WorldWideScience

Sample records for biology biomed central

  1. User's Guide to Biome Information from the United States International Biological Program (IBP). First Edition.

    Science.gov (United States)

    Hinckley, A. Dexter; Haug, Peter T.

    This publication is a guide to the biome research conducted under the International Biological Program. The guide lists biome researchers by interest and by biome as well as a central list. A site list, map, information sources section reporting abstracts, bibliographies, journals, books, evaluations, and data books are also included. Three…

  2. Biomes.

    Science.gov (United States)

    Web Feet K-8, 2001

    2001-01-01

    This annotated subject guide to Web sites and additional resources focuses on biomes. Specifies age levels for resources that include Web sites, CD-ROMs and software, videos, books, audios, and magazines; includes professional resources; and presents a relevant class activity. (LRW)

  3. biojs-io-biom, a BioJS component for handling data in Biological Observation Matrix (BIOM format [version 2; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Markus J. Ankenbrand

    2017-01-01

    Full Text Available The Biological Observation Matrix (BIOM format is widely used to store data from high-throughput studies. It aims at increasing interoperability of bioinformatic tools that process this data. However, due to multiple versions and implementation details, working with this format can be tricky. Currently, libraries in Python, R and Perl are available, whilst such for JavaScript are lacking. Here, we present a BioJS component for parsing BIOM data in all format versions. It supports import, modification, and export via a unified interface. This module aims to facilitate the development of web applications that use BIOM data. Finally, we demonstrate its usefulness by two applications that already use this component. Availability: https://github.com/molbiodiv/biojs-io-biom, https://dx.doi.org/10.5281/zenodo.218277

  4. The Biological Observation Matrix (BIOM) format or: how I learned to stop worrying and love the ome-ome.

    Science.gov (United States)

    McDonald, Daniel; Clemente, Jose C; Kuczynski, Justin; Rideout, Jai Ram; Stombaugh, Jesse; Wendel, Doug; Wilke, Andreas; Huse, Susan; Hufnagle, John; Meyer, Folker; Knight, Rob; Caporaso, J Gregory

    2012-07-12

    We present the Biological Observation Matrix (BIOM, pronounced "biome") format: a JSON-based file format for representing arbitrary observation by sample contingency tables with associated sample and observation metadata. As the number of categories of comparative omics data types (collectively, the "ome-ome") grows rapidly, a general format to represent and archive this data will facilitate the interoperability of existing bioinformatics tools and future meta-analyses. The BIOM file format is supported by an independent open-source software project (the biom-format project), which initially contains Python objects that support the use and manipulation of BIOM data in Python programs, and is intended to be an open development effort where developers can submit implementations of these objects in other programming languages. The BIOM file format and the biom-format project are steps toward reducing the "bioinformatics bottleneck" that is currently being experienced in diverse areas of biological sciences, and will help us move toward the next phase of comparative omics where basic science is translated into clinical and environmental applications. The BIOM file format is currently recognized as an Earth Microbiome Project Standard, and as a Candidate Standard by the Genomic Standards Consortium.

  5. The Biological Observation Matrix (BIOM format or: how I learned to stop worrying and love the ome-ome

    Directory of Open Access Journals (Sweden)

    McDonald Daniel

    2012-07-01

    Full Text Available Abstract Background We present the Biological Observation Matrix (BIOM, pronounced “biome” format: a JSON-based file format for representing arbitrary observation by sample contingency tables with associated sample and observation metadata. As the number of categories of comparative omics data types (collectively, the “ome-ome” grows rapidly, a general format to represent and archive this data will facilitate the interoperability of existing bioinformatics tools and future meta-analyses. Findings The BIOM file format is supported by an independent open-source software project (the biom-format project, which initially contains Python objects that support the use and manipulation of BIOM data in Python programs, and is intended to be an open development effort where developers can submit implementations of these objects in other programming languages. Conclusions The BIOM file format and the biom-format project are steps toward reducing the “bioinformatics bottleneck” that is currently being experienced in diverse areas of biological sciences, and will help us move toward the next phase of comparative omics where basic science is translated into clinical and environmental applications. The BIOM file format is currently recognized as an Earth Microbiome Project Standard, and as a Candidate Standard by the Genomic Standards Consortium.

  6. A mesic maximum in biological water use demarcates biome sensitivity to aridity shifts.

    Science.gov (United States)

    Good, Stephen P; Moore, Georgianne W; Miralles, Diego G

    2017-12-01

    Biome function is largely governed by how efficiently available resources can be used and yet for water, the ratio of direct biological resource use (transpiration, E T ) to total supply (annual precipitation, P) at ecosystem scales remains poorly characterized. Here, we synthesize field, remote sensing and ecohydrological modelling estimates to show that the biological water use fraction (E T /P) reaches a maximum under mesic conditions; that is, when evaporative demand (potential evapotranspiration, E P ) slightly exceeds supplied precipitation. We estimate that this mesic maximum in E T /P occurs at an aridity index (defined as E P /P) between 1.3 and 1.9. The observed global average aridity of 1.8 falls within this range, suggesting that the biosphere is, on average, configured to transpire the largest possible fraction of global precipitation for the current climate. A unimodal E T /P distribution indicates that both dry regions subjected to increasing aridity and humid regions subjected to decreasing aridity will suffer declines in the fraction of precipitation that plants transpire for growth and metabolism. Given the uncertainties in the prediction of future biogeography, this framework provides a clear and concise determination of ecosystems' sensitivity to climatic shifts, as well as expected patterns in the amount of precipitation that ecosystems can effectively use.

  7. Evolutionary biology and anthropology suggest biome reconstitution as a necessary approach toward dealing with immune disorders.

    Science.gov (United States)

    Parker, William; Ollerton, Jeff

    2013-01-01

    Industrialized society currently faces a wide range of non-infectious, immune-related pandemics. These pandemics include a variety of autoimmune, inflammatory and allergic diseases that are often associated with common environmental triggers and with genetic predisposition, but that do not occur in developing societies. In this review, we briefly present the idea that these pandemics are due to a limited number of evolutionary mismatches, the most damaging being 'biome depletion'. This particular mismatch involves the loss of species from the ecosystem of the human body, the human biome, many of which have traditionally been classified as parasites, although some may actually be commensal or even mutualistic. This view, evolved from the 'hygiene hypothesis', encompasses a broad ecological and evolutionary perspective that considers host-symbiont relations as plastic, changing through ecological space and evolutionary time. Fortunately, this perspective provides a blueprint, termed 'biome reconstitution', for disease treatment and especially for disease prevention. Biome reconstitution includes the controlled and population-wide reintroduction (i.e. domestication) of selected species that have been all but eradicated from the human biome in industrialized society and holds great promise for the elimination of pandemics of allergic, inflammatory and autoimmune diseases.

  8. Toward Understanding Dynamics in Shifting Biomes: An Individual Based Modeling Approach to Characterizing Drought and Mortality in Central Western Canada

    Science.gov (United States)

    Armstrong, A. H.; Foster, A.; Rogers, B. M.; Hogg, T.; Michaelian, M.; Shuman, J. K.; Shugart, H. H., Jr.; Goetz, S. J.

    2017-12-01

    The Arctic-Boreal zone is known be warming at an accelerated rate relative to other biomes. Persistent warming has already affected the high northern latitudes, altering vegetation productivity, carbon sequestration, and many other ecosystem processes and services. The central-western Canadian boreal forests and aspen parkland are experiencing a decade long drought, and rainfall has been identified as a key factor controlling the location of the boundary between forest and prairie in this region. Shifting biome with related greening and browning trends are readily measureable with remote sensing, but the dynamics that create and result from them are not well understood. In this study, we use the University of Virginia Forest Model Enhanced (UVAFME), an individual-based forest model, to simulate the changes that are occurring across the southern boreal and parkland forests of west-central Canada. We present a parameterization of UVAFME for western central Canadian forests, validated with CIPHA data (Climate Change Impacts on the Productivity and Health of Aspen), and improved mortality. In order to gain a fine-scale understanding of how climate change and specifically drought will continue to affect the forests of this region, we simulated forest conditions following CMIP5 climate scenarios. UVAFME predictions were compared with statistical models and satellite observations of productivity across the landscape. Changes in forest cover, forest type, aboveground biomass, and mortality and recruitment dynamics are presented, highlighting the high vulnerability of this region to vegetation transitions associated with future droughts.

  9. Aquatic ecosystem responses to Holocene climate change and biome development in boreal, central Asia

    Science.gov (United States)

    Mackay, Anson W.; Bezrukova, Elena V.; Leng, Melanie J.; Meaney, Miriam; Nunes, Ana; Piotrowska, Natalia; Self, Angela; Shchetnikov, Alexander; Shilland, Ewan; Tarasov, Pavel; Wang, Luo; White, Dustin

    2012-05-01

    Boreal ecosystems are highly vulnerable to climate change, and severe ecological impacts in the near future are virtually certain to occur. We undertook a multiproxy study on an alpine lake (ESM-1) at the modern tree-line in boreal, southern Siberia. Steppe and tundra biomes were extensive in eastern Sayan landscapes during the early Holocene. Boreal forest quickly expanded by 9.1 ka BP, and dominated the landscape until c 0.7 ka BP, when the greatest period of compositional turnover occurred. At this time, alpine meadow landscape expanded and Picea obovata colonised new habitats along river valleys and lake shorelines, because of prevailing cool, moist conditions. During the early Holocene, chironomid assemblages were dominated by cold stenotherms. Diatoms for much of the Holocene were dominated by alkaliphilous, fragilarioid taxa, up until 0.2 ka BP, when epiphytic species expanded, indicative of increased habitat availability. C/N mass ratios ranged between 9.5 and 13.5 (11.1-15.8 C/N atomic ratios), indicative of algal communities dominating organic matter contributions to bottom sediments with small, persistent contributions from vascular plants. However, δ13C values increased steadily from -34.9‰ during the early Holocene (9.3 ka BP) to -24.8‰ by 0.6 ka BP. This large shift in magnitude may be due to a number of factors, including increasing within-lake productivity, increasing disequilibrium between the isotopic balance of the lake with the atmosphere as the lake became isotopically ‘mature’, and declining soil respiration linked to small, but distinct retreat in forest biomes. The influence of climatic variables on landscape vegetation was assessed using redundancy analysis (RDA), a linear, direct ordination technique. Changes in July insolation at 60 °N significantly explained over one-fifth of the variation in species composition, while changes in estimates of northern hemisphere temperature and ice-rafted debris events in the North Atlantic

  10. The Central Dogma of Molecular Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 3. The Central Dogma of Molecular Biology - A Retrospective after Fifty Years. Michel Morange. General Article Volume 14 Issue 3 March 2009 pp 236-247. Fulltext. Click here to view fulltext PDF. Permanent link:

  11. Biology of the Central Desert of Oman

    OpenAIRE

    GHAZANFAR, Shahina A

    2004-01-01

    A biological survey of the central desert of Oman was done using long distance transects. Vegetation was sparse and consisted of 200+ plant species, 22 species of mammals, 17 species of reptiles and amphibians, and more than 50 species of birds (migratory and resident). Three main vegetation types were identified based on ground substrate and the dominance of species. These were communities with Acacia Willd., Zygophyllum L., and open woodlands of Prosopis cineraria (L.) Druce. Over-grazing a...

  12. The central dogma of cell biology.

    Science.gov (United States)

    Cooper, S

    1981-06-01

    The Continuum Model proposes that preparations for DNA synthesis occur continuously during all phases of the division cycle. Various stimuli activate cell proliferation by changing the rate of initiator (protein) synthesis. Cell division does not initiate any process regulating cell proliferation. Cell division is the end of a process and the beginning of nothing. The alternative model which has cell proliferation regulated in the G1 phase of the division cycle is reexamined and the two types of evidence for this model, G1-variability and G1-arrest are shown to be compatible with the Continuum Model. Here, the Continuum Model is generalized to produce a new look at the logic of the division cycle in prokaryotes and eukaryotes. This new view, the Central Dogma of Cell Biology, is presented and two predictions are made. I propose that (i) cell division does not have any regulatory function, and (ii) that DNA synthesis may, indeed, have some affect on the synthesis of initiator.

  13. Flavonoid Composition and Biological Activities of Ethanol Extracts of Caryocar coriaceum Wittm., a Native Plant from Caatinga Biome

    Directory of Open Access Journals (Sweden)

    Daniela Ribeiro Alves

    2017-01-01

    Full Text Available Caryocar coriaceum fruits, found in Brazilian Cerrado and Caatinga, are commonly used as food and in folk medicine, as anti-inflammatory, bactericide, fungicide, leishmanicide, and nematicide. Due to the biological potential of this plant, this study focuses on the evaluation of antifungal and antileishmanial activities, including anticholinesterase and antioxidant tests, correlating with total phenols and flavonoids content. Peel extracts contain higher yield of phenols and flavonoids as analyzed by spectrophotometric methods. HPLC analysis of flavonoids revealed that isoquercitrin is the main flavonoid in both parts of the fruit, and peel extract showed the best antioxidant activity. In the inhibition of the acetylcholinesterase assay, both extracts demonstrate action comparable to physostigmine. The antimicrobial activity of extracts was evaluated against strains of Malassezia sp. and Microsporum canis, using the broth microdilution technique, in which the extracts showed similar MIC and MFC. The extracts present antileishmanial activity and low toxicity on murine macrophages and erythrocytes. Therefore, these results suggest a potential for the application of C. coriaceum fruit’s ethanol extracts in the treatment against dermatophyte fungi and leishmaniasis, probably due to the presence of active flavonoids. Further in vivo studies are recommended aiming at the development of possible new pharmaceutical compounds.

  14. Biosphere 2's Marsh Biome

    Science.gov (United States)

    Molnar, Jennifer; Goodridge, Kelven

    1997-01-01

    The Marsh Biome, which was modeled after the mangroves and marshes of southwest Florida, has an area of 441.2 sq m separated into three hydrologically independent sections: the Freshwater, Oligohaline and Salt Marshes. The divisions are made based on their salinity (approximately 0, 4, and 34 ppt. respectively), but they also contain different biological communities. The Freshwater and Oligohaline Marshes are mostly filled with various grasses and several trees, while the Salt Marsh houses regions of red, black, and white mangroves (Rhizophora mangle, Avicennia germinans, and Languncularia racemosa respectively). Overall, there are an estimated 80 species of plants within the biome. Water in the Salt Marsh follows a meandering stream from the algal turf scrubbers (apparatuses that clean the water of its nutrients and heavy metals while increasing dissolved oxygen levels) which have an outlet in the Salt Marsh section near sites 4 and 5 to the Fringing Red Mangrove section. The sections of the Salt Marsh are separated by walls of concrete with openings to allow the stream to flow through. Throughout this study, conducted through the months of June and July, many conditions within the biome remained fairly constant. The temperature was within a degree or two of 25 C, mostly depending on whether the sample site was in direct sunlight or shaded. The pH throughout the Salt Marsh was 8.0 +/- 0.2, and the lower salinity waters only dropped below this soon after rains. The water rdepth and dissolved oxygen varied, however, between sites.

  15. Consequences of biome depletion

    International Nuclear Information System (INIS)

    Salvucci, Emiliano

    2013-01-01

    The human microbiome is an integral part of the superorganism together with their host and they have co-evolved since the early days of the existence of the human species. The modification of the microbiome as a result changes in food and social habits of human beings throughout their life history has led to the emergence of many diseases. In contrast with the Darwinian view of nature of selfishness and competence, new holistic approaches are rising. Under these views, the reconstitution of the microbiome comes out as a fundamental therapy for emerging diseases related to biome depletion.

  16. Biogeography of photoautotrophs in the high polar biome

    Directory of Open Access Journals (Sweden)

    Stephen Brian Pointing

    2015-09-01

    Full Text Available The global latitudinal gradient in biodiversity weakens in the high polar biome and so an alternative explanation for distribution of Arctic and Antarctic photoautotrophs is required. Here we identify how temporal, microclimate and evolutionary drivers of biogeography are important, rather than the macroclimate features that drive plant diversity patterns elsewhere. High polar ecosystems are biologically unique, with a more central role for bryophytes, lichens and microbial photoautotrophs over that of vascular plants. Constraints on vascular plants arise mainly due to stature and ontogenetic barriers. Conversely non-vascular plant and microbial photoautotroph distribution is correlated with favourable microclimates and the capacity for poikilohydric dormancy. Contemporary distribution also depends on evolutionary history, with adaptive and dispersal traits as well as legacy influencing biogeography. We highlight the relevance of these findings to predicting future impacts on polar plant diversity and to the current status of plants in Arctic and Antarctic conservation policy frameworks.

  17. Disturbance maintains alternative biome states.

    Science.gov (United States)

    Dantas, Vinícius de L; Hirota, Marina; Oliveira, Rafael S; Pausas, Juli G

    2016-01-01

    Understanding the mechanisms controlling the distribution of biomes remains a challenge. Although tropical biome distribution has traditionally been explained by climate and soil, contrasting vegetation types often occur as mosaics with sharp boundaries under very similar environmental conditions. While evidence suggests that these biomes are alternative states, empirical broad-scale support to this hypothesis is still lacking. Using community-level field data and a novel resource-niche overlap approach, we show that, for a wide range of environmental conditions, fire feedbacks maintain savannas and forests as alternative biome states in both the Neotropics and the Afrotropics. In addition, wooded grasslands and savannas occurred as alternative grassy states in the Afrotropics, depending on the relative importance of fire and herbivory feedbacks. These results are consistent with landscape scale evidence and suggest that disturbance is a general factor driving and maintaining alternative biome states and vegetation mosaics in the tropics. © 2015 John Wiley & Sons Ltd/CNRS.

  18. Evolution of the indoor biome.

    Science.gov (United States)

    Martin, Laura J; Adams, Rachel I; Bateman, Ashley; Bik, Holly M; Hawks, John; Hird, Sarah M; Hughes, David; Kembel, Steven W; Kinney, Kerry; Kolokotronis, Sergios-Orestis; Levy, Gabriel; McClain, Craig; Meadow, James F; Medina, Raul F; Mhuireach, Gwynne; Moreau, Corrie S; Munshi-South, Jason; Nichols, Lauren M; Palmer, Clare; Popova, Laura; Schal, Coby; Täubel, Martin; Trautwein, Michelle; Ugalde, Juan A; Dunn, Robert R

    2015-04-01

    Few biologists have studied the evolutionary processes at work in indoor environments. Yet indoor environments comprise approximately 0.5% of ice-free land area--an area as large as the subtropical coniferous forest biome. Here we review the emerging subfield of 'indoor biome' studies. After defining the indoor biome and tracing its deep history, we discuss some of its evolutionary dimensions. We restrict our examples to the species found in human houses--a subset of the environments constituting the indoor biome--and offer preliminary hypotheses to advance the study of indoor evolution. Studies of the indoor biome are situated at the intersection of evolutionary ecology, anthropology, architecture, and human ecology and are well suited for citizen science projects, public outreach, and large-scale international collaborations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Biomes computed from simulated climatologies

    Energy Technology Data Exchange (ETDEWEB)

    Claussen, M.; Esch, M. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany)

    1994-01-01

    The biome model of Prentice et al. is used to predict global patterns of potential natural plant formations, or biomes, from climatologies simulated by ECHAM, a model used for climate simulations at the Max-Planck-Institut fuer Meteorologie. This study undertaken in order to show the advantage of this biome model in diagnosing the performance of a climate model and assessing effects of past and future climate changes predicted by a climate model. Good overall agreement is found between global patterns of biomes computed from observed and simulated data of present climate. But there are also major discrepancies indicated by a difference in biomes in Australia, in the Kalahari Desert, and in the Middle West of North America. These discrepancies can be traced back to in simulated rainfall as well as summer or winter temperatures. Global patterns of biomes computed from an ice age simulation reveal that North America, Europe, and Siberia should have been covered largely by tundra and taiga, whereas only small differences are for the tropical rain forests. A potential northeast shift of biomes is expected from a simulation with enhanced CO{sub 2} concentration according to the IPCC Scenario A. Little change is seen in the tropical rain forest and the Sahara. Since the biome model used is not capable of predicting chances in vegetation patterns due to a rapid climate change, the latter simulation to be taken as a prediction of chances in conditions favourable for the existence of certain biomes, not as a reduction of a future distribution of biomes. 15 refs., 8 figs., 2 tabs.

  20. Biomes computed from simulated climatologies

    Energy Technology Data Exchange (ETDEWEB)

    Claussen, W.; Esch, M.

    1992-09-01

    The biome model of Prentice et al. is used to predict global patterns of potential natural plant formations, or biomes, from climatologies simulated by ECHAM, a model used for climate simulations at the Max-Planck-Institut fuer Meteorologie. This study is undertaken in order to show the advantage of this biome model in comprehensively diagnosing the performance of a climate model and assessing effects of past and future climate changes predicted by a climate model. Good overall agreement is found between global patterns of biomes computed from observed and simulated data of present climate. But there are also major discrepancies indicated by a difference in biomes in Australia, in the Kalahari Desert, and in the Middle West of North America. These discrepancies can be traced back to failures in simulated rain fall as well as summer or winter temperatures. Global patterns of biomes computed from an ice age simulation reveal that North America, Europe, and Siberia should have been covered largely by tundra and taiga, whereas only small differences are seen for the tropical rain forests. A potential North-East shift of biomes is expected from a simulation with enhanced CO{sub 2} concentration according to the IPCC Scenario A. Little change is seen in the tropical rain forest and the Sahara. Since the biome model used is not capable of predicting changes in vegetation patterns due to a rapid climate change, the latter simulation has to be taken as a prediction of changes in conditions favorable for the existence of certain biomes, not as a prediction of a future distribution of biomes. (orig.).

  1. The Brazilian Pampa: A Fragile Biome

    Directory of Open Access Journals (Sweden)

    Valdir Marcos Stefenon

    2009-12-01

    Full Text Available Biodiversity is one of the most fundamental properties of Nature. It underpins the stability of ecosystems, provides vast bioresources for economic use, and has important cultural significance for many people. The Pampa biome, located in the southernmost state of Brazil, Rio Grande do Sul, illustrates the direct and indirect interdependence of humans and biodiversity. The Brazilian Pampa lies within the South Temperate Zone where grasslands scattered with shrubs and trees are the dominant vegetation. The soil, originating from sedimentary rocks, often has an extremely sandy texture that makes them fragile—highly prone to water and wind erosion. Human activities have converted or degraded many areas of this biome. In this review we discuss our state-of-the-art knowledge of the diversity and the major biological features of this regions and the cultural factors that have shaped it. Our aim is to contribute toward a better understanding of the current status of this special biome and to describe how the interaction between human activities and environment affects the region, highlighting the fragility of the Brazilian Pampa.

  2. Exploration of the central dogma at the interface of chemistry and biology: 2010 Yale Chemical Biology Symposium.

    Science.gov (United States)

    Zhou, Alice Qinhua

    2010-09-01

    Ever since the term "central dogma" was coined in 1958, researchers have sought to control information flow from nucleic acids to proteins. Talks delivered by Drs. Anna Pyle and Hiroaki Suga at this year's Chemical Biology Symposium at Yale in May 2010 applauded recent advances in this area, at the interface between chemistry and biology.

  3. Factors affecting ammonium uptake in streams - an inter-biome perspective

    Science.gov (United States)

    Jackson R Webster; Partick J. Mulholland; Jennifer L. Tanks; H. Maurice Valett; Walter K. Dodds; Bruce J. Peterson; William B. Bowden; Clifford N. Dahm; Stuart Findlay; Stanley V. Gregory; Nancy B. Grimm; Stephen K. Hamilton; Sherri L. Johnson; Eugenia Marti; William H. McDowell; Judy L. Meyer; Donna D. Morrall; Steven A. Thomas; Wilfred M. Wollhem

    2003-01-01

    1. The Lotic Intersite Nitrogen experiment (LINX) was a coordinated study of the relationships between North American biomes and factors governing ammonium uptake in streams. Our objective was to relate inter-biome variability of ammonium uptake to physical, chemical and biological processes. 2. Data were collected from 11 streams ranging from arctic to tropical and...

  4. Description of the Karoo Biome project

    CSIR Research Space (South Africa)

    Cowling, RM

    1986-01-01

    Full Text Available The ecological characteristics and ecological problems of the karoo biome are briefly described. A conceptual basis and guidelines for the development of the Karoo Biome Project are outlined by addressing project goals, project structure...

  5. Description of the Grassland Biome Project

    CSIR Research Space (South Africa)

    Mentis, MT

    1982-10-01

    Full Text Available The objectives, organization and research programme of the Grassland Biome Project are described against a background of the biome's ecological characteristics and environmental problems. Four principal research topics wil 1 be focused upon: (i...

  6. Biological flora of the Central Europe: Rumex alpinus

    Czech Academy of Sciences Publication Activity Database

    Šťastná, P.; Klimeš, Leoš; Klimešová, Jitka

    2010-01-01

    Roč. 12, č. 1 (2010), s. 67-79 ISSN 1433-8319 R&D Projects: GA ČR GA526/07/0808 Institutional research plan: CEZ:AV0Z60050516 Keywords : biology * Rumex alpinus * distribution area Subject RIV: EF - Botanics Impact factor: 4.488, year: 2010

  7. Biology of larks (Aves: Alaudidae) in the central Namib Desert ...

    African Journals Online (AJOL)

    The biology of six species of larks in the Namib Desert near Walvis Bay, South West Africa, was studied in 1964, 1965 and 1966. 2. All species reproduced following rainfall in summer and autumn months, with the appearance of green grass and abundant insects on which the birds fed. 3. The primarily insectivorous species ...

  8. Physical, Nutrient, and Biological Measurements of Coastal Waters off Central California in November 2007

    National Research Council Canada - National Science Library

    Rago, Thomas A; Michisaki, Reiko; Marinovic, Baldo; Blum, Marguerite; Whitaker, Katherine

    2008-01-01

    The results of analyses of hydrographic, nutrient, and biological data collected in coastal ocean waters off Central California in November 2007 aboard the NOAA Ship David Starr Jordan are presented...

  9. Why the Central Dogma: on the nature of the great biological exclusion principle.

    Science.gov (United States)

    Koonin, Eugene V

    2015-09-16

    The Central Dogma of molecular biology posits that transfer of information from proteins back to nucleic acids does not occur in biological systems. I argue that the impossibility of reverse translation is indeed a major, physical exclusion principle that emerges due to the transition from the digital information carriers, nucleic acids, to analog information carriers, proteins, which involves irreversible suppression of the digital information.

  10. Exploration of the Central Dogma at the Interface of Chemistry and Biology

    Science.gov (United States)

    Zhou, Alice Qinhua

    2010-01-01

    Ever since the term “central dogma” was coined in 1958, researchers have sought to control information flow from nucleic acids to proteins. Talks delivered by Drs. Anna Pyle and Hiroaki Suga at this year’s Chemical Biology Symposium at Yale in May 2010 applauded recent advances in this area, at the interface between chemistry and biology. PMID:20885900

  11. Exploration of the Central Dogma at the Interface of Chemistry and Biology

    OpenAIRE

    Zhou, Alice Qinhua

    2010-01-01

    Ever since the term ?central dogma? was coined in 1958, researchers have sought to control information flow from nucleic acids to proteins. Talks delivered by Drs. Anna Pyle and Hiroaki Suga at this year?s Chemical Biology Symposium at Yale in May 2010 applauded recent advances in this area, at the interface between chemistry and biology.

  12. Rethinking the central dogma: noncoding RNAs are biologically relevant.

    Science.gov (United States)

    Robinson, Victoria L

    2009-01-01

    Non-coding RNAs (ncRNAs) are a large class of functional molecules with over 100 unique classes described to date. ncRNAs are diverse in terms of their function and size. A relatively new class of small ncRNA, called microRNAs (miRNA), have received a great deal of attention in the literature in recent years. miRNAs are endogenously encoded gene families that demonstrate striking evolutionary conservation. miRNAs serve essential and diverse physiological functions such as differentiation and development, proliferation, maintaining cell type phenotypes, and many others. The discovery and ongoing investigation of miRNAs is part of a revolution in biology that is changing the basic concepts of gene expression and RNA functionality. A single miRNA can participate in controlling the expression of up to several hundred protein-coding genes by interacting with mRNAs, generally in 3' untranslated regions. Our new and developing understanding of miRNAs, and other ncRNAs, promises to lead to significant contributions to medicine. Specifically, miRNAs are likely to serve as the basis for novel therapies and diagnostic tools.

  13. Using Analogy Role-Play Activity in an Undergraduate Biology Classroom to Show Central Dogma Revision

    Science.gov (United States)

    Takemura, Masaharu; Kurabayashi, Mario

    2014-01-01

    For the study of biology in an undergraduate classroom, a classroom exercise was developed: an analogy role-play to learn mechanisms of gene transcription and protein translation (central dogma). To develop the central dogma role-play exercise, we made DNA and mRNA using paper sheets, tRNA using a wire dress hanger, and amino acids using Lego®…

  14. BioMart Central Portal: an open database network for the biological community

    OpenAIRE

    Guberman, Jonathan M.; Ai, J.; Arnaiz, O.; Baran, Joachim; Blake, Andrew; Baldock, Richard; Chelala, Claude; Croft, David; Cros, Anthony; Cutts, Rosalind J.; Di Genova, A.; Forbes, Simon; Fujisawa, T.; Gadaleta, E.; Goodstein, D. M.

    2011-01-01

    International audience; BioMart Central Portal is a first of its kind, community-driven effort to provide unified access to dozens of biological databases spanning genomics, proteomics, model organisms, cancer data, ontology information and more. Anybody can contribute an independently maintained resource to the Central Portal, allowing it to be exposed to and shared with the research community, and linking it with the other resources in the portal. Users can take advantage of the common inte...

  15. Why the Central Dogma: on the nature of the great biological exclusion principle

    OpenAIRE

    Koonin, Eugene V.

    2015-01-01

    Abstract The Central Dogma of molecular biology posits that transfer of information from proteins back to nucleic acids does not occur in biological systems. I argue that the impossibility of reverse translation is indeed a major, physical exclusion principle that emerges due to the transition from the digital information carriers, nucleic acids, to analog information carriers, proteins, which involves irreversible suppression of the digital information. Reviewers This article was reviewed by...

  16. An attempt to understand glioma stem cell biology through centrality analysis of a protein interaction network.

    Science.gov (United States)

    Mallik, Mrinmay Kumar

    2018-02-07

    Biological networks can be analyzed using "Centrality Analysis" to identify the more influential nodes and interactions in the network. This study was undertaken to create and visualize a biological network comprising of protein-protein interactions (PPIs) amongst proteins which are preferentially over-expressed in glioma cancer stem cell component (GCSC) of glioblastomas as compared to the glioma non-stem cancer cell (GNSC) component and then to analyze this network through centrality analyses (CA) in order to identify the essential proteins in this network and their interactions. In addition, this study proposes a new centrality analysis method pertaining exclusively to transcription factors (TFs) and interactions amongst them. Moreover the relevant molecular functions, biological processes and biochemical pathways amongst these proteins were sought through enrichment analysis. A protein interaction network was created using a list of proteins which have been shown to be preferentially expressed or over-expressed in GCSCs isolated from glioblastomas as compared to the GNSCs. This list comprising of 38 proteins, created using manual literature mining, was submitted to the Reactome FIViz tool, a web based application integrated into Cytoscape, an open source software platform for visualizing and analyzing molecular interaction networks and biological pathways to produce the network. This network was subjected to centrality analyses utilizing ranked lists of six centrality measures using the FIViz application and (for the first time) a dedicated centrality analysis plug-in ; CytoNCA. The interactions exclusively amongst the transcription factors were nalyzed through a newly proposed centrality analysis method called "Gene Expression Associated Degree Centrality Analysis (GEADCA)". Enrichment analysis was performed using the "network function analysis" tool on Reactome. The CA was able to identify a small set of proteins with consistently high centrality ranks that

  17. High biological productivity in the central Arabian Sea during the summer monsoon driven by Ekman pumping and lateral advection

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Madhupratap, M.; DileepKumar, M.; Muraleedharan, P.M.; DeSouza, S.N.; Gauns, M.; Sarma, V.V.S.S.

    Open oceans are generally oligotrophic and support less biological production. Results from the central Arabian Sea show that it may be an exception to this. We provide the observational evidence of fairly high biological production (up to 1700 mg C...

  18. Phylogenetic biome conservatism on a global scale.

    Science.gov (United States)

    Crisp, Michael D; Arroyo, Mary T K; Cook, Lyn G; Gandolfo, Maria A; Jordan, Gregory J; McGlone, Matt S; Weston, Peter H; Westoby, Mark; Wilf, Peter; Linder, H Peter

    2009-04-09

    How and why organisms are distributed as they are has long intrigued evolutionary biologists. The tendency for species to retain their ancestral ecology has been demonstrated in distributions on local and regional scales, but the extent of ecological conservatism over tens of millions of years and across continents has not been assessed. Here we show that biome stasis at speciation has outweighed biome shifts by a ratio of more than 25:1, by inferring ancestral biomes for an ecologically diverse sample of more than 11,000 plant species from around the Southern Hemisphere. Stasis was also prevalent in transocean colonizations. Availability of a suitable biome could have substantially influenced which lineages establish on more than one landmass, in addition to the influence of the rarity of the dispersal events themselves. Conversely, the taxonomic composition of biomes has probably been strongly influenced by the rarity of species' transitions between biomes. This study has implications for the future because if clades have inherently limited capacity to shift biomes, then their evolutionary potential could be strongly compromised by biome contraction as climate changes.

  19. Terrestrial ecology. Comprehensive study of the grassland biome

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Terrestrial ecology and grassland biome studies are designed to characterize the biota of the Hanford Reservation, elucidate seasonal dynamics of plant productivity, decomposition and mineral behavior patterns of important plant communities, and, to study the response of these communities to important natural environmental stresses, such as weather, wildfire and man-induced alterations of communities (influenced by grazing cattle and severe mechanical disturbance of the soil, such as affected by plowing or burial of waste materials or construction activities). A detailed account of the important findings of a 5-yr study is currently being prepared by the terrestrial ecology section staff for publication as a contribution to the International Biological Program Grassland Biome project

  20. Tracking the Resolution of Student Misconceptions about the Central Dogma of Molecular Biology.

    Science.gov (United States)

    Briggs, Amy G; Morgan, Stephanie K; Sanderson, Seth K; Schulting, Molly C; Wieseman, Laramie J

    2016-12-01

    The goal of our study was to track changes in student understanding of the central dogma of molecular biology before and after taking a genetics course. Concept maps require the ability to synthesize new information into existing knowledge frameworks, and so the hypothesis guiding this study was that student performance on concept maps reveals specific central dogma misconceptions gained, lost, and retained by students. Students in a genetics course completed pre- and posttest concept mapping tasks using terms related to the central dogma. Student maps increased in complexity and validity, indicating learning gains in both content and complexity of understanding. Changes in each of the 351 possible connections in the mapping task were tracked for each student. Our students did not retain much about the central dogma from their introductory biology courses, but they did move to more advanced levels of understanding by the end of the genetics course. The information they retained from their introductory courses focused on structural components (e.g., protein is made of amino acids) and not on overall mechanistic components (e.g., DNA comes before RNA, the ribosome makes protein). Students made the greatest gains in connections related to transcription, and they resolved the most prior misconceptions about translation. These concept-mapping tasks revealed that students are able to correct prior misconceptions about the central dogma during an intermediate-level genetics course. From these results, educators can design new classroom interventions to target those aspects of this foundational principle with which students have the most trouble.

  1. BioMart Central Portal: an open database network for the biological community

    Science.gov (United States)

    Guberman, Jonathan M.; Ai, J.; Arnaiz, O.; Baran, Joachim; Blake, Andrew; Baldock, Richard; Chelala, Claude; Croft, David; Cros, Anthony; Cutts, Rosalind J.; Di Génova, A.; Forbes, Simon; Fujisawa, T.; Gadaleta, E.; Goodstein, D. M.; Gundem, Gunes; Haggarty, Bernard; Haider, Syed; Hall, Matthew; Harris, Todd; Haw, Robin; Hu, S.; Hubbard, Simon; Hsu, Jack; Iyer, Vivek; Jones, Philip; Katayama, Toshiaki; Kinsella, R.; Kong, Lei; Lawson, Daniel; Liang, Yong; Lopez-Bigas, Nuria; Luo, J.; Lush, Michael; Mason, Jeremy; Moreews, Francois; Ndegwa, Nelson; Oakley, Darren; Perez-Llamas, Christian; Primig, Michael; Rivkin, Elena; Rosanoff, S.; Shepherd, Rebecca; Simon, Reinhard; Skarnes, B.; Smedley, Damian; Sperling, Linda; Spooner, William; Stevenson, Peter; Stone, Kevin; Teague, J.; Wang, Jun; Wang, Jianxin; Whitty, Brett; Wong, D. T.; Wong-Erasmus, Marie; Yao, L.; Youens-Clark, Ken; Yung, Christina; Zhang, Junjun; Kasprzyk, Arek

    2011-01-01

    BioMart Central Portal is a first of its kind, community-driven effort to provide unified access to dozens of biological databases spanning genomics, proteomics, model organisms, cancer data, ontology information and more. Anybody can contribute an independently maintained resource to the Central Portal, allowing it to be exposed to and shared with the research community, and linking it with the other resources in the portal. Users can take advantage of the common interface to quickly utilize different sources without learning a new system for each. The system also simplifies cross-database searches that might otherwise require several complicated steps. Several integrated tools streamline common tasks, such as converting between ID formats and retrieving sequences. The combination of a wide variety of databases, an easy-to-use interface, robust programmatic access and the array of tools make Central Portal a one-stop shop for biological data querying. Here, we describe the structure of Central Portal and show example queries to demonstrate its capabilities. Database URL: http://central.biomart.org. PMID:21930507

  2. Biological therapy in inflammatory bowel diseases: Access in Central and Eastern Europe

    Science.gov (United States)

    Rencz, Fanni; Péntek, Márta; Bortlik, Martin; Zagorowicz, Edyta; Hlavaty, Tibor; Śliwczyński, Andrzej; Diculescu, Mihai M; Kupcinskas, Limas; Gecse, Krisztina B; Gulácsi, László; Lakatos, Peter L

    2015-01-01

    Biological drugs opened up new horizons in the management of inflammatory bowel diseases (IBD). This study focuses on access to biological therapy in IBD patients across 9 selected Central and Eastern European (CEE) countries, namely Bulgaria, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania and Slovakia. Literature data on the epidemiology and disease burden of IBD in CEE countries was systematically reviewed. Moreover, we provide an estimation on prevalence of IBD as well as biological treatment rates. In all countries with the exception of Romania, lower biological treatment rates were observed in ulcerative colitis (UC) compared to Crohn’s disease despite the higher prevalence of UC. Great heterogeneity (up to 96-fold) was found in access to biologicals across the CEE countries. Poland, Bulgaria, Romania and the Baltic States are lagging behind Hungary, Slovakia and the Czech Republic in their access to biologicals. Variations of reimbursement policy may be one of the factors explaining the differences to a certain extent in Bulgaria, Latvia, Lithuania, and Poland, but association with other possible determinants (differences in prevalence and incidence, price of biologicals, total expenditure on health, geographical access, and cost-effectiveness results) was not proven. We assume, nevertheless, that health deterioration linked to IBD might be valued differently against other systemic inflammatory conditions in distinct countries and which may contribute to the immense diversity in the utilization of biological drugs for IBD. In conclusion, access to biologicals varies widely among CEE countries and this difference cannot be explained by epidemiological factors, drug prices or total health expenditure. Changes in reimbursement policy could contribute to better access to biologicals in some countries. PMID:25684937

  3. Of arrows and flows. Causality, determination, and specificity in the Central Dogma of molecular biology.

    Science.gov (United States)

    Fantini, Bernardino

    2006-01-01

    From its first proposal, the Central Dogma had a graphical form, complete with arrows of different types, and this form quickly became its standard presentation. In different scientific contexts, arrows have different meanings and in this particular case the arrows indicated the flow of information among different macromolecules. A deeper analysis illustrates that the arrows also imply a causal statement, directly connected to the causal role of genetic information. The author suggests a distinction between two different kinds of causal links, defined as 'physical causality' and 'biological determination', both implied in the production of biological specificity.

  4. Systems theoretic analysis of the central dogma of molecular biology: some recent results.

    Science.gov (United States)

    Gao, Rui; Yu, Juanyi; Zhang, Mingjun; Tarn, Tzyh-Jong; Li, Jr-Shin

    2010-03-01

    This paper extends our early study on a mathematical formulation of the central dogma of molecular biology, and focuses discussions on recent insights obtained by employing advanced systems theoretic analysis. The goal of this paper is to mathematically represent and interpret the genetic information flow at the molecular level, and explore the fundamental principle of molecular biology at the system level. Specifically, group theory was employed to interpret concepts and properties of gene mutation, and predict backbone torsion angle along the peptide chain. Finite state machine theory was extensively applied to interpret key concepts and analyze the processes related to DNA hybridization. Using the proposed model, we have transferred the character-based model in molecular biology to a sophisticated mathematical model for calculation and interpretation.

  5. Corono-radicular biological restoration of maxillary central incisors by direct method.

    Science.gov (United States)

    Aggarwal, Sonia; Sahoo, Sujit Ranjan; Pandharkar, Kartik

    2014-11-01

    This case report refers to the esthetic and functional restorations of extensively damaged maxillary central incisors with dental caries in a 32-year-old woman, with the use of posts and crowns made from natural extracted teeth. Proper restoration of such teeth with the use of natural teeth fragments are known as "biological restoration." Biological restorations can be done by using the fragments of the patients own tooth and if that is not available, tooth fragment can be obtained from an extracted tooth. These biological posts and crowns present a low cost option and an alternative technique for the morphofunctional recovery of extensively damaged teeth. There are limitations with the use of natural extracted teeth (homogenous bonding) for restoration such as the difficulty of finding teeth with a similar color and shape as that of the destroyed element, or patient may refuse to accept a tooth fragment from another patient, which prevents execution of the restoration.

  6. Shift of biome patterns due to simulated climate variability and climate change

    International Nuclear Information System (INIS)

    Claussen, M.

    1993-01-01

    The variability of simulated equilibrium-response patterns of biomes caused by simulated climate variability and climate shift is analysed. This investigation is based on various realisations of simulated present-day climate and climate shift. It has been found that the difference between biomes computed from three 10-year climatologies and from the corresponding 30-year climatology, simulated by the Hamburg climate model at T21 resolution, amounts to approximately 6% of the total land area, Antarctica excluded. This difference is mainly due to differences in annual moisture availability and winter temperatures. When intercomparing biomes from the 10-year climatologies a 10% difference is seen, but there is no unique difference pattern. In contrast to the interdecadal variability, the shift of conditions favorable for biomes due to a shift in climate in the next 100 years, caused by an increase in sea-surface temperatures and atmospheric CO 2 , reveals a unique trend pattern. It turns out that the strongest and most significant signal is the north-east shift of conditions for boreal biomes. This signal is caused by an increase of annual temperature sums as well as mean temperatures of the coldest and warmest months. Trends in annual moisture availability are of secondary importance globally. Regionally, a decrease in water availability affects biomes in Central and East Europe and an increase of water availability leads to a potential increase in tropical rain forest. In total, all differences amount to roughly 30% of the total land surface, Antarctica excluded. (orig./KW)

  7. Description of the Fynbos Biome Project

    CSIR Research Space (South Africa)

    Kruger, FJ

    1978-06-01

    Full Text Available The objectives, organization and research programme of the Fynbos Biome Project being undertaken in the south-west and southern Cape are described. The project is a cooperative multi-disciplinary study of the ecological characteristics, structure...

  8. Thresholds for boreal biome transitions.

    Science.gov (United States)

    Scheffer, Marten; Hirota, Marina; Holmgren, Milena; Van Nes, Egbert H; Chapin, F Stuart

    2012-12-26

    Although the boreal region is warming twice as fast as the global average, the way in which the vast boreal forests and tundras may respond is poorly understood. Using satellite data, we reveal marked alternative modes in the frequency distributions of boreal tree cover. At the northern end and at the dry continental southern extremes, treeless tundra and steppe, respectively, are the only possible states. However, over a broad intermediate temperature range, these treeless states coexist with boreal forest (∼75% tree cover) and with two more open woodland states (∼20% and ∼45% tree cover). Intermediate tree covers (e.g., ∼10%, ∼30%, and ∼60% tree cover) between these distinct states are relatively rare, suggesting that they may represent unstable states where the system dwells only transiently. Mechanisms for such instabilities remain to be unraveled, but our results have important implications for the anticipated response of these ecosystems to climatic change. The data reveal that boreal forest shows no gradual decline in tree cover toward its limits. Instead, our analysis suggests that it becomes less resilient in the sense that it may more easily shift into a sparse woodland or treeless state. Similarly, the relative scarcity of the intermediate ∼10% tree cover suggests that tundra may shift relatively abruptly to a more abundant tree cover. If our inferences are correct, climate change may invoke massive nonlinear shifts in boreal biomes.

  9. The extent of forest in dryland biomes

    Science.gov (United States)

    Jean-Francois Bastin; Nora Berrahmouni; Alan Grainger; Danae Maniatis; Danilo Mollicone; Rebecca Moore; Chiara Patriarca; Nicolas Picard; Ben Sparrow; Elena Maria Abraham; Kamel Aloui; Ayhan Atesoglu; Fabio Attore; Caglar Bassullu; Adia Bey; Monica Garzuglia; Luis G. GarcÌa-Montero; Nikee Groot; Greg Guerin; Lars Laestadius; Andrew J. Lowe; Bako Mamane; Giulio Marchi; Paul Patterson; Marcelo Rezende; Stefano Ricci; Ignacio Salcedo; Alfonso Sanchez-Paus Diaz; Fred Stolle; Venera Surappaeva; Rene Castro

    2017-01-01

    Dryland biomes cover two-fifths of Earth’s land surface, but their forest area is poorly known. Here, we report an estimate of global forest extent in dryland biomes, based on analyzing more than 210,000 0.5-hectare sample plots through a photo-interpretation approach using large databases of satellite imagery at (i) very high spatial resolution and (ii) very high...

  10. Tracking the Resolution of Student Misconceptions about the Central Dogma of Molecular Biology

    Directory of Open Access Journals (Sweden)

    Amy G. Briggs

    2016-12-01

    Full Text Available The goal of our study was to track changes in student understanding of the central dogma of molecular biology before and after taking a genetics course. Concept maps require the ability to synthesize new information into existing knowledge frameworks, and so the hypothesis guiding this study was that student performance on concept maps reveals specific central dogma misconceptions gained, lost, and retained by students. Students in a genetics course completed pre- and posttest concept mapping tasks using terms related to the central dogma. Student maps increased in complexity and validity, indicating learning gains in both content and complexity of understanding. Changes in each of the 351 possible connections in the mapping task were tracked for each student. Our students did not retain much about the central dogma from their introductory biology courses, but they did move to more advanced levels of understanding by the end of the genetics course. The information they retained from their introductory courses focused on structural components (e.g., protein is made of amino acids and not on overall mechanistic components (e.g., DNA comes before RNA, the ribosome makes protein. Students made the greatest gains in connections related to transcription, and they resolved the most prior misconceptions about translation. These concept-mapping tasks revealed that students are able to correct prior misconceptions about the central dogma during an intermediate-level genetics course. From these results, educators can design new classroom interventions to target those aspects of this foundational principle with which students have the most trouble.

