri-group and an additional more distantly related species of the same subgenus. Morphological data from worker, queen and male ants, as well as genetic data from three nuclear genes (long wavelength rhodopsin, arginine kinase and carbomoylphosphate synthase and one mitochondrial marker (cytochrome oxidase I led to the recognition of six species. Within the C. kelleri-group, three new species are described: C. hazolava Blaimer sp. n., C. hafahafa Blaimer sp. n. and C. tavaratra Blaimer sp. n. The previously described taxa C. kelleri Forel and C. madagascariensis André are validated by our analysis. Conversely, our data suggests synonymy of C. adrepens Forel (with C. kelleri and C. gibba Emery (with C. madagascariensis. A more distantly related and phylogenetically isolated species, C. tsisitsilo Blaimer sp. n., is further described. We report high levels of morphological and molecular variation in C. kelleri and illustrate that this variation can be explained partly by geography. Species descriptions, images, distribution maps and identification keys based on worker ants, as well as on queen and male ants where available, are presented for all six species. Our work highlights the elevated species richness of Crematogaster ants throughout Madagascar's humid forests, especially in the far northern tip of the island, and the need to use multiple data sources to ensure clear demarcation of this diversity.

Species rarity: definition, causes, and classification

Science.gov (United States)

Curtis H. Flather; Carolyn Hull Sieg

2007-01-01

In virtually all ecological communities around the world, most species are represented by few individuals, and most individuals come from only a few of the most common species. Why this distribution of species abundances is so regularly observed among different taxonomic sets in geographically diverse systems is a question that has received considerable theoretical and...

77 FR 59842 - Atlantic Highly Migratory Species; 2006 Consolidated Highly Migratory Species Fishery Management...

Science.gov (United States)

2012-10-01

... vessels permitted in the Atlantic tunas General category in Puerto Rico and 10 in the U.S. Virgin Islands... [Docket No. 080603729-2454-02] RIN 0648-AW83 Atlantic Highly Migratory Species; 2006 Consolidated Highly... management plan (FMP) amendment addresses Atlantic highly migratory species (HMS) fishery management measures...

Phytochemistry and Pharmacology of Berberis Species

Science.gov (United States)

Mokhber-Dezfuli, Najmeh; Saeidnia, Soodabeh; Gohari, Ahmad Reza; Kurepaz-Mahmoodabadi, Mahdieh

2014-01-01

The genus Berberis (Berberidaceae) includes about 500 species worldwide, some of which are widely cultivated in the north-eastern regions of Iran. This genus consists of spiny deciduous evergreen shrubs, characterized by yellow wood and flowers. The cultivation of seedless barberry in South Khorasan goes back to two hundred years ago. Medicinal properties for all parts of these plants have been reported, including: Antimicrobial, antiemetic, antipyretic, antioxidant, anti-inflammatory, anti-arrhythmic, sedative, anti-cholinergic, cholagogic, anti-leishmaniasis, and anti-malaria. The main compounds found in various species of Berberis, are berberine and berbamine. Phytochemical analysis of various species of this genus revealed the presence of alkaloids, tannins, phenolic compounds, sterols and triterpenes. Although there are some review articles on Berberis vulgaris (as the most applied species), there is no review on the phytochemical and pharmacological activities of other well-known species of the genus Berberis. For this reason, the present review mainly focused on the diverse secondary metabolites of various species of this genus and the considerable pharmacological and biological activities together with a concise story of the botany and cultivation. PMID:24600191

The temporal variability of species densities

International Nuclear Information System (INIS)

Redfearn, A.; Pimm, S.L.

1993-01-01

Ecologists use the term 'stability' to mean to number of different things (Pimm 1984a). One use is to equate stability with low variability in population density over time (henceforth, temporal variability). Temporal variability varies greatly from species to species, so what effects it? There are at least three sets of factors: the variability of extrinsic abiotic factors, food web structure, and the intrinsic features of the species themselves. We can measure temporal variability using at least three statistics: the coefficient of variation of density (CV); the standard deviation of the logarithms of density (SDL); and the variance in the differences between logarithms of density for pairs of consecutive years (called annual variability, hence AV, b y Wolda 1978). There are advantages and disadvantages to each measure (Williamson 1984), though in our experience, the measures are strongly correlated across sets of taxonomically related species. The increasing availability of long-term data sets allows one to calculate these statistics for many species and so to begin to understand the various causes of species differences in temporal variability

Proactive Conservation Program: Species of Concern :: NOAA Fisheries