  11. Expanding the global network of protected areas to save the imperiled mediterranean biome.

    Science.gov (United States)

    Underwood, Emma C; Klausmeyer, Kirk R; Cox, Robin L; Busby, Sylvia M; Morrison, Scott A; Shaw, M Rebecca

    2009-02-01

    : Global goals established by the Convention on Biological Diversity stipulate that 10% of the world's ecological regions must be effectively conserved by 2010. To meet that goal for the mediterranean biome, at least 5% more land must be formally protected over the next few years. Although global assessments identify the mediterranean biome as a priority, without biologically meaningful analysis units, finer-resolution data, and corresponding prioritization analysis, future conservation investments could lead to more area being protected without increasing the representation of unique mediterranean ecosystems. We used standardized analysis units and six potential natural vegetation types stratified by 3 elevation zones in a global gap analysis that systematically explored conservation priorities across the mediterranean biome. The highest levels of protection were in Australia, South Africa, and California-Baja California (from 9-11%), and the lowest levels of protection were in Chile and the mediterranean Basin (biome only one of the six vegetation types--mediterranean shrubland--exceeded 10% protection. The remaining vegetation types--grassland, scrub, succulent dominated, woodland, and forest--each had biome, we identified biodiversity assemblages with 30% conversion and suggest that these assemblages be elevated to high-priority status in future conservation efforts.

  12. FIFE data analysis: Testing BIOME-BGC predictions for grasslands

    Science.gov (United States)

    Hunt, E. Raymond, Jr.

    1994-01-01

    The First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) was conducted in a 15 km by 15 km research area located 8 km south of Manhattan, Kansas. The site consists primarily of native tallgrass prairie mixed with gallery oak forests and croplands. The objectives of FIFE are to better understand the role of biology in controlling the interactions between the land and the atmosphere, and to determine the value of remotely sensed data for estimating climatological parameters. The goals of FIFE are twofold: the upscale integration of models, and algorithm development for satellite remote sensing. The specific objectives of the field campaigns carried out in 1987 and 1989 were the simultaneous acquisition of satellite, atmospheric, and surface data; and the understanding of the processes controlling surface energy and mass exchange. Collected data were used to study the dynamics of various ecosystem processes (photosynthesis, evaporation and transpiration, autotrophic and heterotrophic respiration, etc.). Modelling terrestrial ecosystems at scales larger than that of a homogeneous plot led to the development of simple, generalized models of biogeochemical cycles that can be accurately applied to different biomes through the use of remotely sensed data. A model was developed called BIOME-BGC (for BioGeochemical Cycles) from a coniferous forest ecosystem model, FOREST-BGC, where a biome is considered a combination of a life forms in a specified climate. A predominately C4-photosynthetic grassland is probably the most different from a coniferous forest possible, hence the FIFE site was an excellent study area for testing BIOME-BGC. The transition from an essentially one-dimensional calculation to three-dimensional, landscape scale simulations requires the introduction of such factors as meteorology, climatology, and geomorphology. By using remotely sensed geographic information data for important model inputs, process

  13. Himalayan uplift shaped biomes in Miocene temperate Asia: evidence from leguminous Caragana

    Science.gov (United States)

    Ming-Li Zhang; Xiao-Guo Xiang; Juan-Juan Xue; Stewart C. Sanderson; Peter W. Fritsch

    2016-01-01

    Caragana, with distinctive variation in leaf and rachis characters, exhibits three centers of geographic distribution, i.e., Central Asia, the Qinghai-Tibetan Plateau (QTP), and East Asia, corresponding to distinct biomes. Because Caragana species are often ecologically dominant components of the vegetation in these regions, it is regarded as a key taxon for...

  14. Biological oscillations for learning walking coordination: dynamic recurrent neural network functionally models physiological central pattern generator.

    Science.gov (United States)

    Hoellinger, Thomas; Petieau, Mathieu; Duvinage, Matthieu; Castermans, Thierry; Seetharaman, Karthik; Cebolla, Ana-Maria; Bengoetxea, Ana; Ivanenko, Yuri; Dan, Bernard; Cheron, Guy

    2013-01-01

    The existence of dedicated neuronal modules such as those organized in the cerebral cortex, thalamus, basal ganglia, cerebellum, or spinal cord raises the question of how these functional modules are coordinated for appropriate motor behavior. Study of human locomotion offers an interesting field for addressing this central question. The coordination of the elevation of the 3 leg segments under a planar covariation rule (Borghese et al., 1996) was recently modeled (Barliya et al., 2009) by phase-adjusted simple oscillators shedding new light on the understanding of the central pattern generator (CPG) processing relevant oscillation signals. We describe the use of a dynamic recurrent neural network (DRNN) mimicking the natural oscillatory behavior of human locomotion for reproducing the planar covariation rule in both legs at different walking speeds. Neural network learning was based on sinusoid signals integrating frequency and amplitude features of the first three harmonics of the sagittal elevation angles of the thigh, shank, and foot of each lower limb. We verified the biological plausibility of the neural networks. Best results were obtained with oscillations extracted from the first three harmonics in comparison to oscillations outside the harmonic frequency peaks. Physiological replication steadily increased with the number of neuronal units from 1 to 80, where similarity index reached 0.99. Analysis of synaptic weighting showed that the proportion of inhibitory connections consistently increased with the number of neuronal units in the DRNN. This emerging property in the artificial neural networks resonates with recent advances in neurophysiology of inhibitory neurons that are involved in central nervous system oscillatory activities. The main message of this study is that this type of DRNN may offer a useful model of physiological central pattern generator for gaining insights in basic research and developing clinical applications.

  15. Central Dog-ma Disease Detectives: A Molecular Biology Inquiry Activity for Undergraduates

    Science.gov (United States)

    Quan, T. K.; Yuh, P.; Black, F.

    2010-12-01

    The Minority Access to Research Careers (MARC) and Minority Biomedical Research Support (MBRS) are programs at the University of California at Santa Cruz designed to support minority undergraduate students majoring in the sciences. Each summer MARC/MBRS sponsors a Summer Institute that involves week long "rotations" with different faculty mentors. In 2008, the Center for Adaptive Optics (CfAO) Professional Development Program (PDP) was responsible for overseeing one week of the Summer Institute, and designed it to be a Biomedical Short Course. As part of this short course, we designed a four-hour activity in which students collected their own data and explored relationships between the basic biomolecules DNA, RNA, and protein. The goal was to have the students use experimental data to support their explanation of the "Central Dogma" of molecular biology. Here we describe details of our activity and provide a post-teaching reflection on its success.

  16. Changes in forest productivity across Alaska consistent with biome shift

    Science.gov (United States)

    Peter S.A. Beck; Glenn P. Juday; Claire Alix; Valerie A. Barber; Stephen E. Winslow; Emily E. Sousa; Patricia Heiser; James D. Herriges; Scott J. Goetz

    2011-01-01

    Global vegetation models predict that boreal forests are particularly sensitive to a biome shift during the 21st century. This shift would manifest itself first at the biome's margins, with evergreen forest expanding into current tundra while being replaced by grasslands or temperate forest at the biome's southern edge. We evaluated changes in forest...

  17. Trends in biological activity research of wild-growing aromatic plants from Central Balkans

    Directory of Open Access Journals (Sweden)

    Džamić, A.M.

    2016-12-01

    Full Text Available Flowering plants consists of more than 300.000 species around the world, out of which a small percentage has been sufficiently investigated from phytochemical and biological activity aspects. Plant diversity of the Balkans is very rich, but still poorly investigated. The aim of this paper is survey of current status and trends in research of wild-growing aromatic plants from Central Balkans. Many aromatic plants are investigated from morphological, physiological, ecological, systematic and phytochemical aspects. However, traditionally used medicinal and aromatic plants can also be considered from applicative aspects, concerning their health effects, and from wide range of usage in cosmetics, and as food, agrochemical and pharmaceutical products. In order to achieve all planned objectives, following methodology has been applied: field research, taxonomic authentication and, comparative biologically assayed phytochemical investigations. The total herbal extracts, postdistillation waste (deodorized extracts, essential oils and individual compounds of some autochthonous plants have been considered as potential source of antibacterial, antifungal, anti-biofilm, antioxidant and cytotoxic agents. In this manuscript, composition of essential oils and extracts were evaluated in a number of species, from the Apiaceae, Lamiaceae, Rosaceae and Asteraceae families. Extracts which were rich in phenols mostly of flavonoids, often showed high antioxidant potential. Also, phenolic compounds identified in essential oils and extracts were mostly responsible for expected antimicrobial activity. Current worldwide demand is to reduce or, if possible, eliminate chemically synthesized food additives. Plant-produced compounds are becoming of interest as a source of more effective and safe substances than synthetically produced antimicrobial agents (as inhibitors, growth reducers or even inactivators that control growth of microorganisms. Many different pathogens have

  18. A logic-based dynamic modeling approach to explicate the evolution of the central dogma of molecular biology.

    Science.gov (United States)

    Jafari, Mohieddin; Ansari-Pour, Naser; Azimzadeh, Sadegh; Mirzaie, Mehdi

    It is nearly half a century past the age of the introduction of the Central Dogma (CD) of molecular biology. This biological axiom has been developed and currently appears to be all the more complex. In this study, we modified CD by adding further species to the CD information flow and mathematically expressed CD within a dynamic framework by using Boolean network based on its present-day and 1965 editions. We show that the enhancement of the Dogma not only now entails a higher level of complexity, but it also shows a higher level of robustness, thus far more consistent with the nature of biological systems. Using this mathematical modeling approach, we put forward a logic-based expression of our conceptual view of molecular biology. Finally, we show that such biological concepts can be converted into dynamic mathematical models using a logic-based approach and thus may be useful as a framework for improving static conceptual models in biology.

  19. On coupling global biome models with climate models

    International Nuclear Information System (INIS)

    Claussen, M.

    1994-01-01

    The BIOME model of Prentice et al. (1992), which predicts global vegetation patterns in equilibrium with climate, is coupled with the ECHAM climate model of the Max-Planck-Institut fuer Meteorologie, Hamburg. It is found that incorporation of the BIOME model into ECHAM, regardless at which frequency, does not enhance the simulated climate variability, expressed in terms of differences between global vegetation patterns. Strongest changes are seen only between the initial biome distribution and the biome distribution computed after the first simulation period, provided that the climate-biome model is started from a biome distribution that resembles the present-day distribution. After the first simulation period, there is no significant shrinking, expanding, or shifting of biomes. Likewise, no trend is seen in global averages of land-surface parameters and climate variables. (orig.)

  20. Eastern deciduous forest biome progress report, September 1, 1975--August 31, 1976

    International Nuclear Information System (INIS)

    Burgess, R.L.; Tarr, N.E.

    1978-09-01

    The report concentrates on the six projects as well as results from synthesis activities at the Lake George, Lake Wingra, and Oak Ridge sites. The centralized analysis and modeling component and the Eastern Decidious Forest Biome Information Center progress during the past year are also addressed. The project on belowground dynamics of ecosystems is investigating the allocation of phytosynthetic products into fixed or labile storage pools. Root sampling, radioactive tracer techniques, and biochemical analyses are leading to an understanding of complete tree physioogy requisite for interpreting forest growth in different environments. The Role of Consumers project has begun to document the regulatory role of heterotrophs in an array of ecosystem niches. Decomposition of woody substrates, studies of the contribution of canopy and litter arthropods to material processing, and the flow and remineralization of phosphorus in lake systems are leading to a comprehensive understanding of the role of consumer organisms in ecosystem function. The Microdynamics of Detritus project continues its investigations of carbon and nitrogen dynamics in freshwater lakes. Examination of potential pathways of detritus processing is illustrating the parts that physical and biological processes play in the breakdown of organic materials

  1. Biome Is Where the Art Is

    Science.gov (United States)

    Gooden, Kelly

    2005-01-01

    The author is surprised every year when fifth-grade students react to the study of biomes as if they've never given any thought to the differences across parts of the world. Sure, they've all heard of the tropical rain forest and the desert, but it seems as though they think the rest of the world is just some undefined area with climate, animals,…

  2. Microhabitat and biology of Sphaerium striatinum in a central New York stream

    Science.gov (United States)

    Dittman, Dawn E.; Johnson, James H.; Nack, Christopher C.

    2018-01-01

    In many lotic systems, drastic declines in freshwater bivalve populations, including fingernail clams (Sphaeriidae), have created concerns about biodiversity and future ecosystem services. We examined the local occurrence of the historically common fingernail clam, Sphaerium striatinum, in a central New York stream. We sampled the density of sphaeriids and measured the associated habitat variables (substrate, depth, water flow) to test within-stream multivariate benthic microhabitat association. Size distribution, density, and diel feeding periodicity were measured as focal aspects of fingernail clam biology and ecology. S. striatinum tended to be found in microhabitats that had harder substrates and faster flow. The Labrador Creek fingernail clam local population had positive indicators (size distribution, density). There was significant diel periodicity in feeding behavior. The clams fed most actively during the 0400–0800 h periods. This kind of behavioral periodicity can indicate a significant ecological interaction between predators and bivalve prey. Increased understanding of the behavioral ecology of small native freshwater bivalves in an unimpacted headwater stream is a fundamental building block for development of overall ecological conservation goals for freshwater bivalves and their lotic habitats.

  3. Unstable genes unstable mind: beyond the central dogma of molecular biology.

    Science.gov (United States)

    Hegde, Mahabaleshwar V; Saraph, Arundhati A

    2011-08-01

    Schizophrenia has a polygenic mode of inheritance and an estimated heritability of over 80%, but success in understanding its genetic underpinnings to date has been modest. Unlike in trinucleotide neurodegenerative disorders, the phenomenon of genetic anticipation observed in schizophrenia or bipolar disorder has not been explained. For the first time, we provide a plausible molecular explanation of genetic anticipation and pathophysiology of schizophrenia, at least in part, with supporting evidence. We postulate that abnormally increased numbers of CAG repeats in many genes being expressed in the brain, coding for glutamine, cumulatively press for higher demand of glutamine in the respective brain cells, resulting in a metabolic crisis and dysregulation of the glutamate-glutamine cycle. This can adversely affect the functioning of both glutamate and GABA receptors, which are known to be involved in psychosis, and may also affect glutathione levels, increasing oxidative stress. The resulting psychosis (gain in function), originating from unstable genes, is described as an effect "beyond the central dogma of molecular biology". The hypothesis explains genetic anticipation, as further expansions in subsequent generations may result in increased severity and earlier occurrence. Many other well described findings provide proof of concept. This is a testable hypothesis, does not deny any known facts and opens up new avenues of research. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Evolution of physical and biological characteristics of mesoscale eddy in north-central Red Sea

    KAUST Repository

    Zarokanellos, Nikolaos

    2015-04-01

    Eddies appear to be important to both the physical and biogeochemical dynamics of the Red Sea. Numerical simulations of physical dynamics and remote sensing studies of chlorophyll concentration and sea surface height in the Red Sea indicate their importance to the upper portions of the sea (Raitsos et al., 2013; Yao et al., 2014; Zhan et al., 2014). Despite their apparent importance, process studies of these eddies have been lacking. In March 2013 we began an extended observational study of the north-central Red Sea (NCRS) where anticyclonic eddies have been observed. The study began with a ship-based characterization of the eddy and was followed by a three-month observational time series using an autonomous glider equipped with a CTD, oxygen sensor, and optical sensors for chlorophyll, CDOM and optical backscatter. The ship-based study captured an initial snapshot of an anticyclonic eddy and it\\'s associated biological and bio-optical distributions. Initially, chlorophyll distributions tended to mirror the density distribution, with deeper isopycnals and chlorophyll maximum depth in the anticyclonic eddy center. The anticyclone eddy in March had an along basin diameter of 150 km, penetrated vertically less than 150 m and elevated near surface chlorophyll concentrations appeared along its outer boundary. The shallowing of the pycnocline of the outer boundaries of the anticyclone eddy on March may elevate nutrients into the lower euphotic zone, contributing to phytoplankton productivity and biomass within the eddy. This eddy contains most of the kinetic energy of the region with the maximum velocities up to 30 - 35 cm/s. The eddy appeared to interact with the coastal reefs where exchange particulate and dissolved matter may occur. The autonomous glider provided the spring-to-summer progression of the system with increasing stratification, shallowing of the subsurface chlorophyll maximum, and fluctuations in the position and intensity of the eddy. Our glider effort

  5. Software quality assurance and software safety in the Biomed Control System

    International Nuclear Information System (INIS)

    Singh, R.P.; Chu, W.T.; Ludewigt, B.A.; Marks, K.M.; Nyman, M.A.; Renner, T.R.; Stradtner, R.

    1989-01-01

    The Biomed Control System is a hardware/software system used for the delivery, measurement and monitoring of heavy-ion beams in the patient treatment and biology experiment rooms in the Bevalac at the Lawrence Berkeley Laboratory (LBL). This paper describes some aspects of this system including historical background philosophy, configuration management, hardware features that facilitate software testing, software testing procedures, the release of new software quality assurance, safety and operator monitoring. 3 refs

  6. Anthropogenic Biomes of the World, Version 2: 1700

    Data.gov (United States)

    National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 1700 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

  7. Anthropogenic Biomes of the World, Version 2: 1900

    Data.gov (United States)

    National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 1900 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

  8. Anthropogenic Biomes of the World, Version 2: 1800

    Data.gov (United States)

    National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 1800 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

  9. Anthropogenic Biomes of the World, Version 2: 2000

    Data.gov (United States)

    National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 2000 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

  10. Comparative patterns of plant invasions in the Mediterranean biome.

    Science.gov (United States)

    Arianoutsou, Margarita; Delipetrou, Pinelopi; Vilà, Montserrat; Dimitrakopoulos, Panayiotis G; Celesti-Grapow, Laura; Wardell-Johnson, Grant; Henderson, Lesley; Fuentes, Nicol; Ugarte-Mendes, Eduardo; Rundel, Philip W

    2013-01-01

    The objective of this work was to compare and contrast the patterns of alien plant invasions in the world's five mediterranean-climate regions (MCRs). We expected landscape age and disturbance history to have bearing on levels of invasion. We assembled a database on naturalized alien plant taxa occurring in natural and semi-natural terrestrial habitats of all five regions (specifically Spain, Italy, Greece and Cyprus from the Mediterranean Basin, California, central Chile, the Cape Region of South Africa and Southwestern - SW Australia). We used multivariate (hierarchical clustering and NMDS ordination) trait and habitat analysis to compare characteristics of regions, taxa and habitats across the mediterranean biome. Our database included 1627 naturalized species with an overall low taxonomic similarity among the five MCRs. Herbaceous perennials were the most frequent taxa, with SW Australia exhibiting both the highest numbers of naturalized species and the highest taxonomic similarity (homogenization) among habitats, and the Mediterranean Basin the lowest. Low stress and highly disturbed habitats had the highest frequency of invasion and homogenization in all regions, and high natural stress habitats the lowest, while taxonomic similarity was higher among different habitats in each region than among regions. Our analysis is the first to describe patterns of species characteristics and habitat vulnerability for a single biome. We have shown that a broad niche (i.e. more than one habitat) is typical of naturalized plant species, regardless of their geographical area of origin, leading to potential for high homogenization within each region. Habitats of the Mediterranean Basin are apparently the most resistant to plant invasion, possibly because their landscapes are generally of relatively recent origin, but with a more gradual exposure to human intervention over a longer period.

  11. La filatelia biomédica

    OpenAIRE

    Emilio J.A. Roldán; Claudio Zuckerberg

    2011-01-01

    La temática biomédica es un capítulo extendido de la filatelia o coleccionismo de sellos postales. Inaugura la temática la imagen de la diosa Hygeia, en un sello de la isla Nevis de 1861. Los primeros médicos retratados en una estampilla son tres constitucionalistas americanos, en un ejemplar de 1869, pero recién en 1937 aparecen médicos holandeses en reconocimiento específico de sus aportes a la salud. En la Argentina la primera estampilla que oficialmente se ocupa del tema es de 1944, en ay...

  12. 2008 Co2 Assimilation in Plants: Genome to Biome Gordon Research Conference - August 17-22

    Energy Technology Data Exchange (ETDEWEB)

    James V. Maroney

    2009-08-12

    Formerly entitled 'CO2 Fixation and Metabolism in Green Plants', this long-standing Gordon Research Conference has been held on a triennial basis since 1976. In 1990 the participants decided to alternate between sites in the U.S. and outside the U.S. The 2005 conference was held in Europe at the Centre Paul Langevin in Aussois, France, so the 2008 conference returns to a U.S. site - the University of New England in Biddeford, Maine. The 2008 conference covers basic plant research related to photosynthesis and the subsequent regulation and engineering of carbon assimilation. Approaches that range from post-genomic technologies and systems biology, through to fundamental biochemistry, physiology and molecular biology are integrated within ecological and agronomic contexts. As such, the meeting provides the rare opportunity of a single venue for discussing all aspects of the 'carbon-side' of photosynthesis - from genome to biome. The 2008 conference will include an emphasis on the central role of carbon assimilation by plants for developing new sources of bioenergy and for achieving a carbon-neutral planet. A special characteristic of this conference is its 'intimacy' with approximately 110 conferees, ranging from beginning graduate students and postdoctoral associates to leading senior plant scientists, engaged in open and forward-thinking discussions in an informal, friendly setting. With extended time devoted to discussion, and the encouragement to challenge dogma, it is unlike other meetings in the U.S. or abroad. Another novel feature of the conference is a session devoted to the latest 'hot off the press' findings by both established and early career scientists, picked from the abstracts. Together with an expanded poster discussion in the evening sessions, this session provides an opportunity for early career scientists to present interesting new data and to 'test drive' hypotheses in a collegial atmosphere.

  13. Environmental history of the dry forest biome of Guerrero, Mexico, and human impact during the last c. 2700 years

    NARCIS (Netherlands)

    Berrio, J.C.; Hooghiemstra, H.; van Geel, B.; Ludlow-Wiegers, B.

    2006-01-01

    Two lake sediment cores from Madre del Sur mountain range, Guerrero State, west-central Mexico were studied to examine the past dynamics of the dry forest biome. Pollen, spores of coprophilous fungi, cyanobacteria and lithological changes are presented. The 390-cm Tixtla core (17°30′N, 99°24′W, 1400

  14. Biological restoration of central nervous system architecture and function: part 3-stem cell- and cell-based applications and realities in the biological management of central nervous system disorders: traumatic, vascular, and epilepsy disorders.

    Science.gov (United States)

    Farin, Azadeh; Liu, Charles Y; Langmoen, Iver A; Apuzzo, Michael L J

    2009-11-01

    STEM CELL THERAPY has emerged as a promising novel therapeutic endeavor for traumatic brain injury, spinal cord injury, stroke, and epilepsy in experimental studies. A few preliminary clinical trials have further supported its safety and early efficacy after transplantation into humans. Although not yet clinically available for central nervous system disorders, stem cell technology is expected to evolve into one of the most powerful tools in the biological management of complex central nervous system disorders, many of which currently have limited treatment modalities. The identification of stem cells, discovery of neurogenesis, and application of stem cells to treat central nervous system disorders represent a dramatic evolution and expansion of the neurosurgeon's capabilities into the neurorestoration and neuroregeneration realms. In Part 3 of a 5-part series on stem cells, we discuss the theory, experimental evidence, and clinical data pertaining to the use of stem cells for the treatment of traumatic, vascular, and epileptic disorders.

  15. The large carpenter bees of central Saudi Arabia, with notes on the biology of Xylocopa sulcatipes Maa (Hymenoptera, Apidae, Xylocopinae

    Directory of Open Access Journals (Sweden)

    Mohammed Hannan

    2012-06-01

    Full Text Available The large carpenter bees (Xylocopinae, Xylocopa Latreille occurring in central Saudi Arabia are reviewed. Two species are recognized in the fauna, Xylocopa (Koptortosoma aestuans (Linnaeus and X. (Ctenoxylocopa sulcatipes Maa. Diagnoses for and keys to the species of these prominent components of the central Saudi Arabian bee fauna are provided to aid their identification by pollination researchers active in the region. Females and males of both species are figured and biological notes provided for X. sulcatipes. Notes on the nesting biology and ecology of X. sulcatipes are appended. As in studies for this species from elsewhere, nests were found in dried stems of Calotropis procera (Aiton (Asclepiadaceae and Phoenix dactylifera L. (Arecaceae.

  16. Nesting biology of four species of Trypoxylon (Trypargilum (Hymenoptera: Crabronidae in Chaco Serrano woodland, Central Argentina

    Directory of Open Access Journals (Sweden)

    Mariana L Musicante

    2010-12-01

    Full Text Available Trypoxylon (Trypargilum (Crabronidae wasps are solitary spider predators that can build their nests in artificial trap-nests, which enables study of their nesting architecture and biology. Twenty traps (each containing 15-30 internodes of cane were placed in each of nine sites of Chaco Serrano Woodland in Central Argentina (Córdoba in October 2005, and were recovered in June 2006. We obtained 91 nests of four species of Trypoxylon (Trypargilum. In the laboratory, each Trypoxylon nest was sectioned longitudinally to study its architecture. The number of brood cells was counted, and the occurrence and length of vestibular and intercalary cells and the pre-closing plug space were recorded. We measured the diameter of the cane entrance, total length of the nest, length of each brood cell, maximum thickness of mud partitions and closing plug thickness. We also recorded the cell contents: the wasps, their natural enemies and the prey spiders. Mortality was assessed and the sex ratio calculated for each species. Finally, the nests were examined to help clarify the function of the vestibular cell. The nest architecture was similar in the four species, with linear brood cells located one after the other separated by mud partitions, as in other species of the subgenus Trypargilum. Forty-eight percent of the nests had vestibular cells, but only two had intercalary cells. The thickness of the mud partitions and the length of the brood cells differed among species and were related to the size of the emerged wasp. The diameter of the nest entrance was directly related to the average length of the fore-tibia. Sex ratios of all species did not deviate from 0.5. Mortality due to parasitoids (Eulophidae; Melittobia sp. was similar among species, while the mortality due to cuckoo wasps (Chrysididae in T. lactitarse was higher than in the other species. The presence of vestibular cells was not related either to the mortality due to natural enemies or to the

  17. Nesting biology of four species of Trypoxylon (Trypargilum (Hymenoptera: Crabronidae in Chaco Serrano woodland, Central Argentina

    Directory of Open Access Journals (Sweden)

    Mariana L Musicante

    2010-12-01

    Full Text Available Trypoxylon (Trypargilum (Crabronidae wasps are solitary spider predators that can build their nests in artificial trap-nests, which enables study of their nesting architecture and biology. Twenty traps (each containing 15-30 internodes of cane were placed in each of nine sites of Chaco Serrano Woodland in Central Argentina (Córdoba in October 2005, and were recovered in June 2006. We obtained 91 nests of four species of Trypoxylon (Trypargilum. In the laboratory, each Trypoxylon nest was sectioned longitudinally to study its architecture. The number of brood cells was counted, and the occurrence and length of vestibular and intercalary cells and the pre-closing plug space were recorded. We measured the diameter of the cane entrance, total length of the nest, length of each brood cell, maximum thickness of mud partitions and closing plug thickness. We also recorded the cell contents: the wasps, their natural enemies and the prey spiders. Mortality was assessed and the sex ratio calculated for each species. Finally, the nests were examined to help clarify the function of the vestibular cell. The nest architecture was similar in the four species, with linear brood cells located one after the other separated by mud partitions, as in other species of the subgenus Trypargilum. Forty-eight percent of the nests had vestibular cells, but only two had intercalary cells. The thickness of the mud partitions and the length of the brood cells differed among species and were related to the size of the emerged wasp. The diameter of the nest entrance was directly related to the average length of the fore-tibia. Sex ratios of all species did not deviate from 0.5. Mortality due to parasitoids (Eulophidae; Melittobia sp. was similar among species, while the mortality due to cuckoo wasps (Chrysididae in T. lactitarse was higher than in the other species. The presence of vestibular cells was not related either to the mortality due to natural enemies or to the

  18. La filatelia biomédica

    Directory of Open Access Journals (Sweden)

    Emilio J.A. Roldán

    2011-02-01

    Full Text Available La temática biomédica es un capítulo extendido de la filatelia o coleccionismo de sellos postales. Inaugura la temática la imagen de la diosa Hygeia, en un sello de la isla Nevis de 1861. Los primeros médicos retratados en una estampilla son tres constitucionalistas americanos, en un ejemplar de 1869, pero recién en 1937 aparecen médicos holandeses en reconocimiento específico de sus aportes a la salud. En la Argentina la primera estampilla que oficialmente se ocupa del tema es de 1944, en ayuda de las víctimas del terremoto de San Juan. Florentino Ameghino es el primer científico incluido en 1954, y en 1967 se edita un sello conmemorativo de la Dra. Cecilia Grierson. La filatelia argentina luego reconoce varios de nuestros científicos y médicos, congresos, universidades, campañas sanitarias, temas de odontología, farmacia, enfermería y otros, generando un amplio material filatélico en reconocimiento del valor social que la ciencia biomédica argentina ha logrado en el contexto propio e internacional. Posiblemente sea un científico, el Dr. Bernardo Houssay, uno de los argentinos más veces editado en distintos sellos postales de la filatelia mundial.

  19. A logic-based dynamic modeling approach to explicate the evolution of the central dogma of molecular biology.

    Directory of Open Access Journals (Sweden)

    Mohieddin Jafari

    Full Text Available It is nearly half a century past the age of the introduction of the Central Dogma (CD of molecular biology. This biological axiom has been developed and currently appears to be all the more complex. In this study, we modified CD by adding further species to the CD information flow and mathematically expressed CD within a dynamic framework by using Boolean network based on its present-day and 1965 editions. We show that the enhancement of the Dogma not only now entails a higher level of complexity, but it also shows a higher level of robustness, thus far more consistent with the nature of biological systems. Using this mathematical modeling approach, we put forward a logic-based expression of our conceptual view of molecular biology. Finally, we show that such biological concepts can be converted into dynamic mathematical models using a logic-based approach and thus may be useful as a framework for improving static conceptual models in biology.

  20. Changes in forest productivity across Alaska consistent with biome shift.

    Science.gov (United States)

    Beck, Pieter S A; Juday, Glenn P; Alix, Claire; Barber, Valerie A; Winslow, Stephen E; Sousa, Emily E; Heiser, Patricia; Herriges, James D; Goetz, Scott J

    2011-04-01

    Global vegetation models predict that boreal forests are particularly sensitive to a biome shift during the 21st century. This shift would manifest itself first at the biome's margins, with evergreen forest expanding into current tundra while being replaced by grasslands or temperate forest at the biome's southern edge. We evaluated changes in forest productivity since 1982 across boreal Alaska by linking satellite estimates of primary productivity and a large tree-ring data set. Trends in both records show consistent growth increases at the boreal-tundra ecotones that contrast with drought-induced productivity declines throughout interior Alaska. These patterns support the hypothesized effects of an initiating biome shift. Ultimately, tree dispersal rates, habitat availability and the rate of future climate change, and how it changes disturbance regimes, are expected to determine where the boreal biome will undergo a gradual geographic range shift, and where a more rapid decline. © 2011 Blackwell Publishing Ltd/CNRS.

  1. Climate-biomes, pedo-biomes and pyro-biomes: which world view explains the tropical forest - savanna boundary in South America?

    Science.gov (United States)

    Langan, Liam; Higgins, Steven; Scheiter, Simon

    2015-04-01

    Elucidating the drivers of broad vegetation formations improves our understanding of earth system functioning. The biome, defined primarily by the dominance of a particular growth strategy, is commonly employed to group vegetation into similar units. Predicting tropical forest and savanna biome boundaries in South America has proven difficult. Process based DGVMs (Dynamic global vegetation models) are our best tool to simulate vegetation patterns, make predictions for future changes and test theory, however, many DGVMs fail to accurately simulate the spatial distribution or indeed presence of the South American savanna biome which can result in large differences in modelled ecosystem structural properties. Evidence suggests fire plays a significant role in mediating these forest and savanna biome boundaries, however, fire alone does not appear to be sufficient to predict these boundaries in South America using DGVMs hinting at the presence of one or more missing environmental factors. We hypothesise that soil depth, which affects plant available water by determining maximum storage potential and influences temporal availability, may be one of these missing environmental factors. To test our hypothesis we use a novel vegetation model, the aDGVM2. This model has been specifically designed to allow plant trait strategies, constrained by trade-offs between traits, evolve based on the abiotic and biotic conditions where the resulting community trait suites are emergent properties of model dynamics. Furthermore it considers root biomass in multiple soil layers and therefore allows the consideration of alternative rooting strategies, which in turn allows us to explore in more detail the role of soil hydraulic factors in controlling biome boundary distributions. We find that changes in soil depth, interacting with fire, affect the relative dominance of tree and grass strategies and thus the presence and spatial distribution of forest and savanna biomes in South America

  2. Biological characteristics of Central Indian Basin waters during the southern summer

    Digital Repository Service at National Institute of Oceanography (India)

    Matondkar, S.G.P.; Nair, K.K.C.; Ansari, Z.A.

    Phytoplankton biomass, taxonomy, primary productivity, and photosynthetically available radiation (PAR) were studied as part of baseline data collection for prospective nodule mining in the Central Indian Basin during the ORV Sagar Kanya cruise SK...

  3. Stream and Aquifer Biology of South-Central Texas - A Literature Review, 1973-97

    National Research Council Canada - National Science Library

    Ourso, Robert T; Hornig, C. E

    2000-01-01

    This report summarizes in table format 32 aquatic vertebrate (primarily fish), 54 aquatic invertebrate, and 13 aquatic plant studies available for the area of the South-Central Texas study unit of the U.S...

  4. Biological Flora of Central Europe: Viola elatior, V. pumila and V. stagnina

    Czech Academy of Sciences Publication Activity Database

    Eckstein, R. L.; Hölzel, N.; Danihelka, Jiří

    2006-01-01

    Roč. 8, - (2006), s. 45-66 ISSN 1433-8319 Institutional research plan: CEZ:AV0Z60050516 Keywords : ecology * species biology * Viola persicifolia Subject RIV: EF - Botanics Impact factor: 2.905, year: 2006

  5. Biología reproductiva del águila Geranoaetus melanoleucus (Aves: Accipitridae) en Chile central Breeding biology of the black-chested eagle Geranoaetus melanoleucus (Aves: Accipitridae) in central Chile

    OpenAIRE

    EDUARDO F. PAVEZ

    2001-01-01

    Durante dos años (julio 1987­enero 1989) se estudió la biología reproductiva del águila (Geranoaetus melanoleucus) en San Carlos de Apoquindo, en Chile central. El inicio del período reproductivo se evidenció por un aumento del número de vuelos en pareja. Los cortejos incluyeron vuelos sincronizados de la pareja, capturas, transporte de material al nido y cópulas. Los traspasos de presas ocurrieron durante todo el año, aunque fuera del período reproductivo fueron escasos y forzados por la hem...

  6. Evolution of physical and biological characteristics of mesoscale eddy in north-central Red Sea

    KAUST Repository

    Zarokanellos, Nikolaos; Jones, Burton

    2015-01-01

    -central Red Sea (NCRS) where anticyclonic eddies have been observed. The study began with a ship-based characterization of the eddy and was followed by a three-month observational time series using an autonomous glider equipped with a CTD, oxygen sensor

  7. Parasites as biological tags of divergence in Central European gudgeon populations (Actinopterygii: Cyprinidae: Gobioninae)

    Czech Academy of Sciences Publication Activity Database

    Kvach, Yuriy; Ondračková, Markéta; Bryjová, Anna; Jurajda, Pavel

    2017-01-01

    Roč. 72, č. 6 (2017), s. 671-679 ISSN 0006-3088 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : Gobio * Romanogobio * sympatric species * parasite community * biological tags Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 0.759, year: 2016

  8. Biological flora of Central Europe: Dactylorhiza sambucina (L.) Soó

    Czech Academy of Sciences Publication Activity Database

    Jersáková, J.; Traxmandlová, Iva; Ipser, Z.; Kropf, M.; Pellegrino, G.; Schatz, B.; Djordjevič, V.; Kindlmann, Pavel; Renner, S.S.

    2015-01-01

    Roč. 17, č. 4 (2015), s. 318-329 ISSN 1433-8319 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : Colour polymorphism * dormancy * ecological niche * life cycle * reproductive biology * seed germination Subject RIV: EH - Ecology, Behaviour Impact factor: 3.578, year: 2015

  9. Soil formation and soil biological properties post mining sites after coal mining in central Europe

    Czech Academy of Sciences Publication Activity Database

    Kaneda, Satoshi; Frouz, Jan; Krištůfek, Václav; Elhottová, Dana; Pižl, Václav; Starý, Josef; Háněl, Ladislav; Tajovský, Karel; Chroňáková, Alica

    2007-01-01

    Roč. 53, - (2007), s. 13 ISSN 0288-5840. [Annual Meeting Japanese Society of Soil Science and Plant Nutrition . 22.08.2007, Setagaya city] Institutional research plan: CEZ:AV0Z60660521 Keywords : soil formation * soil biological properties * post mining sites Subject RIV: EH - Ecology, Behaviour

  10. BIOME: An Ecosystem Remote Sensor Based on Imaging Interferometry

    Science.gov (United States)

    Peterson, David L.; Hammer, Philip; Smith, William H.; Lawless, James G. (Technical Monitor)

    1994-01-01

    Until recent times, optical remote sensing of ecosystem properties from space has been limited to broad band multispectral scanners such as Landsat and AVHRR. While these sensor data can be used to derive important information about ecosystem parameters, they are very limited for measuring key biogeochemical cycling parameters such as the chemical content of plant canopies. Such parameters, for example the lignin and nitrogen contents, are potentially amenable to measurements by very high spectral resolution instruments using a spectroscopic approach. Airborne sensors based on grating imaging spectrometers gave the first promise of such potential but the recent decision not to deploy the space version has left the community without many alternatives. In the past few years, advancements in high performance deep well digital sensor arrays coupled with a patented design for a two-beam interferometer has produced an entirely new design for acquiring imaging spectroscopic data at the signal to noise levels necessary for quantitatively estimating chemical composition (1000:1 at 2 microns). This design has been assembled as a laboratory instrument and the principles demonstrated for acquiring remote scenes. An airborne instrument is in production and spaceborne sensors being proposed. The instrument is extremely promising because of its low cost, lower power requirements, very low weight, simplicity (no moving parts), and high performance. For these reasons, we have called it the first instrument optimized for ecosystem studies as part of a Biological Imaging and Observation Mission to Earth (BIOME).

  11. Montane plant environments in the Fynbos Biome

    Directory of Open Access Journals (Sweden)

    B. M. Campbell

    1983-12-01

    Full Text Available Environmental data collected at 507 plots on 22 transects, and soil analytical data from 81 of these plots, have been used to describe the plant environments of the mountains in the Fynbos Biome. Two major regional gradients are recognized: a west-east gradient and a coast-interior gradient. Of particular consequence for fynbos-environment studies is the increase in the proportion of fine soil particles from west to east. At least some aspects of soil fertility also increase towards the east. The edaphic changes are paralleled by climatic changes: chiefly a decrease in the severity of summer drought towards the east. On the coast-interior gradient a major non-climatic variable in the gradient is rock cover. High rock cover is a feature of the interior ranges. Soils with organic horizons or with E horizons are a feature on the coastal mountains, but are generally lacking on the interior mountains. The other environmental gradients recognized occur on individual transects and all include edaphic variables. The rockiness-soil depth gradient, on which an increase in rockiness is associated with a decrease in soil depth and usually a decrease in clay content, tends to occur in three situations. Firstly, it is associated with local topographic variation; the shallow, rocky soils being a feature of the steeper slopes. Secondly, it is associated with the aspect gradient; the hot, dry northern aspects having shallow, rocky, less developed soils. Thirdly, it tends to be associated with the altitude-rainfall gradient: shallower soils being found at higher altitudes. It is also at higher altitudes that higher rainfall is found. Variation in oxidizable carbon is chiefly accounted for by the altitude-rainfall gradient. Whereas at a biome-wide level, aspects of soil fertility are related to soil texture, it appears that on individual transects fertility is linked to amounts of plant remains in the soil and to rainfall. Apart from these gradients, which are

  12. The Economics of Root Distributions of Terrestrial Biomes in Response to Elevated CO2

    Science.gov (United States)

    Lu, M.; Hedin, L. O. O.

    2017-12-01

    Belowground root distributions of terrestrial biomes are central to understanding soil biogeochemical processes and land carbon sink. Yet models are thus far not able to predict root distributions across plant functional groups and major biomes, limiting our ability to predict the response of land systems to elevated CO2 concentration. Of particular concern is the apparent lack of stimulation of the aboveground carbon sink despite 30% increase of atmospheric CO2 over the past half-century, and despite the clear acceleration of the land carbon sink over the same period. This apparent discrepancy in land ecosystem response has led to the proposition that changes in belowground root dynamics might be responsible for the overlooked land sink. We here present a new modeling approach for predicting the response of root biomass and soil carbon storage to increased CO2. Our approach considers the first-principle mechanisms and tradeoffs by which plants and plant roots invest carbon to gain belowground resources, in collaboration with distinct root symbioses. We allow plants to locally compete for nutrients, with the ability to allocate biomass at different depths in the soil profile. We parameterized our model using an unprecedented global dataset of root traits, and validated our biome-level predictions with a recently updated global root biomass database. Our results support the idea that plants "dig deeper" when exposed to increased CO2, and we offer an economic-based mechanism for predicting the plant root response across soil conditions, plant functional groups and major biomes. Our model also recreates the observed responses across a range of free-air CO2 enrichment experiments, including a distinct response between plants associated with ectomycorrhizal and arbuscular mycorrhizal fungi. Most broadly, our findings suggest that roots may be increasingly important in the land carbon sink, and call for a greater effort to quantify belowground responses to elevated

  13. Seven fundamental, unsolved questions in molecular biology. Cooperative storage and bi-directional transfer of biological information by nucleic acids and proteins: an alternative to "central dogma".

    Science.gov (United States)

    Biro, J C

    2004-01-01

    The Human Genome Mapping Project provided us a large amount of sequence data. However our understanding of these data did not grow proportionally, because old dogmas still set the limits of our thinking. The gene-centric, reductionistical side of molecular biology is reviewed and seven problems are formulated, each indicating the insufficiency of the "central dogma". The following is concluded and suggested: 1. Genes are located and expressed on both DNA strands; 2. Introns are the source of important biological regulation and diversity; 3. Repeats are the frame of the chromatin structure and participate in the chromatin regulation; 4. The molecular accessibility of the canonical dsDNA structure is poor; 5. The genetic code is co-evolved with the amino acids and there is a stereochemical matching between the codes andamino acids; 6. The flow of information between nucleic acids and proteins is bi-directional and reverse translation might exist; 7. Complex genetic information is always carried and stored by nucleic acids and proteins together.

  14. Using an Exploratory Internet Activity & Trivia Game to Teach Students about Biomes

    Science.gov (United States)

    Richardson, Matthew L.

    2009-01-01

    Students in life science classes need an introduction to biomes, including an introduction to the concept, key biotic and abiotic features of biomes, and geographic locations of biomes. In this activity, students in seventh- and eighth-grade science classes used a directed exploratory Internet activity to learn about biomes. The author tested…

  15. Spatial Distribution of Aboveground Carbon Stock of the Arboreal Vegetation in Brazilian Biomes of Savanna, Atlantic Forest and Semi-Arid Woodland.

    Science.gov (United States)

    Scolforo, Henrique Ferraco; Scolforo, Jose Roberto Soares; Mello, Carlos Rogerio; Mello, Jose Marcio; Ferraz Filho, Antonio Carlos

    2015-01-01

    The objective of this study was to map the spatial distribution of aboveground carbon stock (using Regression-kriging) of arboreal plants in the Atlantic Forest, Semi-arid woodland, and Savanna Biomes in Minas Gerais State, southeastern Brazil. The database used in this study was obtained from 163 forest fragments, totaling 4,146 plots of 1,000 m2 distributed in these Biomes. A geographical model for carbon stock estimation was parameterized as a function of Biome, latitude and altitude. This model was applied over the samples and the residuals generated were mapped based on geostatistical procedures, selecting the exponential semivariogram theoretical model for conducting ordinary Kriging. The aboveground carbon stock was found to have a greater concentration in the north of the State, where the largest contingent of native vegetation is located, mainly the Savanna Biome, with Wooded Savanna and Shrub Savanna phytophysiognomes. The largest weighted averages of carbon stock per hectare were found in the south-center region (48.6 Mg/ha) and in the southern part of the eastern region (48.4 Mg/ha) of Minas Gerais State, due to the greatest predominance of Atlantic Forest Biome forest fragments. The smallest weighted averages per hectare were found in the central (21.2 Mg/ha), northern (20.4 Mg/ha), and northwestern (20.7 Mg/ha) regions of Minas Gerais State, where Savanna Biome fragments are predominant, in the phytophysiognomes Wooded Savanna and Shrub Savanna.

  16. Structural characterization of vegetation in the fynbos biome

    CSIR Research Space (South Africa)

    Campbell, BM

    1981-08-01

    Full Text Available A proposed system for the standardization of descriptive terminology for structural characterization of vegetation in the Fynbos Biome is presented in tabular form. Specific applications of the system are described and illustrations of some...

  17. Forest resilience to drought varies across biomes.

    Science.gov (United States)

    Gazol, Antonio; Camarero, Jesus Julio; Vicente-Serrano, Sergio M; Sánchez-Salguero, Raúl; Gutiérrez, Emilia; de Luis, Martin; Sangüesa-Barreda, Gabriel; Novak, Klemen; Rozas, Vicente; Tíscar, Pedro A; Linares, Juan C; Martín-Hernández, Natalia; Martínez Del Castillo, Edurne; Ribas, Montse; García-González, Ignacio; Silla, Fernando; Camisón, Alvaro; Génova, Mar; Olano, José M; Longares, Luis A; Hevia, Andrea; Tomás-Burguera, Miquel; Galván, J Diego

    2018-05-01

    Forecasted increase drought frequency and severity may drive worldwide declines in forest productivity. Species-level responses to a drier world are likely to be influenced by their functional traits. Here, we analyse forest resilience to drought using an extensive network of tree-ring width data and satellite imagery. We compiled proxies of forest growth and productivity (TRWi, absolutely dated ring-width indices; NDVI, Normalized Difference Vegetation Index) for 11 tree species and 502 forests in Spain corresponding to Mediterranean, temperate, and continental biomes. Four different components of forest resilience to drought were calculated based on TRWi and NDVI data before, during, and after four major droughts (1986, 1994-1995, 1999, and 2005), and pointed out that TRWi data were more sensitive metrics of forest resilience to drought than NDVI data. Resilience was related to both drought severity and forest composition. Evergreen gymnosperms dominating semi-arid Mediterranean forests showed the lowest resistance to drought, but higher recovery than deciduous angiosperms dominating humid temperate forests. Moreover, semi-arid gymnosperm forests presented a negative temporal trend in the resistance to drought, but this pattern was absent in continental and temperate forests. Although gymnosperms in dry Mediterranean forests showed a faster recovery after drought, their recovery potential could be constrained if droughts become more frequent. Conversely, angiosperms and gymnosperms inhabiting temperate and continental sites might have problems to recover after more intense droughts since they resist drought but are less able to recover afterwards. © 2018 John Wiley & Sons Ltd.

  18. Pollen-based biome reconstructions for Latin America at 0, 6000 and 18 000 radiocarbon years

    Science.gov (United States)

    Marchant, R.; Harrison, S.P.; Hooghiemstra, H.; Markgraf, Vera; Van Boxel, J. H.; Ager, T.; Almeida, L.; Anderson, R.; Baied, C.; Behling, H.; Berrio, J.C.; Burbridge, R.; Bjorck, S.; Byrne, R.; Bush, M.B.; Cleef, A.M.; Duivenvoorden, J.F.; Flenley, J.R.; De Oliveira, P.; Van Geel, B.; Graf, K.J.; Gosling, W.D.; Harbele, S.; Van Der Hammen, T.; Hansen, B.C.S.; Horn, S.P.; Islebe, G.A.; Kuhry, P.; Ledru, M.-P.; Mayle, F.E.; Leyden, B.W.; Lozano-Garcia, S.; Melief, A.B.M.; Moreno, P.; Moar, N.T.; Prieto, A.; Van Reenen, G. B.; Salgado-Labouriau, M. L.; Schasignbitz, F.; Schreve-Brinkman, E. J.; Wille, M.

    2009-01-01

    The biomisation method is used to reconstruct Latin American vegetation at 6000±500 and 18 000±1000 radiocarbon years before present (14C yr BP) from pollen data. Tests using modern pollen data from 381 samples derived from 287 locations broadly reproduce potential natural vegetation. The strong temperature gradient associated with the Andes is recorded by a transition from high altitude cool grass/shrubland and cool mixed forest to mid-altitude cool temperate rain forest, to tropical dry, seasonal and rain forest at low altitudes. Reconstructed biomes from a number of sites do not match the potential vegetation due to local factors such as human impact, methodological artefacts and mechanisms of pollen representivity of the parent vegetation. At 6000±500 14C yr BP 255 samples are analysed from 127 sites. Differences between the modern and the 6000±500 14C yr BP reconstruction are comparatively small. Patterns of change relative to the modern reconstruction are mainly to biomes characteristic of drier climate in the north of the region with a slight more mesic shift in the south. Cool temperate rain forest remains dominant in western South America. In northwestern South America a number of sites record transitions from tropical seasonal forest to tropical dry forest and tropical rain forest to tropical seasonal forest. Sites in Central America also show a change in biome assignment to more mesic vegetation, indicative of greater plant available moisture, e.g. on the Yucat??n peninsula sites record warm evergreen forest, replacing tropical dry forest and warm mixed forest presently recorded. At 18 000±1000 14C yr BP 61 samples from 34 sites record vegetation that reflects a generally cool and dry environment. Cool grass/shrubland prevalent in southeast Brazil, Amazonian sites record tropical dry forest, warm temperate rain forest and tropical seasonal forest. Southernmost South America is dominated by cool grass/shrubland, a single site retains cool temperate

  19. Dynamic vegetation modeling of tropical biomes during Heinrich events

    Science.gov (United States)

    Handiani, Dian Noor; Paul, André; Dupont, Lydie M.

    2010-05-01

    Heinrich events are thought to be associated with a slowdown of the Atlantic Meridional Overturning Circulation (AMOC), which in turn would lead to a cooling of the North Atlantic Ocean and a warming of the South Atlantic Ocean (the "bipolar seesaw" hypothesis). The accompanying abrupt climate changes occurred not only in the ocean but also on the continents. Changes were strongest in the Northern Hemisphere but were registered in the tropics as well. Pollen data from Angola and Brazil showed that climate changes during Heinrich events affected vegetation patterns very differently in eastern South America and western Africa. To understand the differential response in the terrestrial tropics, we studied the vegetation changes during Heinrich events by using a dynamic global vegetation model (TRIFFID) as part of the University of Victoria (UVic) Earth System-Climate Model (ESCM). The model results show a bipolar seesaw pattern in temperature and precipitation during a near-collapse of the AMOC. The succession in plant-functional types (PFTs) showed changes from forest to shrubs to desert, including spreading desert in northwest Africa, retreating broadleaf trees in West Africa and northern South America, but advancing broadleaf trees in Brazil. The pattern is explained by a southward shift of the tropical rainbelt resulting in a strong decrease in precipitation over northwest and West Africa as well as in northern South America, but an increase in precipitation in eastern Brazil. To facilitate the comparison between modeled vegetation results with pollen data, we diagnosed the distribution of biomes from the PFT coverage and the simulated model climate. The biome distribution was computed for Heinrich event 1 and the Last Glacial Maximum as well as for pre-industrial conditions. We used a classification of biomes in terms of "mega-biomes", which were defined following a scheme originally proposed by BIOME 6000 (v 4.2). The biome distribution of the Sahel region

  20. On coupling global biome models with climate models

    OpenAIRE

    Claussen, M.

    1994-01-01

    The BIOME model of Prentice et al. (1992; J. Biogeogr. 19: 117-134), which predicts global vegetation patterns in equilibrium with climate, was coupled with the ECHAM climate model of the Max-Planck-Institut fiir Meteorologie, Hamburg, Germany. It was found that incorporation of the BIOME model into ECHAM, regardless at which frequency, does not enhance the simulated climate variability, expressed in terms of differences between global vegetation patterns. Strongest changes are seen only betw...

  1. Diverging responses of tropical Andean biomes under future climate conditions.

    Directory of Open Access Journals (Sweden)

    Carolina Tovar

    Full Text Available Observations and projections for mountain regions show a strong tendency towards upslope displacement of their biomes under future climate conditions. Because of their climatic and topographic heterogeneity, a more complex response is expected for biodiversity hotspots such as tropical mountain regions. This study analyzes potential changes in the distribution of biomes in the Tropical Andes and identifies target areas for conservation. Biome distribution models were developed using logistic regressions. These models were then coupled to an ensemble of 8 global climate models to project future distribution of the Andean biomes and their uncertainties. We analysed projected changes in extent and elevational range and identified regions most prone to change. Our results show a heterogeneous response to climate change. Although the wetter biomes exhibit an upslope displacement of both the upper and the lower boundaries as expected, most dry biomes tend to show downslope expansion. Despite important losses being projected for several biomes, projections suggest that between 74.8% and 83.1% of the current total Tropical Andes will remain stable, depending on the emission scenario and time horizon. Between 3.3% and 7.6% of the study area is projected to change, mostly towards an increase in vertical structure. For the remaining area (13.1%-17.4%, there is no agreement between model projections. These results challenge the common believe that climate change will lead to an upslope displacement of biome boundaries in mountain regions. Instead, our models project diverging responses, including downslope expansion and large areas projected to remain stable. Lastly, a significant part of the area expected to change is already affected by land use changes, which has important implications for management. This, and the inclusion of a comprehensive uncertainty analysis, will help to inform conservation strategies in the Tropical Andes, and to guide similar

  2. Generality of leaf trait relationships: A test across six biomes

    Energy Technology Data Exchange (ETDEWEB)

    Reich, P.B. [Univ. of Minnesota, Saint Paul, MN (United States). Dept. of Forest Resources; Ellsworth, D.S. [Brookhaven National Lab., Upton, NY (United States). Dept. of Applied Science; Walters, M.B. [Michigan State Univ., East Lansing, MI (United States). Dept. of Forestry; Vose, J.M. [Forest Service, Otto, NC (United States). Coweeta Hydrological Lab.; Gresham, C. [Clemson Univ., Georgetown, SC (United States). Baruch Forest Inst.; Volin, J.C. [Florida Atlantic Univ., Davie, FL (United States). Div. of Science; Bowman, W.D. [Inst. of Arctic and Alpine Research, Boulder, CO (United States). Mountain Research Station]|[Univ. of Colorado, Boulder, CO (United States). Dept. of Evolutionary, Population, and Organismic Biology

    1999-09-01

    Convergence in interspecific leaf trait relationships across diverse taxonomic groups and biomes would have important evolutionary and ecological implications. Such convergence has been hypothesized to result from trade-offs that limit the combination of plant traits for any species. Here the authors address this issue by testing for biome differences in the slope and intercept of interspecific relationships among leaf traits: longevity, net photosynthetic capacity (A{sub max}), leaf diffusive conductance (G{sub S}), specific leaf area (SLA), and nitrogen (N) status, for more than 100 species in six distinct biomes of the Americas. The six biomes were: alpine tundra-subalpine forest ecotone, cold temperate forest-prairie ecotone, montane cool temperate forest, desert shrubland, subtropical forest, and tropical rain forest. Despite large differences in climate and evolutionary history, in all biomes mass-based leaf N (N{sub mass}), SLA, G{sub S}, and A{sub max} were positively related to one another and decreased with increasing leaf life span. The relationships between pairs of leaf traits exhibited similar slopes among biomes, suggesting a predictable set of scaling relationships among key leaf morphological, chemical, and metabolic traits that are replicated globally among terrestrial ecosystems regardless of biome or vegetation type. However, the intercept (i.e., the overall elevation of regression lines) of relationships between pairs of leaf traits usually differed among biomes. With increasing aridity across sites, species had greater A{sub max} for a given level of G{sub S} and lower SLA for any given leaf life span. Using principal components analysis, most variation among species was explained by an axis related to mass-based leaf traits (A{sub max}, N, and SLA) while a second axis reflected climate, G{sub S}, and other area-based leaf traits.

  3. Transferability of results of cost utility analyses for biologicals in inflammatory conditions for Central and Eastern European countries.

    Science.gov (United States)

    Gulácsi, László; Rencz, Fanni; Péntek, Márta; Brodszky, Valentin; Lopert, Ruth; Hevér, Noémi V; Baji, Petra

    2014-05-01

    Several Central and Eastern European (CEE) countries require cost-utility analyses (CUAs) to support reimbursement formulary listing. However, CUAs informed by local evidence are often unavailable, and the cost-effectiveness of the several currently reimbursed biologicals is unclear. To estimate the cost-effectiveness as multiples of per capita GDP/quality adjusted life years (QALY) of four biologicals (infliximab, etanercept, adalimumab, golimumab) currently reimbursed in six CEE countries in six inflammatory rheumatoid and bowel disease conditions. Systematic literature review of published cost-utility analyses in the selected conditions, using the United Kingdom (UK) as reference country and with study selection criteria set to optimize the transfer of results to the CEEs. Prices in each CEE country were pro-rated against UK prices using purchasing power parity (PPP)-adjusted per capita GDP, and local GDP per capita/QALY ratios estimated. Central and Eastern European countries list prices were 144-333% higher than pro rata prices. Out of 85 CUAs identified by previous systematic literature reviews, 15 were selected as a convenience sample for estimating the cost-effectiveness of biologicals in the CEE countries in terms of per capita GDP/QALY. Per capita GDP/QALY values varied from 0.42 to 6.4 across countries and conditions (Bulgaria: 0.97-6.38; Czech Republic: 0.42-2.76; Hungary: 0.54-3.54; Poland: 0.59-3.90; Romania: 0.77-5.07; Slovakia: 0.55-3.61). While results must be interpreted with caution, calculating pro rata (cost-effective) prices and per capita GDP/QALY ratios based on CUAs can aid reimbursement decision-making in the absence of analyses using local data.

  4. Human Development VII: A Spiral Fractal Model of Fine Structure of Physical Energy Could Explain Central Aspects of Biological Information, Biological Organization and Biological Creativity

    Directory of Open Access Journals (Sweden)

    Søren Ventegodt

    2006-01-01

    Full Text Available In this paper we have made a draft of a physical fractal essence of the universe, a sketch of a new cosmology, which we believe to lay at the root of our new holistic biological paradigm. We present the fractal roomy spiraled structures and the energy-rich dancing “infinite strings” or lines of the universe that our hypothesis is based upon. The geometric language of this cosmology is symbolic and both pre-mathematical and pre-philosophical. The symbols are both text and figures, and using these we step by step explain the new model that at least to some extent is able to explain the complex informational system behind morphogenesis, ontogenesis, regeneration and healing. We suggest that it is from this highly dynamic spiraled structure that organization of cells, organs, and the wholeness of the human being including consciousness emerge. The model of ““dancing fractal spirals” carries many similarities to premodern cultures descriptions of the energy of the life and universe. Examples are the Native American shamanistic descriptions of their perception of energy and the old Indian Yogis descriptions of the life-energy within the body and outside. Similar ideas of energy and matter are found in the modern superstring theories. The model of the informational system of the organism gives new meaning to Bateson’s definition of information: “A difference that makes a difference”, and indicates how information-directed self-organization can exist on high structural levels in living organisms, giving birth to their subjectivity and consciousness.

  5. Biologic restoration of a traumatized maxillary central incisor in a toddler: a case report.

    Science.gov (United States)

    John, Sheen Ann; Anandaraj, S; George, Sageena

    2014-01-01

    Trauma to the anterior teeth is relatively common in young children and teenagers. Traumatized anterior teeth require quick functional and aesthetic repair, and poses a challenge to the dental practitioner owing to the lack of co-operation ceded and the longer time invested. Reattachment of tooth fragment should be the first choice to restoring teeth when a usable fragment is available, since it gives a psychological and aesthetic advantage over the conventional technique. With the vast improvement in adhesive technology, reattachment is definitely a predictable treatment option for very young children. This paper describes the treatment of a 2½ year old female child who sustained crown-root fracture, extending subgingivally, in primary upper central incisor.

  6. Reproductive biology knowledge, and behaviour of teenagers in East, Central and Southern Africa: the Zimbabwe case study.

    Science.gov (United States)

    Mbizvo, M T; Kasule, J; Gupta, V; Rusakaniko, S; Gumbo, J; Kinoti, S N; Mpanju-Shumbusho, W; Sebina-Zziwa; Mwateba, R; Padayachy, J

    1995-11-01

    Sexuality in the teenager is often complicated by unplanned/unwanted pregnancy, abortion and the risks of STDs including AIDS. There is therefore a need for improved understanding of factors affecting adolescent sexuality and the implementation of programmes designed to improve their knowledge, risk awareness and subsequent behavioural outcomes. A multicentre study of reproductive health knowledge and behaviour followed by a health education intervention was undertaken amongst teenagers in selected countries of East, Central and Southern Africa. Reported here are findings at baseline derived from the Zimbabwe component on reproductive biology knowledge and behavior. A self-administered questionnaire was used among 1 689 adolescent pupils drawn from rural, urban, co-education, single sex, boarding and day secondary schools in Zimbabwe. Correct knowledge on reproductive biology as measured by the meaning and interpretation of menstruation and wet dreams varied by school from 68 pc to 86 pc, with a significant trend (p < 0,01) based on level of education at baseline. The reported mean age at which menarche took place was 13,5 years +/- 1,3 (mean +/- SD). First coitus was reported to have taken place at the mean age of 12 years for boys and 13,6 years for girls. Seventeen pc of the adolescent pupils reported that they were sexually experienced and 33,2 had relationships. There were misconceptions reported on menstruation with 23 pc reporting that it was an illness. Peers, followed by magazines were the first sources of information on various aspects of reproductive biology, both of which might not provide the correct first information. Among pupils reporting that they were sexually experienced, the largest proportion (56 pc) had unprotected sex. The findings point to the need for targeting the adolescent pupils for information on reproductive biology and increased awareness on the risks of pregnancy, STDs and HIV.

  7. A remarkable finding that suggests the existence of a new groundwater biome based on chemoautotrophic resources, named

    Directory of Open Access Journals (Sweden)

    Ştefan Negrea

    2009-01-01

    Full Text Available An important work of subterranean biology, signed by Francis Dov Por, Ophel: a groundwater biome based on chemoautotrophic resources. The global significance of the Ayyalon cave finds, Israel is presented and discussed in the present paper. The subject is a remarkable discovery suggesting the existence of a new aquatic subterranean biome autonomous energy based the author calls Ophel, the Hebrew word for “darkness” and “netherworld”. For F.D. Por, this biome links different marine chemosynthetic ecosystems in a global biospheric entity. Finally, F.D. POR hypothesizes on the existence of three overlapped biospheres: the bacteriosphere in the depths of the planet’s crust, which does not require light or oxygen; the aphotic, subterranean deuterobiosphere, formed of bacterial chemosynthesis based eukaryotes and limited-supplied dissolved oxygen from above-ground; the above-ground eubiosphere, based on aerobic photosynthesis. I would like to emphasize that, at my suggestion, Prof. Dr. F.D. Por participated at the 18th International Symposium of Biospeleology from Cluj-Napoca (Romania at 10th to 15th July 2006 where he mentioned for the first time orally some data on the Ayyalon Cave and the Ophel biome.

  8. The biology of Aedes (Ochlerotatus albifasciatus Macquart, 1838 (Diptera: Culicidae in Central Argentina

    Directory of Open Access Journals (Sweden)

    Francisco F. Ludueña Almeida

    1995-08-01

    Full Text Available Aedes albifasciatus is a flood water mosquito ocurring in the southern countries of South America. It is a competent vector of the Western Equine Encephalitis (WEE and causes important losses on milk and beef production in central Argentina. Field work was carried out from December 1990 to March 1993, on a monthly basis during the dry season and biweekly during the rainy season. Larvae were collected using the 'dipping' technique and females with CDC traps baited with CO2. Field collected larvae were used to build laboratory cohorts, from which basic population parameters were estimated. Eggs survived up to six months on dry soil, although there was a linear decrease of viability with time. At 23ºC, larval development time was around nine days, and all adults emerged within one week. The estimation of larval development in the laboratory seems to be very near the development on the field, as larvae have been collected on average eight days after a rainfall. Egg to adult survival was 83%, with the highest mortality on fourth larval instar (6%. In the laboratory studies, sex proportion among the adults was 1:1, females lived longer than males (median 13 and five days, respectively, and adult survival pattern showed a constant number of individuals dying per unit time. Field collected females layed an average of 84 eggs per batch, and completing up to five gonotrophic cycles, suggesting an estimated survival of up to 35-50 days.

  9. Assessment of DDT levels in selected environmental media and biological samples from Mexico and Central America.

    Science.gov (United States)

    Pérez-Maldonado, Iván N; Trejo, Antonio; Ruepert, Clemens; Jovel, Reyna del Carmen; Méndez, Mónica Patricia; Ferrari, Mirtha; Saballos-Sobalvarro, Emilio; Alexander, Carlos; Yáñez-Estrada, Leticia; Lopez, Dania; Henao, Samuel; Pinto, Emilio R; Díaz-Barriga, Fernando

    2010-03-01

    Taking into account the environmental persistence and the toxicity of DDT, the Pan American Health Organization (PAHO) organized a surveillance program in Mesoamerica which included the detection of residual DDT in environmental (soil) and biological samples (fish tissue and children's blood). This program was carried out in communities from Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. This paper presents the first report of that program. As expected, the results show that the levels for [summation operator] DDT in soil (outdoor or indoor) and fish samples in the majority of the locations studied are below guidelines. However, in some locations, we found children with high concentrations of DDT as in Mexico (mean level 50.2 ng/mL). Furthermore, in some communities and for some matrices, the DDT/DDE quotient is higher than one and this may reflect a recent DDT exposure. Therefore, more efforts are needed to avoid exposure and to prevent the reintroduction of DDT into the region. In this regard it is important to know that under the surveillance of PAHO and with the support of UNEP, a regional program in Mesoamerica for the collection and disposal of DDT and other POPs stockpiles is in progress. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  10. Biology of Crassicutis cichlasomae, a parasite of cichlid fishes in Mexico and Central America.

    Science.gov (United States)

    Scholz, T; Pech-Ek, M C; Rodriguez-Canul, R

    1995-03-01

    Field study on the biology of Crassicutis cichlasomae Manter, 1936 (Digenea: Homalometridae) was carried out in a small swamp in a limestone factory near Mérida, Yucatán, Mexico. Aquatic snails, Littorina (Littoridinopis) angulifera, harbouring C. cichlasomae rediae, cercariae and metacercariae, served both as the first and second intermediate hosts. Feeding experiments confirmed the conspecificity of metacercariae from naturally infected snails with adults from naturally infected fish. Gravid C. cichlasomae worms were obtained from experimentally infected fish 19 days post exposure at 22-24 degrees C. Examination of fish from the swamp in Mitza and other localities in the Yucatan Peninsula showed that the cichlids Cichlasoma urophthalmus and C. meeki were definitive hosts of C. cichlasomae. There was no pronounced preference of C. cichlasomae adults for the site of their location in the intestine of the definitive host; a slightly higher proportion (41%) of worms was only found in the anterior third of the gut. The time of miracidium development varied from 18.5 to 27.5 days; different temperature (20.1-35.7 degrees C) or light/darkness regimes influenced only slightly the rate of embryonic development, with shorter development times at higher temperature (34.8-35.7 degrees C) and constant darkness and/or light. With the exception of the sporocyst, all developmental stages are described and figured.

  11. INSECT AS BIOLOGICAL INDICATOR FROM PROTECTED TO THE DISTURB LANDSCAPE IN CENTRAL JAVA INDONESIA

    Directory of Open Access Journals (Sweden)

    Karuniawan Puji Wicaksono

    2011-02-01

    Full Text Available In the biological science, invertebrate (especially insect diversity is relatively well known. Yet, little study about their interaction with specific land use or specific system function. With the rapid changes of landscape, biodiversity is also changes in response to human impact; due to each organism have the specific interaction with certain environment. In this research, the assessment of insect order in the different landscape types was conducted using several method of trapping to understand the specific pattern of insect which are inhabited the landscape. The objectives of this research were monitored the Insect diversity, its ecological importance to agro-forestry ecosystem, and compare it with other forest type in this area. Another objective was determined the insect characteristic as the indicator of environmental quality on each land-use system (forest, agro-forestry, plantation and monoculture. Monoculture agriculture has the largest number of Lepidoptera and Hemiptera order (herbivore insect dominated while in agro-forest system has the largest number of Diptera and coleoptera order. Protected forest, plantation forest and agro-forestry showed the similar index number which shows the similar ecological services for the insect as their habitat. However, in the monoculture agriculture, there was an unbalance insect composition and high dominance.

  12. A Brief History of the Study of Fish Osmoregulation: The Central Role of the Mt. Desert Island Biological Laboratory

    Science.gov (United States)

    Evans, David H.

    2010-01-01

    The Mt. Desert Island Biological Laboratory (MDIBL) has played a central role in the study of fish osmoregulation for the past 80 years. In particular, scientists at the MDIBL have made significant discoveries in the basic pattern of fish osmoregulation, the function of aglomerular kidneys and proximal tubular secretion, the roles of NaCl cotransporters in intestinal uptake and gill and rectal gland secretion, the role of the shark rectal gland in osmoregulation, the mechanisms of salt secretion by the teleost fish gill epithelium, and the evolution of the ionic uptake mechanisms in fish gills. This short review presents the history of these discoveries and their relationships to the study of epithelial transport in general. PMID:21423356

  13. Central Giant Cell Granuloma of the Jaws: Correlation between Vascularity and Biologic Behavior

    Directory of Open Access Journals (Sweden)

    Saede Atarbashi Moghadam

    2017-03-01

    Full Text Available Introduction: Giant cell lesions of the bone comprise a group of jaw bone pathologies. Different pathogeneses such as reactive, vascular or neoplastic have been proposed for these lesions. In addition, differentiating between aggressive and nonaggressive central giant cell granuloma (CGCG of the jaws based on histopathologic features is still impossible and due to different treatment protocols for the two groups, correct diagnosis is necessary. The purpose of this study was to compare the expression of CD34 between aggressive and nonaggressive CGCGs of the jaws. Methods & Materials: This retrospective study was carried out on 16 paraffin blocks in each aggressive and nonaggressive CGCGs group. The expression of CD34 was evaluated with immunohistochemical technique. Afterwards, t-test was used for quantitative evaluation and comparison of CD34 expression among the two groups. Eventually, statistical analysis was performed using Spss20 software. Significance was assigned at p < 0.05. Results: In the present study, the average age of patients in aggressive and nonaggressive groups was 20.93±8.08 and 26.18±16.97, respectively. In both groups, female predilection was observed. Mandible was the most common site of involvement in the aggressive group and the distribution of nonaggressive lesions was equal between both jaws. Although the expression of CD34 in the aggressive group was higher than the nonaggressive group, no statistically significant difference was seen (p=0.15. Conclusion: According to the results of the current study, it appears that CD34 protein cannot be used for identifying the clinical behavior of CGCGs.

  14. Physical and biological characteristics of the winter-summer transition in the Central Red Sea

    KAUST Repository

    Zarokanellos, Nikolaos

    2017-07-25

    The Central Red Sea (CRS) lies between two distinct hydrographic and atmospheric regimes. In the southern Red Sea, seasonal monsoon reversal regulates the exchange of water between the Red Sea and the Indian Ocean. In the northern Red Sea, intermediate and occasionally deep water are formed during winter to sustain the basin\\'s overturning circulation. Highly variable mesoscale eddies and the northward flowing eastern boundary current (EBC) determine the physical and biogeochemical characteristics of the CRS. Ship-based and glider observations in the CRS between March and June 2013 capture key features of the transition from winter to summer and depict the impact of the eddy activity on the EBC flow. Less saline and relatively warmer water of Indian Ocean origin reaches the CRS via the EBC. Initially, an anticyclonic eddy with diameter of 140 km penetrating to 150m depth with maximum velocities up to 30–35 cm s prevails in the CRS. This anticyclonic eddy appears to block or at least redirect the northward flow of the EBC. Dissipation of the eddy permits the near-coastal, northward flow of the EBC and gives place to a smaller cyclonic eddy with a diameter of about 50 km penetrating to 200 m depth. By the end of May, as the northerly winds become stronger and persistent throughout the basin, characteristic of the summer southwest monsoon wind regime, the EBC, and its associated lower salinity water became less evident, replaced by the saltier surface water that characterizes the onset of the summer stratification in the CRS.

  15. Floral biology of Senecio macrophyllus M. BIEB. (Asteraceae, a rare Central European steppe plant

    Directory of Open Access Journals (Sweden)

    Bożenna Czarnecka

    2014-03-01

    Full Text Available Knowledge of the flowering phase and plant pollination ecology is very important for understanding the life history of long-lived perennials. In the case of rare species, the information may have implications for conservation practices. Our studies on flower morphology and blooming biology of the vulnerable plant Senecio macrophyllus M. BIEB. were conducted in situ (flowering, activity of insect visitors in the largest population in SE Poland and in laboratory (light and scanning electron microscopy. The disc florets open diurnally with most intensive anthesis in the early afternoon and attract insect visitors with nectar and pollen. In highly protandrous disc florets, pollen viability decreases in time, whereas stigma receptivity increases. The upper part of the pistil forms a brush-like pollen presenter, covered with unicellular trichomes with chromoplasts. Pollen presentation lasts 4–11 hours per floret, and 8 days in a single head, the main function of which is to extend the availability of male gamets for reproduction. The number of florets per head, the head size, and the number of pollen grains produced per anther, and the pollen grain viability differed significantly between microsites. The finding indicates that, apart from the biotic factors, abiotic conditions may considerably influence generative reproduction of the species. In the study area, the principal visitors of S. macrophyllus flowers were Hymenoptera, with predominance of Apis mellifera (53.4% of visits. The remarkable share of butterflies (13.9% recognized as the long-distance moving insects may improve the genetic variability of individuals within a fragmented population. A more detailed study is necessary to explain the role of insect visitors in effective pollination and in gene transfer between patches. The assessment of optimal conditions for the generative reproduction is fundamental for the in situ conservation of this rare species.

  16. Biogeochemical cycling in terrestrial ecosystems of the Caatinga Biome.

    Science.gov (United States)

    Menezes, R S C; Sampaio, E V S B; Giongo, V; Pérez-Marin, A M

    2012-08-01

    The biogeochemical cycles of C, N, P and water, the impacts of land use in the stocks and flows of these elements and how they can affect the structure and functioning of Caatinga were reviewed. About half of this biome is still covered by native secondary vegetation. Soils are deficient in nutrients, especially N and P. Average concentrations of total soil P and C in the top layer (0-20 cm) are 196 mg kg(-1) and 9.3 g kg(-1), corresponding to C stocks around 23 Mg ha(-1). Aboveground biomass of native vegetation varies from 30 to 50 Mg ha(-1), and average root biomass from 3 to 12 Mg ha(-1). Average annual productivities and biomass accumulation in different land use systems vary from 1 to 7 Mg ha(-1) year(-1). Biological atmospheric N2 fixation is estimated to vary from 3 to 11 kg N ha(-1) year-1 and 21 to 26 kg N ha(-1) year(-1) in mature and secondary Caatinga, respectively. The main processes responsible for nutrient and water losses are fire, soil erosion, runoff and harvest of crops and animal products. Projected climate changes in the future point to higher temperatures and rainfall decreases. In face of the high intrinsic variability, actions to increase sustainability should improve resilience and stability of the ecosystems. Land use systems based on perennial species, as opposed to annual species, may be more stable and resilient, thus more adequate to face future potential increases in climate variability. Long-term studies to investigate the potential of the native biodiversity or adapted exotic species to design sustainable land use systems should be encouraged.

  17. Dew formation on the surface of biological soil crusts in central European sand ecosystems

    Directory of Open Access Journals (Sweden)

    T. Fischer

    2012-11-01

    Full Text Available Dew formation was investigated in three developmental stages of biological soil crusts (BSC, which were collected along a catena of an inland dune and in the initial substrate. The Penman equation, which was developed for saturated surfaces, was modified for unsaturated surfaces and used for prediction of dewfall rates. The levels of surface saturation required for this approach were predicted using the water retention functions and the thicknesses of the BSCs. During a first field campaign (2–3 August 2011, dewfall increased from 0.042 kg m−2 for the initial sandy substrate to 0.058, 0.143 and 0.178 kg m−2 for crusts 1 to 3, respectively. During a second field campaign (17–18 August 2011, where dew formation was recorded in 1.5 to 2.75-h intervals after installation at 21:30 CEST, dewfall increased from 0.011 kg m−2 for the initial sandy substrate to 0.013, 0.028 and 0.055 kg m−2 for crusts 1 to 3, respectively. Dewfall rates remained on low levels for the substrate and for crust 1, and decreased overnight for crusts 2 and 3 (with crust 3 > crust 2 > crust 1 throughout the campaign. Dew formation was well reflected by the model response. The suggested mechanism of dew formation involves a delay in water saturation in near-surface soil pores and extracellular polymeric substances (EPS where the crusts were thicker and where the water capacity was high, resulting in elevated vapor flux towards the surface. The results also indicate that the amount of dewfall was too low to saturate the BSCs and to observe water flow into deeper soil. Analysis of the soil water retention curves revealed that, despite the sandy mineral matrix, moist crusts clogged by swollen EPS pores exhibited a clay-like behavior. It is hypothesized that BSCs gain double benefit from suppressing their competitors by runoff generation and from improving their water supply by dew collection. Despite higher amounts of dew, the

  18. Biological aspects of Leucothyreus alvarengai Frey and Leucothyreus aff. semipruinosus Ohaus (Coleoptera, Melolonthidae, Rutelinae in crop succession at central Brazil

    Directory of Open Access Journals (Sweden)

    Alex Furquim Pereira

    2013-09-01

    Full Text Available Biological aspects of Leucothyreus alvarengai Frey and Leucothyreus aff. semipruinosus Ohaus (Coleoptera, Melolonthidae, Rutelinae in crop succession at central Brazil. Beetles of the family Melolonthidae make up a large group and some species are considered pests of planted crops. Little information is available on the basic biological aspects of the genus Leucothyreus, such as association with cultivated crops and their occurrence periods. Therefore studies were developed in soybean and corn crops in Tangará da Serra, Mato Grosso, Brazil, with the objective of studying the occurrence and biological aspects of Leucothyreus alvarengai Frey and Leucothyreus aff. semipruinosus Ohaus. For acquisition of immature specimens of both species, in April 2011 sampling was performed in corn fields, in July and October in the fallow area, and in soybeans fields planted in December; in 2012 sampling was performed in January and February in soybean fields and in March in corn fields. In 2011 the total number of larvae obtained in April, July, October and December were 100, 6, 30 and 27, and in January, February and March of 2012 these quantities were 32, 52 and 65 larvae, respectively. In all sampling events the larvae of L. alvarengai were collected in greater quantity. At the beginning of the reproductive period of L. alvarengai and L. aff. semipruinosus, it was observed that the adults began to fly and soon after started oviposition in the field in September. The appearance of larvae coincides with the time of soybean planting in the field, thus the larvae feed on roots of soybean plants at the beginning of their development and the cycle from egg to adult of the two species was completed in one year.

  19. Modelling insights on the partition of evapotranspiration components across biomes

    Science.gov (United States)

    Fatichi, Simone; Pappas, Christoforos

    2017-04-01

    Recent studies using various methodologies have found a large variability (from 35 to 90%) in the ratio of transpiration to total evapotranspiration (denoted as T:ET) across biomes or even at the global scale. Concurrently, previous results suggest that T:ET is independent of mean precipitation and has a positive correlation with Leaf Area Index (LAI). We used the mechanistic ecohydrological model, T&C, with a refined process-based description of soil resistance and a detailed treatment of canopy biophysics and ecophysiology, to investigate T:ET across multiple biomes. Contrary to observation-based estimates, simulation results highlight a well-constrained range of mean T:ET across biomes that is also robust to perturbations of the most sensitive parameters. Simulated T:ET was confirmed to be independent of average precipitation, while it was found to be uncorrelated with LAI across biomes. Higher values of LAI increase evaporation from interception but suppress ground evaporation with the two effects largely cancelling each other in many sites. These results offer mechanistic, model-based, evidence to the ongoing research about the range of T:ET and the factors affecting its magnitude across biomes.

  20. Conserving the Brazilian semiarid (Caatinga) biome under climate change

    DEFF Research Database (Denmark)

    Oliveira, Guilherme de; Bastos Araujo, Miguel; Rangel, Thiago Fernado

    2012-01-01

    to assess changes in climate suitability across individual species ranges, ensemble forecasting was used based on seven bioclimatic envelope models, three atmosphere–ocean general circulation models, and two greenhouse emission gas scenarios for 2020, 2050, and 2080. We found that most species will gain...... additional threats to the biome’s biodiversity. Here, we ask if the remnants of natural vegetation in Caatinga biome, where endemic terrestrial vertebrate species occur, are likely to retain more climatic suitability under climate change scenarios than other less pristine areas of the biome. In order......The Caatinga is a semiarid biome of the northeast of Brazil with only 1 % of its territory currently conserved. The biome’s biodiversity is highly threatened due to exposure to land conversion for agricultural and cattle ranch. Climate forecasts predict increases in aridity, which could pose...

  1. Remotely sensed phenology for mapping biomes and vegetation functional types

    CSIR Research Space (South Africa)

    Wessels, Konrad J

    2009-07-01

    Full Text Available clearly captured in Fig. 3. The majority of the pixels in the Savanna have a start of growing season in late October, midposition in February and end in June (Fig. 3). In contrast, the winter rainfall Succulent Karoo have a start of growing season... initially split the biomes based on vegetation production and then by the seasonality of growth IV - 1035 (Fig. 4). The three arid biomes (Desert, Succulent and Nama Figure 3. Frequency histograms of the mean START, midposition (MID) and END date...

  2. La prosodia como identificador biométrico

    OpenAIRE

    Farrús i Cabeceran, Mireia

    2011-01-01

    La biometría tiene como objetivo el reconocimiento de personas mediante uno o más identificadores biométricos como la voz, la cara o las huellas dactilares, entre otros. Gracias a la buena aceptación social y el poco intrusismo en los individuos, la voz ha sido, tradicionalmente, uno de los identificadores más utilizados en los sistemas biométricos. Estos sistemas de reconocimiento basados en la voz utilizan, habitualmente, características relacionadas con el espectro de la voz. No obstante, ...

  3. Population dynamics and reproductive biology of Barilius bendelisis (Cyprinidae: Cypriniformes) from river Gaula of Central Indian Himalaya.

    Science.gov (United States)

    Saxena, Neha; Patiyal, Rabindar Singh; Dube, Kiran; Tiwari, Virendra K

    2016-09-01

    The Indian hill trout cyprinid, Barilius bendelisis is a member of family Cyprinidae that dwells in shallow, cold, and clear water. In this study, growth parameters and reproductive biology of Indian hill trout, Barilius bendelisis from river Gaula, Central Himalaya region, India, were studied. The length-frequency data were grouped sex wise and were analyzed to determine the growth and mortality parameters using the computer software programme, FAO-ICLARM Stock Assessment Tool (FISAT II). Altogether, 501 individuals were collected from river Gaula (November 2013-October 2014) and were preserved in formalin for further analysis. The results showed that the female outnumbered the male population. The minimum GSI of females was observed in the month of October (4.93 ± 0.26) and for males in the month of June and July (0.093 ± 0.12), whereas, the maximum value was in the month of April for both females (13.47 ± 0.52) and males (1.21 ± 0.12). Fluctuation in GSI values had a bimodal pattern showing two peaks during March-May and August-September in both the sexes, indicating the common spawning period of fish. The slope of regression showed the negative allometric growth for both males and females (b= 2.65 for male and b= 2.5 for female). A significant relationship between length and weight was observed in the present study (p < 0.05). The ELEFAN-I estimated L∞ and K of the von Bertalanffy growth factor for males (17.33 cm and 0.310 per year), females (17.33 cm and 0.3 per year) and pooled sexes (17.33 cm and 0.240 per year). The results indicated that Barilius bendelisis is a small sized fish having negative allometric growth that spawns twice a year. Thus, the present study on biological traits represents the baseline information for effective production, conservation and restoration planning.

  4. Variation in decomposition rates in the fynbos biome, South Africa: the role of plant species and plant stoichiometry.

    Science.gov (United States)

    Bengtsson, Jan; Janion, Charlene; Chown, Steven L; Leinaas, Hans Petter

    2011-01-01

    Previous studies in the fynbos biome of the Western Cape, South Africa, have suggested that biological decomposition rates in the fynbos vegetation type, on poor soils, may be so low that fire is the main factor contributing to litter breakdown and nutrient release. However, the fynbos biome also comprises vegetation types on more fertile soils, such as the renosterveld. The latter is defined by the shrub Elytropappus rhinocerotis, while the shrub Galenia africana may become dominant in overgrazed areas. We examined decomposition of litter of these two species and the geophyte Watsonia borbonica in patches of renosterveld in an agricultural landscape. In particular, we sought to understand how plant species identity affects litter decomposition rates, especially through variation in litter stoichiometry. Decomposition (organic matter mass loss) varied greatly among the species, and was related to litter N and P content. G. africana, with highest nutrient content, lost 65% of its original mass after 180 days, while E. rhinocerotis had lost ca. 30%, and the very nutrient poor W. borbonica biome. Thus, biological decomposition has likely been underestimated and, along with small-scale variation in ecosystem processes, would repay further study.

  5. SulfoSYS (Sulfolobus Systems Biology): towards a silicon cell model for the central carbohydrate metabolism of the archaeon Sulfolobus solfataricus under temperature variation

    NARCIS (Netherlands)

    Albers, S.V.; Birkeland, N.K.; Driessen, A.J.M.; Gertig, S.; Haferkamp, P.; Klenk, H.P.; Kouril, T.; Manica, A.; Pham, T.K.; Ruoff, P.; Schleper, C.; Schomburg, D.; Sharkey, K.; Siebers, B.; Sierocinski, P.; Steur, R.; Oost, van der J.; Westerhoff, H.V.; Wieloch, P.; Wright, P.C.; Zaparty, M.

    2009-01-01

    SulfoSYS (Sulfolobus Systems Biology) focuses on the study of the CCM (central carbohydrate metabolism) of Sulfolobus solfataricus and its regulation under temperature variation at the systems level. In Archaea, carbohydrates are metabolized by modifications of the classical pathways known from

  6. Sulfosys (Sulfolobus Systems Biology): towards a silicon cell model for the central carbohydrate metabolism of the archaeon Sulfolobus solfataricus under temperature variation.

    NARCIS (Netherlands)

    Albers, S.V.; Birkeland, N.K.; Driessen, A.J.; Gertig, S.; Haferkamp, P.; Klenk, H.P.; Kouril, T.; Manica, A.; Pham, T.K.; Ruoff, P.; Schleper, C.; Schomburg, D.; Sharkey, K.J.; Siebers, B.; Sierocinski, P.; Steuer, R.; van der Oost, J.; Westerhoff, H.V.; Wieloch, P.; Wright, P.C.; Zaparty, M.

    2009-01-01

    SulfoSYS (Sulfolobus Systems Biology) focuses on the study of the CCM (central carbohydrate metabolism) of Sulfolobus solfataricus and its regulation under temperature variation at the systems level. In Archaea, carbohydrates are metabolized by modifications of the classical pathways known from

  7. SulfoSYS (Sulfolobus Systems Biology) : towards a silicon cell model for the central carbohydrate metabolism of the archaeon Sulfolobus solfataricus under temperature variation

    NARCIS (Netherlands)

    Albers, Sonja-Verena; Birkeland, Nils-Kare; Driessen, Arnold J. M.; Gertig, Susanne; Haferkamp, Patrick; Klenk, Hans-Peter; Kouril, Theresa; Manica, Andrea; Pham, Trong K.; Ruoff, Peter; Schleper, Christa; Schomburg, Dietmar; Sharkey, Kieran J.; Siebers, Bettina; Sierocinski, Pawel; Steuer, Ralf; van der Oost, John; Westerhoff, Hans V.; Wieloch, Patricia; Wright, Phillip C.; Zaparty, Melanie; Birkeland, Nils-Kåre

    SulfoSYS (Sulfolobus Systems Biology) focuses on the study of the CCM (central carbohydrate metabolism) of Sulfolobus solfataricus and its regulation under temperature variation at the systems level. in Archaea, carbohydrates are metabolized by modifications of the classical pathways known from

  8. Karoo biome: a preliminary sythesis. Part 1 - physical environment

    CSIR Research Space (South Africa)

    Cowling, RM

    1986-01-01

    Full Text Available . It is a multi-authored publication covering a wide range of topics. This first volume summarizes what is currently known on the physical environment of the biome; namely geology, soils, climate, hydrology, geohydrology and soil erosion. Other aspects...

  9. Importance of soil-water to the Caatinga biome, Brazil

    NARCIS (Netherlands)

    Alves Rodrigues Pinheiro, Everton; Metselaar, Klaas; Jong van Lier, de Quirijn; Araújo, de José Carlos

    2016-01-01

    Northeastern Brazil is hydrologically characterized by recurrent droughts leading to a highly vulnerable natural water resource system. The region contains the Caatinga biome, covering an area of approximately 800000km2. To increase insight in water balance components for this sparsely

  10. South African Red Data Book: Plants - fynbos and Karoo biomes

    CSIR Research Space (South Africa)

    Hall, AV

    1985-01-01

    Full Text Available In this report a list is given of 1 808 rare, threatened and recently extinct plants in the fynbos and karoo biomes in the Cape Province of South Africa. The area covers the south-western and southern Cape, Namaqualand and the Karoo. Following...

  11. Climate control of terrestrial carbon exchange across biomes and continents

    Science.gov (United States)

    Chuixiang Yi; Daniel Ricciuto; Runze Li; John Wolbeck; Xiyan Xu; Mats Nilsson; John Frank; William J. Massman

    2010-01-01

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate-carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO2 exchange with the atmosphere across biomes...

  12. Climate control of terrestrial carbon exchange across biomes and continents

    Czech Academy of Sciences Publication Activity Database

    Yi, C.; Ricciuto, D.; Marek, Michal V.

    2010-01-01

    Roč. 5, č. 3 (2010), s. 034007 ISSN 1748-9326 Institutional research plan: CEZ:AV0Z60870520 Keywords : NEE * climate control * terrestrial carbon sequestration * temperature * dryness * eddy flux * biomes * photosynthesis * respiration * global carbon cycle Subject RIV: EH - Ecology, Behaviour Impact factor: 3.049, year: 2010

  13. Anthropogenic biomes: a key contribution to earth-system science

    Science.gov (United States)

    Lilian Alessa; F. Stuart Chapin

    2008-01-01

    Human activities now dominate most of the ice-free terrestrial surface. A recent article presents a classification and global map of human-influenced biomes of the world that provides a novel and potentially appropriate framework for projecting changes in earth-system dynamics.

  14. The effect of heterogeneous landscape dynamics on ecotone types at two convergent semi-arid biomes

    Science.gov (United States)

    Landscapes in biome transition zones consist of a mosaic of patches dominated or codominated by species from adjacent biomes. Shifts in the vegetation composition and dynamics of a biome transition zone depend upon the underlying patch dynamics of the ecotones between these dominant species. Landsca...

  15. Importance of ecotone type to landscape dynamics at biome transition zones

    Science.gov (United States)

    Landscapes in biome transition zones consist of a mosaic of patches dominated or codominated by species from adjacent biomes. Shifts in the vegetation composition and dynamics of a biome transition zone depend upon the underlying patch dynamics of the ecotones between these dominant species. Landsc...

  16. Birth of a biome: insights into the assembly and maintenance of the Australian arid zone biota.

    Science.gov (United States)

    Byrne, M; Yeates, D K; Joseph, L; Kearney, M; Bowler, J; Williams, M A J; Cooper, S; Donnellan, S C; Keogh, J S; Leys, R; Melville, J; Murphy, D J; Porch, N; Wyrwoll, K-H

    2008-10-01

    The integration of phylogenetics, phylogeography and palaeoenvironmental studies is providing major insights into the historical forces that have shaped the Earth's biomes. Yet our present view is biased towards arctic and temperate/tropical forest regions, with very little focus on the extensive arid regions of the planet. The Australian arid zone is one of the largest desert landform systems in the world, with a unique, diverse and relatively well-studied biota. With foci on palaeoenvironmental and molecular data, we here review what is known about the assembly and maintenance of this biome in the context of its physical history, and in comparison with other mesic biomes. Aridification of Australia began in the Mid-Miocene, around 15 million years, but fully arid landforms in central Australia appeared much later, around 1-4 million years. Dated molecular phylogenies of diverse taxa show the deepest divergences of arid-adapted taxa from the Mid-Miocene, consistent with the onset of desiccation. There is evidence of arid-adapted taxa evolving from mesic-adapted ancestors, and also of speciation within the arid zone. There is no evidence for an increase in speciation rate during the Pleistocene, and most arid-zone species lineages date to the Pliocene or earlier. The last 0.8 million years have seen major fluctuations of the arid zone, with large areas covered by mobile sand dunes during glacial maxima. Some large, vagile taxa show patterns of recent expansion and migration throughout the arid zone, in parallel with the ice sheet-imposed range shifts in Northern Hemisphere taxa. Yet other taxa show high lineage diversity and strong phylogeographical structure, indicating persistence in multiple localised refugia over several glacial maxima. Similar to the Northern Hemisphere, Pleistocene range shifts have produced suture zones, creating the opportunity for diversification and speciation through hybridisation, polyploidy and parthenogenesis. This review highlights

  17. NEE and GPP dynamic evolution at two biomes in the upper Spanish plateau

    Science.gov (United States)

    Sánchez, María Luisa; Pardo, Nuria; Pérez, Isidro Alberto; García, Maria de los Angeles

    2014-05-01

    In order to assess the ability of dominant biomes to act as a CO2 sink, two eddy correlation stations close to each other in central Spain have been concurrently operational since March 2008 until the present. The land use of the first station, AC, is a rapeseed rotating crop consisting of annual rotation of non-irrigated rapeseed, barley, peas, rye, and sunflower, respectively. The land use of the second, CIBA, is a mixture of open shrubs/crops, with open shrubs being markedly dominant. The period of measurements covered variable general meteorological conditions. 2009 and 2012 were dominated by drought, whereas 2010 was the rainiest year. Annual rainfall during 2008 and 2009 was close to the historical averaged annual means. This paper presents the dynamic evolution of NEE-8d and GPP-8d observed at the AC station over five years and compares the results with those concurrently observed at the CIBA station. GGP 8-d estimates at both stations were determined using a Light Use Efficiency Model, LUE. Input data for the LUE model were the FPAR 8-d products supplied by MODIS, PAR in situ measurements, and a scalar f, varying between 0 and 1, to take account of the reduction in maximum PAR conversion efficiency, ɛ0, under limiting environmental conditions. f values were assumed to be dependent on air temperature and evaporative fraction, EF, which was considered a proxy of soil moisture. ɛ0, a key parameter, which depends on land use types, was derived through the results of a linear regression fit between the GPP 8-d eddy covariance composites observed and the LUE concurrent 8-d model estimates. Over the five-year study period, both biomes behaved as CO2 sinks. However, the ratio of the NEE-8d total accumulated at AC and CIBA, respectively, was close to a factor two, revealing the effectiveness of the studied crops as CO2 sinks. On an annual basis, accumulated NEE-8d exhibited major variability in both biomes. At CIBA, the results were largely dominated by the

  18. Cancer-related marketing centrality motifs acting as pivot units in the human signaling network and mediating cross-talk between biological pathways.

    Science.gov (United States)

    Li, Wan; Chen, Lina; Li, Xia; Jia, Xu; Feng, Chenchen; Zhang, Liangcai; He, Weiming; Lv, Junjie; He, Yuehan; Li, Weiguo; Qu, Xiaoli; Zhou, Yanyan; Shi, Yuchen

    2013-12-01

    Network motifs in central positions are considered to not only have more in-coming and out-going connections but are also localized in an area where more paths reach the networks. These central motifs have been extensively investigated to determine their consistent functions or associations with specific function categories. However, their functional potentials in the maintenance of cross-talk between different functional communities are unclear. In this paper, we constructed an integrated human signaling network from the Pathway Interaction Database. We identified 39 essential cancer-related motifs in central roles, which we called cancer-related marketing centrality motifs, using combined centrality indices on the system level. Our results demonstrated that these cancer-related marketing centrality motifs were pivotal units in the signaling network, and could mediate cross-talk between 61 biological pathways (25 could be mediated by one motif on average), most of which were cancer-related pathways. Further analysis showed that molecules of most marketing centrality motifs were in the same or adjacent subcellular localizations, such as the motif containing PI3K, PDK1 and AKT1 in the plasma membrane, to mediate signal transduction between 32 cancer-related pathways. Finally, we analyzed the pivotal roles of cancer genes in these marketing centrality motifs in the pathogenesis of cancers, and found that non-cancer genes were potential cancer-related genes.

  19. Microbial Community and Biochemical Dynamics of Biological Soil Crusts across a Gradient of Surface Coverage in the Central Mojave Desert.

    Science.gov (United States)

    Mogul, Rakesh; Vaishampayan, Parag; Bashir, Mina; McKay, Chris P; Schubert, Keith; Bornaccorsi, Rosalba; Gomez, Ernesto; Tharayil, Sneha; Payton, Geoffrey; Capra, Juliana; Andaya, Jessica; Bacon, Leonard; Bargoma, Emily; Black, David; Boos, Katie; Brant, Michaela; Chabot, Michael; Chau, Danny; Cisneros, Jessica; Chu, Geoff; Curnutt, Jane; DiMizio, Jessica; Engelbrecht, Christian; Gott, Caroline; Harnoto, Raechel; Hovanesian, Ruben; Johnson, Shane; Lavergne, Britne; Martinez, Gabriel; Mans, Paul; Morales, Ernesto; Oei, Alex; Peplow, Gary; Piaget, Ryan; Ponce, Nicole; Renteria, Eduardo; Rodriguez, Veronica; Rodriguez, Joseph; Santander, Monica; Sarmiento, Khamille; Scheppelmann, Allison; Schroter, Gavin; Sexton, Devan; Stephenson, Jenin; Symer, Kristin; Russo-Tait, Tatiane; Weigel, Bill; Wilhelm, Mary B

    2017-01-01

    In this study, we expand upon the biogeography of biological soil crusts (BSCs) and provide molecular insights into the microbial community and biochemical dynamics along the vertical BSC column structure, and across a transect of increasing BSC surface coverage in the central Mojave Desert, CA, United States. Next generation sequencing reveals a bacterial community profile that is distinct among BSCs in the southwestern United States. Distribution of major phyla in the BSC topsoils included Cyanobacteria (33 ± 8%), Proteobacteria (26 ± 6%), and Chloroflexi (12 ± 4%), with Phormidium being the numerically dominant genus. Furthermore, BSC subsurfaces contained Proteobacteria (23 ± 5%), Actinobacteria (20 ± 5%), and Chloroflexi (18 ± 3%), with an unidentified genus from Chloroflexi (AKIW781, order) being numerically dominant. Across the transect, changes in distribution at the phylum ( p < 0.0439) and genus ( p < 0.006) levels, including multiple biochemical and geochemical trends ( p < 0.05), positively correlated with increasing BSC surface coverage. This included increases in (a) Chloroflexi abundance, (b) abundance and diversity of Cyanobacteria, (b) OTU-level diversity in the topsoil, (c) OTU-level differentiation between the topsoil and subsurface, (d) intracellular ATP abundances and catalase activities, and (e) enrichments in clay, silt, and varying elements, including S, Mn, Co, As, and Pb, in the BSC topsoils. In sum, these studies suggest that BSCs from regions of differing surface coverage represent early successional stages, which exhibit increasing bacterial diversity, metabolic activities, and capacity to restructure the soil. Further, these trends suggest that BSC successional maturation and colonization across the transect are inhibited by metals/metalloids such as B, Ca, Ti, Mn, Co, Ni, Mo, and Pb.

  20. Effect of habitat disturbance on pollination biology of the columnar cactus Stenocereus quevedonis at landscape-level in central Mexico.

    Science.gov (United States)

    Rodríguez-Oseguera, A G; Casas, A; Herrerías-Diego, Y; Pérez-Negrón, E

    2013-05-01

    Stenocereus quevedonis ('pitire') is a columnar cactus endemic to central Mexico, grown for its edible fruit. Phenology, pollination biology and behaviour of flower visitors of this species were compared in six conserved and disturbed sites, hypothesising that: (i) pitire pollination is self-incompatible, requiring animal vectors; (ii) higher incidence of radiation on plants in cleared forest may lead to a higher number of flowers per pitire plant and longer blooming season, and disturbing and differential spatial availability of flower resources may determine differential attraction of pollinators to conserved and disturbed areas; (iii) if pitire pollination system is specialised, reproductive success would decrease with pollinator scarcity, or other species may substitute for main pollinators. In all sites, pitire reproduction started in January, flowering peak occurring in April, anthesis duration was 15 h and predominantly nocturnal (9 h), pollen was released at 23:00 h, nectar was produced throughout anthesis, and breeding system was self-incompatible. Flower production per plant was similar in disturbed and conserved sites, but flower availability was higher (because of higher tree density) and longer in disturbed sites. Pollination is nocturnal, the most frequent legitimate pollinator being the bat Leptonycteris yerbabuenae; diurnal pollination is rare but possible, carried out by bee species. Fruit and seed set in control and nocturnal pollination treatments at disturbed sites were higher than in conserved sites. Frequency of L. yerbabuenae visits was similar among site types, but more visits of complementary nocturnal and diurnal pollinators were recorded in disturbed sites, which could explain differences in reproductive success. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. Microbial Community and Biochemical Dynamics of Biological Soil Crusts across a Gradient of Surface Coverage in the Central Mojave Desert

    Directory of Open Access Journals (Sweden)

    Rakesh Mogul

    2017-10-01

    Full Text Available In this study, we expand upon the biogeography of biological soil crusts (BSCs and provide molecular insights into the microbial community and biochemical dynamics along the vertical BSC column structure, and across a transect of increasing BSC surface coverage in the central Mojave Desert, CA, United States. Next generation sequencing reveals a bacterial community profile that is distinct among BSCs in the southwestern United States. Distribution of major phyla in the BSC topsoils included Cyanobacteria (33 ± 8%, Proteobacteria (26 ± 6%, and Chloroflexi (12 ± 4%, with Phormidium being the numerically dominant genus. Furthermore, BSC subsurfaces contained Proteobacteria (23 ± 5%, Actinobacteria (20 ± 5%, and Chloroflexi (18 ± 3%, with an unidentified genus from Chloroflexi (AKIW781, order being numerically dominant. Across the transect, changes in distribution at the phylum (p < 0.0439 and genus (p < 0.006 levels, including multiple biochemical and geochemical trends (p < 0.05, positively correlated with increasing BSC surface coverage. This included increases in (a Chloroflexi abundance, (b abundance and diversity of Cyanobacteria, (b OTU-level diversity in the topsoil, (c OTU-level differentiation between the topsoil and subsurface, (d intracellular ATP abundances and catalase activities, and (e enrichments in clay, silt, and varying elements, including S, Mn, Co, As, and Pb, in the BSC topsoils. In sum, these studies suggest that BSCs from regions of differing surface coverage represent early successional stages, which exhibit increasing bacterial diversity, metabolic activities, and capacity to restructure the soil. Further, these trends suggest that BSC successional maturation and colonization across the transect are inhibited by metals/metalloids such as B, Ca, Ti, Mn, Co, Ni, Mo, and Pb.

  2. Tritium labeling for bio-med research

    International Nuclear Information System (INIS)

    Lemmon, R.M.

    1980-01-01

    A very large fraction of what we know about biochemical pathways in the living cell has resulted from the use of radioactively-labeled tracer compounds; the use of tritium-labeled compounds has been particularly important. As research in biochemistry and biology has progressed the need has arisen to label compounds of higher specific activity and of increasing molecular complexity - for example, oligo-nucleotides, polypeptides, hormones, enzymes. Our laboratory has gradually developed special facilities for handling tritium at the kilocurie level. These facilities have already proven extremely valuable in producing labeled compounds that are not available from commercial sources. The principal ways employed for compound labeling are: (1) microwave discharge labeling, (2) catalytic tritio-hydrogenation, (3) catalytic exchange with T 2 O, and (4) replacement of halogen atoms by T. Studies have also been carried out on tritiation by the replacement of halogen atoms with T atoms. These results indicate that carrier-free tritium-labeled products, including biomacromolecules, can be produced in this way

  3. BIOME: A browser-aware search and order system

    Science.gov (United States)

    Grubb, Jon W.; Jennings, Sarah V.; Yow, Teresa G.; Daughterty, Patricia F.

    1996-01-01

    The Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC), which is associated with NASA's Earth Observing System Data and Information System (EOSDIS), provides access to a large number of tabular and imagery datasets used in ecological and environmental research. Because of its large and diverse data holdings, the challenge for the ORNL DAAC is to help users find data of interest from the hundreds of thousands of files available at the DAAC without overwhelming them. Therefore, the ORNL DAAC developed the Biogeochemical Information Ordering Management Environment (BIOME), a search and order system for the World Wide Web (WWW). The WWW provides a new vehicle that allows a wide range of users access to the data. This paper describes the specialized attributes incorporated into BIOME that allow researchers easy access to an otherwise bewildering array of data products.

  4. Biología reproductiva del águila Geranoaetus melanoleucus (Aves: Accipitridae en Chile central Breeding biology of the black-chested eagle Geranoaetus melanoleucus (Aves: Accipitridae in central Chile

    Directory of Open Access Journals (Sweden)

    EDUARDO F. PAVEZ

    2001-09-01

    Full Text Available Durante dos años (julio 1987­enero 1989 se estudió la biología reproductiva del águila (Geranoaetus melanoleucus en San Carlos de Apoquindo, en Chile central. El inicio del período reproductivo se evidenció por un aumento del número de vuelos en pareja. Los cortejos incluyeron vuelos sincronizados de la pareja, capturas, transporte de material al nido y cópulas. Los traspasos de presas ocurrieron durante todo el año, aunque fuera del período reproductivo fueron escasos y forzados por la hembra. Se localizaron 4,7 nidos pareja-1, lo que está en el límite superior documentado para grandes águilas. Fuera del período reproductivo las águilas visitaron ocasionalmente los nidos. Antes de la postura el macho visitó el nido con mayor frecuencia y por menos tiempo que la hembra. En las tres parejas estudiadas se observó visitas a nidos alternativos, con aporte de material y presas. Se promedió 2,3 huevos postura-1 (DE = 0,5, n = 6, incubando macho y hembra, y eclosionando el 100 %. A los 25 días de edad comenzaron a emerger las plumas de vuelo de los pollos, a los 35 días comían solos las presas aportadas al nido y a los 59 días abandonaron el nido. Durante la crianza la hembra permaneció más tiempo en el nido que el macho, con una tendencia de los adultos a disminuir el tiempo de permanencia en el nido. El 79 % de los pollos sobrevivió a la crianza, lo que se puede considerar un éxito reproductivo elevado, y que se explicaría por la elevada disponibilidad de presas en el sitio de estudio, particularmente de conejos. Los pollos permanecieron en el territorio paterno 10 meses, lo que coincidió con la siguiente postura de huevos, disminuyendo gradualmente su presencia en el área y aumentando la intolerancia de los adultos hacia sus hijos. Los resultados presentados se corresponden con el patrón descrito en la literatura para otras águilasThe breeding biology of the black-chested eagle (Geranoaetus melanoleucus was studied

  5. Pennsylvanian coniferopsid forests in sabkha facies reveal the nature of seasonal tropical biome

    Science.gov (United States)

    Falcon-Lang, H. J.; Jud, N.A.; John, Nelson W.; DiMichele, W.A.; Chaney, D.S.; Lucas, S.G.

    2011-01-01

    Pennsylvanian fossil forests are known from hundreds of sites across tropical Pangea, but nearly all comprise remains of humid Coal Forests. Here we report a unique occurrence of seasonally dry vegetation, preserved in growth position along >5 km of strike, in the Pennsylvanian (early Kasimovian, Missourian) of New Mexico (United States). Analyses of stump anatomy, diameter, and spatial density, coupled with observations of vascular traces and associated megaflora, show that this was a deciduous, mixed-age, coniferopsid woodland (~100 trees per hectare) with an open canopy. The coniferopsids colonized coastal sabkha facies and show tree rings, confirming growth under seasonally dry conditions. Such woodlands probably served as the source of coniferopsids that replaced Coal Forests farther east in central Pangea during drier climate phases. Thus, the newly discovered woodland helps unravel biome-scale vegetation dynamics and allows calibration of climate models. ?? 2011 Geological Society of America.

  6. Multiple nutrient stresses at intersecting Pacific Ocean biomes detected by protein biomarkers.

    Science.gov (United States)

    Saito, Mak A; McIlvin, Matthew R; Moran, Dawn M; Goepfert, Tyler J; DiTullio, Giacomo R; Post, Anton F; Lamborg, Carl H

    2014-09-05

    Marine primary productivity is strongly influenced by the scarcity of required nutrients, yet our understanding of these nutrient limitations is informed by experimental observations with sparse geographical coverage and methodological limitations. We developed a quantitative proteomic method to directly assess nutrient stress in high-light ecotypes of the abundant cyanobacterium Prochlorococcus across a meridional transect in the central Pacific Ocean. Multiple peptide biomarkers detected widespread and overlapping regions of nutritional stress for nitrogen and phosphorus in the North Pacific Subtropical Gyre and iron in the equatorial Pacific. Quantitative protein analyses demonstrated simultaneous stress for these nutrients at biome interfaces. This application of proteomic biomarkers to diagnose ocean metabolism demonstrated Prochlorococcus actively and simultaneously deploying multiple biochemical strategies for low-nutrient conditions in the oceans. Copyright © 2014, American Association for the Advancement of Science.

  7. Parameterisation of Biome BGC to assess forest ecosystems in Africa

    Science.gov (United States)

    Gautam, Sishir; Pietsch, Stephan A.

    2010-05-01

    African forest ecosystems are an important environmental and economic resource. Several studies show that tropical forests are critical to society as economic, environmental and societal resources. Tropical forests are carbon dense and thus play a key role in climate change mitigation. Unfortunately, the response of tropical forests to environmental change is largely unknown owing to insufficient spatially extensive observations. Developing regions like Africa where records of forest management for long periods are unavailable the process-based ecosystem simulation model - BIOME BGC could be a suitable tool to explain forest ecosystem dynamics. This ecosystem simulation model uses descriptive input parameters to establish the physiology, biochemistry, structure, and allocation patterns within vegetation functional types, or biomes. Undocumented parameters for larger-resolution simulations are currently the major limitations to regional modelling in African forest ecosystems. This study was conducted to document input parameters for BIOME-BGC for major natural tropical forests in the Congo basin. Based on available literature and field measurements updated values for turnover and mortality, allometry, carbon to nitrogen ratios, allocation of plant material to labile, cellulose, and lignin pools, tree morphology and other relevant factors were assigned. Daily climate input data for the model applications were generated using the statistical weather generator MarkSim. The forest was inventoried at various sites and soil samples of corresponding stands across Gabon were collected. Carbon and nitrogen in the collected soil samples were determined from soil analysis. The observed tree volume, soil carbon and soil nitrogen were then compared with the simulated model outputs to evaluate the model performance. Furthermore, the simulation using Congo Basin specific parameters and generalised BIOME BGC parameters for tropical evergreen broadleaved tree species were also

  8. Softball Games Bring NCI and Leidos Biomed Employees Together | Poster

    Science.gov (United States)

    NCI and Leidos Biomed employees took to the fields at Nallin Pond for the third annual slow-pitch softball games on August 26. The series attracted 54 employees who were divided into four teams, Red, Blue, Gray, and White, and they were cheered on by about 40 enthusiastic spectators. In the first set of games, the Gray team defeated the Blue team, 15–8, and the White team

  9. Pollen-based biome reconstructions for Latin America at 0, 6000 and 18 000 radiocarbon years ago

    Science.gov (United States)

    Marchant, R.; Cleef, A.; Harrison, S.P.; Hooghiemstra, H.; Markgraf, Vera; Van Boxel, J.; Ager, T.; Almeida, L.; Anderson, R.; Baied, C.; Behling, H.; Berrio, J.C.; Burbridge, R.; Bjorck, S.; Byrne, R.; Bush, M.; Duivenvoorden, J.; Flenley, J.; De Oliveira, P.; Van Gee, B.; Graf, K.; Gosling, W.D.; Harbele, S.; Van Der Hammen, T.; Hansen, B.; Horn, S.; Kuhry, P.; Ledru, M.-P.; Mayle, F.; Leyden, B.; Lozano-Garcia, S.; Melief, A.M.; Moreno, P.; Moar, N.T.; Prieto, A.; Van Reenen, G.; Salgado-Labouriau, M.; Schabitz, F.; Schreve-Brinkman, E. J.; Wille, M.

    2009-01-01

    The biomisation method is used to reconstruct Latin American vegetation at 6000??500 and 18 000??1000 radiocarbon years before present ( 14C yr BP) from pollen data. Tests using modern pollen data from 381 samples derived from 287 locations broadly reproduce potential natural vegetation. The strong temperature gradient associated with the Andes is recorded by a transition from high altitude cool grass/shrubland and cool mixed forest to mid-altitude cool temperate rain forest, to tropical dry, seasonal and rain forest at low altitudes. Reconstructed biomes from a number of sites do not match the potential vegetation due to local factors such as human impact, methodological artefacts and mechanisms of pollen representivity of the parent vegetation. At 6000??500 14C yr BP 255 samples are analysed from 127 sites. Differences between the modern and the 6000??500 14C yr BP reconstruction are comparatively small; change relative to the modern reconstruction are mainly to biomes characteristic of drier climate in the north of the region with a slight more mesic shift in the south. Cool temperate rain forest remains dominant in western South America. In northwestern South America a number of sites record transitions from tropical seasonal forest to tropical dry forest and tropical rain forest to tropical seasonal forest. Sites in Central America show a change in biome assignment, but to more mesic vegetation, indicative of greater plant available moisture, e.g. on the Yucat??n peninsula sites record warm evergreen forest, replacing tropical dry forest and warm mixed forest presently recorded. At 18 000??1000 14C yr BP 61 samples from 34 sites record vegetation reflecting a generally cool and dry environment. Cool grass/shrubland is prevalent in southeast Brazil whereas Amazonian sites record tropical dry forest, warm temperate rain forest and tropical seasonal forest. Southernmost South America is dominated by cool grass/shrubland, a single site retains cool temperate rain

  10. Constrained variability of modeled T:ET ratio across biomes

    Science.gov (United States)

    Fatichi, Simone; Pappas, Christoforos

    2017-07-01

    A large variability (35-90%) in the ratio of transpiration to total evapotranspiration (referred here as T:ET) across biomes or even at the global scale has been documented by a number of studies carried out with different methodologies. Previous empirical results also suggest that T:ET does not covary with mean precipitation and has a positive dependence on leaf area index (LAI). Here we use a mechanistic ecohydrological model, with a refined process-based description of evaporation from the soil surface, to investigate the variability of T:ET across biomes. Numerical results reveal a more constrained range and higher mean of T:ET (70 ± 9%, mean ± standard deviation) when compared to observation-based estimates. T:ET is confirmed to be independent from mean precipitation, while it is found to be correlated with LAI seasonally but uncorrelated across multiple sites. Larger LAI increases evaporation from interception but diminishes ground evaporation with the two effects largely compensating each other. These results offer mechanistic model-based evidence to the ongoing research about the patterns of T:ET and the factors influencing its magnitude across biomes.

  11. Organochlorine compounds in streambed sediment and in biological tissue from streams and their relations to land use, central Arizona

    Science.gov (United States)

    Gebler, Joseph B.

    2000-01-01

    Streambed-sediment samples from 13 sites and biological-tissue samples from 11 sites in the Gila River Basin in central Arizona were analyzed for 32 organochlorine compounds in streambed sediment and 28 compounds in biological tissue during 1996 as part of the U.S. Geological Survey's National Water-Quality Assessment program. The objectives of the study were to determine the occurrence and distribution of organochlorine compounds and their relation to land use. Sampling sites were categorized on the basis of major land uses in the basin or the source of water in the stream. Because land uses were mixed or had changed over time, some land-use categories were combined. Sites were categorized as forest/rangeland (6), forest/urban (1), urban (4), or agricultural/urban (2). Thirteen organochlorine compounds were detected in streambed-sediment samples, and 10 were detected in tissue samples. The number of compounds found in streambed-sediment samples from individual sites ranged from 0 to 10, and the range for individual tissue samples was 0 to 7. Comparison of the number of detections in streambed-sediment samples to the number of detections in tissue samples from particular sites where both were sampled yielded five instances where more compounds were detected in streambed sediment, six instances where more compounds were detected in tissue, and five instances where the number of detections in streambed sediment and tissue were equal. The frequency of detection of particular compounds for sites where both streambed sediment and tissue were sampled resulted in five compounds being detected more frequently in streambed sediment, five more frequently in tissue, and three compounds that were equally frequent in streambed sediment and in tissue. Few contaminants were detected in samples from the forest/rangeland sites; greater numbers of compounds were detected at the urban sites and at the forest/urban site. The greatest number of compounds and the highest concentrations

  12. A dated phylogeny and collection records reveal repeated biome shifts in the African genus Coccinia (Cucurbitaceae).

    Science.gov (United States)

    Holstein, Norbert; Renner, Susanne S

    2011-01-26

    Conservatism in climatic tolerance may limit geographic range expansion and should enhance the effects of habitat fragmentation on population subdivision. Here we study the effects of historical climate change, and the associated habitat fragmentation, on diversification in the mostly sub-Saharan cucurbit genus Coccinia, which has 27 species in a broad range of biota from semi-arid habitats to mist forests. Species limits were inferred from morphology, and nuclear and plastid DNA sequence data, using multiple individuals for the widespread species. Climatic tolerances were assessed from the occurrences of 1189 geo-referenced collections and WorldClim variables. Nuclear and plastid gene trees included 35 or 65 accessions, representing up to 25 species. The data revealed four species groups, one in southern Africa, one in Central and West African rain forest, one widespread but absent from Central and West African rain forest, and one that occurs from East Africa to southern Africa. A few individuals are differently placed in the plastid and nuclear (LFY) trees or contain two ITS sequence types, indicating hybridization. A molecular clock suggests that the diversification of Coccinia began about 6.9 Ma ago, with most of the extant species diversity dating to the Pliocene. Ancestral biome reconstruction reveals six switches between semi-arid habitats, woodland, and forest, and members of several species pairs differ significantly in their tolerance of different precipitation regimes. The most surprising findings of this study are the frequent biome shifts (in a relatively small clade) over just 6 - 7 million years and the limited diversification during and since the Pleistocene. Pleistocene climate oscillations may have been too rapid or too shallow for full reproductive barriers to develop among fragmented populations of Coccinia, which would explain the apparently still ongoing hybridization between certain species. Steeper ecological gradients in East Africa and

  13. A dated phylogeny and collection records reveal repeated biome shifts in the African genus Coccinia (Cucurbitaceae

    Directory of Open Access Journals (Sweden)

    Renner Susanne S

    2011-01-01

    Full Text Available Abstract Background Conservatism in climatic tolerance may limit geographic range expansion and should enhance the effects of habitat fragmentation on population subdivision. Here we study the effects of historical climate change, and the associated habitat fragmentation, on diversification in the mostly sub-Saharan cucurbit genus Coccinia, which has 27 species in a broad range of biota from semi-arid habitats to mist forests. Species limits were inferred from morphology, and nuclear and plastid DNA sequence data, using multiple individuals for the widespread species. Climatic tolerances were assessed from the occurrences of 1189 geo-referenced collections and WorldClim variables. Results Nuclear and plastid gene trees included 35 or 65 accessions, representing up to 25 species. The data revealed four species groups, one in southern Africa, one in Central and West African rain forest, one widespread but absent from Central and West African rain forest, and one that occurs from East Africa to southern Africa. A few individuals are differently placed in the plastid and nuclear (LFY trees or contain two ITS sequence types, indicating hybridization. A molecular clock suggests that the diversification of Coccinia began about 6.9 Ma ago, with most of the extant species diversity dating to the Pliocene. Ancestral biome reconstruction reveals six switches between semi-arid habitats, woodland, and forest, and members of several species pairs differ significantly in their tolerance of different precipitation regimes. Conclusions The most surprising findings of this study are the frequent biome shifts (in a relatively small clade over just 6 - 7 million years and the limited diversification during and since the Pleistocene. Pleistocene climate oscillations may have been too rapid or too shallow for full reproductive barriers to develop among fragmented populations of Coccinia, which would explain the apparently still ongoing hybridization between certain

  14. Biología reproductiva de Anisotremus interruptus (Perciformes: Haemulidae en el Pacífico central mexicano Reproductive biology of Anisotremus interruptus (Perciformes: Haemulidae in the Mexican Central Pacific

    Directory of Open Access Journals (Sweden)

    Salvador Ruiz-Ramírez

    2012-06-01

    Full Text Available Anisotremus interruptus es una especie de importancia económica que se distribuye ampliamente en el Pacífico oriental. Para investigar las características de la reproducción de esta especie, se realizó un estudio a lo largo de varios años en la costa de Jalisco, México. Para este fin, se tomaron muestras entre 1998 y 2008 con redes de enmalle de diferente luz de malla. Asimismo, se recolectaron en total 1 090 organismos que presentaron un intervalo de longitud total de 15.6-61.0cm. Además, se observó una diferencia significativa con respecto al valor esperado de 1:1 en la proporción de hembras y machos para todos los organismos recolectados y por clase de talla, pero no se encontró diferencia en dicha proporción en los análisis entre meses y entre años. La distribución temporal del índice gonadosomático y de la proporción de estadios de maduración gonadal sugieren que el periodo de reproducción en A. interruptus se concentra principalmente entre febrero-mayo, aunque se registraron desoves de menor intensidad en otros meses. También, se identificaron siete fases de desarrollo de los ovocitos. En ovarios de estadio maduro, se observaron ovocitos en diferente fase de desarrollo, lo cual sugiere que el desarrollo ovárico es de tipo asincrónico. La organización interna del testículo es del tipo lobular. La longitud de maduración sexual (L50 para las hembras fue de 31.0cm y para los machos de 29.7cm.Reproductive biology of Anisotremus interruptus (Perciformes: Haemulidae in the Mexican Central Pacific. Anisotremus interruptus is a widely distributed and commercially important species in the Eastern Pacific. A multi-year research on the reproduction of this species was carried out in coastal waters of Jalisco, Mexico. For this purpose, monthly samples were gathered with gillnets of different mesh sizes from 1998-2008. A total of 1 090 individuals were collected with a total length range between 15.6-61.0cm. Significant

  15. Biología reproductiva del pargo Lutjanus inermis (Perciformes: Lutjanidae, en el Pacífico central mexicano Reproductive biology of the Golden snapper Lutjanus inermis (Perciformes: Lutjanidae in the central Mexican Pacific

    Directory of Open Access Journals (Sweden)

    Gabriela Lucano-Ramírez

    2012-03-01

    Full Text Available Debido a los escasos antecedentes del efecto de las pesquerías y manejo del pargo Lutjanus inermis, es importante conocer la época reproductiva para el establecimiento de temporadas de veda, ya que la biomasa de los peces en fase de reproducción, es usada como punto de referencia para evaluar la condición del stock explotado y para establecer futuros niveles de captura. Por ello, el objetivo de este trabajo fue analizar algunos aspectos reproductivos como proporción sexual, época reproductiva, talla de madurez de L. inermis en las costas de Jalisco, México. Durante 1999-2008, se llevaron a cabo muestreos mensuales de los ejemplares capturados por la pesca artesanal en las bahías de Navidad, Tenacatita y Chamela (Jalisco, México. Se recolectaron 311 (53.1% hembras y 275 (46.9% machos y, la proporción de sexos (1:0.88 no presentó diferencia significativa. El intervalo de longitud total fue 14.4 a 37.0cm y el peso total de 48 a 575g. L. inermis presentó los máximos valores del IGS en dos periodos, febrero-abril y septiembre-noviembre, también en estos periodos se presentaron los mayores porcentajes de organismos en estadio de maduración. El ovario presentó el tipo de desarrollo asincrónico y se reconocieron siete fases del desarrollo de los ovocitos. En los testículos se observó el tipo de desarrollo lobular, se observaron espermatozoides en el centro de los cistos y en el conducto recolector. La talla de madurez (L50 fue de 23.9cm LT para hembras y 23.6cm LT para machos. Considerando el periodo de muestreo de este estudio, los antecedentes descritos podrían ser de utilidad en la formulación de planes o estrategias de manejo de esta especie.Reproductive biology of the Golden snapper Lutjanus inermis (Perciformes: Lutjanidae in the central Mexican Pacific. Reproductive aspects and information on the effect of fishery activities over this species stock are scarce, despite the imperative need of effective protection and resource

  16. BioM2MetDisease: a manually curated database for associations between microRNAs, metabolites, small molecules and metabolic diseases.

    Science.gov (United States)

    Xu, Yanjun; Yang, Haixiu; Wu, Tan; Dong, Qun; Sun, Zeguo; Shang, Desi; Li, Feng; Xu, Yingqi; Su, Fei; Liu, Siyao; Zhang, Yunpeng; Li, Xia

    2017-01-01

    BioM2MetDisease is a manually curated database that aims to provide a comprehensive and experimentally supported resource of associations between metabolic diseases and various biomolecules. Recently, metabolic diseases such as diabetes have become one of the leading threats to people’s health. Metabolic disease associated with alterations of multiple types of biomolecules such as miRNAs and metabolites. An integrated and high-quality data source that collection of metabolic disease associated biomolecules is essential for exploring the underlying molecular mechanisms and discovering novel therapeutics. Here, we developed the BioM2MetDisease database, which currently documents 2681 entries of relationships between 1147 biomolecules (miRNAs, metabolites and small molecules/drugs) and 78 metabolic diseases across 14 species. Each entry includes biomolecule category, species, biomolecule name, disease name, dysregulation pattern, experimental technique, a brief description of metabolic disease-biomolecule relationships, the reference, additional annotation information etc. BioM2MetDisease provides a user-friendly interface to explore and retrieve all data conveniently. A submission page was also offered for researchers to submit new associations between biomolecules and metabolic diseases. BioM2MetDisease provides a comprehensive resource for studying biology molecules act in metabolic diseases, and it is helpful for understanding the molecular mechanisms and developing novel therapeutics for metabolic diseases. http://www.bio-bigdata.com/BioM2MetDisease/. © The Author(s) 2017. Published by Oxford University Press.

  17. Use of BIOME-BGC to simulate water and carbon fluxes within Mediterranean macchia

    OpenAIRE

    Chiesi M; Chirici G; Corona P; Duce P; Salvati R; Spano D; Vaccari FP; Maselli F

    2012-01-01

    The biogeochemical model BIOME-BGC is capable to estimate the main ecophysiological processes characterising all terrestrial ecosystems. To this aim it needs to be properly adapted to reproduce the behaviour of each biome type through a calibration phase. The aim of this paper is to adapt BIOME-BGC to reproduce the evapotranspiration (ET) and photosynthesis (GPP) of Mediterranean macchia spread all over Italy. Ten different sites were selected in the Centre-South of Italy and their gross prim...

  18. Evaluating fire danger in Brazilian biomes: present and future patterns

    Science.gov (United States)

    Silva, Patrícia; Bastos, Ana; DaCamara, Carlos; Libonati, Renata

    2017-04-01

    Climate change is expected to have a significant impact on fire occurrence and activity, particularly in Brazil, a region known to be fire-prone [1]. The Brazilian savanna, commonly referred to as cerrado, is a fire-adapted biome covering more than 20% of the country's total area. It presents the highest numbers of fire events, making it particularly susceptible to changes in climate. It is thus essential to understand the present fire regimes in Brazilian biomes, in order to better evaluate future patterns. The CPTEC/INPE, the Brazilian Center for Weather Forecasting and Climate Research at the Brazilian National Institute of Space Research developed a fire danger index based on the occurrence of hundreds of thousands of fire events in the main Brazilian biomes [2]: the Meteorological Fire Danger Index (MFDI). This index indicates the predisposition of vegetation to be burned on a given day, for given climate conditions preceding that day. It relies on daily values of air temperature, relative humidity, accumulated precipitation and vegetation cover. In this study we aim to access the capability of the MFDI to accurately replicate present fire conditions for different biomes, with a special focus on cerrado. To this end, we assess the link between the MFDI as calculated by three different reanalysis (ERA-Interim, NCEP/DOE Reanalysis 2 and MERRA-2) and the observed burned area. We further calculate the validated MFDI using a regional climate model, the RCA4 as forced by EC-Earth from CORDEX, to understand the ability of the model to characterize present fire danger. Finally, the need to calibrate the model to better characterize future fire danger was also evaluated. This work was developed within the framework of the Brazilian Fire-Land-Atmosphere System (BrFLAS) Project financed by the Portuguese and Brazilian science foundations, FCT and FAPESP (project references FAPESP/1389/2014 and 2014/20042-2). [1] KRAWCHUK, M.A.; MORITZ, M.A.; PARISIEN, M.A.; VAN DORN, J

  19. [Logistics of collection and transportation of biological samples and the organization of the central laboratory in the ELSA-Brasil].

    Science.gov (United States)

    Fedeli, Ligia G; Vidigal, Pedro G; Leite, Claudia Mendes; Castilhos, Cristina D; Pimentel, Robércia Anjos; Maniero, Viviane C; Mill, Jose Geraldo; Lotufo, Paulo A; Pereira, Alexandre C; Bensenor, Isabela M

    2013-06-01

    The ELSA (Estudo Longitudinal de Saúde do Adulto - Brazilian Longitudinal Study for Adult Health) is a multicenter cohort study which aims at the identification of risk factors associated with type 2 diabetes and cardiovascular diseases in the Brazilian population. The paper describes the strategies for the collection, processing, transportation, and quality control of blood and urine tests in the ELSA. The study decided to centralize the tests at one single laboratory. The processing of the samples was performed at the local laboratories, reducing the weight of the material to be transported, and diminishing the costs of transportation to the central laboratory at the Universidade de São Paulo Hospital. The study included tests for the evaluation of diabetes, insulin resistance, dyslipidemia, electrolyte abnormalities, thyroid hormones, uric acid, hepatic enzyme abnormalities, inflammation, and total blood cell count. In addition, leukocyte DNA, urine, plasma and serum samples were stored. The central laboratory performed approximately 375,000 tests.

  20. The design and synthesis of biologically active organophosphorus compounds--the role of a central research laboratory.

    Science.gov (United States)

    Hall, Roger G

    2010-01-01

    The properties and benefits offered by incorporating phosphorus into molecules are varied and numerous as shown by the many divisional research programs within Ciba-Geigy in the early eighties. This paper describes how a Central Research Group developed new materials in organophosphorous chemistry and identified new leads for life science applications.

  1. Ticks parasitizing bats (Mammalia: Chiroptera) in the Caatinga Biome, Brazil.

    Science.gov (United States)

    Luz, Hermes Ribeiro; Muñoz-Leal, Sebastián; Almeida, Juliana Cardoso de; Faccini, João Luiz Horacio; Labruna, Marcelo Bahia

    2016-01-01

    In this paper, the authors report ticks parasitizing bats from the Serra das Almas Natural Reserve (RPPN) located in the municipality of Crateús, state of Ceará, in the semiarid Caatinga biome of northeastern Brazil. The study was carried out during nine nights in the dry season (July 2012) and 10 nights in the rainy season (February 2013). Only bats of the Phyllostomidae and Mormoopidae families were parasitized by ticks. The species Artibeus planirostris and Carolia perspicillata were the most parasitized. A total of 409 larvae were collected and classified into three genera: Antricola (n = 1), Nothoaspis (n = 1) and Ornithodoros (n = 407). Four species were morphologically identified as Nothoaspis amazoniensis, Ornithodoros cavernicolous, Ornithodoros fonsecai, Ornithodoros hasei, and Ornithodoros marinkellei. Ornithodoros hasei was the most common tick associated with bats in the current study. The present study expand the distributional ranges of at least three soft ticks into the Caatinga biome, and highlight an unexpected richness of argasid ticks inhabiting this arid ecosystem.

  2. Ticks parasitizing bats (Mammalia: Chiroptera in the Caatinga Biome, Brazil

    Directory of Open Access Journals (Sweden)

    Hermes Ribeiro Luz

    Full Text Available Abstract In this paper, the authors report ticks parasitizing bats from the Serra das Almas Natural Reserve (RPPN located in the municipality of Crateús, state of Ceará, in the semiarid Caatinga biome of northeastern Brazil. The study was carried out during nine nights in the dry season (July 2012 and 10 nights in the rainy season (February 2013. Only bats of the Phyllostomidae and Mormoopidae families were parasitized by ticks. The species Artibeus planirostris and Carolia perspicillata were the most parasitized. A total of 409 larvae were collected and classified into three genera: Antricola (n = 1, Nothoaspis (n = 1 and Ornithodoros (n = 407. Four species were morphologically identified as Nothoaspis amazoniensis, Ornithodoros cavernicolous, Ornithodoros fonsecai, Ornithodoros hasei, and Ornithodoros marinkellei. Ornithodoros hasei was the most common tick associated with bats in the current study. The present study expand the distributional ranges of at least three soft ticks into the Caatinga biome, and highlight an unexpected richness of argasid ticks inhabiting this arid ecosystem.

  3. [Clinico-biochemical aspects of human adaptation in central Antarctica as applied to the problems of space biology and medicine].

    Science.gov (United States)

    Kurbanov, V V; Khmel'kov, V P; Krupina, T N; Kuznetscv, A G; Kuz'min, M P

    1977-01-01

    The paper presents the results of clinical, physiological and biochemical examination of 27 polar explorer--members of the 17th Soviet Antartic Expedition at the Vostok station. It gives data on the morbidity rate and describes the development of the asthenic-neurotic syndrome. On the basis of studies of catecholamines and serotonin, the role of the sympatho-adrenal system in the human adaptation to the harsh environments of the Central Antarctica has been shown.

  4. Examining Changes in Central and Peripheral Pain as Mediates of Fatigue Improvement: Results From the British Society for Rheumatology Biologics Register for Rheumatoid Arthritis.

    Science.gov (United States)

    Druce, Katie L; Jones, Gareth T; Macfarlane, Gary J; Basu, Neil

    2016-07-01

    Following anti-tumor necrosis factor (anti-TNF) therapy, improvements in rheumatoid arthritis (RA) fatigue are driven by reductions in pain. However, therapies may modify both central and peripheral pain. This study sought to examine the hypothesis that reductions in fatigue after anti-TNF therapy reflect changes in central, not peripheral, pain mechanisms. Data came from patients with severe baseline fatigue (Short Form 36 health survey [SF-36] vitality scale ≤12.5; n = 2,652), recruited to the British Society for Rheumatology Biologics Register for RA for commencing anti-TNF therapies between October 2000 and November 2008. Data of interest comprised change over 6 months in fatigue, pain (SF-36 bodily pain scale), and disease activity constituents (Disease Activity Score in 28 joints, erythrocyte sedimentation rate [ESR], global health, swollen joints, and tender joints). Principal components factor analysis with varimax rotation determined latent variables of symptom change; variables were accepted provided they had eigenvalues ≥1. Six factors were identified, of which 2 met acceptance criteria (eigenvalues of 2.39 and 1.14, respectively). Following rotation, loadings indicated that factor 1 comprised markers of peripheral inflammation: change in ESR, swollen joints, tender joints, and global health. This distinct loading led to factor 1 being labeled peripheral inflammation. Conversely, factor 2 comprised change in pain, fatigue, and global health and an absence of peripheral inflammation markers and was therefore labeled central inflammation. Following anti-TNF therapies, reductions in fatigue and pain appear to reflect improvements in central, rather than peripheral, inflammation. Therefore, for those seeking to treat fatigue via pain mechanisms, improvements may be maximized by the application of treatment modalities that effectively target central mechanisms. © 2016, American College of Rheumatology.

  5. Pollen-based biome reconstruction for southern Europe and Africa 18,000 yr BP

    NARCIS (Netherlands)

    Elenga, H; Peyron, O; Bonnefille, R; Jolly, D; Cheddadi, R; Guiot, J; Andrieu, [No Value; Bottema, S; Buchet, G; de Beaulieu, JL; Hamilton, AC; Maley, J; Marchant, R; Perez-Obiol, R; Reille, M; Riollet, G; Scott, L; Straka, H; Taylor, D; Van Campo, E; Vincens, A; Laarif, F; Jonson, H

    Pollen data from 18,000 C-14 yr sp were compiled in order to reconstruct biome distributions at the last glacial maximum in southern Europe and Africa. Biome reconstructions were made using the objective biomization method applied to pollen counts using a complete list of dryland taxa wherever

  6. Increasing atmospheric CO2 overrides the historical legacy of multiple stable biome states in Africa.

    Science.gov (United States)

    Moncrieff, Glenn R; Scheiter, Simon; Bond, William J; Higgins, Steven I

    2014-02-01

    The dominant vegetation over much of the global land surface is not predetermined by contemporary climate, but also influenced by past environmental conditions. This confounds attempts to predict current and future biome distributions, because even a perfect model would project multiple possible biomes without knowledge of the historical vegetation state. Here we compare the distribution of tree- and grass-dominated biomes across Africa simulated using a dynamic global vegetation model (DGVM). We explicitly evaluate where and under what conditions multiple stable biome states are possible for current and projected future climates. Our simulation results show that multiple stable biomes states are possible for vast areas of tropical and subtropical Africa under current conditions. Widespread loss of the potential for multiple stable biomes states is projected in the 21st Century, driven by increasing atmospheric CO2 . Many sites where currently both tree-dominated and grass-dominated biomes are possible become deterministically tree-dominated. Regions with multiple stable biome states are widespread and require consideration when attempting to predict future vegetation changes. Testing for behaviour characteristic of systems with multiple stable equilibria, such as hysteresis and dependence on historical conditions, and the resulting uncertainty in simulated vegetation, will lead to improved projections of global change impacts. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  7. Climate change in Inner Mongolia from 1955 to 2005-trends at regional, biome and local scales

    Energy Technology Data Exchange (ETDEWEB)

    Lu, N; Wilske, B; John, R; Chen, J [Department of Environmental Sciences, University of Toledo, Toledo, OH 43606 (United States); Ni, J, E-mail: nan.lu@utoledo.ed, E-mail: burkhard.wilske@utoledo.ed, E-mail: jni@ibcas.ac.c, E-mail: ranjeet.john@utoledo.ed, E-mail: jiquan.chen@utoledo.ed [Alfred Wegener Institute for Polar and Marine Research, Telegrafenberg A43, D-14473 Potsdam (Germany)

    2009-10-15

    This study investigated the climate change in Inner Mongolia based on 51 meteorological stations from 1955 to 2005. The climate data was analyzed at the regional, biome (i.e. forest, grassland and desert) and station scales, with the biome scale as our primary focus. The climate records showed trends of warmer and drier conditions in the region. The annual daily mean, maximum and minimum temperature increased whereas the diurnal temperature range (DTR) decreased. The decreasing trend of annual precipitation was not significant. However, the vapor pressure deficit (VPD) increased significantly. On the decadal scale, the warming and drying trends were more significant in the last 30 years than the preceding 20 years. The climate change varied among biomes, with more pronounced changes in the grassland and the desert biomes than in the forest biome. DTR and VPD showed the clearest inter-biome gradient from the lowest rate of change in the forest biome to the highest rate of change in the desert biome. The rates of change also showed large variations among the individual stations. Our findings correspond with the IPCC predictions that the future climate will vary significantly by location and through time, suggesting that adaptation strategies also need to be spatially viable.

  8. S2Biom database with logistical components of the biomass value chain

    NARCIS (Netherlands)

    Annevelink, E.; Groot, de H.L.E.; Shah, N.; Giarola, S.; Pantaleo, M.; Anttila, P.; Vis, Martijn; Raa, te Rik; Berg, van den Douwe; Gabrielle, B.

    2015-01-01

    The S2Biom project (www.s2biom.eu) - Delivery of sustainable supply of non-food biomass to support
    a resource-efficient Bioeconomy in Europe - supports sustainable delivery chains of non-food biomass feedstock.
    This poses a logistical challenge because the quality and handling

  9. Climate change in Inner Mongolia from 1955 to 2005-trends at regional, biome and local scales

    International Nuclear Information System (INIS)

    Lu, N; Wilske, B; John, R; Chen, J; Ni, J

    2009-01-01

    This study investigated the climate change in Inner Mongolia based on 51 meteorological stations from 1955 to 2005. The climate data was analyzed at the regional, biome (i.e. forest, grassland and desert) and station scales, with the biome scale as our primary focus. The climate records showed trends of warmer and drier conditions in the region. The annual daily mean, maximum and minimum temperature increased whereas the diurnal temperature range (DTR) decreased. The decreasing trend of annual precipitation was not significant. However, the vapor pressure deficit (VPD) increased significantly. On the decadal scale, the warming and drying trends were more significant in the last 30 years than the preceding 20 years. The climate change varied among biomes, with more pronounced changes in the grassland and the desert biomes than in the forest biome. DTR and VPD showed the clearest inter-biome gradient from the lowest rate of change in the forest biome to the highest rate of change in the desert biome. The rates of change also showed large variations among the individual stations. Our findings correspond with the IPCC predictions that the future climate will vary significantly by location and through time, suggesting that adaptation strategies also need to be spatially viable.

  10. Mid- to Late-Holocene pollen-based biome reconstructions for Colombia

    NARCIS (Netherlands)

    Marchant, R.; Behling, H.; Berrío, J.C.; Cleef, A.M.; Duivenvoorden, J.; Hooghiemstra, H.; Kuhry, P.; Melief, B.; Geel, van B.; Hammen, van der T.; Reenen, van T.; Wille, M.

    2001-01-01

    The assignment of Colombian pollen data to biomes allows the data to be synthesised at 10 `time windows' from the present-day to 6000 radiocarbon years before present (BP). The modern reconstructed biomes are compared to a map of modern potential vegetation to check the applicability of the method

  11. Identification of biomes affected by marginal expansion of agricultural land use induced by increased crop consumption

    DEFF Research Database (Denmark)

    Kløverpris, Jesper Hedal

    2009-01-01

    to characterise these areas. The present study ascribes so-called biomes (natural potential vegetation) to the areas affected by agricultural expansion in order to provide a basis for assessing the environmental impacts from land use in the life cycle impact assessment (LCIA). The methodology builds...... on agricultural statistics and maps of global agricultural areas and the global distribution of biomes. The application of the method is illustrated with four examples. The results indicate that agricultural expansion on land suited for crop cultivation (cultivable land) typically affects forest biomes...... or potential grassland/steppe, whereas expansion on land suited for grazing but not for crop cultivation (grazable land) typically occurs on potential shrubland or a few other biomes depending on the region. Some uncertainty applies to the results but it is concluded that it is feasible to identify biomes...

  12. Climate and litter quality differently modulate the effects of soil fauna on litter decomposition across biomes.

    Science.gov (United States)

    García-Palacios, Pablo; Maestre, Fernando T; Kattge, Jens; Wall, Diana H

    2013-08-01

    Climate and litter quality have been identified as major drivers of litter decomposition at large spatial scales. However, the role played by soil fauna remains largely unknown, despite its importance for litter fragmentation and microbial activity. We synthesised litterbag studies to quantify the effect sizes of soil fauna on litter decomposition rates at the global and biome scales, and to assess how climate, litter quality and soil fauna interact to determine such rates. Soil fauna consistently enhanced litter decomposition at both global and biome scales (average increment ~ 37%). [corrected]. However, climate and litter quality differently modulated the effects of soil fauna on decomposition rates between biomes, from climate-driven biomes to those where climate effects were mediated by changes in litter quality. Our results advocate for the inclusion of biome-specific soil fauna effects on litter decomposition as a mean to reduce the unexplained variation in large-scale decomposition models. © 2013 John Wiley & Sons Ltd/CNRS.

  13. Climate sensitivity of shrub growth across the tundra biome

    DEFF Research Database (Denmark)

    Myers-Smith, Isla H.; Elmendorf, Sarah C.; Beck, Pieter S.A.

    2015-01-01

    Rapid climate warming in the tundra biome has been linked to increasing shrub dominance1–4. Shrub expansion can modify climate by altering surface albedo, energy and water balance, and permafrost2,5–8, yet the drivers of shrub growth remain poorly understood. Dendroecological data consisting...... of multi-decadal time series of annual shrub growth provide an underused resource to explore climate–growth relationships. Here, we analyse circumpolar data from 37 Arctic and alpine sites in 9 countries, including 25 species, and 42,000 annual growth records from 1,821 individuals. Our analyses...... demonstrate that the sensitivity of shrub growth to climate was: (1) heterogeneous, with European sites showing greater summer temperature sensitivity than North American sites, and (2) higher at sites with greater soil moisture and for taller shrubs (for example, alders and willows) growing at their northern...

  14. Improved simulation of poorly drained forests using Biome-BGC.

    Science.gov (United States)

    Bond-Lamberty, Ben; Gower, Stith T; Ahl, Douglas E

    2007-05-01

    Forested wetlands and peatlands are important in boreal and terrestrial biogeochemical cycling, but most general-purpose forest process models are designed and parameterized for upland systems. We describe changes made to Biome-BGC, an ecophysiological process model, that improve its ability to simulate poorly drained forests. Model changes allowed for: (1) lateral water inflow from a surrounding watershed, and variable surface and subsurface drainage; (2) adverse effects of anoxic soil on decomposition and nutrient mineralization; (3) closure of leaf stomata in flooded soils; and (4) growth of nonvascular plants (i.e., bryophytes). Bryophytes were treated as ectohydric broadleaf evergreen plants with zero stomatal conductance, whose cuticular conductance to CO(2) was dependent on plant water content. Individual model changes were parameterized with published data, and ecosystem-level model performance was assessed by comparing simulated output to field data from the northern BOREAS site in Manitoba, Canada. The simulation of the poorly drained forest model exhibited reduced decomposition and vascular plant growth (-90%) compared with that of the well-drained forest model; the integrated bryophyte photosynthetic response accorded well with published data. Simulated net primary production, biomass and soil carbon accumulation broadly agreed with field measurements, although simulated net primary production was higher than observed data in well-drained stands. Simulated net primary production in the poorly drained forest was most sensitive to oxygen restriction on soil processes, and secondarily to stomatal closure in flooded conditions. The modified Biome-BGC remains unable to simulate true wetlands that are subject to prolonged flooding, because it does not track organic soil formation, water table changes, soil redox potential or anaerobic processes.

  15. Two New Species and New Occurrences of Syneches Walker for Brazilian Biome of Caatinga (Diptera: Hybotidae: Hybotinae).

    Science.gov (United States)

    Soares, M M M; Ale-Rocha, R

    2018-03-13

    Syneches from Brazilian biome of Caatinga were studied, two new species are described, Syneches atratus sp. nov. and Syneches limeirai sp. nov., and three species, Syneches annulipes Bezzi, 1909, Syneches moraballi Smith, 1963, and Syneches rafaeli Ale-Rocha & Vieira, 2008, are recorded for the biome. An identification key for the species of Syneches from Caatinga biome is provided.

  16. Demographic trends and biological status of historic populations from Central Poland: the Ostrów Lednicki microregion.

    Science.gov (United States)

    Budnik, Alicja; Liczbińska, Grazyna; Gumna, Izabela

    2004-12-01

    The microregion of Ostrów Lednicki in the province of Wielkopolska was the center of the formation of the Polish State in Early Middle Ages. The analysis of skeletal remains and parish records from the region documented the biological status of inhabitants and its changes over a millennium. The study material comprised 424 human skeletons from an Early Medieval burial ground on Lake Lednica, records of 2,704 deaths from the registers of the Roman Catholic parish of Dziekanowice, made between 1818-1903, data on the deaths of 929,192 inhabitants of rural areas all over the province Wielkopolska obtained from Prussian statistical materials for the years 1865-1900, and comparative data from the literature. Assuming both a stationary population model and a stable population model with nonzero natural increase, parameters of life tables and measures of opportunity for natural selection (Crow's index I(m), potential gross reproductive rate R(pot), and the biological state index I(bs)) were calculated for the Early Middle Ages and for the two periods of the 19th century which were characterized by different laws of land ownership and thus different rural economies. In the first period, peasants were tenants, whereas in the second, they were given freehold of the land they cultivated. Causes of death were also analyzed. A distinct increase in longevity from the early Middle Ages to the end of the 19th and the beginning of the 20th century was found. This was related to a higher level of demographic development in the parish of Dziekanowice during the 19th century, which was achieved earlier than in other areas of Poland. This was confirmed by genetic measures: coefficients of exogamy and coefficients of kinship. The reasons were related to the historical prominence of this region and to its proximity to the first two capitals of the Polish state, Gniezno and Poznań. 2004 Wiley-Liss, Inc.

  17. Global pressures, specific responses: effects of nutrient enrichment in streams from different biomes

    International Nuclear Information System (INIS)

    Artigas, Joan; García-Berthou, Emili; Gómez, Nora; Romaní, Anna M; Sabater, Sergi; Bauer, Delia E; Cochero, Joaquín; Cortelezzi, Agustina; Rodrigues-Capítulo, Alberto; Castro, Maria I; Donato, John C; Colautti, Darío C; Elosegi, Arturo; Feijoó, Claudia; Giorgi, Adonis; Leggieri, Leonardo; Muñoz, Isabel

    2013-01-01

    We assessed the effects of nutrient enrichment on three stream ecosystems running through distinct biomes (Mediterranean, Pampean and Andean). We increased the concentrations of N and P in the stream water 1.6–4-fold following a before–after control–impact paired series (BACIPS) design in each stream, and evaluated changes in the biomass of bacteria, primary producers, invertebrates and fish in the enriched (E) versus control (C) reaches after nutrient addition through a predictive-BACIPS approach. The treatment produced variable biomass responses (2–77% of explained variance) among biological communities and streams. The greatest biomass response was observed for algae in the Andean stream (77% of the variance), although fish also showed important biomass responses (about 9–48%). The strongest biomass response to enrichment (77% in all biological compartments) was found in the Andean stream. The magnitude and seasonality of biomass responses to enrichment were highly site specific, often depending on the basal nutrient concentration and on windows of ecological opportunity (periods when environmental constraints other than nutrients do not limit biomass growth). The Pampean stream, with high basal nutrient concentrations, showed a weak response to enrichment (except for invertebrates), whereas the greater responses of Andean stream communities were presumably favored by wider windows of ecological opportunity in comparison to those from the Mediterranean stream. Despite variation among sites, enrichment globally stimulated the algal-based food webs (algae and invertebrate grazers) but not the detritus-based food webs (bacteria and invertebrate shredders). This study shows that nutrient enrichment tends to globally enhance the biomass of stream biological assemblages, but that its magnitude and extent within the food web are complex and are strongly determined by environmental factors and ecosystem structure. (letter)

  18. Distribution and biology of the Blackmouth catshark Galeus melastomus in the Strait of Sicily (Central Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. RAGONESE

    2009-05-01

    Full Text Available The Blackmouth catshark, Galeus melastomus, Rafinesque, 1810 (Carcharhiniformes; Scyliorhinidae, is a common, although at present discarded, by- catch of the bottom trawl fisheries in the Strait of Sicily. Given its ecological interest, data gathered in experimental bottom trawl surveys were analysed in order to describe its distribution and main biological traits. The Blackmouth catshark was sampled almost exclusively on the upper slope (200-800, showing the highest frequency of occurrence (69-100%, biomass (BI; 10-85 kg*km-2 and density (DI; 54-506 N*km-2 indexes in the deeper (501-800m grounds. Individual size (total length, TL, mm were between 70-590 and 90-510 in females and males, respectively. The sex ratio (SR was around 0.5. The SR by size showed a gradual decrease till 450 mm class size, followed by an increase up 1 after 500 mm. Virginal/immature specimens represented the bulk of the samples in both females (77% and males (65%; the length at 50% of sexual maturity (Lm50% and corresponding maturity range (Lm25% - Lm75% was 433 (423-443 and 380 (366-394 mm, respectively.

  19. An initial biochemical and cell biological characterization of the mammalian homologue of a central plant developmental switch, COP1

    Directory of Open Access Journals (Sweden)

    Wang Haiyang

    2002-12-01

    Full Text Available Abstract Background Constitutive photomorphogenic 1 (COP1 has been defined as a central regulator of photomorphogenic development in plants, which targets key transcription factors for proteasome-dependent degradation. Although COP1 mammalian homologue has been previously reported, its function and distribution in animal kingdom are not known. Results Here we report the characterization of full-length human and mouse COP1 cDNAs and the genomic structures of the COP1 genes from several different species. Mammalian COP1 protein binds to ubiquitinated proteins in vivo and is itself ubiquitinated. Furthermore, mammalian COP1 is predominately nuclear localized and exists primarily as a complex of over 700 kDa. Through mutagenesis studies, we have defined a leucine-rich nuclear export signal (NES within the coiled-coil domain of mammalian COP1 and a nuclear localization signal (NLS, which is composed of two clusters of positive-charged amino acids, bridged by the RING finger. Disruption of the RING finger structure abolishes the nuclear import, while deletion of the entire RING finger restores the nuclear import. Conclusions Our data suggest that mammalian COP1, similar to its plant homologue, may play a role in ubiquitination. Mammalian COP1 contains a classic leucine-rich NES and a novel bipartite NLS bridged by a RING finger domain. We propose a working model in which the COP1 RING finger functions as a structural scaffold to bring two clusters of positive-charged residues within spatial proximity to mimic a bipartite NLS. Therefore, in addition to its well-characterized role in ubiquitination, the RING finger domain may also play a structural role in nuclear import.

  20. Ornamental Eudicotyledons from grasslands of Pampa biome in Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Ana De Araújo Carrion

    2012-10-01

    Full Text Available The present study aims at investigating the group of Eudicotyledons native plants with ornamental potential of grasslands from the Pampa biome in the south of Brazil. The Pampa presents a high level of biodiversity; however, it requires studies related to the richness of vascular plants and its biological and ecological knowledge. The purpose of this work is to elaborate a preliminary inventory of this group of plants, analyzing the ornamental potential of each specie and indicating those that could be considered as being priorities for the purpose of sustainable use with this objective. Some grassland species were selected through the search for information in herbarium registers, national and international works about decorative plants, floristic surveys, besides the authors´ practical knowledge. Some parameters and values were associated, aiming at reducing the subjectivity of the choice. The survey resulted in a list of 177 species distributed in 36 families and 101 genera. Among these species, ten presented high ornamental potential. These data show that the richness of the grassland native ornamental flora is high, even though its use is poorly known. The use of these plants, if in a sustainable manner, can produce economic and ecological benefits.

  1. Methane Production and Transport within the Marsh Biome of Biosphere 2

    Science.gov (United States)

    Molnar, Jennifer; Goodridge, Kelven

    1997-01-01

    In recent decades, the concentration of methane in the earth's atmosphere increased 1-2% annually. It's rate of increases, combined with methane's effectiveness as a greenhouse gas, has led to an intensive research effort to determine the sources and sinks of the gas in the environment. Biosphere 2 offers a unique opportunity to contribute to the effort because it lacks a major photochemical sink present in the Earth's atmosphere. Researchers can therefore concentrate on biological processes involved in methane cycles. Wetlands are a large source of atmospheric methane, due to anoxic conditions in the sediments and the abundance of organic materials. In order to determine if these conditions in Biosphere 2 also promote methane production, this study looked for the fluxes of methane and methods of transport of the gas from from the water and sediments to the atmosphere in the Marsh Biome. Fluxes of methane from the sediments and waters were measured using static chambers, peepers, and leaf bags. Fluxes and vertical profiles of methane in the sediments show that substantial amounts of methane are being produced in the marsh and are being transported into the Biosphere 2 environment.

  2. Findings from NSABP Protocol No. B-04: comparison of radical mastectomy with alternative treatments. II. The clinical and biologic significance of medial-central breast cancers

    International Nuclear Information System (INIS)

    Fisher, B.; Wolmark, N.; Redmond, C.; Deutsch, M.; Fisher, E.R.

    1981-01-01

    Findings from 1665 women with primary breast cancer, treated at 34 NSABP institutions in Canada and the United States, have failed to demonstrate that patients with medial-central tumors had a greater probability of developing distant metastases or dying than did those with lateral tumors despite the greater incidence of internal mammary (IM) node involvement when tumors are medial-central in location. A comparison of patients with similar clinical nodal status and tumor location who were treated either by radical mastectomy (RM) or by total mastectomy plus radiation therapy (TM + RT) failed to indicate that radiation of IM nodes reduced the probability of distant treatment failure (TF) or mortality. When findings from patients having equivalent clinical nodal status and tumor location treated by TM alone or TM + RT were compared, it was found that the addition of RT failed to alter the probability of the occurrence of a distant TF or of death. This was despite the fact that in the nonradiated group two putative sources of further tumor spread, i.e., positive axillary and IM nodes, were left unremoved and untreated. The findings provide further insight into the biologic significance of the positive lymph node and confirm our prior contention that positive regional lymph nodes are indicators of a host-tumor relationship which permits the development of metastases and that they are not important investigators of distant disease

  3. La filatelia biomédica Biomedicine philately

    Directory of Open Access Journals (Sweden)

    Emilio J.A. Roldán

    2011-02-01

    Full Text Available La temática biomédica es un capítulo extendido de la filatelia o coleccionismo de sellos postales. Inaugura la temática la imagen de la diosa Hygeia, en un sello de la isla Nevis de 1861. Los primeros médicos retratados en una estampilla son tres constitucionalistas americanos, en un ejemplar de 1869, pero recién en 1937 aparecen médicos holandeses en reconocimiento específico de sus aportes a la salud. En la Argentina la primera estampilla que oficialmente se ocupa del tema es de 1944, en ayuda de las víctimas del terremoto de San Juan. Florentino Ameghino es el primer científico incluido en 1954, y en 1967 se edita un sello conmemorativo de la Dra. Cecilia Grierson. La filatelia argentina luego reconoce varios de nuestros científicos y médicos, congresos, universidades, campañas sanitarias, temas de odontología, farmacia, enfermería y otros, generando un amplio material filatélico en reconocimiento del valor social que la ciencia biomédica argentina ha logrado en el contexto propio e internacional. Posiblemente sea un científico, el Dr. Bernardo Houssay, uno de los argentinos más veces editado en distintos sellos postales de la filatelia mundial.Biomedicine is a vast field in philately or stamp collecting. It opens the topic the image of the goddess Hygeia, issued in a stamp from Nevis Island dated 1861. The first physicians to appear printed in stamps, in 1869, were three American constitutionalists, but only in 1937 there appear Dutch physicians as an acknowledgement of their contribution to public health. In Argentina the first stamp officially related to the topic was issued in 1944, to raise funds for the victims of the San Juan earthquake. Florentino Ameghino was the first scientist included in 1954, and in 1967 a stamp was issued in honour of Dr. Cecilia Grierson. Afterwards, Argentinean philately has recognized several of our scientists and physicians, congresses, universities, health campaigns, dentistry topics

  4. The Biology of the Triatomine Bugs Native to South Central Texas and Assessment of the Risk They Pose for Autochthonous Chagas Disease Exposure.

    Science.gov (United States)

    Wozniak, Edward J; Lawrence, Gena; Gorchakov, Rodion; Alamgir, Hasanat; Dotson, Ellen; Sissel, Blake; Sarkar, Sahotra; Murray, Kristy O

    2015-10-01

    Triatomine bugs are a group of hematophagous arthropods that can serve as biological vectors for Trypanosoma cruzi , the etiological agent of American trypanosomiasis (Chagas disease). Because of differences in the biology and feeding habits among triatomine species, some are more likely than others to be involved in zoonotic and/or human-to-human transmission cycles of T. cruzi . In an attempt to assess the risk for Chagas disease exposure in south-central Texas, human habitations across Texas Health Service Region 8 (HSR 8) and surrounding counties were surveyed for triatomines to characterize the geographic distribution, species-specific biology, and T. cruzi -infection prevalence better. Between May 2010 and August 2013, a total of 545 triatomines representing all 5 known indigenous species (Triatoma gerstaeckeri, Triatoma indictiva, Triatoma lecticularia, Triatoma sanguisuga, and Triatoma protracta woodi) were collected from 59 sites across the region. Triatoma gerstaeckeri was the species most commonly found in domestic and peridomestic ecotopes across Texas HSR 8, representing over 80% of the triatomines collected. Adult T. gerstaeckeri exhibited a seasonal dispersal pattern that began in late April, peaked in mid-May, and then continued into August. On homes with available crevices in the exterior walls, adult T. gerstaeckeri were observed emerging from or entering these protective microhabitats, suggesting possible opportunistic colonization of some exterior walls compartments. Laboratory testing of triatomine hindgut contents for T. cruzi by PCR demonstrated the adult T. gerstaeckeri-infection prevalence across Texas HSR 8 to be 64%. Monitoring peridomestic adult T. gerstaeckeri over the seasonal dispersal peak demonstrated statistically significant increases in both their T. cruzi -infection prevalence (P < 0.01) and tendency to invade human dwellings (P < 0.01) in the later aspect of the emergence peak. In addition to the adult insects, variably sized

  5. Simulating economics and environmental impacts of beef and soybean systems in Brazil's Pamas and Amozon Biomes

    Science.gov (United States)

    Recent reductions in the deforestation of the Amazon biome have highlighted the need for the sustainable intensification of beef and commodity crop production in Brazil to increase agricultural productivity without accelerating adverse environmental impacts related to greenhouse gas emissions, eutro...

  6. Biome-BGC: Modeling Effects of Disturbance and Climate (Thornton et al. 2002)

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This archived model product contains the directions, executables, and procedures for running Biome-BGC, Version 4.1.1, to recreate the results of the...

  7. BIOME: A scientific data archive search-and-order system using browser-aware, dynamic pages

    Science.gov (United States)

    Jennings, S. V.; Yow, T. G.; Ng, V. W.

    1997-01-01

    The Oak Ridge National Laboratory's (ORNL) Distributed Active Archive Center (DAAC) is a data archive and distribution center for the National Air and Space Administration's (NASA) Earth Observing System Data and Information System (EOSDIS). Both the Earth Observing System (EOS) and EOSDIS are components of NASA's contribution to the US Global Change Research Program through its Mission to Planet Earth Program. The ORNL DAAC provides access to data used in ecological and environmental research such as global change, global warming, and terrestrial ecology. Because of its large and diverse data holdings, the challenge for the ORNL DAAC is to help users find data of interest from the hundreds of thousands of files available at the DAAC without overwhelming them. Therefore, the ORNL DAAC has developed the Biogeochemical Information Ordering Management Environment (BIOME), a customized search and order system for the World Wide Web (WWW). BIOME is a public system located at http://www-eosdis. ornl.gov/BIOME/biome.html.

  8. Biome-BGC: Modeling Carbon Dynamics in Ponderosa Pine Stands (Law et al. 2003)

    Data.gov (United States)

    National Aeronautics and Space Administration — This archived model product contains the directions, executables, and procedures for running Biome-BGC, Version 4.1.2, to recreate the results of the following...

  9. Biome-BGC: Terrestrial Ecosystem Process Model, Version 4.1.1

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Biome-BGC is a computer program that estimates fluxes and storage of energy, water, carbon, and nitrogen for the vegetation and soil components of...

  10. Biome-BGC: Terrestrial Ecosystem Process Model, Version 4.1.1

    Data.gov (United States)

    National Aeronautics and Space Administration — Biome-BGC is a computer program that estimates fluxes and storage of energy, water, carbon, and nitrogen for the vegetation and soil components of terrestrial...

  11. Climate control of terrestrial carbon exchange across biomes and continents

    Energy Technology Data Exchange (ETDEWEB)

    Yi Chuixiang; Wolbeck, John; Xu Xiyan [School of Earth and Environmental Sciences, Queens College, City University of New York, NY 11367 (United States); Ricciuto, Daniel [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Li Runze [Department of Statistics, Pennsylvania State University, University Park, PA 16802 (United States); Nilsson, Mats [Department of Forest Ecology, Swedish University of Agricultural Sciences, SE-901 83 Umeaa (Sweden); Aires, Luis [CESAM and Department of Environmental Engineering, School of Technology and Management, Polytechnic Institute of Leiria (Portugal); Albertson, John D [Department of Civil and Environmental Engineering, Duke University, Durham, NC 22708-0287 (United States); Ammann, Christof [Federal Research Station Agroscope Reckenholz-Taenikon, Reckenholzstrasse 191, 8046 Zuerich (Switzerland); Arain, M Altaf [School of Geography and Earth Sciences, McMaster University, Hamilton, ON, L8S 4K1 (Canada); De Araujo, Alessandro C [Instituto Nacional de Pesquisas da Amazonia, Programa LBA, Campus-II, Manaus-Amazonas 69060 (Brazil); Aubinet, Marc [University of Liege, Gembloux Agro-Bio Tech, Unit of Biosystem Physics, 2 Passage des Deportes, 5030 Gembloux (Belgium); Aurela, Mika [Finnish Meteorological Institute, Climate Change Research, FI-00101 Helsinki (Finland); Barcza, Zoltan [Department of Meteorology, Eoetvoes Lorand University, H-1117 Budapest, Pazmany setany 1/A (Hungary); Barr, Alan [Climate Research Division, Environment Canada, Saskatoon, SK, S7N 3H5 (Canada); Berbigier, Paul [INRA, UR1263 EPHYSE, Villenave d' Ornon F-33883 (France); Beringer, Jason [School of Geography and Environmental Science, Monash University, Clayton, Victoria 3800 (Australia); Bernhofer, Christian [Institute of Hydrology and Meteorology, Dresden University of Technology, Pienner Strasse 23, D-01737, Tharandt (Germany)

    2010-07-15

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate-carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO{sub 2} exchange with the atmosphere across biomes and continents are lacking. Here we present data describing the relationships between net ecosystem exchange of carbon (NEE) and climate factors as measured using the eddy covariance method at 125 unique sites in various ecosystems over six continents with a total of 559 site-years. We find that NEE observed at eddy covariance sites is (1) a strong function of mean annual temperature at mid- and high-latitudes, (2) a strong function of dryness at mid- and low-latitudes, and (3) a function of both temperature and dryness around the mid-latitudinal belt (45 deg. N). The sensitivity of NEE to mean annual temperature breaks down at {approx} 16 deg. C (a threshold value of mean annual temperature), above which no further increase of CO{sub 2} uptake with temperature was observed and dryness influence overrules temperature influence.

  12. Climate control of terrestrial carbon exchange across biomes and continents

    International Nuclear Information System (INIS)

    Yi Chuixiang; Wolbeck, John; Xu Xiyan; Ricciuto, Daniel; Li Runze; Nilsson, Mats; Aires, Luis; Albertson, John D; Ammann, Christof; Arain, M Altaf; De Araujo, Alessandro C; Aubinet, Marc; Aurela, Mika; Barcza, Zoltan; Barr, Alan; Berbigier, Paul; Beringer, Jason; Bernhofer, Christian

    2010-01-01

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate-carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO 2 exchange with the atmosphere across biomes and continents are lacking. Here we present data describing the relationships between net ecosystem exchange of carbon (NEE) and climate factors as measured using the eddy covariance method at 125 unique sites in various ecosystems over six continents with a total of 559 site-years. We find that NEE observed at eddy covariance sites is (1) a strong function of mean annual temperature at mid- and high-latitudes, (2) a strong function of dryness at mid- and low-latitudes, and (3) a function of both temperature and dryness around the mid-latitudinal belt (45 deg. N). The sensitivity of NEE to mean annual temperature breaks down at ∼ 16 deg. C (a threshold value of mean annual temperature), above which no further increase of CO 2 uptake with temperature was observed and dryness influence overrules temperature influence.

  13. Diversity of medium and large sized mammals in a Cerrado fragment of central Brazil

    Directory of Open Access Journals (Sweden)

    F.S. Campos

    2013-11-01

    Full Text Available Studies related to community ecology of medium and large mammals represent a priority in developing strategies for conservation of their habitats. Due to the significant ecological importance of these species, a concern in relation to anthropogenic pressures arises since their populations are vulnerable to hunting and fragmentation. In this study, we aimed to analyze the diversity of medium and large mammals in a representative area of the Cerrado biome, located in the National Forest of Silvânia, central Brazil, providing insights for future studies on the biodiversity and conservation of Cerrado mammals. Sampling was carried out by linear transects, search for traces, footprint traps and camera traps. We recorded 23 species, among which three are listed in threat categories (e.g., Myrmecophaga tridactyla, Chrysocyon brachyurus and Leopardus tigrinus. We registered 160 records in the study area, where the most frequently recorded species were Didelphis albiventris (30 records and Cerdocyon thous (28 records. Our results indicated that a small protected area of Cerrado can include a large and important percentage of the diversity of mammals in this biome, providing information about richness, abundance, spatial distribution and insights for future studies on the biodiversity and conservation of these biological communities.

  14. Terrestrial Macrofungal Diversity from the Tropical Dry Evergreen Biome of Southern India and Its Potential Role in Aerobiology.

    Science.gov (United States)

    Priyamvada, Hema; Akila, M; Singh, Raj Kamal; Ravikrishna, R; Verma, R S; Philip, Ligy; Marathe, R R; Sahu, L K; Sudheer, K P; Gunthe, S S

    2017-01-01

    Macrofungi have long been investigated for various scientific purposes including their food and medicinal characteristics. Their role in aerobiology as a fraction of the primary biological aerosol particles (PBAPs), however, has been poorly studied. In this study, we present a source of macrofungi with two different but interdependent objectives: (i) to characterize the macrofungi from a tropical dry evergreen biome in southern India using advanced molecular techniques to enrich the database from this region, and (ii) to assess whether identified species of macrofungi are a potential source of atmospheric PBAPs. From the DNA analysis, we report the diversity of the terrestrial macrofungi from a tropical dry evergreen biome robustly supported by the statistical analyses for diversity conclusions. A total of 113 macrofungal species belonging to 54 genera and 23 families were recorded, with Basidiomycota and Ascomycota constituting 96% and 4% of the species, respectively. The highest species richness was found in the family Agaricaceae (25.3%) followed by Polyporaceae (15.3%) and Marasmiaceae (10.8%). The difference in the distribution of commonly observed macrofungal families over this location was compared with other locations in India (Karnataka, Kerala, Maharashtra, and West Bengal) using two statistical tests. The distributions of the terrestrial macrofungi were distinctly different in each ecosystem. We further attempted to demonstrate the potential role of terrestrial macrofungi as a source of PBAPs in ambient air. In our opinion, the findings from this ecosystem of India will enhance our understanding of the distribution, diversity, ecology, and biological prospects of terrestrial macrofungi as well as their potential to contribute to airborne fungal aerosols.

  15. Mathematical biology

    CERN Document Server

    Murray, James D

    1993-01-01

    The book is a textbook (with many exercises) giving an in-depth account of the practical use of mathematical modelling in the biomedical sciences. The mathematical level required is generally not high and the emphasis is on what is required to solve the real biological problem. The subject matter is drawn, e.g. from population biology, reaction kinetics, biological oscillators and switches, Belousov-Zhabotinskii reaction, reaction-diffusion theory, biological wave phenomena, central pattern generators, neural models, spread of epidemics, mechanochemical theory of biological pattern formation and importance in evolution. Most of the models are based on real biological problems and the predictions and explanations offered as a direct result of mathematical analysis of the models are important aspects of the book. The aim is to provide a thorough training in practical mathematical biology and to show how exciting and novel mathematical challenges arise from a genuine interdisciplinary involvement with the biosci...

  16. The phylogeny and biogeography of Hakea (Proteaceae) reveals the role of biome shifts in a continental plant radiation.

    Science.gov (United States)

    Cardillo, Marcel; Weston, Peter H; Reynolds, Zoe K M; Olde, Peter M; Mast, Austin R; Lemmon, Emily M; Lemmon, Alan R; Bromham, Lindell

    2017-08-01

    The frequency of evolutionary biome shifts during diversification has important implications for our ability to explain geographic patterns of plant diversity. Recent studies present several examples of biome shifts, but whether frequencies of biome shifts closely reflect geographic proximity or environmental similarity of biomes remains poorly known. We explore this question by using phylogenomic methods to estimate the phylogeny of Hakea, a diverse Australian genus occupying a wide range of biomes. Model-based estimation of ancestral regions indicates that Hakea began diversifying in the Mediterranean biome of southern Australia in the Middle Eocene-Early Oligocene, and dispersed repeatedly into other biomes across the continent. We infer around 47 shifts between biomes. Frequencies of shifts between pairs of biomes are usually similar to those expected from their geographic connectedness or climatic similarity, but in some cases are substantially higher or lower than expected, perhaps reflecting how readily key physiological traits can be modified to adapt lineages to new environments. The history of frequent biome-shifting is reflected in the structure of present-day assemblages, which tend to be more phylogenetically diverse than null-model expectations. The case of Hakea demonstrates that the radiation of large plant clades across wide geographic areas need not be constrained by dispersal limitation or conserved adaptations to particular environments. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  17. USING LUDIC ACTIVITIES TO EXPLAIN THE BIOME CONCEPT

    Directory of Open Access Journals (Sweden)

    Aline Riccioni de Melos

    2015-12-01

    Full Text Available This paper contributes to research on the role of ludic activities in teaching and learning physical geography content during the last four years of primary school. We question the discourse that identifies students’ lack of interest as the obstacle to teaching physical geography. This study contributes by questioning this obstacle. We note that few studies exist on this topic, according to the CAPES (Coordination for higher Education Staff Development dissertation database, in 2011 only five were completed. The theoretical basis for the study considers work by Graciolli (2009, Silva et al. (2010, Rupel (2011 and Freitas and Salvi (2011, authors who defend the use of ludic activities in teaching methodology. In 2010, the “Biome Game” for 6th year students was developed based on this theoretical framework as part of the required course “Supervised Practice”. The goal of the activity was to think about how the concept of biome was created, and the methodology used valued recreational approaches. The empirical results of this experiment, which involved developing and implementing the game during the Supervised Practice course, demonstrate the importance of ludic pedagogical strategies for teaching physical geography in Brazilian primary education. O presente artigo traz contribuições de pesquisa sobre a função da ludicidade no ensino-aprendizagem de conteúdos da geografia física, no segundo segmento do ensino fundamental. Tal questão problematiza o discurso sobre o desinteresse dos alunos, como significativo obstáculo para a didática da geografia física. A pertinência do presente estudo está em reconhecer esta questão, tendo em vista que existem poucos estudos na área, totalizando em 2011, segundo o banco de dissertações da CAPES, somente cinco trabalhos concluídos. Nossa investigação dialoga com Graciolli (2009, Silva et al. (2010, Rupel (2011 e Freitas e Salvi (2011, autores dedicados à defesa da utilização de

  18. Documentation of meteorological data from the coniferous forest biome primary station in Oregon.

    Science.gov (United States)

    R.H. Waring; H.R. Holbo; R.P. Bueb; R.L. Fredriksen

    1978-01-01

    As part of the International Biological Program, a primary meteorological station was installed in the west-central Cascade Range of Oregon. Short-wave solar radiation, air temperature, dewpoint temperature, windspeed, and precipitation are recorded continuously. Climatic data are summarized in a daily record available from May 11, 1972, to date. This report details...

  19. Does a General Temperature-Dependent Q10 Model of Soil Respiration Exist at Biome and Global Scale?

    Institute of Scientific and Technical Information of China (English)

    Hua CHEN; Han-Qin TIAN

    2005-01-01

    Soil respiration (SR) is commonly modeled by a Q10 (an indicator of temperature sensitivity)function in ecosystem models. Q10is usually treated as a constant of 2 in these models, although Q10 value of SR often decreases with increasing temperatures. It remains unclear whether a general temperaturedependent Q10 model of SR exists at biome and global scale. In this paper, we have compiled the long-term Q10 data of 38 SR studies ranging from the Boreal, Temperate, to Tropical/Subtropical biome on four continents.Our analysis indicated that the general temperature-dependent biome Q10 models of SR existed, especially in the Boreal and Temperate biomes. A single-exponential model was better than a simple linear model in fitting the average Q10 values at the biome scale. Average soil temperature is a better predictor of Q10 value than average air temperature in these models, especially in the Boreal biome. Soil temperature alone could explain about 50% of the Q10 variations in both the Boreal and Temperate biome single-exponential Q10 model. Q10 value of SR decreased with increasing soil temperature but at quite different rates among the three biome Q10 models. The k values (Q10 decay rate constants) were 0.09, 0.07, and 0.02/℃ in the Boreal, Temperate, and Tropical/Subtropical biome, respectively, suggesting that Q10 value is the most sensitive to soil temperature change in the Boreal biome, the second in the Temperate biome, and the least sensitive in the Tropical/Subtropical biome. This also indirectly confirms that acclimation of SR in many soil warming experiments probably occurs. The k value in the "global" single-exponential Q10 model which combined both the Boreal and Temperate biome data set was 0.08/℃. However, the global general temperature-dependent Q10model developed using the data sets of the three biomes is not adequate for predicting Q10 values of SR globally.The existence of the general temperature-dependent Q10 models of SR in the Boreal and

  20. Micro to the Macro Biome Can Biology Affect the Big Picture Through Small Changes?

    Science.gov (United States)

    Morin, Lee

    2014-01-01

    Life has had a profound impact on the geological history of our planet, which in turn has had a profound impact back on the evolution of life. Life has been able to adapt and spread into every planetary nook and cranny. At this point in history, life is becoming able to engineer itself, with extreme consequences we are only dimly able to foresee. One probable outcome will be the facilitation of the expansion of the range of life to beyond our planetary cradle, an evolutionary step as profound as the ancient transition from sea to land. Current efforts at NASA and aboard the International Space Station will be discussed in this context.

  1. Micro to the Macro Biome: Can Biology Affect the Big Picture Through Small Changes?

    Science.gov (United States)

    Morin, Lee

    2014-01-01

    Life has had a profound impact on the geological history of our planet, which in turn has had a profound impact back on the evolution of life. Life has been able to adapt and spread into every planetary nook and cranny. At this point in history, life is becoming able to engineer itself, with extreme consequences we are only dimly able to foresee. One probable outcome will be the facilitation of the expansion of the range of life to beyond our planetary cradle, an evolutionary step as profound as the ancient transition from sea to land. Current efforts at NASA and aboard the International Space Station will be discussed in this context.

  2. Biology of the repair of central nervous system demyelinated lesions: an appraisal Biologia da reparação de lesões desmielinizantes do sistema nervoso central: uma avaliação

    Directory of Open Access Journals (Sweden)

    L. A. V Peireira

    1996-06-01

    Full Text Available The integrity of myelin sheaths is maintained by oligodendrocytes and Schwann cells respectively in the central nervous system (CNS and in the peripheral nervous system. The process of demyelination consisting of the withdrawal of myelin sheaths from their axons is a characteristic feature of multiple sclerosis, the most common human demyelinating disease. Many experimental models have been designed to study the biology of demyelination and remyelination (repair of the lost myelin in the CNS, due to the difficulties in studying human material. In the ethidium bromide (an intercalating gliotoxic drug model of demyelination, CNS remyelination may be carried out by surviving oligodendrocytes and/or by cells differentiated from the primitive cell lines or either by Schwann cells that invade the CNS. However, some factors such as the age of the experimental animals, intensity and time of exposure to the intercalating chemical and the topography of the lesions have marked influence on the repair of the tissue.A integridade da bainha de mielina é fornecida pelos oligodendrócitos e pelas células de Schwann, no sistema nervoso central (SNC e no sistema nervoso periférico, respectivamente. O fenômeno de desmielinização refere-se à remoção das bainhas de mielina de axônios e este fato é característico na esclerose múltipla, a doença desmielinizante do SNC mais comum no homem. Muitos modelos experimentais têm sido utilizados para o estudo da biologia da desmielinização e remielinização no SNC, face à dificuldade de estudo de material humano. No modelo experimental da droga intercalate, gliotóxica, brometo de etídio, a remielinização do SNC pode ser efetuada por oligodendrócitos sobreviventes à lesão e/ou oriundos de diferenciação de linhagens celulares mais primitivas e por células de Schwann que invadem o SNC. No entanto, fatores como a idade dos animais, a intensidade, e o tempo de exposição ao agente intercalante e a

  3. Inferring biome-scale net primary productivity from tree-ring isotopes

    Science.gov (United States)

    Pederson, N.; Levesque, M.; Williams, A. P.; Hobi, M. L.; Smith, W. K.; Andreu-Hayles, L.

    2017-12-01

    Satellite estimates of vegetation growth (net primary productivity; NPP), tree-ring records, and forest inventories indicate that ongoing climate change and rising atmospheric CO2 concentration are altering productivity and carbon storage of forests worldwide. The impact of global change on the trends of NPP, however, remain unknown because of the lack of long-term high-resolution NPP data. For the first time, we tested if annually resolved carbon (δ13C) and oxygen (δ18O) stable isotopes from the cellulose of tree rings from trees in temperate regions could be used as a tool for inferring NPP across spatiotemporal scales. We compared satellite NPP estimates from the moderate-resolution imaging spectroradiometer sensor (MODIS, product MOD17A) and a newly developed global NPP dataset derived from the Global Inventory Modeling and Mapping Studies (GIMMS) dataset to annually resolved tree-ring width and δ13C and δ18O records from four sites along a hydroclimatic gradient in Eastern and Central United States. We found strong correlations across large geographical regions between satellite-derived NPP and tree-ring isotopes that ranged from -0.40 to -0.91. Notably, tree-ring derived δ18O had the strongest relation to climate. The results were consistent among the studied tree species (Quercus rubra and Liriodendron tulipifera) and along the hydroclimatic conditions of our network. Our study indicates that tree-ring isotopes can potentially be used to reconstruct NPP in time and space. As such, our findings represent an important breakthrough for estimating long-term changes in vegetation productivity at the biome scale.

  4. Abiotic and biotic determinants of leaf carbon exchange capacity from tropical to high boreal biomes

    Science.gov (United States)

    Smith, N. G.; Dukes, J. S.

    2016-12-01

    Photosynthesis and respiration on land represent the two largest fluxes of carbon dioxide between the atmosphere and the Earth's surface. As such, the Earth System Models that are used to project climate change are high sensitive to these processes. Studies have found that much of this uncertainty is due to the formulation and parameterization of plant photosynthetic and respiratory capacity. Here, we quantified the abiotic and biotic factors that determine photosynthetic and respiratory capacity at large spatial scales. Specifically, we measured the maximum rate of Rubisco carboxylation (Vcmax), the maximum rate of Ribulose-1,5-bisphosphate regeneration (Jmax), and leaf dark respiration (Rd) in >600 individuals of 98 plant species from the tropical to high boreal biomes of Northern and Central America. We also measured a bevy of covariates including plant functional type, leaf nitrogen content, short- and long-term climate, leaf water potential, plant size, and leaf mass per area. We found that plant functional type and leaf nitrogen content were the primary determinants of Vcmax, Jmax, and Rd. Mean annual temperature and mean annual precipitation were not significant predictors of these rates. However, short-term climatic variables, specifically soil moisture and air temperature over the previous 25 days, were significant predictors and indicated that heat and soil moisture deficits combine to reduce photosynthetic capacity and increase respiratory capacity. Finally, these data were used as a model benchmarking tool for the Community Land Model version 4.5 (CLM 4.5). The benchmarking analyses determined errors in the leaf nitrogen allocation scheme of CLM 4.5. Under high leaf nitrogen levels within a plant type the model overestimated Vcmax and Jmax. This result suggested that plants were altering their nitrogen allocation patterns when leaf nitrogen levels were high, an effect that was not being captured by the model. These data, taken with models in mind

  5. Carbon emission as a function of energy generation in hydroelectric reservoirs in Brazilian dry tropical biome

    International Nuclear Information System (INIS)

    Ometto, Jean P.; Cimbleris, André C.P.; Santos, Marco A. dos; Rosa, Luiz P.; Abe, Donato; Tundisi, José G.; Stech, José L.; Barros, Nathan; Roland, Fábio

    2013-01-01

    Most energy generation globally is fueled by coal and oil, raising concerns about greenhouse gas emissions. Hydroelectric reservoirs are anthropogenic aquatic systems that occur across a wide geographical extent, and, in addition to their importance for energy production, they have the potential to release two important greenhouse gases (GHGs), carbon dioxide and methane. We report results from an extensive study of eight hydroelectric reservoirs located in central and southeastern tropical Brazil. In the Brazilian dry tropical biome reservoirs, emissions (in tons of CO 2 Eq. per MW h) varied from 0.01 to 0.55, and decreased with reservoir age. Total emissions were higher in the reservoir lake when compared to the river downstream the dam; however, emissions per unit area, in the first kilometer of the river after the dam, were higher than that in the reservoir. The results showed, despite higher carbon emissions per energy production in the youngest reservoirs, lower emission from hydroelectric reservoirs from the studied region in relation to thermo electrical supply, fueled by coal or fossil fuel. The ratio emission of GHG per MWh produced is an important parameter in evaluating the service provided by hydroelectric reservoir and for energy planning policies. - Highlights: ► Hydroelectric reservoirs construction is growing worldwide. ► The effect of hydropower reservoir in the carbon cycle is dependent on environment characteristics. ► Carbon emissions per energy production are higher in the youngest tropical savannah reservoirs. ► Methane emissions decrease with reservoir age in tropical savannah reservoirs. ► In general, the effect of hydropower in the carbon cycle is lower than other energy sources

  6. Social wasps (Polistinae from Pampa Biome: South Brazil, Northeastern Argentina and Uruguay

    Directory of Open Access Journals (Sweden)

    Alexandre Somavilla

    2017-08-01

    Full Text Available Abstract. This study aimed to determine social wasps’ species from Pampa Biome. Were examined samples of social wasps from south-central of Rio Grande do Sul state (Brazil, parts of Buenos Aires, Entre Rios, Corrientes, Cordoba, Santa Fé and La Pampa provinces (Argentina and in Uruguay maintained in the Coleção Entomológica de Santa Cruz do Sul (Santa Cruz do Sul-Brazil, American Museum of Natural History (USA, Natural History Museum (London-United Kingdom and Muséum National d’Histoire Naturelle (Paris-France. Thirty species were recorded: Agelaia (01, Brachygastra (01, Mischocyttarus (04, Polistes (15, Polybia (08 and Protonectarina (01. Vespas sociais do Bioma Pampa: sul do Brasil, nordeste da Argentina e Uruguai. Resumo. Este estudo objetivou determinar as espécies de vespas sociais provenientes do Bioma Pampa. Foram examinadas vespas sociais provenientes de coletas da região centro-sul do Rio Grande do Sul (Brasil, parte das províncias de Buenos Aires, Entre Rios, Corrientes, Cordoba, Santa Fé e La Pampa (Argentina e Uruguai depositadas na Coleção Entomológica de Santa Cruz do Sul (Santa Cruz do Sul-Brasil, American Museum of Natural History (Nova Iorque-USA, Natural History Museum (Londres-Reino Unido e Muséum National d’Histoire Naturelle (Paris-França. Trinta espécies foram registradas: Agelaia (01, Brachygastra (01, Mischocyttarus (04, Polistes (15, Polybia (08 e Protonectarina (01.

  7. An intercomparison of biogenic emissions estimates from BEIS2 and BIOME: Reconciling the differences

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, J.G. [Alpine Geophysics, Pittsburgh, PA (United States); Emigh, R.A. [Alpine Geophysics, Boulder, CO (United States); Pierce, T.E. [Atmospheric Characterization and Modeling Division/NOAA, Research Triangle Park, NC (United States)

    1996-12-31

    Biogenic emissions play a critical role in urban and regional air quality. For instance, biogenic emissions contribute upwards of 76% of the daily hydrocarbon emissions in the Atlanta, Georgia airshed. The Biogenic Emissions Inventory System-Version 2.0 (BEIS2) and the Biogenic Model for Emissions (BIOME) are two models that compute biogenic emissions estimates. BEIS2 is a FORTRAN-based system, and BIOME is an ARC/INFO{reg_sign} - and SAS{reg_sign}-based system. Although the technical formulations of the models are similar, the models produce different biogenic emissions estimates for what appear to be essentially the same inputs. The goals of our study are the following: (1) Determine why BIOME and BEIS2 produce different emissions estimates; (2) Attempt to understand the impacts that the differences have on the emissions estimates; (3) Reconcile the differences where possible; and (4) Present a framework for the use of BEIS2 and BIOME. In this study, we used the Coastal Oxidant Assessment for Southeast Texas (COAST) biogenics data which were supplied to us courtesy of the Texas Natural Resource Conservation Commission (TNRCC), and we extracted the BEIS2 data for the same domain. We compared the emissions estimates of the two models using their respective data sets BIOME Using TNRCC data and BEIS2 using BEIS2 data.

  8. Some Aspects of the Population Biology of the Green Tiger Prawn Penaeus semisulcatus (De Haan, 1844 from Pilar and Capiz Bays, Northern Panay, West Central Philippines

    Directory of Open Access Journals (Sweden)

    Karen A Villarta

    2006-06-01

    Full Text Available This study is a first report on the population biology of the green tiger prawn Penaeus semisulcatus (de Haan from northern Panay, west central Philippines. The study was conducted for eight months (May to December 2002 whereby total lengths of both male and female P. semisulcatus of various sizes were measured monthly from the catches of municipal trawlers operating at Pilar and Capiz Bays. Based on the Bhattacharya method, a mean growth rate of 0.78 ± 0.28 and 1.45 ± 0.39 mm/day were estimated for males and females, respectively. Using the ELEFAN I method, growth parameters derived for males were L∞ = 263 mm, k = 0.7/yr and a growth index (Ø' of 4.69. On the other hand, growth parameters derived for females were L∞ = 271 mm, k = 1.6/yr and a growth index (Ø' of 5.07.Based on length-converted catch curve analysis, the total mortality (Z of the male population is estimated to be 3.61/yr while that of the females is 5.65/yr. Male prawns showed a higher exploitation rate (0.53 compared to that of the females (0.35 indicating the susceptibility of males to fishing. This study also revealed that trawlers in Pilar and Capiz Bays are already getting small sizes of prawns, without allowing them to reach sexual maturity. Hence, there is a need to increase the present mesh size (2.5 cm of the cod end of trawls in order to avoid growth overfishing, which may occur with continued increase in fishing effort. Furthermore, the recruitment pattern showed two pulses of unequal strengths and time, dividing the year into a 7-5 month pattern. The said pattern, especially for females, may have resulted from a major and minor spawning peak of the said species during the months of June-September and January.

  9. Effects of prescribed fire for pasture management on soil organic matter and biological properties: A 1-year study case in the Central Pyrenees.

    Science.gov (United States)

    Girona-García, Antonio; Badía-Villas, David; Martí-Dalmau, Clara; Ortiz-Perpiñá, Oriol; Mora, Juan Luis; Armas-Herrera, Cecilia M

    2018-03-15

    Prescribed burning has been readopted in the last decade in the Central Pyrenees to stop the regression of subalpine grasslands in favour of shrublands, dominated among others by Echinospartum horridum (Vahl) Rothm. Nevertheless, the effect of this practice on soil properties is uncertain. The aim of this work was to analyse the effects of these burnings on topsoil organic matter and biological properties. Soil sampling was carried out in an autumnal prescribed fire in Buisán (NE-Spain, November 2015). Topsoil was sampled at 0-1cm, 1-2cm and 2-3cm depth in triplicate just before (U), ~1h (B0), 6months (B6) and 12months (B12) after burning. We analysed soil total organic C (TOC), total nitrogen (TN), microbial biomass C (C mic ), soil respiration (SR) and β-D-glucosidase activity. A maximum temperature of 438°C was recorded at soil surface while at 1cm depth only 31°C were reached. Burning significantly decreased TOC (-52%), TN (-44%), C mic (-57%), SR (-72%) and β-D-glucosidase (-66%) at 0-1cm depth while SR was also reduced (-45%) at 1-2cm depth. In B6 and B12, no significant changes in these properties were observed as compared to B0. It can be concluded that the impact of prescribed burning has been significant and sustained over time, although limited to the first two topsoil centimetres. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Concluding remarks: overall impacts on biodiversity and future perspectives for conservation in the Pantanal biome.

    Science.gov (United States)

    Alho, C J R

    2011-04-01

    The Pantanal biome is characterised by seasonal flooding which determines specific ecosystem processes, with the occurrence of adapted plants and animals to the annual shrinking and expansion of habitats due to the seasonal hydrological regime. Biodiversity abundance varies during the dry and wet seasons. The Pantanal's biodiversity is a fundamental component of ecosystem services for human society, including nutrient cycling, fish production, ecotourism, carbon storage, flood control, among others, which are relevant to regional and global environmental consequences. The biome has been impacted by the conversion of natural vegetation into agricultural fields and pasture for cattle raising, with alteration and loss of natural habitats and biodiversity. Major negative impacts occur in uplands, with drastic deforestation of savanna vegetation, where main rivers feeding the Pantanal have their springs. This article discusses future needs and priorities for ecological research, in order to better understand the biome's natural system, to achieve conservation and sustainable use.

  11. Concluding remarks: overall impacts on biodiversity and future perspectives for conservation in the Pantanal biome

    Directory of Open Access Journals (Sweden)

    CJR. Alho

    Full Text Available The Pantanal biome is characterised by seasonal flooding which determines specific ecosystem processes, with the occurrence of adapted plants and animals to the annual shrinking and expansion of habitats due to the seasonal hydrological regime. Biodiversity abundance varies during the dry and wet seasons. The Pantanal's biodiversity is a fundamental component of ecosystem services for human society, including nutrient cycling, fish production, ecotourism, carbon storage, flood control, among others, which are relevant to regional and global environmental consequences. The biome has been impacted by the conversion of natural vegetation into agricultural fields and pasture for cattle raising, with alteration and loss of natural habitats and biodiversity. Major negative impacts occur in uplands, with drastic deforestation of savanna vegetation, where main rivers feeding the Pantanal have their springs. This article discusses future needs and priorities for ecological research, in order to better understand the biome's natural system, to achieve conservation and sustainable use.

  12. BOREAS RSS-8 BIOME-BGC Model Simulations at Tower Flux Sites in 1994

    Science.gov (United States)

    Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Kimball, John

    2000-01-01

    BIOME-BGC is a general ecosystem process model designed to simulate biogeochemical and hydrologic processes across multiple scales (Running and Hunt, 1993). In this investigation, BIOME-BGC was used to estimate daily water and carbon budgets for the BOREAS tower flux sites for 1994. Carbon variables estimated by the model include gross primary production (i.e., net photosynthesis), maintenance and heterotrophic respiration, net primary production, and net ecosystem carbon exchange. Hydrologic variables estimated by the model include snowcover, evaporation, transpiration, evapotranspiration, soil moisture, and outflow. The information provided by the investigation includes input initialization and model output files for various sites in tabular ASCII format.

  13. Where do the treeless tundra areas of northern highlands fit in the global biome system: toward an ecologically natural subdivision of the tundra biome.

    Science.gov (United States)

    Virtanen, Risto; Oksanen, Lauri; Oksanen, Tarja; Cohen, Juval; Forbes, Bruce C; Johansen, Bernt; Käyhkö, Jukka; Olofsson, Johan; Pulliainen, Jouni; Tømmervik, Hans

    2016-01-01

    According to some treatises, arctic and alpine sub-biomes are ecologically similar, whereas others find them highly dissimilar. Most peculiarly, large areas of northern tundra highlands fall outside of the two recent subdivisions of the tundra biome. We seek an ecologically natural resolution to this long-standing and far-reaching problem. We studied broad-scale patterns in climate and vegetation along the gradient from Siberian tundra via northernmost Fennoscandia to the alpine habitats of European middle-latitude mountains, as well as explored those patterns within Fennoscandian tundra based on climate-vegetation patterns obtained from a fine-scale vegetation map. Our analyses reveal that ecologically meaningful January-February snow and thermal conditions differ between different types of tundra. High precipitation and mild winter temperatures prevail on middle-latitude mountains, low precipitation and usually cold winters prevail on high-latitude tundra, and Scandinavian mountains show intermediate conditions. Similarly, heath-like plant communities differ clearly between middle latitude mountains (alpine) and high-latitude tundra vegetation, including its altitudinal extension on Scandinavian mountains. Conversely, high abundance of snowbeds and large differences in the composition of dwarf shrub heaths distinguish the Scandinavian mountain tundra from its counterparts in Russia and the north Fennoscandian inland. The European tundra areas fall into three ecologically rather homogeneous categories: the arctic tundra, the oroarctic tundra of northern heights and mountains, and the genuinely alpine tundra of middle-latitude mountains. Attempts to divide the tundra into two sub-biomes have resulted in major discrepancies and confusions, as the oroarctic areas are included in the arctic tundra in some biogeographic maps and in the alpine tundra in others. Our analyses based on climate and vegetation criteria thus seem to resolve the long-standing biome

  14. Carbon storage in permafrost and soils of the mammoth tundra-steppe biome: role in the global carbon budget

    Science.gov (United States)

    N.S. Zimov; S.A. Zimov; A.E. Zimova; G.M. Zimova; V.I. Chuprynin; F.S. Chapin

    2009-01-01

    During the Last Glacial Maximum (LGM), atmospheric CO2 concentration was 80-100 ppmv lower than in preindustrial times. At that time steppe-tundra was the most extensive biome on Earth. Some authors assume that C storage in that biome was very small, similar to today's deserts, and that the terrestrial carbon (C) reservoir increased at the...

  15. Large-scale impact of climate change vs. land-use change on future biome shifts in Latin America

    NARCIS (Netherlands)

    Boit, Alice; Sakschewski, Boris; Boysen, Lena; Cano-Crespo, Ana; Clement, Jan; Garcia-alaniz, Nashieli; Kok, Kasper; Kolb, Melanie; Langerwisch, Fanny; Rammig, Anja; Sachse, René; Eupen, van Michiel; Bloh, von Werner; Clara Zemp, Delphine; Thonicke, Kirsten

    2016-01-01

    Climate change and land-use change are two major drivers of biome shifts causing habitat and biodiversity loss. What is missing is a continental-scale future projection of the estimated relative impacts of both drivers on biome shifts over the course of this century. Here, we provide such a

  16. Water balance in paired watersheds with eucalyptus and degraded grassland in Pampa biome

    Science.gov (United States)

    Rangelands of the Pampa biome, which cover regions of Argentina, Uruguay and Brazil (176,496 km2 – 2.07% of Brazilian territory and 63% of Rio Grande do Sul State territory, southern region of Brazil) in South America (total area of 750,000 km2), are being substituted by crops and commercial eucalyp...

  17. Selection of native trees for intercropping with coffee in the Atlantic Rainforest biome

    NARCIS (Netherlands)

    Souza, de H.N.; Cardoso, I.M.; Fernandes, J.M.; Garcia, F.C.P.; Bonfim, V.R.; Santos, A.C.; Carvalho, A.F.; Mendonca, E.S.

    2010-01-01

    A challenge in establishing agroforestry systems is ensuring that farmers are interested in the tree species, and are aware of how to adequately manage these species. This challenge was tackled in the Atlantic Rainforest biome (Brazil), where a participatory trial with agroforestry coffee systems

  18. A new species of Andocaeculus (Acari, Caeculidae) from the Pampa biome, southern Brazil

    OpenAIRE

    Ana Paula Ott; Ricardo Ott

    2014-01-01

    A new caeculid species Andocaeculus caioi sp. nov. is described from Pampa biome in south Brazil. The species of this family are usually large and strong sclerotized mites with robust and spinulose legs I and II. Until now records of species for South America were known only from Chile and Argentina.

  19. Hantavirus pulmonary syndrome and rodent reservoirs in the savanna-like biome of Brazil's southeastern region.

    Science.gov (United States)

    Limongi, J E; Oliveira, R C; Guterres, A; Costa Neto, S F; Fernandes, J; Vicente, L H B; Coelho, M G; Ramos, V N; Ferreira, M S; Bonvicino, C R; D'Andrea, P S; Lemos, E R S

    2016-04-01

    This paper describes the diversity of rodent fauna in an area endemic for hantavirus cardiopulmonary syndrome (HCPS) in Brazil, the population dynamics and the relationship of rodents with hantavirus in the Cerrado (savanna-like) biome. Additionally, an analysis is made of the partial S segment sequences of the hantaviruses obtained from serologically confirmed human HCPS cases and from rodent specimens. Rodents were collected during four campaigns. Human serum samples were collected from suspected cases of HCPS at hospitals in the state of Minas Gerais. The samples antibody-reactive by ELISA were processed by RT-PCR. The PCR product was amplified and sequenced. Hantavirus was detected only in Necromys lasiurus, the wild rodent species most prevalent in the Cerrado biome (min-max: 50-83·7%). All the six human serum samples were hantavirus seropositive and five showed amplified PCR products. The analysis of the nucleotide sequences showed the circulation of a single genotype, the Araraquara hantavirus. The environmental changes that have occurred in the Cerrado biome in recent decades have favoured N. lasiurus in interspecific competition of habitats, thus increasing the risk of contact between humans and rodent species infected with hantavirus. Our data corroborate the definition of N. lasiurus as the main hantavirus reservoir in the Cerrado biome.

  20. Extreme precipitation patterns and reductions of terrestrial ecosystem production across biomes

    Science.gov (United States)

    Yongguang Zhang; M. Susan Moran; Mark A. Nearing; Guillermo E. Ponce Campos; Alfredo R. Huete; Anthony R. Buda; David D. Bosch; Stacey A. Gunter; Stanley G. Kitchen; W. Henry McNab; Jack A. Morgan; Mitchel P. McClaran; Diane S. Montoya; Debra P.C. Peters; Patrick J. Starks

    2013-01-01

    Precipitation regimes are predicted to shift to more extreme patterns that are characterized by more heavy rainfall events and longer dry intervals, yet their ecological impacts on vegetation production remain uncertain across biomes in natural climatic conditions. This in situ study investigated the effects of these climatic conditions on aboveground net primary...

  1. The Biome Project: Developing a Legitimate Parallel Curriculum for Physical Education and Life Sciences

    Science.gov (United States)

    Hastie, Peter Andrew

    2013-01-01

    The purpose of this article is to describe the outcomes of a parallel curriculum project between life sciences and physical education. Throughout a 6-week period, students in grades two through five became members of teams that represented different animal species and biomes, and concurrently participated in a season of gymnastics skills and…

  2. Guide to the literature on research in the grassland biome of South Africa

    CSIR Research Space (South Africa)

    Tainton, MN

    1984-12-01

    Full Text Available the development of an understanding of how these communities can best be managed to ensure their sustained producti¬vity, or indeed to increase their productivity. This publication serves to highlight the main work which has been undertaken in this biome...

  3. Remotely sensed vegetation phenology for describing and predicting the biomes of South Africa

    CSIR Research Space (South Africa)

    Wessels, Konrad J

    2011-02-01

    Full Text Available the distribution of the recently redefined biomes be predicted based on remotely sensed, phenology and productivity metrics? Ten-day, 1 km, NDVI AVHRR were analysed for the period 1985 to 2000. Phenological metrics such as start, end and length of the growing...

  4. Modeling Carbon and Water Budgets in the Lushi Basin with Biome-BGC

    Institute of Scientific and Technical Information of China (English)

    Dong Wenjuan; Qi Ye; Li Huimin; Zhou Dajie; Shi Duanhua; Sun Liying

    2005-01-01

    In this article, annual evapotranspiration (ET) and net primary productivity (NPP) of four types of vegetation were estimated for the Lushi basin,a subbasin of the Yellow River in China. These four vegetation types include: deciduous broadleaf forest,evergreen needle leaf forest, dwarf shrub and grass.Biome-BGC--a biogeochemical process model was used to calculate annual ET and NPP for each vegetation type in the study area from 1954 to 2000.Daily microclimate data of 47 years monitored by Lushi meteorological station was extrapolated to cover the basin using MT-CLIM, a mountain microclimate simulator. The output files of MTCLIM were used to feed Biome-BGC. We used average ecophysiological values of each type of vegetation supplied by Numerical Terradynamic Simulation Group (NTSG) in the University of Montana as input ecophysiological constants file.The estimates of daily NPP in early July and annual ET on these four biome groups were compared respectively with field measurements and other studies.Daily gross primary production (GPP) of evergreen needle leaf forest measurements were very dose to the output of Biome-BGC, but measurements of broadleaf forest and dwarf shrub were much smaller than the simulation result. Simulated annual ET and NPP had a significant correlation with precipitation,indicating precipitation is the major environmental factor affecting ET and NPP in the study area.Precipitation also is the key climatic factor for the interannual ET and NPP variations.

  5. Global negative vegetation feedback to climate warming responses of leaf litter decomposition rates in cold biomes.

    NARCIS (Netherlands)

    Cornelissen, J.H.C.; van Bodegom, P.M.; Aerts, R.; Gallaghan, T.V.; van Logtestijn, R.S.P; Alatalo, J.; Chapin, F.S. III; Gerdol, R.; Gudmundsson, J.; Gwynn-Jones, D.; Hartley, A.E.; Hik, D.S.; Hofgaard, A.; Jonsdottir, I.S.; Karlsson, S.; Klein, J.A.; Laundre, J.; Magnusson, B.; Michelsel, A.; Molau, U.; Onipchenko, V.G.; Quested, H.M.; Sandvik, S.M.; Schmidt, I.K.; Shaver, G.R.; Solhleim, B.; Soudzilovskaia, N.A.; Stenstrom, A.; Tolvanen, A.; Totland, O.; Wada, N.; Welker, J.M.; Zhao, X.; Team, M.O.L.

    2007-01-01

    Whether climate change will turn cold biomes from large long-term carbon sinks into sources is hotly debated because of the great potential for ecosystem-mediated feedbacks to global climate. Critical are the direction, magnitude and generality of climate responses of plant litter decomposition.

  6. The freezer defrosting: global warming and litter decomposition rates in cold biomes. Essay review.

    NARCIS (Netherlands)

    Aerts, R.

    2006-01-01

    1 Decomposition of plant litter, a key component of the global carbon budget, is hierarchically controlled by the triad: climate > litter quality > soil organisms. Given the sensitivity of decomposition to temperature, especially in cold biomes, it has been hypothesized that global warming will lead

  7. A reconstruction of Colombian biomes derived from modern pollen data along an altitude gradient

    NARCIS (Netherlands)

    Marchant, R.; Berrío, J.C.; Cleef, A.M.; Duivenvoorden, J.; Helmens, K.; Hooghiemstra, H.; Kuhry, P.; Melief, B.; Schreve-Brinkman, E.; Geel, van B.; Reenen, van G.; Hammen, van der T.

    2001-01-01

    Biomes are reconstructed in Colombia from modern (core-top) pollen data derived from 22 sites along an altitudinal gradient (2000–4100 m) that encompasses the tree line. The `biomization' methodology is described in a stepwise manner that details the reconstruction of vegetation along an altitudinal

  8. A reconstruction of Colombian biomes derived from modern pollen data along an altitude gradient.

    NARCIS (Netherlands)

    Marchant, R.A.; Behling, H.; Berrio Mogollon, J.C.; Cleef, A.M.; Duivenvoorden, J.F.; van Geel, B.; van der Hammen, T.; Hooghiemstra, H.; Kuhry, P.; Melief, B.M.; van Reenen, G.B.A.; Wille, M.

    2001-01-01

    Biomes are reconstructed in Colombia from modern (core-top) pollen data derived from twenty-two sites along an altitudinal gradient (2000 to 4100 m) that encompasses the tree line. The 'biomization' methodology is described in a stepwise manner that details the reconstruction of vegetation along an

  9. Pollen-based biome reconstructions for Colombia at 3000, 6000, 15 000 and 18 000 14C yr ago : Late Quaternary tropical vegetation dynamics

    NARCIS (Netherlands)

    Marchant, R.; Behling, H.; Berrío, J.C.; Cleef, A.M.; Duivenvoorden, J.; Hooghiemstra, H.; Kuhry, P.; Melief, B.; Schreve-Brinkman, E.; Geel, van B.; Hammen, van der T.; Reenen, van G.

    2002-01-01

    Colombian biomes are reconstructed at 45 sites from the modern period extending to the Last Glacial Maximum (LGM). The basis for our reconstruction is pollen data assigned to plant functional types and biomes at six 3000-yr intervals. A reconstruction of modern biomes is used to check the treatment

  10. Estimating 40 years of nitrogen deposition in global biomes using the SCIAMACHY NO2 column

    Science.gov (United States)

    Lu, Xuehe; Zhang, Xiuying; Liu, Jinxun; Jin, Jiaxin

    2016-01-01

    Owing to human activity, global nitrogen (N) cycles have been altered. In the past 100 years, global N deposition has increased. Currently, the monitoring and estimating of N deposition and the evaluation of its effects on global carbon budgets are the focus of many researchers. NO2 columns retrieved by space-borne sensors provide us with a new way of exploring global N cycles and these have the ability to estimate N deposition. However, the time range limitation of NO2 columns makes the estimation of long timescale N deposition difficult. In this study we used ground-based NOx emission data to expand the density of NO2columns, and 40 years of N deposition (1970–2009) was inverted using the multivariate linear model with expanded NO2 columns. The dynamic of N deposition was examined in both global and biome scales. The results show that the average N deposition was 0.34 g N m–2 year–1 in the 2000s, which was an increase of 38.4% compared with the 1970s’. The total N deposition in different biomes is unbalanced. N deposition is only 38.0% of the global total in forest biomes; this is made up of 25.9%, 11.3, and 0.7% in tropical, temperate, and boreal forests, respectively. As N-limited biomes, there was little increase of N deposition in boreal forests. However, N deposition has increased by a total of 59.6% in tropical forests and croplands, which are N-rich biomes. Such characteristics may influence the effects on global carbon budgets.

  11. Forest carbon emissions from cropland expansion in the Brazilian Cerrado biome

    Science.gov (United States)

    Noojipady, Praveen; Morton, C. Douglas; Macedo, N. Marcia; Victoria, C. Daniel; Huang, Chengquan; Gibbs, K. Holly; Edson Bolfe, L.

    2017-02-01

    Land use, land use change, and forestry accounted for two-thirds of Brazil’s greenhouse gas emissions profile in 2005. Amazon deforestation has declined by more than 80% over the past decade, yet Brazil’s forests extend beyond the Amazon biome. Rapid expansion of cropland in the neighboring Cerrado biome has the potential to undermine climate mitigation efforts if emissions from dry forest and woodland conversion negate some of the benefits of avoided Amazon deforestation. Here, we used satellite data on cropland expansion, forest cover, and vegetation carbon stocks to estimate annual gross forest carbon emissions from cropland expansion in the Cerrado biome. Nearly half of the Cerrado met Brazil’s definition of forest cover in 2000 (≥0.5 ha with ≥10% canopy cover). In areas of established crop production, conversion of both forest and non-forest Cerrado formations for cropland declined during 2003-2013. However, forest carbon emissions from cropland expansion increased over the past decade in Matopiba, a new frontier of agricultural production that includes portions of Maranhão, Tocantins, Piauí, and Bahia states. Gross carbon emissions from cropland expansion in the Cerrado averaged 16.28 Tg C yr-1 between 2003 and 2013, with forest-to-cropland conversion accounting for 29% of emissions. The fraction of forest carbon emissions from Matopiba was much higher; between 2010-2013, large-scale cropland conversion in Matopiba contributed 45% of total Cerrado forest carbon emissions. Carbon emissions from Cerrado-to-cropland transitions offset 5%-7% of the avoided emissions from reduced Amazon deforestation rates during 2011-2013. Comprehensive national estimates of forest carbon fluxes, including all biomes, are critical to detect cross-biome leakage within countries and achieve climate mitigation targets to reduce emissions from land use, land use change, and forestry.

  12. Temporal Changes in Coupled Vegetation Phenology and Productivity are Biome-Specific in the Northern Hemisphere

    Directory of Open Access Journals (Sweden)

    Lanhui Wang

    2017-12-01

    Full Text Available Global warming has greatly stimulated vegetation growth through both extending the growing season and promoting photosynthesis in the Northern Hemisphere (NH. Analyzing the combined dynamics of such trends can potentially improve our current understanding on changes in vegetation functioning and the complex relationship between anthropogenic and climatic drivers. This study aims to analyze the relationships (long-term trends and correlations of length of vegetation growing season (LOS and vegetation productivity assessed by the growing season NDVI integral (GSI in the NH (>30°N to study any dependency of major biomes that are characterized by different imprint from anthropogenic influence. Spatial patterns of converging/diverging trends in LOS and GSI and temporal changes in the coupling between LOS and GSI are analyzed for major biomes at hemispheric and continental scales from the third generation Global Inventory Monitoring and Modeling Studies (GIMMS Normalized Difference Vegetation Index (NDVI dataset for a 32-year period (1982–2013. A quarter area of the NH is covered by converging trends (consistent significant trends in LOS and GSI, whereas diverging trends (opposing significant trends in LOS and GSI cover about 6% of the region. Diverging trends are observed mainly in high latitudes and arid/semi-arid areas of non-forest biomes (shrublands, savannas, and grasslands, whereas forest biomes and croplands are primarily characterized by converging trends. The study shows spatially-distinct and biome-specific patterns between the continental land masses of Eurasia (EA and North America (NA. Finally, areas of high positive correlation between LOS and GSI showed to increase during the period of analysis, with areas of significant positive trends in correlation being more widespread in NA as compared to EA. The temporal changes in the coupled vegetation phenology and productivity suggest complex relationships and interactions that are induced

  13. Aura-biomes are present in the water layer above coral reef benthic macro-organisms.

    Science.gov (United States)

    Walsh, Kevin; Haggerty, J Matthew; Doane, Michael P; Hansen, John J; Morris, Megan M; Moreira, Ana Paula B; de Oliveira, Louisi; Leomil, Luciana; Garcia, Gizele D; Thompson, Fabiano; Dinsdale, Elizabeth A

    2017-01-01

    As coral reef habitats decline worldwide, some reefs are transitioning from coral- to algal-dominated benthos with the exact cause for this shift remaining elusive. Increases in the abundance of microbes in the water column has been correlated with an increase in coral disease and reduction in coral cover. Here we investigated how multiple reef organisms influence microbial communities in the surrounding water column. Our study consisted of a field assessment of microbial communities above replicate patches dominated by a single macro-organism. Metagenomes were constructed from 20 L of water above distinct macro-organisms, including (1) the coral Mussismilia braziliensis , (2) fleshy macroalgae ( Stypopodium , Dictota and Canistrocarpus ), (3) turf algae, and (4) the zoanthid Palythoa caribaeorum and were compared to the water microbes collected 3 m above the reef. Microbial genera and functional potential were annotated using MG-RAST and showed that the dominant benthic macro-organisms influence the taxa and functions of microbes in the water column surrounding them, developing a specific "aura-biome". The coral aura-biome reflected the open water column, and was associated with Synechococcus and functions suggesting oligotrophic growth, while the fleshy macroalgae aura-biome was associated with Ruegeria , Pseudomonas, and microbial functions suggesting low oxygen conditions. The turf algae aura-biome was associated with Vibrio, Flavobacterium, and functions suggesting pathogenic activity, while zoanthids were associated with Alteromonas and functions suggesting a stressful environment. Because each benthic organism has a distinct aura-biome, a change in benthic cover will change the microbial community of the water, which may lead to either the stimulation or suppression of the recruitment of benthic organisms.

  14. Forgotten forests - issues and prospects in biome mapping using Seasonally Dry Tropical Forests as a case study

    Science.gov (United States)

    2011-01-01

    Background South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF) biome using herbarium data of habitat specialist species. Results Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1) poor spatial resolution, and (2) poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM) approach where georeferenced herbarium data is used in conjunction with bioclimatic data. Conclusions Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps in silico. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in biome mapping, and could be

  15. Forgotten forests--issues and prospects in biome mapping using Seasonally Dry Tropical Forests as a case study.

    Science.gov (United States)

    Särkinen, Tiina; Iganci, João R V; Linares-Palomino, Reynaldo; Simon, Marcelo F; Prado, Darién E

    2011-11-24

    South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF) biome using herbarium data of habitat specialist species. Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1) poor spatial resolution, and (2) poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM) approach where georeferenced herbarium data is used in conjunction with bioclimatic data. Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps in silico. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in biome mapping, and could be particularly useful for mapping

  16. Forgotten forests - issues and prospects in biome mapping using Seasonally Dry Tropical Forests as a case study

    Directory of Open Access Journals (Sweden)

    Särkinen Tiina

    2011-11-01

    Full Text Available Abstract Background South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF biome using herbarium data of habitat specialist species. Results Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1 poor spatial resolution, and (2 poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM approach where georeferenced herbarium data is used in conjunction with bioclimatic data. Conclusions Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps in silico. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in

  17. Invasion of a Legume Ecosystem Engineer in a Cold Biome Alters Plant Biodiversity

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    Vanessa M. S. Vetter

    2018-06-01

    Full Text Available Plant ecosystem engineers are widely used to combat land degradation. However, the ability of those plants to modulate limiting abiotic and biotic resources of other species can cause damage to ecosystems in which they become invasive. Here, we use Lupinus nootkatensis as example to estimate and project the hazardous potential of nitrogen fixing herbaceous plants in a sub-polar oceanic climate. L. nootkatensis was introduced to Iceland in the 1940s to address erosion problems and foster reforestation, but subsequently became a high-latitude invader. In a local field survey, we quantified the impact of L. nootkatensis invasion at three different cover levels (0, 10–50, and 51–100% upon native plant diversity, richness, and community composition of heath-, wood-, and grasslands using a pairwise comparison design and comparisons of means. Afterward, we scaled impacts up to the ecosystem and landscape level by relating occurrences of L. nootkatensis to environmental and human-mediated variables across Iceland using a species distribution model. Plant diversity was significantly deteriorated under high lupine cover levels of the heath- and woodland, but not in the grassland. Plant species richness of the most diverse habitat, the heathland, linearly decreased with lupine cover level. The abundance of small rosettes, cushion plants, orchids, and small woody long-lived plants of the heath declined with invader presence, while the abundance of late successional species and widespread nitrophilous ruderals in wood- and grasslands increased. Distribution modeling revealed 13.3% of Iceland’s land surface area to be suitable lupine habitat. Until 2061–2080, this area will more than double and expand significantly into the Central Highlands due to human mediation and increasingly favorable climatic conditions. Species-rich habitats showed a loss of plant species diversity and richness as well as a change in community composition even in low lupine

  18. Future changes in South American biomass distributions, biome distributions and plant trait spectra is dependent on applied atmospheric forcings.

    Science.gov (United States)

    Langan, Liam; Scheiter, Simon; Higgins, Steven

    2017-04-01

    It remains poorly understood why the position of the forest-savanna biome boundary, in a domain defined by precipitation and temperature, differs in South America, Africa and Australia. Process based Dynamic Global Vegetation Models (DGVMs) are a valuable tool to investigate the determinants of vegetation distributions, however, many DGVMs fail to predict the spatial distribution or indeed presence of the South American savanna biome. Evidence suggests fire plays a significant role in mediating forest-savanna biome boundaries, however, fire alone appear to be insufficient to predict these boundaries in South America. We hypothesize that interactions between precipitation, constraints on tree rooting depth and fire, affect the probability of savanna occurrence and the position of the savanna-forest boundary. We tested our hypotheses at tropical forest and savanna sites in Brazil and Venezuela using a novel DGVM, aDGVM2, which allows plant trait spectra, constrained by trade-offs between traits, to evolve in response to abiotic and biotic conditions. Plant hydraulics is represented by the cohesion-tension theory, this allowed us to explore how soil and plant hydraulics control biome distributions and plant traits. The resulting community trait distributions are emergent properties of model dynamics. We showed that across much of South America the biome state is not determined by climate alone. Interactions between tree rooting depth, fire and precipitation affected the probability of observing a given biome state and the emergent traits of plant communities. Simulations where plant rooting depth varied in space provided the best match to satellite derived biomass estimates and generated biome distributions that reproduced contemporary biome maps well. Future projections showed that biomass distributions, biome distributions and plant trait spectra will change, however, the magnitude of these changes are highly dependent on the applied atmospheric forcings.

  19. Synthetic vision and memory model for virtual human - biomed 2010.

    Science.gov (United States)

    Zhao, Yue; Kang, Jinsheng; Wright, David

    2010-01-01

    This paper describes the methods and case studies of a novel synthetic vision and memory model for virtual human. The synthetic vision module simulates the biological / optical abilities and limitations of the human vision. The module is based on a series of collision detection between the boundary of virtual humans field of vision (FOV) volume and the surface of objects in a recreated 3D environment. The memory module simulates a short-term memory capability by employing a simplified memory structure (first-in-first-out stack). The synthetic vision and memory model has been integrated into a virtual human modelling project, Intelligent Virtual Modelling. The project aimed to improve the realism and autonomy of virtual humans.

  20. Measurement of the Ecological Integrity of Cerrado Streams Using Biological Metrics and the Index of Habitat Integrity

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    Deusiano Florêncio dos Reis

    2017-01-01

    Full Text Available Generally, aquatic communities reflect the effects of anthropogenic changes such as deforestation or organic pollution. The Cerrado stands among the most threatened ecosystems by human activities in Brazil. In order to evaluate the ecological integrity of the streams in a preserved watershed in the Northern Cerrado biome corresponding to a mosaic of ecosystems in transition to the Amazonia biome in Brazil, biological metrics related to diversity, structure, and sensitivity of aquatic macroinvertebrates were calculated. Sampling included collections along stretches of 200 m of nine streams and measurements of abiotic variables (temperature, electrical conductivity, pH, total dissolved solids, dissolved oxygen, and discharge and the Index of Habitat Integrity (HII. The values of the abiotic variables and the HII indicated that most of the streams have good ecological integrity, due to high oxygen levels and low concentrations of dissolved solids and electric conductivity. Two streams showed altered HII scores mainly related to small dams for recreational and domestic use, use of Cerrado natural pasture for cattle raising, and spot deforestation in bathing areas. However, this finding is not reflected in the biological metrics that were used. Considering all nine streams, only two showed satisfactory ecological quality (measured by Biological Monitoring Working Party (BMWP, total richness, and EPT (Ephemeroptera, Plecoptera, and Trichoptera richness, only one of which had a low HII score. These results indicate that punctual measures of abiotic parameters do not reveal the long-term impacts of anthropic activities in these streams, including related fire management of pasture that annually alters the vegetation matrix and may act as a disturbance for the macroinvertebrate communities. Due to this, biomonitoring of low order streams in Cerrado ecosystems of the Northern Central Brazil by different biotic metrics and also physical attributes of the

  1. Remote Sensing of the Urban Heat Island Effect Across Biomes in the Continental USA

    Science.gov (United States)

    Imhoff, Marc L.; Zhang, Ping; Wolfe, Robert E.; Bounoua, Lahouari

    2010-01-01

    Impervious surface area (ISA) from the Landsat TM-based NLCD 2001 dataset and land surface temperature (LST) from MODIS averaged over three annual cycles (2003-2005) are used in a spatial analysis to assess the urban heat island (UHI) skin temperature amplitude and its relationship to development intensity, size, and ecological setting for 38 of the most populous cities in the continental United States. Development intensity zones based on %ISA are defined for each urban area emanating outward from the urban core to the nonurban rural areas nearby and used to stratify sampling for land surface temperatures and NDVI. Sampling is further constrained by biome and elevation to insure objective intercomparisons between zones and between cities in different biomes permitting the definition of hierarchically ordered zones that are consistent across urban areas in different ecological setting and across scales. We find that ecological context significantly influences the amplitude of summer daytime UHI (urban-rural temperature difference) the largest (8 C average) observed for cities built in biomes dominated by temperate broadleaf and mixed forest. For all cities combined, ISA is the primary driver for increase in temperature explaining 70% of the total variance in LST. On a yearly average, urban areas are substantially warmer than the non-urban fringe by 2.9 C, except for urban areas in biomes with arid and semiarid climates. The average amplitude of the UHI is remarkably asymmetric with a 4.3 C temperature difference in summer and only 1.3 C in winter. In desert environments, the LST's response to ISA presents an uncharacteristic "U-shaped" horizontal gradient decreasing from the urban core to the outskirts of the city and then increasing again in the suburban to the rural zones. UHI's calculated for these cities point to a possible heat sink effect. These observational results show that the urban heat island amplitude both increases with city size and is seasonally

  2. Microestructura y propiedades mecánicas del SiC biomórfico obtenido a partir de eucalipto

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    Presas, M.

    2005-12-01

    Full Text Available The development of cellular ceramics with a biological structure, like bones and wood, has been a matter of interest in recent years. A low density highly interconnected structure, perfected by evolution, rises as the principal advantage of these materials. In the case of biomimetic SiC (biomorphic SiC, or bioSiC, the fabrication process technique is quite simple: a piece of wood is pyrolysed and is infiltrated with molten silicon after, the final product is a composite Si/SiC, which replicates the wood anisotropic microstructure This work focus on the mechanical properties of bioSiC fabricated using eucalyptus wood as precursor (hard wood with a bimodal channel distribution. It has been studied the mechanical behavior of this bioSiC (compression strength, flexure strength, fracture toughness and elastic modulus between 25 and 1350 oC. It is also discussed the relationship between mechanical behavior of the material and its microstructure.

    El desarrollo de materiales cerámicos con una estructura de tipo celular, similar a la del hueso o la madera, ha sido una cuestión que ha suscitado un gran interés en los últimos años. Su atractivo se debe al hecho de poseer una estructura porosa altamente interconectada de baja densidad, perfeccionada por la evolución. En el caso del SiC biomórfico (bio-SiC el proceso de fabricación es sencillo: se piroliza una pieza de madera y a continuación se inyecta con silicio líquido, el material así obtenido es un compuesto Si/SiC en el que el SiC mimetiza la estructura de la madera original. En este trabajo se estudian las propiedades mecánicas del SiC biomórfico fabricado a partir de eucalipto (madera dura con una distribución bimodal de poros. Se ha estudiado el comportamiento mecánico del mismo (resistencia a compresión, resistencia a flexión, tenacidad de fractura y módulo de elasticidad entre 25 y 1350 oC. Asimismo, se discute la relación entre el comportamiento mecánico del material y

  3. Microbial Diversity in Cerrado Biome (Neotropical Savanna Soils.

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    Alinne Pereira de Castro

    Full Text Available The Cerrado, the largest savanna region in South America, is located in central Brazil. Cerrado physiognomies, which range from savanna grasslands to forest formations, combined with the highly weathered, acidic clay Cerrado soils form a unique ecoregion. In this study, high-throughput sequencing of ribosomal RNA genes was combined with shotgun metagenomic analysis to explore the taxonomic composition and potential functions of soil microbial communities in four different vegetation physiognomies during both dry and rainy seasons. Our results showed that changes in bacterial, archaeal, and fungal community structures in cerrado denso, cerrado sensu stricto, campo sujo, and gallery forest soils strongly correlated with seasonal patterns of soil water uptake. The relative abundance of AD3, WPS-2, Planctomycetes, Thermoprotei, and Glomeromycota typically decreased in the rainy season, whereas the relative abundance of Proteobacteria and Ascomycota increased. In addition, analysis of shotgun metagenomic data revealed a significant increase in the relative abundance of genes associated with iron acquisition and metabolism, dormancy, and sporulation during the dry season, and an increase in the relative abundance of genes related to respiration and DNA and protein metabolism during the rainy season. These gene functional categories are associated with adaptation to water stress. Our results further the understanding of how tropical savanna soil microbial communities may be influenced by vegetation covering and temporal variations in soil moisture.

  4. Estimation of Carbon Flux of Forest Ecosystem over Qilian Mountains by BIOME-BGC Model

    Science.gov (United States)

    Yan, Min; Tian, Xin; Li, Zengyuan; Chen, Erxue; Li, Chunmei

    2014-11-01

    The gross primary production (GPP) and net ecosystem exchange (NEE) are important indicators for carbon fluxes. This study aims at evaluating the forest GPP and NEE over the Qilian Mountains using meteorological, remotely sensed and other ancillary data at large scale. To realize this, the widely used ecological-process-based model, Biome-BGC, and remote-sensing-based model, MODIS GPP algorithm, were selected for the simulation of the forest carbon fluxes. The combination of these two models was based on calibrating the Biome-BGC by the optimized MODIS GPP algorithm. The simulated GPP and NEE values were evaluated against the eddy covariance observed GPPs and NEEs, and the well agreements have been reached, with R2=0.76, 0.67 respectively.

  5. Candidatus Rickettsia andeanae, a spotted fever group agent infecting Amblyomma parvum ticks in two Brazilian biomes

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    Fernanda Aparecida Nieri-Bastos

    2014-04-01

    Full Text Available Adult ticks of the species Amblyomma parvum were collected from the vegetation in the Pantanal biome (state of Mato Grosso do Sul and from horses in the Cerrado biome (state of Piauí in Brazil. The ticks were individually tested for rickettsial infection via polymerase chain reaction (PCR targeting three rickettsial genes, gltA, ompA and ompB. Overall, 63.5% (40/63 and 66.7% (2/3 of A. parvum ticks from Pantanal and Cerrado, respectively, contained rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to the corresponding fragments of the gltA, ompA and ompB genes of Candidatus Rickettsia andeanae. This report is the first to describe Ca. R. andeanae in Brazil.

  6. A hierarchical analysis of terrestrial ecosystem model Biome-BGC: Equilibrium analysis and model calibration

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, Peter E [ORNL; Wang, Weile [ORNL; Law, Beverly E. [Oregon State University; Nemani, Ramakrishna R [NASA Ames Research Center

    2009-01-01

    The increasing complexity of ecosystem models represents a major difficulty in tuning model parameters and analyzing simulated results. To address this problem, this study develops a hierarchical scheme that simplifies the Biome-BGC model into three functionally cascaded tiers and analyzes them sequentially. The first-tier model focuses on leaf-level ecophysiological processes; it simulates evapotranspiration and photosynthesis with prescribed leaf area index (LAI). The restriction on LAI is then lifted in the following two model tiers, which analyze how carbon and nitrogen is cycled at the whole-plant level (the second tier) and in all litter/soil pools (the third tier) to dynamically support the prescribed canopy. In particular, this study analyzes the steady state of these two model tiers by a set of equilibrium equations that are derived from Biome-BGC algorithms and are based on the principle of mass balance. Instead of spinning-up the model for thousands of climate years, these equations are able to estimate carbon/nitrogen stocks and fluxes of the target (steady-state) ecosystem directly from the results obtained by the first-tier model. The model hierarchy is examined with model experiments at four AmeriFlux sites. The results indicate that the proposed scheme can effectively calibrate Biome-BGC to simulate observed fluxes of evapotranspiration and photosynthesis; and the carbon/nitrogen stocks estimated by the equilibrium analysis approach are highly consistent with the results of model simulations. Therefore, the scheme developed in this study may serve as a practical guide to calibrate/analyze Biome-BGC; it also provides an efficient way to solve the problem of model spin-up, especially for applications over large regions. The same methodology may help analyze other similar ecosystem models as well.

  7. Ecological consequences of the expansion of N2-fixing plants in cold biomes

    Science.gov (United States)

    Hiltbrunner, Erika; Aerts, Rien; Bühlmann, Tobias; Huss-Danell, Kerstin; Magnusson, Borgthor; Myrold, David D.; Reed, Sasha C.; Sigurdsson, Bjarni D.; Körner, Christian

    2014-01-01

    Research in warm-climate biomes has shown that invasion by symbiotic dinitrogen (N2)-fixing plants can transform ecosystems in ways analogous to the transformations observed as a consequence of anthropogenic, atmospheric nitrogen (N) deposition: declines in biodiversity, soil acidification, and alterations to carbon and nutrient cycling, including increased N losses through nitrate leaching and emissions of the powerful greenhouse gas nitrous oxide (N2O). Here, we used literature review and case study approaches to assess the evidence for similar transformations in cold-climate ecosystems of the boreal, subarctic and upper montane-temperate life zones. Our assessment focuses on the plant genera Lupinus and Alnus, which have become invasive largely as a consequence of deliberate introductions and/or reduced land management. These cold biomes are commonly located in remote areas with low anthropogenic N inputs, and the environmental impacts of N2-fixer invasion appear to be as severe as those from anthropogenic N deposition in highly N polluted areas. Hence, inputs of N from N2 fixation can affect ecosystems as dramatically or even more strongly than N inputs from atmospheric deposition, and biomes in cold climates represent no exception with regard to the risk of being invaded by N2-fixing species. In particular, the cold biomes studied here show both a strong potential to be transformed by N2-fixing plants and a rapid subsequent saturation in the ecosystem’s capacity to retain N. Therefore, analogous to increases in N deposition, N2-fixing plant invasions must be deemed significant threats to biodiversity and to environmental quality.

  8. Reply: “Use of BIOME-BGC to simulate Mediterranean forest carbon stocks”

    OpenAIRE

    Maselli F; Salvati R; Barbati A; Chirici G; Chiesi M

    2011-01-01

    The current note responds to the critical contribution of Dr. Eastaugh on Chiesi et al. (Chiesi et al. 2011). That paper did not aim at applying BIOME-BGC to simulate stand growth, which requires a thorough modification of the model functions. In contrast, only a parameter setting was changed in order to adjust the predicted carbon storages during the simulation of quasi-equilibrium conditions. The adjustment was calibrated on volume statistics derived from the Tuscany forest inventory and is...

  9. Record of the Buff-fronted Owl (Aegolius harrisii in the Pampa Biome, southern Brazil

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    Marluci Müller Rebelato

    2011-02-01

    Full Text Available We present the second record of the Buff-fronted Owl (Aegolius harrisii in the Pampa Biome, South Brazil. On 17 January 2010 an adult male was found dead at the roadside along the BR-290, São Gabriel municipality, center-east of Rio Grande do Sul state. The specimen probably collided with a car when using the area for foraging. The record reported here agrees with the suggestion that A. harrisii can use disturbed and open areas.

  10. Aura-biomes are present in the water layer above coral reef benthic macro-organisms

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    Kevin Walsh

    2017-08-01

    Full Text Available As coral reef habitats decline worldwide, some reefs are transitioning from coral- to algal-dominated benthos with the exact cause for this shift remaining elusive. Increases in the abundance of microbes in the water column has been correlated with an increase in coral disease and reduction in coral cover. Here we investigated how multiple reef organisms influence microbial communities in the surrounding water column. Our study consisted of a field assessment of microbial communities above replicate patches dominated by a single macro-organism. Metagenomes were constructed from 20 L of water above distinct macro-organisms, including (1 the coral Mussismilia braziliensis, (2 fleshy macroalgae (Stypopodium, Dictota and Canistrocarpus, (3 turf algae, and (4 the zoanthid Palythoa caribaeorum and were compared to the water microbes collected 3 m above the reef. Microbial genera and functional potential were annotated using MG-RAST and showed that the dominant benthic macro-organisms influence the taxa and functions of microbes in the water column surrounding them, developing a specific “aura-biome”. The coral aura-biome reflected the open water column, and was associated with Synechococcus and functions suggesting oligotrophic growth, while the fleshy macroalgae aura-biome was associated with Ruegeria, Pseudomonas, and microbial functions suggesting low oxygen conditions. The turf algae aura-biome was associated with Vibrio, Flavobacterium, and functions suggesting pathogenic activity, while zoanthids were associated with Alteromonas and functions suggesting a stressful environment. Because each benthic organism has a distinct aura-biome, a change in benthic cover will change the microbial community of the water, which may lead to either the stimulation or suppression of the recruitment of benthic organisms.

  11. Genetic diversity of bats coronaviruses in the Atlantic Forest hotspot biome, Brazil.

    Science.gov (United States)

    Góes, Luiz Gustavo Bentim; Campos, Angélica Cristine de Almeida; Carvalho, Cristiano de; Ambar, Guilherme; Queiroz, Luzia Helena; Cruz-Neto, Ariovaldo Pereira; Munir, Muhammad; Durigon, Edison Luiz

    2016-10-01

    Bats are notorious reservoirs of genetically-diverse and high-profile pathogens, and are playing crucial roles in the emergence and re-emergence of viruses, both in human and in animals. In this report, we identified and characterized previously unknown and diverse genetic clusters of bat coronaviruses in the Atlantic Forest Biome, Brazil. These results highlight the virus richness of bats and their possible roles in the public health. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Biological productivity, terrigenous influence and noncrustal elements supply to the Central Indian Ocean Basin: Paleoceanography during the past approx. 1 Ma

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Masuzawa, T.; Borole, D.V.; Parthiban, G.; Jauhari, P.; Yamamoto, M.

    A 2 m-long sediment core from the siliceous ooze domain in the Central Indian Ocean Basin (CIOB; 13 degrees 03'S: 74 degrees 44'E; water depth 5099 m) is studied for calcium carbonate, total organic carbon, total nitrogen, biogenic opal, major...

  13. Federal Conservation Units in Brazil: The Situation of Biomes and Regions

    Directory of Open Access Journals (Sweden)

    Eduardo Pacca Luna Mattar

    2018-03-01

    Full Text Available ABSTRACT Federal conservation units (FCU are areas legally established by the government, in order to meet the needs of protection and sustainable exploitation of biodiversity. A way to ensure the efficiency of public management is to systematize data. Therefore, the present study grouped and analyzed public data about FCU. Brazil has 309 federal conservation units, which represent 9.06% of the national territory and 45305 residents households. The Northern Region covers 84.80% of these families and 79.20% of its area belongs to FCU. The Amazônia biome has 14.57% of its territory occupied by FCU; on the other hand, Pantanal has only 0.98% of its area protected. There is a higher concentration of public agents in the FCU of the Southeastern region and in the Mata Atlântica biome. The analysis of this information reveals significant differences between the biomes and the federation units, a fact that reflects the importance of the organization of public data.

  14. Convergence in the temperature response of leaf respiration across biomes and plant functional types.

    Science.gov (United States)

    Heskel, Mary A; O'Sullivan, Odhran S; Reich, Peter B; Tjoelker, Mark G; Weerasinghe, Lasantha K; Penillard, Aurore; Egerton, John J G; Creek, Danielle; Bloomfield, Keith J; Xiang, Jen; Sinca, Felipe; Stangl, Zsofia R; Martinez-de la Torre, Alberto; Griffin, Kevin L; Huntingford, Chris; Hurry, Vaughan; Meir, Patrick; Turnbull, Matthew H; Atkin, Owen K

    2016-04-05

    Plant respiration constitutes a massive carbon flux to the atmosphere, and a major control on the evolution of the global carbon cycle. It therefore has the potential to modulate levels of climate change due to the human burning of fossil fuels. Neither current physiological nor terrestrial biosphere models adequately describe its short-term temperature response, and even minor differences in the shape of the response curve can significantly impact estimates of ecosystem carbon release and/or storage. Given this, it is critical to establish whether there are predictable patterns in the shape of the respiration-temperature response curve, and thus in the intrinsic temperature sensitivity of respiration across the globe. Analyzing measurements in a comprehensive database for 231 species spanning 7 biomes, we demonstrate that temperature-dependent increases in leaf respiration do not follow a commonly used exponential function. Instead, we find a decelerating function as leaves warm, reflecting a declining sensitivity to higher temperatures that is remarkably uniform across all biomes and plant functional types. Such convergence in the temperature sensitivity of leaf respiration suggests that there are universally applicable controls on the temperature response of plant energy metabolism, such that a single new function can predict the temperature dependence of leaf respiration for global vegetation. This simple function enables straightforward description of plant respiration in the land-surface components of coupled earth system models. Our cross-biome analyses shows significant implications for such fluxes in cold climates, generally projecting lower values compared with previous estimates.

  15. Intrinsic climate dependency of ecosystem light and water-use-efficiencies across Australian biomes

    International Nuclear Information System (INIS)

    Shi, Hao; Li, Longhui; Eamus, Derek; Cleverly, James; Huete, Alfredo; Yu, Qiang; Beringer, Jason; Van Gorsel, Eva; Hutley, Lindsay

    2014-01-01

    The sensitivity of ecosystem gross primary production (GPP) to availability of water and photosynthetically active radiation (PAR) differs among biomes. Here we investigated variations of ecosystem light-use-efficiency (eLUE: GPP/PAR) and water-use-efficiency (eWUE: GPP/evapotranspiration) among seven Australian eddy covariance sites with differing annual precipitation, species composition and temperature. Changes to both eLUE and eWUE were primarily correlated with atmospheric vapor pressure deficit (VPD) at multiple temporal scales across biomes, with minor additional correlations observed with soil moisture and temperature. The effects of leaf area index on eLUE and eWUE were also relatively weak compared to VPD, indicating an intrinsic dependency of eLUE and eWUE on climate. Additionally, eLUE and eWUE were statistically different for biomes between summer and winter, except eWUE for savannas and the grassland. These findings will improve our understanding of how light- and water-use traits in Australian ecosystems may respond to climate change. (letter)

  16. Seasonal patterns of horse fly richness and abundance in the Pampa biome of southern Brazil.

    Science.gov (United States)

    Krüger, Rodrigo Ferreira; Krolow, Tiago Kütter

    2015-12-01

    Fluctuations in seasonal patterns of horse fly populations were examined in rainforests of tropical South America, where the climate is seasonal. These patterns were evaluated with robust analytical models rather than identifying the main factors that influenced the fluctuations. We examined the seasonality of populations of horse flies in fields and lowland areas of the Pampa biome of southern Brazil with generalized linear models. We also investigated the diversity of these flies and the sampling effort of Malaise traps in this biome over two years. All of the 29 species had clear seasonality with regard to occurrence and abundance, but only seven species were identified as being influenced by temperature and humidity. The sampling was sufficient and the estimated diversity was 10% more than observed. Seasonal trends were synchronized across species and the populations were most abundant between September and March and nearly zero in other months. While previous studies demonstrated that seasonal patterns in population fluctuations are correlated with climatic conditions in horse fly assemblages in South America rainforests, we show a clear effect of each factor on richness and abundance and the seasonality in the prevalence of horse fly assemblages in localities of the Pampa biome. © 2015 The Society for Vector Ecology.

  17. The future distribution of the savannah biome: model-based and biogeographic contingency.

    Science.gov (United States)

    Moncrieff, Glenn R; Scheiter, Simon; Langan, Liam; Trabucco, Antonio; Higgins, Steven I

    2016-09-19

    The extent of the savannah biome is expected to be profoundly altered by climatic change and increasing atmospheric CO2 concentrations. Contrasting projections are given when using different modelling approaches to estimate future distributions. Furthermore, biogeographic variation within savannahs in plant function and structure is expected to lead to divergent responses to global change. Hence the use of a single model with a single savannah tree type will likely lead to biased projections. Here we compare and contrast projections of South American, African and Australian savannah distributions from the physiologically based Thornley transport resistance statistical distribution model (TTR-SDM)-and three versions of a dynamic vegetation model (DVM) designed and parametrized separately for specific continents. We show that attempting to extrapolate any continent-specific model globally biases projections. By 2070, all DVMs generally project a decrease in the extent of savannahs at their boundary with forests, whereas the TTR-SDM projects a decrease in savannahs at their boundary with aridlands and grasslands. This difference is driven by forest and woodland expansion in response to rising atmospheric CO2 concentrations in DVMs, unaccounted for by the TTR-SDM. We suggest that the most suitable models of the savannah biome for future development are individual-based dynamic vegetation models designed for specific biogeographic regions.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'. © 2016 The Author(s).

  18. Plant phylogeny as a window on the evolution of hyperdiversity in the tropical rainforest biome.

    Science.gov (United States)

    Eiserhardt, Wolf L; Couvreur, Thomas L P; Baker, William J

    2017-06-01

    I. II. III. IV. V. VI. VII. VIII. IX. References SUMMARY: Tropical rainforest (TRF) is the most species-rich terrestrial biome on Earth, harbouring just under half of the world's plant species in c. 7% of the land surface. Phylogenetic trees provide important insights into mechanisms underpinning TRF hyperdiversity that are complementary to those obtained from the fossil record. Phylogenetic studies of TRF plant diversity have mainly focused on whether this biome is an evolutionary 'cradle' or 'museum', emphasizing speciation and extinction rates. However, other explanations, such as biome age, immigration and ecological limits, must also be considered. We present a conceptual framework for addressing the drivers of TRF diversity, and review plant studies that have tested them with phylogenetic data. Although surprisingly few in number, these studies point to old age of TRF, low extinction and high speciation rates as credible drivers of TRF hyperdiversity. There is less evidence for immigration and ecological limits, but these cannot be dismissed owing to the limited number of studies. Rapid methodological developments in DNA sequencing, macroevolutionary analysis and the integration of phylogenetics with other disciplines may improve our grasp of TRF hyperdiversity in the future. However, such advances are critically dependent on fundamental systematic research, yielding numerous, additional, well-sampled phylogenies of TRF lineages. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  19. Reimplementation of the Biome-BGC model to simulate successional change.

    Science.gov (United States)

    Bond-Lamberty, Ben; Gower, Stith T; Ahl, Douglas E; Thornton, Peter E

    2005-04-01

    Biogeochemical process models are increasingly employed to simulate current and future forest dynamics, but most simulate only a single canopy type. This limitation means that mixed stands, canopy succession and understory dynamics cannot be modeled, severe handicaps in many forests. The goals of this study were to develop a version of Biome-BGC that supported multiple, interacting vegetation types, and to assess its performance and limitations by comparing modeled results to published data from a 150-year boreal black spruce (Picea mariana (Mill.) BSP) chronosequence in northern Manitoba, Canada. Model data structures and logic were modified to support an arbitrary number of interacting vegetation types; an explicit height calculation was necessary to prioritize radiation and precipitation interception. Two vegetation types, evergreen needle-leaf and deciduous broadleaf, were modeled based on site-specific meteorological and physiological data. The new version of Biome-BGC reliably simulated observed changes in leaf area, net primary production and carbon stocks, and should be useful for modeling the dynamics of mixed-species stands and ecological succession. We discuss the strengths and limitations of Biome-BGC for this application, and note areas in which further work is necessary for reliable simulation of boreal biogeochemical cycling at a landscape scale.

  20. Modelling the impacts of reoccurring fires in tropical savannahs using Biome-BGC.

    Science.gov (United States)

    Fletcher, Charlotte; Petritsch, Richard; Pietsch, Stephan

    2010-05-01

    Fires are a dominant feature of tropical savannahs and have occurred throughout history by natural as well as human-induced means. These fires have a profound influence on the landscape in terms of flux dynamics and vegetative species composition. This study attempts to understand the impacts of fire regimes on flux dynamics and vegetation composition in savannahs using the Biome-BGC model. The Batéké Plateau, Gabon - an area of savannah grasslands in the Congo basin, serves as a case-study. To achieve model validation for savannahs, data sets from stands with differing levels of past burning are used. It is hypothesised that the field measurements from those stands with lower-levels of past burning will correlate with the Biome-BGC model output, meaning that the model is validated for the savannah excluding fire regimes. However, in reality, fire is frequent in the savannah. Data on past fire events are available from the Moderate Resolution Imaging Spectroradiometer (MODIS) to provide the fire regimes of the model. As the field data-driven measurements of the burnt stands are influenced by fire in the savannah, this will therefore result in a Biome-BGC model validated for the impacts of fire on savannah ecology. The validated model can then be used to predict the savannah's flux dynamics under the fire scenarios expected with climate and/or human impact change.

  1. Development of the BIOME-BGC model for the simulation of managed Moso bamboo forest ecosystems.

    Science.gov (United States)

    Mao, Fangjie; Li, Pingheng; Zhou, Guomo; Du, Huaqiang; Xu, Xiaojun; Shi, Yongjun; Mo, Lufeng; Zhou, Yufeng; Tu, Guoqing

    2016-05-01

    Numerical models are the most appropriate instrument for the analysis of the carbon balance of terrestrial ecosystems and their interactions with changing environmental conditions. The process-based model BIOME-BGC is widely used in simulation of carbon balance within vegetation, litter and soil of unmanaged ecosystems. For Moso bamboo forests, however, simulations with BIOME-BGC are inaccurate in terms of the growing season and the carbon allocation, due to the oversimplified representation of phenology. Our aim was to improve the applicability of BIOME-BGC for managed Moso bamboo forest ecosystem by implementing several new modules, including phenology, carbon allocation, and management. Instead of the simple phenology and carbon allocation representations in the original version, a periodic Moso bamboo phenology and carbon allocation module was implemented, which can handle the processes of Moso bamboo shooting and high growth during "on-year" and "off-year". Four management modules (digging bamboo shoots, selective cutting, obtruncation, fertilization) were integrated in order to quantify the functioning of managed ecosystems. The improved model was calibrated and validated using eddy covariance measurement data collected at a managed Moso bamboo forest site (Anji) during 2011-2013 years. As a result of these developments and calibrations, the performance of the model was substantially improved. Regarding the measured and modeled fluxes (gross primary production, total ecosystem respiration, net ecosystem exchange), relative errors were decreased by 42.23%, 103.02% and 18.67%, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Beyond the climate envelope: using trait filtering models to predict biome boundaries from plant physiology.

    Science.gov (United States)

    Fisher, R.; Hoffmann, W. A.; Muszala, S.

    2014-12-01

    The introduction of second-generation dynamic vegetation models - which simulate the distribution of light resources between plant types along the vertical canopy profile, and therefore facilitate the representation of plant competition explicitly - is a large increase in the complexity and fidelity with which the terrestrial biosphere is abstracted into Earth System Models. In this new class of model, biome boundaries are predicted as the emergent properties of plant physiology, and are therefore sensitive to the high-dimensional parameterizations of plant functional traits. These new approaches offer the facility to quantitatively test ecophysiological hypotheses of plant distribution at large scales, a field which remains surprisingly under-developed. Here we describe experiments conducted with the Community Land Model Ecosystem Demography component, CLM(ED), in which we reduce the complexity of the problem by testing how individual plant functional trait changes to control the location of biome boundaries between functional types. Specifically, we investigate which physiological trade-offs determine the boundary between frequently burned savanna and forest biomes, and attempt to distinguish how each strategic life-history trade-off (carbon storage, bark investment, re-sprouting strategy) contributes towards the maintenance of sharp geographical gradients between fire adapted and typically inflammable closed canopy ecosystems. This study forms part of the planning for a model-inspired fire manipulation experiment at the cerrado-forest boundary in South-Eastern Brazil, and the results will be used to guide future data-collection and analysis strategies.

  3. ANTIBACTERIAL POTENTIAL OF NATIVE PLANTS FROM THE CAATINGA BIOME AGAINST Staphylococcus spp. ISOLATES FROM SMALL RUMINANTS WITH MASTITIS

    OpenAIRE

    PEIXOTO, RODOLFO DE MORAES; SILVA, WELLINGTON ERASMO LIMA E; ALMEIDA, JACKSON ROBERTO GUEDES SILVA; BRANCO, ALEXSANDRO; COSTA, MATEUS MATIUZZI DA

    2016-01-01

    ABSTRACT The aim of the present study is to assess the antibacterial potential of plants from the Caatinga biome of the semi-arid region of Pernambuco, against Staphylococcus spp. isolates from cases of subclinical mastitis in small ruminants, such as goats and ewes. Ethanolic extracts of the following plants from the Caatinga biome were used: Encholirium spectabile Mart., Bromelia laciniosa Mart., Neoglaziovia variegata Mez., Amburana cearensis (Fr. Allem.) A. C. Smith, Hymenaea martiana Hay...

  4. Modelling the carbon budget of intensive forest monitoring sites in Germany using the simulation model BIOME-BGC

    OpenAIRE

    Jochheim, H.; Puhlmann, M.; Beese, F.; Berthold, D.; Einert, P.; Kallweit, R.; Konopatzky, A.; Meesenburg, H.; Meiwes, K.-J.; Raspe, S.; Schulte-Bisping, H.; Schulz, C.

    2008-01-01

    It is shown that by calibrating the simulation model BIOME-BGC with mandatory and optional Level II data, within the ICP Forest programme, a well-founded calculation of the carbon budget of forest stands is achievable and, based on succeeded calibration, the modified BIOME-BGC model is a useful tool to assess the effect of climate change on forest ecosystems. peerReviewed

  5. Evolutionary history of a keystone pollinator parallels the biome occupancy of angiosperms in the Greater Cape Floristic Region.

    Science.gov (United States)

    de Jager, Marinus L; Ellis, Allan G

    2017-02-01

    The Greater Cape Floristic Region (GCFR) in South Africa has been extensively investigated for its phenomenal angiosperm diversity. A key emergent pattern is the occurrence of older plant lineages in the southern Fynbos biome and younger lineages in the northern Succulent Karoo biome. We know practically nothing, however, about the evolutionary history of the animals that pollinate this often highly-specialized flora. In this study, we explore the evolutionary history of an important GCFR fly pollinator, Megapalpus capensis, and ask whether it exhibits broadly congruent genetic structuring and timing of diversification to flowering plants within these biomes. We find that the oldest M. capensis lineages originated in Fynbos during the Miocene, while younger Succulent Karoo lineages diverged in the Pliocene and correspond to the proposed age of this recent biome. A strong signature of population expansion is also recovered for flies in this arid biome, consistent with recent colonization. Our first investigation into the evolutionary history of GCFR pollinators thus supports a recent origin of the SK biome, as inferred from angiosperm phylogenies, and suggests that plants and pollinators may have co-diverged within this remarkable area. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. A spatial assessment of Brassica napus gene flow potential to wild and weedy relatives in the Fynbos Biome

    Directory of Open Access Journals (Sweden)

    J. M. Kalwij

    2010-01-01

    Full Text Available Gene flow between related plant species, and between transgenic and non-transgenic crop varieties, may be considered a form of biological invasion. Brassica napus (oilseed rape or canola and its relatives are well known for intra- and inter-specific gene flow, hybridisation and weediness. Gene flow associated with B. napus poses a potential ecological risk in the Fynbos Biome of South Africa, because of the existence of both naturalised (alien, weedy and native relatives in this region. This risk is particularly pertinent given the proposed use of B. napus for biofuel and the potential future introduction of herbicide-tolerant transgenic B. napus. Here we quantify the presence and co-occurrence of B. napus and its wild and weedy relatives in the Fynbos Biome, as a first step in the ecological risk assessment for this crop. Several alien and at least one native relative of B. napus were found to be prevalent in the region, and to be spatially congruent with B. napus fields. The first requirement for potential gene flow to occur has thus been met. In addition, a number of these species have elsewhere been found to be reproductively compatible with B. napus. Further assessment of the potential ecological risks associated with B. napus in South Africa is constrained by uncertainties in the phylogeny of the Brassicaceae, difficulties with morphology-based identification, and poor knowledge of the biology of several of the species involved, particularly under South African conditions.

  7. Biological oceanography, biogeochemical cycles, and pelagic ecosystem functioning of the east-central South Pacific Gyre: focus on Easter Island and Salas y Gómez Island

    OpenAIRE

    Von Dassow , Peter; Collado-Fabbri , Silvana

    2014-01-01

    International audience; The Exclusive Economic Zone of Chile defined by Easter Island and Salas y Gómez Island is in the South Pacific Subtropical Gyre (SPSG), putting it at the center of the most oligotrophic and biomass poor waters in the world. Only 10 biological oceanographic expeditions have entered this zone in 105 years (1905-2010). We review key aspects of the plankton ecosystem and biogeochemical function relevant for the understanding of and conservation planning for marine environm...

  8. BioCichlid: central dogma-based 3D visualization system of time-course microarray data on a hierarchical biological network.

    Science.gov (United States)

    Ishiwata, Ryosuke R; Morioka, Masaki S; Ogishima, Soichi; Tanaka, Hiroshi

    2009-02-15

    BioCichlid is a 3D visualization system of time-course microarray data on molecular networks, aiming at interpretation of gene expression data by transcriptional relationships based on the central dogma with physical and genetic interactions. BioCichlid visualizes both physical (protein) and genetic (regulatory) network layers, and provides animation of time-course gene expression data on the genetic network layer. Transcriptional regulations are represented to bridge the physical network (transcription factors) and genetic network (regulated genes) layers, thus integrating promoter analysis into the pathway mapping. BioCichlid enhances the interpretation of microarray data and allows for revealing the underlying mechanisms causing differential gene expressions. BioCichlid is freely available and can be accessed at http://newton.tmd.ac.jp/. Source codes for both biocichlid server and client are also available.

  9. Morphofunctional diversity of equine of varied genetic compositions raised in the Pantanal biome of Brazil.

    Science.gov (United States)

    de Rezende, Marcos Paulo Gonçalves; de Souza, Julio Cesar; Carneiro, Paulo Luiz Souza; Bozzi, Riccardo; Jardim, Rodrigo Jose Delgado; Malhado, Carlos Henrique Mendes

    2018-06-01

    Evaluating phenotypic diversity makes it possible to identify discrepancies in aptitudes among animals of different genetic bases, which is an indicator of adaptive or selective differences between populations. The objective of this work was to evaluate the morphofunctional diversity of 452 male and female adult equines (Arabian, Quarter Mile, Pantaneiro, and Criollo breeds, and undefined crossbreeds of horses and mules) raised in the Pantanal biome (Brazil). Linear measurements were performed to estimate conformation indexes. Initially, a discriminant analysis was performed, regardless of the animal's size, followed by factor analysis. The factors were characterized and used as new variables. The diversity among equines and their relationship with the factors were evaluated using multivariate analysis. The factors were classified according to their decreasing importance: balance, rusticity, and robustness for the measurement factors; and load, ability, conformation, and equilibrium for the index factors. The genetic groups of equines have well-defined morphofunctional characteristics. The main differences are based on the rusticity and ability typologies in relation to those based on performance. Equines introduced to the Pantanal biome presented a more robust and compact body with good conformation. As a result, these horses may have superior athletic performance during equestrian activities when compared to the Pantaneiro local breed. However, this biotype may represent less rusticity (less adaptive capacity). Therefore, the regional breed can be equal or better in equestrian activities than breeds introduced to the Pantanal biome. Thus, breeders may cross horses from local breeds as an alternative to those introduced. Undefined crossbred male equines presented a different profile from the Pantaneiro breed, which may indicate little use of crossbreeds in breeding.

  10. Identification of priority conservation areas and potential corridors for jaguars in the Caatinga biome, Brazil.

    Science.gov (United States)

    Morato, Ronaldo Gonçalves; Ferraz, Katia Maria Paschoaletto Micchi de Barros; de Paula, Rogério Cunha; de Campos, Cláudia Bueno

    2014-01-01

    The jaguar, Panthera onca, is a top predator with the extant population found within the Brazilian Caatinga biome now known to be on the brink of extinction. Designing new conservation units and potential corridors are therefore crucial for the long-term survival of the species within the Caatinga biome. Thus, our aims were: 1) to recognize suitable areas for jaguar occurrence, 2) to delineate areas for jaguar conservation (PJCUs), 3) to design corridors among priority areas, and 4) to prioritize PJCUs. A total of 62 points records of jaguar occurrence and 10 potential predictors were analyzed in a GIS environment. A predictive distributional map was obtained using Species Distribution Modeling (SDM) as performed by the Maximum Entropy (Maxent) algorithm. Areas equal to or higher than the median suitability value of 0.595 were selected as of high suitability for jaguar occurrence and named as Priority Jaguar Conservation Units (PJCU). Ten PJCUs with sizes varying from 23.6 km2 to 4,311.0 km2 were identified. Afterwards, we combined the response curve, as generated by SDM, and expert opinions to create a permeability matrix and to identify least cost corridors and buffer zones between each PJCU pair. Connectivity corridors and buffer zone for jaguar movement included an area of 8.884,26 km2 and the total corridor length is about 160.94 km. Prioritizing criteria indicated the PJCU representing c.a. 68.61% of the total PJCU area (PJCU # 1) as of high priority for conservation and connectivity with others PJCUs (PJCUs # 4, 5 and 7) desirable for the long term survival of the species. In conclusion, by using the jaguar as a focal species and combining SDM and expert opinion we were able to create a valid framework for practical conservation actions at the Caatinga biome. The same approach could be used for the conservation of other carnivores.

  11. Identification of priority conservation areas and potential corridors for jaguars in the Caatinga biome, Brazil.

    Directory of Open Access Journals (Sweden)

    Ronaldo Gonçalves Morato

    Full Text Available The jaguar, Panthera onca, is a top predator with the extant population found within the Brazilian Caatinga biome now known to be on the brink of extinction. Designing new conservation units and potential corridors are therefore crucial for the long-term survival of the species within the Caatinga biome. Thus, our aims were: 1 to recognize suitable areas for jaguar occurrence, 2 to delineate areas for jaguar conservation (PJCUs, 3 to design corridors among priority areas, and 4 to prioritize PJCUs. A total of 62 points records of jaguar occurrence and 10 potential predictors were analyzed in a GIS environment. A predictive distributional map was obtained using Species Distribution Modeling (SDM as performed by the Maximum Entropy (Maxent algorithm. Areas equal to or higher than the median suitability value of 0.595 were selected as of high suitability for jaguar occurrence and named as Priority Jaguar Conservation Units (PJCU. Ten PJCUs with sizes varying from 23.6 km2 to 4,311.0 km2 were identified. Afterwards, we combined the response curve, as generated by SDM, and expert opinions to create a permeability matrix and to identify least cost corridors and buffer zones between each PJCU pair. Connectivity corridors and buffer zone for jaguar movement included an area of 8.884,26 km2 and the total corridor length is about 160.94 km. Prioritizing criteria indicated the PJCU representing c.a. 68.61% of the total PJCU area (PJCU # 1 as of high priority for conservation and connectivity with others PJCUs (PJCUs # 4, 5 and 7 desirable for the long term survival of the species. In conclusion, by using the jaguar as a focal species and combining SDM and expert opinion we were able to create a valid framework for practical conservation actions at the Caatinga biome. The same approach could be used for the conservation of other carnivores.

  12. Reactivity continuum modeling of leaf, root, and wood decomposition across biomes

    Science.gov (United States)

    Koehler, Birgit; Tranvik, Lars J.

    2015-07-01

    Large carbon dioxide amounts are released to the atmosphere during organic matter decomposition. Yet the large-scale and long-term regulation of this critical process in global carbon cycling by litter chemistry and climate remains poorly understood. We used reactivity continuum (RC) modeling to analyze the decadal data set of the "Long-term Intersite Decomposition Experiment," in which fine litter and wood decomposition was studied in eight biome types (224 time series). In 32 and 46% of all sites the litter content of the acid-unhydrolyzable residue (AUR, formerly referred to as lignin) and the AUR/nitrogen ratio, respectively, retarded initial decomposition rates. This initial rate-retarding effect generally disappeared within the first year of decomposition, and rate-stimulating effects of nutrients and a rate-retarding effect of the carbon/nitrogen ratio became more prevalent. For needles and leaves/grasses, the influence of climate on decomposition decreased over time. For fine roots, the climatic influence was initially smaller but increased toward later-stage decomposition. The climate decomposition index was the strongest climatic predictor of decomposition. The similar variability in initial decomposition rates across litter categories as across biome types suggested that future changes in decomposition may be dominated by warming-induced changes in plant community composition. In general, the RC model parameters successfully predicted independent decomposition data for the different litter-biome combinations (196 time series). We argue that parameterization of large-scale decomposition models with RC model parameters, as opposed to the currently common discrete multiexponential models, could significantly improve their mechanistic foundation and predictive accuracy across climate zones and litter categories.

  13. Clonality analysis of lymphoid proliferations using the BIOMED-2 clonality assays: a single institution experience

    Science.gov (United States)

    Kokovic, Ira; Novakovic, Barbara Jezersek; Cerkovnik, Petra; Novakovic, Srdjan

    2014-01-01

    Background Clonality determination in patients with lymphoproliferative disorders can improve the final diagnosis. The aim of our study was to evaluate the applicative value of standardized BIOMED-2 gene clonality assay protocols for the analysis of clonality of lymphocytes in a group of different lymphoid proliferations. Materials and methods. With this purpose, 121 specimens from 91 patients with suspected lymphoproliferations submitted for routine diagnostics from January to December 2011 were retrospectively analyzed. According to the final diagnosis, our series comprised 32 cases of B-cell lymphomas, 38 cases of non-Hodgkin’s T-cell lymphomas and 51 cases of reactive lymphoid proliferations. Clonality testing was performed using the BIOMED-2 clonality assays. Results The determined sensitivity of the TCR assay was 91.9%, while the sensitivity of the IGH assay was 74.2%. The determined specificity of the IGH assay was 73.3% in the group of lymphomas and 87.2% in the group of reactive lesions. The determined specificity of the TCR assay was 62.5% in the group of lymphomas and 54.3% in the group of reactive lesions. Conclusions In the present study, we confirmed the utility of standardized BIOMED-2 clonality assays for the detection of clonality in a routine diagnostical setting of non-Hodgkin’s lymphomas. Reactions for the detection of the complete IGH rearrangements and reactions for the detection of the TCR rearrangements are a good choice for clonality testing of a wide range of lymphoid proliferations and specimen types while the reactions for the detection of incomplete IGH rearrangements have not shown any additional diagnostic value. PMID:24991205

  14. Global soil-climate-biome diagram: linking soil properties to climate and biota

    Science.gov (United States)

    Zhao, X.; Yang, Y.; Fang, J.

    2017-12-01

    As a critical component of the Earth system, soils interact strongly with both climate and biota and provide fundamental ecosystem services that maintain food, climate, and human security. Despite significant progress in digital soil mapping techniques and the rapidly growing quantity of observed soil information, quantitative linkages between soil properties, climate and biota at the global scale remain unclear. By compiling a large global soil database, we mapped seven major soil properties (bulk density [BD]; sand, silt and clay fractions; soil pH; soil organic carbon [SOC] density [SOCD]; and soil total nitrogen [STN] density [STND]) based on machine learning algorithms (regional random forest [RF] model) and quantitatively assessed the linkage between soil properties, climate and biota at the global scale. Our results demonstrated a global soil-climate-biome diagram, which improves our understanding of the strong correspondence between soils, climate and biomes. Soil pH decreased with greater mean annual precipitation (MAP) and lower mean annual temperature (MAT), and the critical MAP for the transition from alkaline to acidic soil pH decreased with decreasing MAT. Specifically, the critical MAP ranged from 400-500 mm when the MAT exceeded 10 °C but could decrease to 50-100 mm when the MAT was approximately 0 °C. SOCD and STND were tightly linked; both increased in accordance with lower MAT and higher MAP across terrestrial biomes. Global stocks of SOC and STN were estimated to be 788 ± 39.4 Pg (1015 g, or billion tons) and 63 ± 3.3 Pg in the upper 30-cm soil layer, respectively, but these values increased to 1654 ± 94.5 Pg and 133 ± 7.8 Pg in the upper 100-cm soil layer, respectively. These results reveal quantitative linkages between soil properties, climate and biota at the global scale, suggesting co-evolution of the soil, climate and biota under conditions of global environmental change.

  15. Clinical phenotypes and the biological parameters of Congolese patients suffering from sickle cell anemia: A first report from Central Africa.

    Science.gov (United States)

    Mikobi, Tite M; Lukusa Tshilobo, Prosper; Aloni, Michel N; Akilimali, Pierre Z; Mvumbi-Lelo, Georges; Mbuyi-Muamba, Jean Marie

    2017-11-01

    The influence of phenotype on the clinical course and laboratory features of sickle cell anemia (SCA) is rarely described in sub-Saharan Africa. A cross-sectional study was conducted in Kinshasa. A clinical phenotype score was built up. The following definitions were applied: asymptomatic clinical phenotype (ACP; score≤5), moderate clinical phenotype (MCP; score between 6 and 15), and severe clinical phenotype (SCP; score≥16). ANOVA test were used to compare differences among categorical variables. We have studied 140 patients. The mean body mass index (BMI) value of three groups was lower (Sickle cell patients with ACP have a high mean steady-state hemoglobin concentration compared to those with MCP and SCP (Psickle cell anemia clinical and biological variability in our midst. © 2017 Wiley Periodicals, Inc.

  16. Aspectos biométricos y reproductivos de Boquichico Prochilodus nigricans Agassiz, 1829 (Pisces: Prochilodontidae en Ucayali, Perú

    Directory of Open Access Journals (Sweden)

    José C. Riofrío Q.

    2013-06-01

    Full Text Available El conocimiento de la biología y pesquería de una especie explotada es esencial para un manejo racional y una producción sostenida. De febrero a diciembre de 1994 se colectó información de una de las especies más importantes por los volúmenes de desembarque en Ucayali, el boquichico (Prochilodus nigricans. Se analizaron aspectos biométricos (relación longitud total - peso total: LTPT y reproductivos (proporción por sexos, época de reproducción, tallas de madurez de esta especie. La relación LT-PT no mostró diferencias significativas entre las regresiones de machos y hembras (análisis de variancias residual F0,05 proponiéndose el empleo de una ecuación conjunta para la especie de la forma PT = 0,0211 LT 2,8592. La proporción sexual total no mostró diferencias significativas (χ 2 0,05 al asumir una relación 1:1. El análisis de la progresión de los estadios de madurez confirma la reproducción durante la temporada de elevación del nivel del río Ucayali (octubre-enero. La talla de madurez calculada para los machos fue de 24,5 cm y para las hembras de 26.1 cm, recomendándose esta última para el manejo de la pesquería.

  17. Anthropization on the Cerrado biome in the Brazilian Uruçuí-Una Ecological Station estimated from orbital images.

    Science.gov (United States)

    Pereira, A C; Gama, V F

    2010-11-01

    In this study we analysed the dynamics of deforestation and burnings during the dry seasons from 2003 to 2008 in the Uruçuí-Una Ecological Station (UUES) and its buffer zone, located in the Cerrado biome of the southwest of Piauí, a Brazil's State, based on images from the orbital sensors CCD/CBERS-2 and TM/Landsat-5. Two dates from each of the years were interpreted and analysed: one in the middle of the dry season and one at the end. The deforested areas were expanded through the period analysed and were larger in the buffer zone, suggesting a relative protection of the UUES. New cut-offs were predictable because of the early opening of roads that would become their limits. The burning scars were larger at the end of the dry season as a consequence of the management and implementation of agricultures and pastures. In 2004 and 2007 these scars were larger probably because of the increase of dry phytomass that every three years is big enough to spread the fire originated in the anthropogenic burnings through the native vegetation. This scenario reaffirms the need for: stronger enforcement in order to stop anthropisation in the UUES and a management plan, absent for this unit so far. These proceedings are urgent also because the UUES is located in one of the most preserved regions of the Cerrado and controversially where intense anthropisation in ongoing, which stresses the lack, need and urgency of biological conservation proceedings for the Piauí's southeastern Cerrado.

  18. Anthropization on the Cerrado biome in the Brazilian Uruçuí-Una Ecological Station estimated from orbital images

    Directory of Open Access Journals (Sweden)

    AC. Pereira

    Full Text Available In this study we analysed the dynamics of deforestation and burnings during the dry seasons from 2003 to 2008 in the Uruçuí-Una Ecological Station (UUES and its buffer zone, located in the Cerrado biome of the southwest of Piauí, a Brazil's State, based on images from the orbital sensors CCD/CBERS-2 and TM/Landsat-5. Two dates from each of the years were interpreted and analysed: one in the middle of the dry season and one at the end. The deforested areas were expanded through the period analysed and were larger in the buffer zone, suggesting a relative protection of the UUES. New cut-offs were predictable because of the early opening of roads that would become their limits. The burning scars were larger at the end of the dry season as a consequence of the management and implementation of agricultures and pastures. In 2004 and 2007 these scars were larger probably because of the increase of dry phytomass that every three years is big enough to spread the fire originated in the anthropogenic burnings through the native vegetation. This scenario reaffirms the need for: stronger enforcement in order to stop anthropisation in the UUES and a management plan, absent for this unit so far. These proceedings are urgent also because the UUES is located in one of the most preserved regions of the Cerrado and controversially where intense anthropisation in ongoing, which stresses the lack, need and urgency of biological conservation proceedings for the Piauí's southeastern Cerrado.

  19. Marine litter in an EBSA (Ecologically or Biologically Significant Area) of the central Mediterranean Sea: Abundance, composition, impact on benthic species and basis for monitoring entanglement.

    Science.gov (United States)

    Consoli, Pierpaolo; Andaloro, Franco; Altobelli, Chiara; Battaglia, Pietro; Campagnuolo, Silvana; Canese, Simonepietro; Castriota, Luca; Cillari, Tiziana; Falautano, Manuela; Pedà, Cristina; Perzia, Patrizia; Sinopoli, Mauro; Vivona, Pietro; Scotti, Gianfranco; Esposito, Valentina; Galgani, Francois; Romeo, Teresa

    2018-05-01

    Marine litter is commonly observed everywhere in the ocean. In this study, we analyzed 17 km of video footage, collected by a Remotely Operated Vehicle (ROV) at depths ranging between 20 and 220 m, during 19 transects performed on the rocky banks of the Straits of Sicily. Recently, the Contracting Parties of the Convention on Biological Diversity (CBD) recognized this site as an Ecologically or Biologically Significant Area (EBSA). The research aim was to quantify the abundance of marine litter and its impact on benthic fauna. Litter density ranged from 0 items/100 m 2 to 14.02 items/100 m 2 with a mean (±standard error) of 2.13 (±0.84) items/100 m 2 . The observed average density was higher (5.2 items/100 m 2 ) at depths >100 m than at shallower depths (fishing lines contributed to 98.07% of the overall litter density, then representing the dominant source of marine debris. Litter interactions with fauna were frequently observed, with 30% of litter causing "entanglement/coverage" and 15% causing damage to sessile fauna. A total of 16 species showed interaction (entanglement/coverage or damage) with litter items and 12 of these are species of conservation concern according to international directives and agreements (CITES, Berne Convention, Habitat Directive, SPA/BD Protocol, IUCN Red List); we also observed 7 priority habitats of the SPA/BD Protocol. This research will support the implementation of monitoring "Harm" as recommended by the UN Environment/MAP Regional Plan on Marine Litter Management in the Mediterranean, and the Marine Strategy Framework Directive (MSFD). The institution of a SPAMI in the investigated area could represent a good management action for the protection of this hotspot of biodiversity and to achieve a Good Environmental Status (GES) for the marine environment by 2020, under the MSFD. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Biological oceanography, biogeochemical cycles, and pelagic ecosystem functioning of the east-central South Pacific Gyre: focus on Easter Island and Salas y Gómez Island

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    Peter von Dassow

    2014-10-01

    Full Text Available The Exclusive Economic Zone of Chile defined by Easter Island and Salas y Gómez Island is in the South Pacific Sub-tropical Gyre (SPSG, putting it at the center of the most oligotrophic and biomass poor waters in the world. Only 10 biological oceanographic expeditions have entered this zone in 105 years (19052010. We review key aspects of the plankton ecosystem and biogeochemical function relevant for the understanding of and conservation planning for marine environments. Plankton production is limited by lack of dissolved inorganic fixed nitrogen, not phosphorous. Higher organic nitrogen levels might be biologically unavailable. Short-term experiments suggested iron is not limiting, yet iron still likely limits nitrogen fixation, and thus production, at longer time scales, as the presence of nitrogen-fixers is exceptionally low compared to other ocean gyres. Plankton function is dominated by the smallest unicellular organisms, picoplankton (<3 μm in diameter. The SPSG represents a center of high biodiversity for picoplankton, as well as heterotrophic organisms such as tinntinids, siphonophores, and possibly amphipods, although data for key zooplankton, such as copepods, are lacking. Many groups exhibit negative relationships between diversity and total plankton biomass. High diversity might result from dispersal from a very large metacommunity and minimal competition within functional groups. Whether an island-mass effect causes a real or apparent increase in plankton biomass around Easter Island must be confirmed by high-resolution sampling in situ. Long-term threats to the planktonic ecosystem may include climate change-enhanced ocean stratification and plastic marine debris accumulation. Finally, priorities for future research are highlighted.

  1. Biomímesis: una propuesta ética y técnica para reorientar la ingeniería por los senderos de la sustentabilidad

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    Nicolás Jiménez Iguarán

    2016-01-01

    Full Text Available Nos encontramos en lo que el intelectual español Jorge Riechmann denomina “el siglo de la gran prueba”. La actual crisis ambiental, cuyos síntomas no dejan de aparecer, nos impone retos en todos los niveles de nuestra vida. El presente trabajo tiene el propósito de explorar las potencialidades que tiene la ingeniería para superar esta crisis (o “prueba”, a la luz de la categoría biomímesis. Para esto, partimos de una reflexión central sobre la correspondencia entre el saber técnico ingenieril, los límites de la naturaleza y la noción de progreso para, a partir de ella, realizar una crítica propositiva a la ingeniería e inferir algunos elementos éticos que encaminen su desarrollo. Como ciencia aplicada, la ingeniería forma parte de nuestras vidas así no seamos plenamente conscientes de ello. En su desarrollo y evolución ha contribuido a producir sobrecargas significativas en la biósfera. La ética ambiental ha venido insistiendo, durante más de cinco décadas, en la necesidad de reconducir nuestra civilización hacia técnicas aplicadas que aprendan de la naturaleza en lugar de degradarla. La biomímesis, al recordar que los resultados de la ingeniería deben estar asociados a un objetivo social colectivo, se presenta como un camino para superar esta compleja realidad.

  2. Sensitivity Analysis of Biome-Bgc Model for Dry Tropical Forests of Vindhyan Highlands, India

    Science.gov (United States)

    Kumar, M.; Raghubanshi, A. S.

    2011-08-01

    A process-based model BIOME-BGC was run for sensitivity analysis to see the effect of ecophysiological parameters on net primary production (NPP) of dry tropical forest of India. The sensitivity test reveals that the forest NPP was highly sensitive to the following ecophysiological parameters: Canopy light extinction coefficient (k), Canopy average specific leaf area (SLA), New stem C : New leaf C (SC:LC), Maximum stomatal conductance (gs,max), C:N of fine roots (C:Nfr), All-sided to projected leaf area ratio and Canopy water interception coefficient (Wint). Therefore, these parameters need more precision and attention during estimation and observation in the field studies.

  3. SENSITIVITY ANALYSIS OF BIOME-BGC MODEL FOR DRY TROPICAL FORESTS OF VINDHYAN HIGHLANDS, INDIA

    OpenAIRE

    M. Kumar; A. S. Raghubanshi

    2012-01-01

    A process-based model BIOME-BGC was run for sensitivity analysis to see the effect of ecophysiological parameters on net primary production (NPP) of dry tropical forest of India. The sensitivity test reveals that the forest NPP was highly sensitive to the following ecophysiological parameters: Canopy light extinction coefficient (k), Canopy average specific leaf area (SLA), New stem C : New leaf C (SC:LC), Maximum stomatal conductance (gs,max), C:N of fine roots (C:Nfr), All-sided to...

  4. Characterizing forest carbon stocks at tropical biome and landscape level in Mount Apo National Park, Philippines

    Science.gov (United States)

    Rubas, L. C.

    2012-12-01

    Forest resources sequester and store carbon, and serve as a natural brake on climate change. In the tropics, the largest source of greenhouse emission is from deforestation and forest degradation (Gibbs et al 2007). This paper attempts to compile sixty (60) existing studies on using remote sensing to measure key environmental forest indicators at two levels of scales: biome and landscape level. At the tropical forest biome level, there is not as much remote sensing studies that have been done as compared to other forest biomes. Also, existing studies on tropical Asia is still sparse compared to other tropical regions in Latin America and Africa. Biomass map is also produced for the tropical biome using keyhole macro language (KML) which is projected on Google Earth. The compiled studies showed there are four indicators being measured using remote sensors in tropical forest. These are biomass, landcover classification, deforestation and cloud cover. The landscape level will focus on Mount Apo National Park in the Philippines which is encompassing a total area of 54,974.87 hectares. It is one of the ten priority sites targeted in the World Bank-assisted Biodiversity Conservation Program. This park serves as the major watershed for the three provinces with 19 major rivers emanating from the montane formations. Only a small fraction of the natural forest that once covered the country remains. In spite of different policies that aim to reduce logging recent commercial deforestation, illegal logging and agricultural expansion pose an important threat to the remaining forest areas. In some locations in the country, these hotspots of deforestation overlap with the protected areas (Verburg et al 2006). The study site was clipped using ArcGIS from the forest biomass carbon density map produced by Gibbs and Brown (2007). Characterization on this national park using vegetation density, elevation, slope, land cover and precipitation will be conducted to determine factors that

  5. Extensiones biométricas para bases de datos objeto- relacionales

    OpenAIRE

    Miranda, Ernesto; Ruíz, Silvia; Aguirre, Juan José; Herlein, Mauro; Etchart, Graciela; Alvez, Carlos E.

    2017-01-01

    La autenticación de personas basadas en rasgos biométricos se ha vuelto muy popular en los últimos años como consecuencia de la baja en los costos de los sensores requeridos, su inclusión en dispositivos de consumo masivo y el surgimiento de vulnerabilidades debido al uso de múltiples claves de acceso a diferentes sitios que requieren cierto nivel de seguridad como ser cuentas de correo, sitios de banca electrónica, sistemas corporativos, etc. De todos los rasgos utilizados en biometría, el i...

  6. Impacts of land-use and land-cover change on stream hydrochemistry in the Cerrado and Amazon biomes.

    Science.gov (United States)

    Nóbrega, Rodolfo L B; Guzha, Alphonce C; Lamparter, Gabriele; Amorim, Ricardo S S; Couto, Eduardo G; Hughes, Harold J; Jungkunst, Hermann F; Gerold, Gerhard

    2018-04-14

    Studies on the impacts of land-use and land-cover change on stream hydrochemistry in active deforestation zones of the Amazon agricultural frontier are limited and have often used low-temporal-resolution datasets. Moreover, these impacts are not concurrently assessed in well-established agricultural areas and new deforestations hotspots. We aimed to identify these impacts using an experimental setup to collect high-temporal-resolution hydrological and hydrochemical data in two pairs of low-order streams in catchments under contrasting land use and land cover (native vegetation vs. pasture) in the Amazon and Cerrado biomes. Our results indicate that the conversion of natural landscapes to pastures increases carbon and nutrient fluxes via streamflow in both biomes. These changes were the greatest in total inorganic carbon in the Amazon and in potassium in the Cerrado, representing a 5.0- and 5.5-fold increase in the fluxes of each biome, respectively. We found that stormflow, which is often neglected in studies on stream hydrochemistry in the tropics, plays a substantial role in the carbon and nutrient fluxes, especially in the Amazon biome, as its contributions to hydrochemical fluxes are mostly greater than the volumetric contribution to the total streamflow. These findings demonstrate that assessments of the impacts of deforestation in the Amazon and Cerrado biomes should also take into account rapid hydrological pathways; however, this can only be achieved through collection of high-temporal-resolution data. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Large-scale impact of climate change vs. land-use change on future biome shifts in Latin America.

    Science.gov (United States)

    Boit, Alice; Sakschewski, Boris; Boysen, Lena; Cano-Crespo, Ana; Clement, Jan; Garcia-Alaniz, Nashieli; Kok, Kasper; Kolb, Melanie; Langerwisch, Fanny; Rammig, Anja; Sachse, René; van Eupen, Michiel; von Bloh, Werner; Clara Zemp, Delphine; Thonicke, Kirsten

    2016-11-01

    Climate change and land-use change are two major drivers of biome shifts causing habitat and biodiversity loss. What is missing is a continental-scale future projection of the estimated relative impacts of both drivers on biome shifts over the course of this century. Here, we provide such a projection for the biodiverse region of Latin America under four socio-economic development scenarios. We find that across all scenarios 5-6% of the total area will undergo biome shifts that can be attributed to climate change until 2099. The relative impact of climate change on biome shifts may overtake land-use change even under an optimistic climate scenario, if land-use expansion is halted by the mid-century. We suggest that constraining land-use change and preserving the remaining natural vegetation early during this century creates opportunities to mitigate climate-change impacts during the second half of this century. Our results may guide the evaluation of socio-economic scenarios in terms of their potential for biome conservation under global change. © 2016 John Wiley & Sons Ltd.

  8. Biome depletion in conjunction with evolutionary mismatches could play a role in the etiology of neurofibromatosis 1.

    Science.gov (United States)

    Beales, Donna L

    2015-04-01

    Neurofibromatosis 1 (NF1) arises de novo in a striking 30-50% of cases, pointing toward an environmental etiology, though none has been clearly identified. The Biome Depletion Theory posits that the absence of mutualistic and commensal organisms within the human body coupled with modern lifestyle alterations may have profoundly deleterious effects, inclusive of immunologic derangement that is thought to result in allergy, atopy, and numerous autoimmune diseases. Biome depletion has been implicated as a factor in the etiology of both multiple sclerosis and autism spectrum disorders; biome reconstitution, i.e. replenishment of the biome with certain keynote species, is being used in the treatment of these and other autoimmune states. Neurofibromatosis 1 has been associated with allergy, various autoimmune states, multiple sclerosis, and autism. Recent research has posited that NF1, multiple sclerosis and autism may all arise from disturbances in the neural crest during gestation. This paper hypothesizes that there is indirect evidence that a highly inflammatory uterine state may precipitate epigenetic changes in vulnerable NF-related genes in the course of fetal development. The etiology of NF1 may lie in the absence of immunomodulation by commensal and mutualistic species once ubiquitously present in the environment, as well as through adoption of a modern lifestyle that contributes to chronic inflammation. Replenishment of helminths and other missing organisms to the human biome prior to conception as well as addressing nutritional status, psychological stress, and environmental exposures may prevent the development of NF1. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Terrestrial ecosystem process model Biome-BGCMuSo v4.0: summary of improvements and new modeling possibilities

    Science.gov (United States)

    Hidy, Dóra; Barcza, Zoltán; Marjanović, Hrvoje; Zorana Ostrogović Sever, Maša; Dobor, Laura; Gelybó, Györgyi; Fodor, Nándor; Pintér, Krisztina; Churkina, Galina; Running, Steven; Thornton, Peter; Bellocchi, Gianni; Haszpra, László; Horváth, Ferenc; Suyker, Andrew; Nagy, Zoltán

    2016-12-01

    The process-based biogeochemical model Biome-BGC was enhanced to improve its ability to simulate carbon, nitrogen, and water cycles of various terrestrial ecosystems under contrasting management activities. Biome-BGC version 4.1.1 was used as a base model. Improvements included addition of new modules such as the multilayer soil module, implementation of processes related to soil moisture and nitrogen balance, soil-moisture-related plant senescence, and phenological development. Vegetation management modules with annually varying options were also implemented to simulate management practices of grasslands (mowing, grazing), croplands (ploughing, fertilizer application, planting, harvesting), and forests (thinning). New carbon and nitrogen pools have been defined to simulate yield and soft stem development of herbaceous ecosystems. The model version containing all developments is referred to as Biome-BGCMuSo (Biome-BGC with multilayer soil module; in this paper, Biome-BGCMuSo v4.0 is documented). Case studies on a managed forest, cropland, and grassland are presented to demonstrate the effect of model developments on the simulation of plant growth as well as on carbon and water balance.

  10. Reproductive biology of Davilla kunthii A. St-Hil. (Dilleniaceae in Central Amazonia Biologia reprodutiva de Davilla kunthii A. St-Hil. (Dilleniaceae na Amazônia Central

    Directory of Open Access Journals (Sweden)

    André Rodrigo Rech

    2011-06-01

    Full Text Available This survey aimed at describing the interactions of floral visitors and Davilla kunthii A. St.-Hil. as well as characteristics of its reproductive biology in Itacoatiara, state of Amazonas, Brazil. Tests of the breeding system were performed. The guild of visitors was described according to richness, abundance, relative frequency and constancy. The breeding system tests indicated that D. kunthii is self-compatible. The pollination system was characterized as generalist, with 39 visitor species, from three different orders. Bees were the main group of pollinators, thus some behavioural aspects were described. Th e period of highest foraging activity was between 7 and 10 am. Some species presented agonistic and monopolistic behaviour. Given the behaviour and destructive potential, the Curculionidae seem to have a greater impact as seed predators than pollinators.Este trabalho descreve as relações entre visitantes florais e Davilla kunthii A. St.-Hil., bem como características de sua biologia reprodutiva em Itacoatiara (Amazonas. Foram realizados os testes referentes ao estudo do sistema reprodutivo. A guilda de visitantes foi caracterizada quanto à riqueza, abundância, frequência relativa e constância. Os testes para sistema reprodutivo indicaram que D. kunthii possui auto-compatibilidade. O mecanismo de polinização configurou-se como generalista com 39 espécies de visitantes florais, provenientes de três diferentes ordens. Abelhas corresponderam ao principal grupo de polinizadores, desta forma, alguns aspectos comportamentais foram descritos. O horário de maior forrageamento ocorreu entre 7 e 10 horas. Algumas espécies apresentaram interações agonísticas e comportamento monopolizador da fonte de alimento. Dado o comportamento e o potencial destrutivo, embora possa ocasionalmente atuar como polinizadores, Curculionidae parecem possuir maior impacto como predadores de sementes.

  11. Reproductive biology and diet of Mustelus punctulatus (Risso, 1826 (Chondrichthyes: Triakidae from the Gulf of Gabès, central Mediterranean Sea

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    Bechir Saïdi

    2009-06-01

    Full Text Available Specimens of Mustelus punctulatus were collected between January 2002 and December 2005 from commercial fisheries in the Gulf of Gabès (central Mediterranean Sea. Males and females reached a maximum total length (TL of 111 and 122 cm respectively. Males matured between 76 and 88.5 cm TL, with a size at maturity (TL50 of 81.4 cm TL. Females matured between 88 and 100 cm TL with a TL50 of 95.6 cm. Females had an annual reproductive cycle. Mating occurred through late-May and June. Ovulation occurred from early July to mid-August with parturition occurring from mid-May to early June, after a gestation period of 11 months. The size at birth was estimated to be 24.5 to 30.5 cm TL. Positive linear relationships were detected between the TL of mature females and ovarian and uterine fecundities. Mustelus punctulatus is an opportunistic predator that consumes a wide range of demersal and benthic prey items. It preys mainly on crustaceans, teleosts and molluscs. Polychaetes, sipunculids, echinoderms and tunicates are also consumed. The species change their main food item as they grow, from crustaceans to teleosts then to molluscs.

  12. The chemical and biological response of two remote mountain lakes in the Southern Central Alps (Italy to twenty years of changing physical and chemical climate

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    Andrea LAMI

    2004-02-01

    Full Text Available Two small high mountain lakes in the Alps were monitored in 1984-2003 to follow their response to changes in human impact, such as deposition of atmospheric pollutants, fish stocking and climate change. The results were compared to occasional samplings performed in the 1940s, and to the remains found in sediment cores. When monitoring started, the most acid-sensitive of them, Lake Paione Superiore, was acidified, with evident effects in its flora and fauna: benthic diatoms assemblage was shifted towards acidophilous species, and zooplankton lost the dominant species, Arctodiaptomus alpinus. Palaeolimnological studies outlined that lake acidification paralleled the increasing input of long-range transported industrial pollutants, traced by spherical carbonaceous particles. On the contrary, the biota of Lake Paione Inferiore appeared to be mainly affected by fish stocking. In the last twenty years, decrease in acid load from the atmosphere led to an improvement in lake water quality, with an increase in both pH and alkalinity. First signs of biological recovery were identified, such as change in diatom flora and appearance of sensitive species among benthic insects. However, climate change and episodic deposition of Saharan dust were important driving factors controlling lake water chemistry. Further monitoring to assess the effects of climate change and of the increasing load of nitrogen and other pollutants is recommended.

  13. Aspectos biométricos do desenvolvimento testicular e corporal em cutias (Dasyprocta aguti criadas em cativeiros

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    Antônio Chaves de Assis-Neto

    2003-01-01

    Full Text Available Analisou-se os dados biométricos do desenvolvimento testicular e peso corporal de 31 cutias (Dasyprocta aguti desde o nascimento até os 14 meses de idade. As correlações entre o peso corporal, idade e parâmetros testiculares apresentaram-se altamente significativas. O peso testicular, o volume testicular, assim como os demais parâmetros biométricos testiculares (comprimento, diâmetro e perímetro, evoluíram lenta e gradualmente até os 8 meses de idade. A partir dos 9 meses, o crescimento foi mais rápido. O desenvolvimento biométrico do testículo pode ser dividido em duas fases, de 0 - 8 meses e de 9 - 14 meses de idade, sendo 9 meses considerado ponto de corte em se tratando de desenvolvimento testicular de cutias criadas em cativeiro.

  14. The Use of Fire Radiative Power to Estimate the Biomass Consumption Coefficient for Temperate Grasslands in the Atlantic Forest Biome

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    Bibiana Salvador Cabral da Costa

    Full Text Available Abstract Every year, many active fire spots are identified in the satellite images of the southern Brazilian grasslands in the Atlantic Forest biome and Pampa biome. Fire Radiative Power (FRP is a technique that uses remotely sensed data to quantify burned biomass. FRP measures the radiant energy released per time unit by burning vegetation. This study aims to use satellite and field data to estimate the biomass consumption rate and the biomass consumption coefficient for the southern Brazilian grasslands. Three fire points were identified in satellite FRP products. These data were combined with field data, collected through literature review, to calculate the biomass consumption coefficient. The type of vegetation is an important variable in the estimation of the biomass consumption coefficient. The biomass consumption rate was estimated to be 2.237 kg s-1 for the southern Brazilian grasslands in Atlantic Forest biome, and the biomass consumption coefficient was estimated to be 0.242 kg MJ-1.

  15. Cross-biome metagenomic analyses of soil microbial communities and their functional attributes.

    Science.gov (United States)

    Fierer, Noah; Leff, Jonathan W; Adams, Byron J; Nielsen, Uffe N; Bates, Scott Thomas; Lauber, Christian L; Owens, Sarah; Gilbert, Jack A; Wall, Diana H; Caporaso, J Gregory

    2012-12-26

    For centuries ecologists have studied how the diversity and functional traits of plant and animal communities vary across biomes. In contrast, we have only just begun exploring similar questions for soil microbial communities despite soil microbes being the dominant engines of biogeochemical cycles and a major pool of living biomass in terrestrial ecosystems. We used metagenomic sequencing to compare the composition and functional attributes of 16 soil microbial communities collected from cold deserts, hot deserts, forests, grasslands, and tundra. Those communities found in plant-free cold desert soils typically had the lowest levels of functional diversity (diversity of protein-coding gene categories) and the lowest levels of phylogenetic and taxonomic diversity. Across all soils, functional beta diversity was strongly correlated with taxonomic and phylogenetic beta diversity; the desert microbial communities were clearly distinct from the nondesert communities regardless of the metric used. The desert communities had higher relative abundances of genes associated with osmoregulation and dormancy, but lower relative abundances of genes associated with nutrient cycling and the catabolism of plant-derived organic compounds. Antibiotic resistance genes were consistently threefold less abundant in the desert soils than in the nondesert soils, suggesting that abiotic conditions, not competitive interactions, are more important in shaping the desert microbial communities. As the most comprehensive survey of soil taxonomic, phylogenetic, and functional diversity to date, this study demonstrates that metagenomic approaches can be used to build a predictive understanding of how microbial diversity and function vary across terrestrial biomes.

  16. Detection of wild animals as carriers of Leptospira by PCR in the Pantanal biome, Brazil.

    Science.gov (United States)

    Vieira, Anahi S; Narduche, Lorena; Martins, Gabriel; Schabib Péres, Igor A H F; Zimmermann, Namor P; Juliano, Raquel S; Pellegrin, Aiesca O; Lilenbaum, Walter

    2016-11-01

    Leptospiral infection is widespread in wildlife. In this context, wild ecosystems in tropical countries hold a vast biodiversity, including several species that may act as potential reservoirs of leptospires. The Pantanal biome presents highly favorable environmental conditions for the occurrence of leptospirosis, such as high temperatures, constant flooding, and high biodiversity. The purpose of this study was to detect wild animals as carriers of Leptospira sp. using direct methods (PCR and culture) in the Pantanal biome, Brazil. A total of 35 animals were studied, namely Cerdocyon thous, Nasua nasua, Ozotoceros bezoarticus, and Sus scrofa species. Blood for serology (MAT) and urine for bacteriological culturing and PCR was sampled. The most prevalent serogroups were Javanica and Djasiman. Additionally, 40.6% of these animals presented PCR positive reactions. Seroreactivity associated with the high frequency of leptospiral carriers among the different studied species suggests a high level of exposure of the studied animals to pathogenic Leptospira strains. Our results are still limited and the actual role of the studied animals in the epidemiology of leptospirosis in the Pantanal region remains to be elucidated. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Temporal profiles of vegetation indices for characterizing grazing intensity on natural grasslands in Pampa biome

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    Amanda Heemann Junges

    2016-08-01

    Full Text Available ABSTRACT The Pampa biome is an important ecosystem in Brazil that is highly relevant to livestock production. The objective of this study was to analyze the potential use of vegetation indices to discriminate grazing intensities on natural grasslands in the Pampa biome. Moderate Resolution Imaging Spectroradiometer (MODIS Normalized Difference Vegetation Index (NDVI and Enhanced Vegetation Index (EVI images from Jan to Dec, 2000 to 2013 series, were analyzed for natural grassland experimental units managed under high (forage allowance of 5 ± 2 % live weight – LW, moderate (13 ± 5 % LW and low grazing intensity (19 ± 7 % LW. Regardless of intensity, the temporal profiles showed lower NDVI and EVI during winter, increased values in spring because of summer species regrowth, slightly decreased values in summer, especially in years when there is a water deficit, and increased values in the fall associated with the beginning of winter forage development. The average temporal profiles of moderate grazing intensity exhibited greater vegetation index values compared with low and high grazing intensities. The temporal profiles of less vegetation index were associated with lower green biomass accumulation caused by the negative impact of stocking rates on the leaf area index under high grazing intensity and a floristic composition with a predominance of tussocks under low grazing intensity. Vegetation indices can be used for distinguishing moderate grazing intensity from low and high intensities. The average EVI values can discriminate moderate grazing intensity during any season, and the NDVI values can discriminate moderate grazing intensity during spring and winter.

  18. Above- and Belowground Biomass Allocation in Shrub Biomes across the Northeast Tibetan Plateau

    Science.gov (United States)

    Yang, Yuanhe; Yang, Lucun; Zhou, Guoying

    2016-01-01

    Biomass partitioning has been explored across various biomes. However, the strategies of allocation in plants still remain contentious. This study investigated allocation patterns of above- and belowground biomass at the community level, using biomass survey from the Tibetan Plateau. We explored above- and belowground biomass by conducting three consecutive sampling campaigns across shrub biomes on the northeast Tibetan Plateau during 2011–2013. We then documented the above-ground biomass (AGB), below-ground biomass (BGB) and root: shoot ratio (R/S) and the relationships between R/S and environment factors using data from 201 plots surveyed from 67 sites. We further examined relationships between above-ground and below-ground biomass across various shrub types. Our results indicated that the median values of AGB, BGB, and R/S in Tibetan shrub were 1102.55, 874.91 g m-2, and 0.85, respectively. R/S showed significant trend with mean annual precipitation (MAP), while decreased with mean annual temperature (MAT). Reduced major axis analysis indicated that the slope of the log-log relationship between above- and belowground biomass revealed a significant difference from 1.0 over space, supporting the optimal hypothesis. Interestingly, the slopes of the allometric relationship between log AGB and log BGB differed significantly between alpine and desert shrub. Our findings supported the optimal theory of above- and belowground biomass partitioning in Tibetan shrub, while the isometric hypothesis for alpine shrub at the community level. PMID:27119379

  19. The deforestation story: testing for anthropogenic origins of Africa's flammable grassy biomes.

    Science.gov (United States)

    Bond, William; Zaloumis, Nicholas P

    2016-06-05

    Africa has the most extensive C4 grassy biomes of any continent. They are highly flammable accounting for greater than 70% of the world's burnt area. Much of Africa's savannas and grasslands occur in climates warm enough and wet enough to support closed forests. The combination of open grassy systems and the frequent fires they support have long been interpreted as anthropogenic artefacts caused by humans igniting frequent fires. True grasslands, it was believed, would be restricted to climates too dry or too cold to support closed woody vegetation. The idea that higher-rainfall savannas are anthropogenic and that fires are of human origin has led to initiatives to 'reforest' Africa's open grassy systems paid for by carbon credits under the assumption that the net effect of converting these system to forests would sequester carbon, reduce greenhouse gases and mitigate global warming. This paper reviews evidence for the antiquity of African grassy ecosystems and for the fires that they sustain. Africa's grassy biomes and the fires that maintain them are ancient and there is no support for the idea that humans caused large-scale deforestation. Indicators of old-growth grasslands are described. These can help distinguish secondary grasslands suitable for reforestation from ancient grasslands that should not be afforested.This article is part of the themed issue 'The interaction of fire and mankind'. © 2016 The Author(s).

  20. Contribution to the discussions on the origin of the cerrado biome: Brazilian savanna

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    MHO. Pinheiro

    Full Text Available Theories that attempt to explain the origin of the cerrado biome are mostly based on the isolated action of three major factors: climate, fire and soil. Another factor that has been mentioned is that of human interference. We hypothesise that the evolutionary origin of this biome resulted from the complex interaction of climate, fire and soil, with climate being the triggering agent of this assumed interaction. Fire, as well as acid and dystrophic soils, would be factors involved in the selection of savanna species throughout climatic events, during the Tertiary and the Quaternary, e.g. Pliocene and Pleistocene. The genesis of the physiognomies that would give rise to cerrado sensu lato, rather than forest formations, could have occurred due to the strong pressure exerted by the reduction in water availability, and the selection of the species adapted to the new conditions imposed by the environment. The characteristics of cerrado sensu lato soil, originated from edaphic impoverishment caused by lixiviation and successive past fires, would remain, even after hydric availability increased following the Pleistocene glaciations.

  1. NDVI and meteorological data as indicators of the Pampa biome natural grasslands growth

    Directory of Open Access Journals (Sweden)

    Denise Cybis Fontana

    2018-04-01

    Full Text Available ABSTRACT The present study aimed to characterize the dynamics of NDVI and meteorological conditions, relating both to the annual dynamics of biomass accumulation in natural pastures of the Pampa biome as a way of subsidizing growth modeling. Forage accumulation rate data from a long-term experiment, NDVI data from the MODIS images, and meteorological data measured at the surface were used. We verify that the agrometeorological element associated to the accumulation of forage in the natural grasslands is different according to the season, which is typical of the subtropical climate. Winter is the critical season for livestock production due to the lower forage accumulation rate and lower values of NDVI, conditioned by the decrease of solar radiation and air temperature. In the summer, the limiting factor to forage accumulation is the hydric condition. It was also verified that the variability in the growth of grasslands can be associated with the ENSO phenomenon, being the El Niño favorable and the La Niña unfavorable, especially in the spring-summer period. Considering the verified associations, spectral indices combined with agrometeorological elements are recommended to the adjustment of models of forage accumulation in the Pampa biome natural grasslands.

  2. Feedbacks between land cover and climate changes in the Brazilian Amazon and Cerrado biomes

    Science.gov (United States)

    Coe, M. T.; Silverio, D. V.; Bustamante, M.; Macedo, M.; Shimbo, J.; Brando, P. M.

    2016-12-01

    An estimated 20% of Amazon forests and 45% of Cerrado savannas have been cleared to make way for the expansion of croplands and pasturelands in Brazil. Although deforestation rates have decreased or remained steady over the last decade, the cumulative area deforested continues to grow in both biomes. These land-use transitions are expected to influence regional climate by reducing evapotranspiration (ET), increasing land surface temperatures (LST), and ultimately reducing regional precipitation. Here we present results from spatial analyses to quantify the impact of land-use transitions on the regional climate of the Amazon-Cerrado agricultural frontier. The analyses combine satellite observations and model outputs from the MODIS dataset. Results from the southeastern Amazon indicate that transitions from forest to pasture or cropland decreased mean annual ET (by 24% and 32%, respectively) and increased LST (by 4.2°C and 6.4°C). Preliminary results from the Cerrado indicate that transitions from woody savannas to pasture or cropland also result in substantial reductions in mean annual ET (23% and 20%, respectively) and increases in LST (by 1.6°C in both cases). These results reinforce the need to better understand how land-use change at regional scales may alter climate by changing ecosystem properties (beyond carbon stocks and fluxes). It is important to evaluate these responses across different biomes, particularly in tropical regions under increasing deforestation pressure.

  3. Cities as Novel Biomes;Recognizing Urban Ecosystem Services as Anthropogenic

    Directory of Open Access Journals (Sweden)

    Stephanie ePincetl

    2015-12-01

    Full Text Available Urban Ecosystem Science is now an established science, arising along side the historic shift of humans to becoming in majority urban dwellers. In this Perspective I suggest there is a need to develop a new framework for UES as embedded in distinct urban biomes that can be classified by city-type and typologized. UES are largely the artifact of human decision making from what to plant where, to determining the urban infrastructure type in which UES will be placed. Developing urban typologies by climate zone, level of development, size and history will better enable the understanding of UES. I attempt to show the rise of the importance of nature, and of urban nature following the development of industrial city, and the importance of human intent in creating these urban ecosystems over time. If humans choose to manage cities through increasing UES, this will require coupled shifts, the shift in rules and regulations, goals and processes and shifts in urban form, infrastructure and function – socio-technical-ecological changes – driven by human decision-making. Such efforts will vary widely by city -- by urban biome.

  4. Year-Long Monitoring of Physico-Chemical and Biological Variables Provide a Comparative Baseline of Coral Reef Functioning in the Central Red Sea

    KAUST Repository

    Roik, Anna Krystyna; Rö thig, Till; Roder, Cornelia; Ziegler, Maren; Kremb, Stephan Georg; Voolstra, Christian R.

    2016-01-01

    Coral reefs in the central Red Sea are sparsely studied and in situ data on physico-chemical and key biotic variables that provide an important comparative baseline are missing. To address this gap, we simultaneously monitored three reefs along a cross-shelf gradient for an entire year over four seasons, collecting data on currents, temperature, salinity, dissolved oxygen (DO), chlorophyll-a, turbidity, inorganic nutrients, sedimentation, bacterial communities of reef water, and bacterial and algal composition of epilithic biofilms. Summer temperature (29–33°C) and salinity (39 PSU) exceeded average global maxima for coral reefs, whereas DO concentration was low (2–4 mg L-1). While temperature and salinity differences were most pronounced between seasons, DO, chlorophyll-a, turbidity, and sedimentation varied most between reefs. Similarly, biotic communities were highly dynamic between reefs and seasons. Differences in bacterial biofilms were driven by four abundant families: Rhodobacteraceae, Flavobacteriaceae, Flammeovirgaceae, and Pseudanabaenaceae. In algal biofilms, green crusts, brown crusts, and crustose coralline algae were most abundant and accounted for most of the variability of the communities. Higher bacterial diversity of biofilms coincided with increased algal cover during spring and summer. By employing multivariate matching, we identified temperature, salinity, DO, and chlorophyll-a as the main contributing physico-chemical drivers of biotic community structures. These parameters are forecast to change most with the progression of ocean warming and increased nutrient input, which suggests an effect on the recruitment of Red Sea benthic communities as a result of climate change and anthropogenic influence. In conclusion, our study provides insight into coral reef functioning in the Red Sea and a comparative baseline to support coral reef studies in the region.

  5. Year-Long Monitoring of Physico-Chemical and Biological Variables Provide a Comparative Baseline of Coral Reef Functioning in the Central Red Sea.

    Science.gov (United States)

    Roik, Anna; Röthig, Till; Roder, Cornelia; Ziegler, Maren; Kremb, Stephan G; Voolstra, Christian R

    2016-01-01

    Coral reefs in the central Red Sea are sparsely studied and in situ data on physico-chemical and key biotic variables that provide an important comparative baseline are missing. To address this gap, we simultaneously monitored three reefs along a cross-shelf gradient for an entire year over four seasons, collecting data on currents, temperature, salinity, dissolved oxygen (DO), chlorophyll-a, turbidity, inorganic nutrients, sedimentation, bacterial communities of reef water, and bacterial and algal composition of epilithic biofilms. Summer temperature (29-33°C) and salinity (39 PSU) exceeded average global maxima for coral reefs, whereas DO concentration was low (2-4 mg L-1). While temperature and salinity differences were most pronounced between seasons, DO, chlorophyll-a, turbidity, and sedimentation varied most between reefs. Similarly, biotic communities were highly dynamic between reefs and seasons. Differences in bacterial biofilms were driven by four abundant families: Rhodobacteraceae, Flavobacteriaceae, Flammeovirgaceae, and Pseudanabaenaceae. In algal biofilms, green crusts, brown crusts, and crustose coralline algae were most abundant and accounted for most of the variability of the communities. Higher bacterial diversity of biofilms coincided with increased algal cover during spring and summer. By employing multivariate matching, we identified temperature, salinity, DO, and chlorophyll-a as the main contributing physico-chemical drivers of biotic community structures. These parameters are forecast to change most with the progression of ocean warming and increased nutrient input, which suggests an effect on the recruitment of Red Sea benthic communities as a result of climate change and anthropogenic influence. In conclusion, our study provides insight into coral reef functioning in the Red Sea and a comparative baseline to support coral reef studies in the region.

  6. Year-Long Monitoring of Physico-Chemical and Biological Variables Provide a Comparative Baseline of Coral Reef Functioning in the Central Red Sea

    KAUST Repository

    Roik, Anna Krystyna

    2016-11-09

    Coral reefs in the central Red Sea are sparsely studied and in situ data on physico-chemical and key biotic variables that provide an important comparative baseline are missing. To address this gap, we simultaneously monitored three reefs along a cross-shelf gradient for an entire year over four seasons, collecting data on currents, temperature, salinity, dissolved oxygen (DO), chlorophyll-a, turbidity, inorganic nutrients, sedimentation, bacterial communities of reef water, and bacterial and algal composition of epilithic biofilms. Summer temperature (29–33°C) and salinity (39 PSU) exceeded average global maxima for coral reefs, whereas DO concentration was low (2–4 mg L-1). While temperature and salinity differences were most pronounced between seasons, DO, chlorophyll-a, turbidity, and sedimentation varied most between reefs. Similarly, biotic communities were highly dynamic between reefs and seasons. Differences in bacterial biofilms were driven by four abundant families: Rhodobacteraceae, Flavobacteriaceae, Flammeovirgaceae, and Pseudanabaenaceae. In algal biofilms, green crusts, brown crusts, and crustose coralline algae were most abundant and accounted for most of the variability of the communities. Higher bacterial diversity of biofilms coincided with increased algal cover during spring and summer. By employing multivariate matching, we identified temperature, salinity, DO, and chlorophyll-a as the main contributing physico-chemical drivers of biotic community structures. These parameters are forecast to change most with the progression of ocean warming and increased nutrient input, which suggests an effect on the recruitment of Red Sea benthic communities as a result of climate change and anthropogenic influence. In conclusion, our study provides insight into coral reef functioning in the Red Sea and a comparative baseline to support coral reef studies in the region.

  7. Year-Long Monitoring of Physico-Chemical and Biological Variables Provide a Comparative Baseline of Coral Reef Functioning in the Central Red Sea.

    Directory of Open Access Journals (Sweden)

    Anna Roik

    Full Text Available Coral reefs in the central Red Sea are sparsely studied and in situ data on physico-chemical and key biotic variables that provide an important comparative baseline are missing. To address this gap, we simultaneously monitored three reefs along a cross-shelf gradient for an entire year over four seasons, collecting data on currents, temperature, salinity, dissolved oxygen (DO, chlorophyll-a, turbidity, inorganic nutrients, sedimentation, bacterial communities of reef water, and bacterial and algal composition of epilithic biofilms. Summer temperature (29-33°C and salinity (39 PSU exceeded average global maxima for coral reefs, whereas DO concentration was low (2-4 mg L-1. While temperature and salinity differences were most pronounced between seasons, DO, chlorophyll-a, turbidity, and sedimentation varied most between reefs. Similarly, biotic communities were highly dynamic between reefs and seasons. Differences in bacterial biofilms were driven by four abundant families: Rhodobacteraceae, Flavobacteriaceae, Flammeovirgaceae, and Pseudanabaenaceae. In algal biofilms, green crusts, brown crusts, and crustose coralline algae were most abundant and accounted for most of the variability of the communities. Higher bacterial diversity of biofilms coincided with increased algal cover during spring and summer. By employing multivariate matching, we identified temperature, salinity, DO, and chlorophyll-a as the main contributing physico-chemical drivers of biotic community structures. These parameters are forecast to change most with the progression of ocean warming and increased nutrient input, which suggests an effect on the recruitment of Red Sea benthic communities as a result of climate change and anthropogenic influence. In conclusion, our study provides insight into coral reef functioning in the Red Sea and a comparative baseline to support coral reef studies in the region.

  8. Temporal and spatial variability of biological nitrogen fixation off the upwelling system of central Chile (35-38.5°S)

    Science.gov (United States)

    Fernandez, Camila; González, Maria Lorena; Muñoz, Claudia; Molina, Veronica; Farias, Laura

    2015-05-01

    Although N2 fixation could represent a supplementary source of bioavailable nitrogen in coastal upwelling areas and underlying oxygen minimum zones (OMZs), the limited data available prevent assessing its variability and biogeochemical significance. Here we report the most extensive N2 fixation data set gathered to date in the upwelling area off central Chile (36°S). It covers interannual to high frequency time scales in an area of about 82,500 km2 in the eastern South Pacific (ESP). Because heterotrophic N2 fixation may be regulated by DOM availability in the ESP, we conducted experiments at different oxygen conditions and included DOM amendments in order to test diazotrophic activity. Rates in the euphotic zone showed strong temporal variability which resulted in values reaching 0.5 nmol L-1 d-1 in 2006 (average 0.32 ± 0.17 nmol L-1 d-1) and up to 126.8 nmol L-1 d-1 (average 24.75 ± 37.9 nmol L-1 d-1) in 2011. N2 fixation in subsurface suboxic conditions (1.5 ± 1.16 nmol L-1 d-1) also occurred mainly during late summer and autumn while virtually absent in winter. The diversity of diazotrophs was dominated by heterotrophs, with higher richness in surface compared to OMZ waters. Rates in oxygen depleted conditions could exceed values obtained in the euphotic layer, but rates were not dependent on the availability of dissolved organic matter. N2 fixation also showed a positive correlation with total chlorophyll and the C:N ratio of phytoplankton, but not to the P excess compared to N. We conclude that the diazotrophic community responds to the composition of phytoplankton rather than the extent of N deficiency and the availability of bulk DOM in this system.

  9. A biome-scale assessment of the impact of invasive alien plants on ecosystem services in South Africa.

    Science.gov (United States)

    van Wilgen, B W; Reyers, B; Le Maitre, D C; Richardson, D M; Schonegevel, L

    2008-12-01

    This paper reports an assessment of the current and potential impacts of invasive alien plants on selected ecosystem services in South Africa. We used data on the current and potential future distribution of 56 invasive alien plant species to estimate their impact on four services (surface water runoff, groundwater recharge, livestock production and biodiversity) in five terrestrial biomes. The estimated reductions in surface water runoff as a result of current invasions were >3000 million m(3) (about 7% of the national total), most of which is from the fynbos (shrubland) and grassland biomes; the potential reductions would be more than eight times greater if invasive alien plants were to occupy the full extent of their potential range. Impacts on groundwater recharge would be less severe, potentially amounting to approximately 1.5% of the estimated maximum reductions in surface water runoff. Reductions in grazing capacity as a result of current levels of invasion amounted to just over 1% of the potential number of livestock that could be supported. However, future impacts could increase to 71%. A 'biodiversity intactness index' (the remaining proportion of pre-modern populations) ranged from 89% to 71% for the five biomes. With the exception of the fynbos biome, current invasions have almost no impact on biodiversity intactness. Under future levels of invasion, however, these intactness values decrease to around 30% for the savanna, fynbos and grassland biomes, but to even lower values (13% and 4%) for the two karoo biomes. Thus, while the current impacts of invasive alien plants are relatively low (with the exception of those on surface water runoff), the future impacts could be very high. While the errors in these estimates are likely to be substantial, the predicted impacts are sufficiently large to suggest that there is serious cause for concern.

  10. Breeding biology and distyly in Palicourea rigida H. B. & K. (Rubiaceae in the Cerrados of Central Brazil Biologia reprodutiva e distilia em Palicourea rigida H. B. & K. (Rubiaceae em Cerrados do Brasil Central

    Directory of Open Access Journals (Sweden)

    Adriana de Oliveira Machado

    2010-09-01

    Full Text Available Distyly is a floral polymorphism more common among the Rubiaceae than in any other angiosperm group. Palicourea rigida is a typically distylous species of the Rubiaceae widely distributed in the Brazilian Cerrados. This work aimed to study the floral biology and breeding system of P. rigida in order to verify if there wasasymmetry between floral morphs. The work was carried out at Fazenda Água Limpa, Brasília-DF, from 1993 to 1995; and at Serra Caldas Novas State Park-Goias and in Clube Caça e Pesca Itororó de Uberlândia-Minas Gerais in 2005 and 2006. Density, height and pin/thrum ratio were assessed for flowering individuals in all areas. Plants were investigated for differences in floral morphology, nectar production, reproductive success and site of self incompatibility reactions. Blooming period was long and concentrated during the rains. Flowers were clearly distylous and with reciprocal herkogamy. They produced nectar and lasted for a single day. In spite of differences in density and height, populations were mostly isoplethic. Nectar production varied in volume and concentration but the differences could not be associated with floral morphs. The species is self-incompatible but reproductive success was always high and independent of floral morphs. There were differences in the site of incompatibility barriers between floral morphs, which were similar to those observed for other Rubiaceae. The main floral visitors and pollinators were the hummingbirds Colibri serrirostris and Eupetomena macroura. High fruit-set indicates that the pollinators transported enough compatible pollen grains between floral morphs, despite their territorial behavior.A distilia é um polimorfismo floral mais freqüente entre as espécies de Rubiaceae do que em qualquer outro grupo das Angiospermas. Palicourea rigida é uma espécie de Rubiaceae, amplamente distribuída nos cerrados brasileiros e em outras áreas de savanas neotropicais. O presente trabalho

  11. Structural development and web service based sensitivity analysis of the Biome-BGC MuSo model

    Science.gov (United States)

    Hidy, Dóra; Balogh, János; Churkina, Galina; Haszpra, László; Horváth, Ferenc; Ittzés, Péter; Ittzés, Dóra; Ma, Shaoxiu; Nagy, Zoltán; Pintér, Krisztina; Barcza, Zoltán

    2014-05-01

    Studying the greenhouse gas exchange, mainly the carbon dioxide sink and source character of ecosystems is still a highly relevant research topic in biogeochemistry. During the past few years research focused on managed ecosystems, because human intervention has an important role in the formation of the land surface through agricultural management, land use change, and other practices. In spite of considerable developments current biogeochemical models still have uncertainties to adequately quantify greenhouse gas exchange processes of managed ecosystem. Therefore, it is an important task to develop and test process-based biogeochemical models. Biome-BGC is a widely used, popular biogeochemical model that simulates the storage and flux of water, carbon, and nitrogen between the ecosystem and the atmosphere, and within the components of the terrestrial ecosystems. Biome-BGC was originally developed by the Numerical Terradynamic Simulation Group (NTSG) of University of Montana (http://www.ntsg.umt.edu/project/biome-bgc), and several other researchers used and modified it in the past. Our research group developed Biome-BGC version 4.1.1 to improve essentially the ability of the model to simulate carbon and water cycle in real managed ecosystems. The modifications included structural improvements of the model (e.g., implementation of multilayer soil module and drought related plant senescence; improved model phenology). Beside these improvements management modules and annually varying options were introduced and implemented (simulate mowing, grazing, planting, harvest, ploughing, application of fertilizers, forest thinning). Dynamic (annually varying) whole plant mortality was also enabled in the model to support more realistic simulation of forest stand development and natural disturbances. In the most recent model version separate pools have been defined for fruit. The model version which contains every former and new development is referred as Biome-BGC MuSo (Biome

  12. Análisis comparativo de distintas toolkits para el reconocimiento biométrico de personas mediante voz

    OpenAIRE

    Ruíz, Silvia; Miranda, Ernesto; Herlein, Mauro; Etchart, Graciela; Alvez, Carlos E.

    2017-01-01

    El objetivo de este trabajo es realizar un análisis comparativo de distintas toolkits para el reconocimiento biométrico de personas mediante voz. Hoy en día los sistemas de identificación de personas se han convertido en una necesidad para la sociedad. A medida que avanza la tecnología y la aplicación de la misma en entornos tanto de ocio como de seguridad, la evolución en desarrollo biométrico es muy grande. Los sistemas de identificación o verificación tradicionales (tarjetas o claves) se h...

  13. Improved clonality detection in B-cell lymphoma using a semi-nested modification of the BIOMED-2 PCR assay for IGH rearrangement: A paraffin-embedded tissue study.

    Science.gov (United States)

    Sakamoto, Yuma; Masaki, Ayako; Aoyama, Satsuki; Han, Shusen; Saida, Kosuke; Fujii, Kana; Takino, Hisashi; Murase, Takayuki; Iida, Shinsuke; Inagaki, Hiroshi

    2017-09-01

    The BIOMED-2 PCR protocol for targeting the IGH gene is widely employed for detecting clonality in B-cell malignancies. Unfortunately, the detection of clonality with this method is not very sensitive when paraffin sections are used as a DNA source. To increase the sensitivity, we devised a semi-nested modification of a JH consensus primer. The clonality detection rates of three assays were compared: the standard BIOMED-2, BIOMED-2 assay followed by BIOMED-2 re-amplification, and BIOMED-2 assay followed by semi-nested BIOMED-2. We tested more than 100 cases using paraffin-embedded tissues of various B-cell lymphomas, and found that the clonality detection rates with the above three assays were 63.9%, 79.6%, and 88.0%, respectively. While BIOMED-2 re-amplification was significantly more sensitive than the standard BIOMED-2, the semi-nested BIOMED-2 was significantly more sensitive than both the standard BIOMED-2 and BIOMED-2 re-amplification. An increase in sensitivity was observed in all lymphoma subtypes examined. In conclusion, tumor clonality may be detected in nearly 90% of B-cell lymphoma cases with semi-nested BIOMED-2. This ancillary assay may be useful when the standard BIOMED-2 fails to detect clonality in histopathologically suspected B-cell lymphomas. © 2017 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

  14. Central Dogma Goes Digital.

    Science.gov (United States)

    Lin, Yihan; Elowitz, Michael B

    2016-03-17

    In this issue of Molecular Cell, Tay and colleagues (Albayrak et al., 2016) describe a new technique to digitally quantify the numbers of protein and mRNA in the same mammalian cell, providing a new way to look at the central dogma of molecular biology. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Plant litter dynamics in the forest-stream interface: precipitation is a major control across tropical biomes.

    Science.gov (United States)

    Tonin, Alan M; Gonçalves, José F; Bambi, Paulino; Couceiro, Sheyla R M; Feitoza, Lorrane A M; Fontana, Lucas E; Hamada, Neusa; Hepp, Luiz U; Lezan-Kowalczuk, Vânia G; Leite, Gustavo F M; Lemes-Silva, Aurea L; Lisboa, Leonardo K; Loureiro, Rafael C; Martins, Renato T; Medeiros, Adriana O; Morais, Paula B; Moretto, Yara; Oliveria, Patrícia C A; Pereira, Evelyn B; Ferreira, Lidiane P; Pérez, Javier; Petrucio, Mauricio M; Reis, Deusiano F; S Rezende, Renan; Roque, Nadia; Santos, Luiz E P; Siegloch, Ana E; Tonello, Gabriela; Boyero, Luz

    2017-09-07

    Riparian plant litter is a major energy source for forested streams across the world and its decomposition has repercussions on nutrient cycling, food webs and ecosystem functioning. However, we know little about plant litter dynamics in tropical streams, even though the tropics occupy 40% of the Earth's land surface. Here we investigated spatial and temporal (along a year cycle) patterns of litter inputs and storage in multiple streams of three tropical biomes in Brazil (Atlantic forest, Amazon forest and Cerrado savanna), predicting major differences among biomes in relation to temperature and precipitation regimes. Precipitation explained most of litter inputs and storage, which were generally higher in more humid biomes (litterfall: 384, 422 and 308 g m -2 y -1 , storage: 55, 113 and 38 g m -2 , on average in Atlantic forest, Amazon and Cerrado, respectively). Temporal dynamics varied across biomes in relation to precipitation and temperature, with uniform litter inputs but seasonal storage in Atlantic forest streams, seasonal inputs in Amazon and Cerrado streams, and aseasonal storage in Amazon streams. Our findings suggest that litter dynamics vary greatly within the tropics, but point to the major role of precipitation, which contrasts with the main influence of temperature in temperate areas.

  16. Tropical rainforest biome of Biosphere 2. Structure, composition and results of the first 2 years of operation

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, Linda S. [Systems Ecology and Energy Analysis Program, Department of Environmental Engineering Sciences, University of Florida, Gainesville, FL (United States); Burgess, Tony; Marino, Bruno D.V.; Wei, Yong Dan [Biosphere 2 Center, Inc. P.O. Box 689, Oracle, AZ (United States)

    1999-06-01

    The tropical rainforest biome in the Biosphere 2 mesocosm was managed with rainfall and temperature conditions to simulate a natural rainforest typical of the new world tropics. The establishment of the biome was based on the introduction of excessive numbers of species allowing self-organization of an ecologically unique rainforest. Over 282 species of plants from rainforest areas were planted within the topographically diverse rainforest biome (area of 1900 m{sup 2}, volume of 35,000 m{sup 3}), just before the Biosphere 2 closure in 1991. Approximately 61% of these species survived when counted in 1993, representing a plant species richness reduction to 172 species in 0.19 hectare. Rank order graphs show that a high diversity community resulted not unlike insular rainforests. The plants of the rainforest mesocosm, however, grew under anomalous conditions of soil (amended desert grassland soil), atmospheric composition (CO{sub 2} up to 4500 ppm by volume (ppmv)) and rainwater composition (high salinity and nutrients). Stem growth rates of a dominant canopy tree, Cecropia, were up to four times higher but had reduced diameter at breast height compared to natural counterparts. Human intervention in plant succession was also an important factor in shaping the ecology of the rainforest biome of Biosphere 2

  17. Adapting the Biome-BGC Model to New Zealand Pastoral Agriculture: Climate Change and Land-Use Change

    Science.gov (United States)

    Keller, E. D.; Baisden, W. T.; Timar, L.

    2011-12-01

    We have adapted the Biome-BGC model to make climate change and land-use scenario estimates of New Zealand's pasture production in 2020 and 2050, with comparison to a 2005 baseline. We take an integrated modelling approach with the aim of enabling the model's use for policy assessments across broadly related issues such as climate change mitigation and adaptation, land-use change, and greenhouse gas projections. The Biome-BGC model is a biogeochemical model that simulates carbon, water, and nitrogen cycles in terrestrial ecosystems. We introduce two new 'ecosystems', sheep/beef and dairy pasture, within the existing structure of the Biome-BGC model and calibrate its ecophysiological parameters against pasture clipping data from diverse sites around New Zealand to form a baseline estimate of total New Zealand pasture production. Using downscaled AR4 climate projections, we construct mid- and upper-range climate change scenarios in 2020 and 2050. We produce land-use change scenarios in the same years by combining the Biome-BGC model with the Land Use in Rural New Zealand (LURNZ) model. The LURNZ model uses econometric approaches to predict future land-use change driven by changes in net profits driven by expected pricing, including the introduction of an emission trading system. We estimate the relative change in national pasture production from our 2005 baseline levels for both sheep/beef and dairy systems under each scenario.

  18. Scaling net ecosystem production and net biome production over a heterogeneous region in the Western United States

    Science.gov (United States)

    D.P. Turner; W.D. Ritts; B.E. Law; W.B. Cohen; Z. Yan; T. Hudiburg; J.L. Campbell; M. Duane

    2007-01-01

    Bottom-up scaling of net ecosystem production (NEP) and net biome production (NBP) was used to generate a carbon budget for a large heterogeneous region (the state of Oregon, 2.5x105 km2 ) in the Western United States. Landsat resolution (30 m) remote sensing provided the basis for mapping land cover and disturbance history...

  19. Physiology of Saccharomyces cerevisiae strains isolated from Brazilian biomes: new insights into biodiversity and industrial applications

    DEFF Research Database (Denmark)

    Beato, Felipe B.; Bergdahl, Basti; Rosa, Carlos A.

    2016-01-01

    Fourteen indigenous Saccharomyces cerevisiae strains isolated from the barks of three tree species located in the Atlantic Rain Forest and Cerrado biomes in Brazil were genetically and physiologically compared to laboratory strains and to strains from the Brazilian fuel ethanol industry. Although...

  20. Modeling impacts of human footprint and soil variability on the potential distribution of invasive plant species in different biomes

    Science.gov (United States)

    Wan, Ji-Zhong; Wang, Chun-Jing; Yu, Fei-Hai

    2017-11-01

    Human footprint and soil variability may be important in shaping the spread of invasive plant species (IPS). However, until now, there is little knowledge on how human footprint and soil variability affect the potential distribution of IPS in different biomes. We used Maxent modeling to project the potential distribution of 29 IPS with wide distributions and long introduction histories in China based on various combinations of climatic correlates, soil characteristics and human footprint. Then, we evaluated the relative importance of each type of environmental variables (climate, soil and human footprint) as well as the difference in range and similarity of the potential distribution of IPS between different biomes. Human footprint and soil variables contributed to the prediction of the potential distribution of IPS, and different types of biomes had varying responses and degrees of impacts from the tested variables. Human footprint and soil variability had the highest tendency to increase the potential distribution of IPS in Montane Grasslands and Shrublands. We propose to integrate the assessment in impacts of human footprint and soil variability on the potential distribution of IPS in different biomes into the prevention and control of plant invasion.

  1. A method to determine warm and cool steppe biomes from pollen data; application to the Mediterranean and Kazakhstan regions

    NARCIS (Netherlands)

    Tarasov, PE; Cheddadi, R; Guiot, J; Bottema, S; Peyron, O; Belmonte, J; Ruiz-Sanchez, [No Value; Saadi, F; Brewer, S

    1998-01-01

    An objective method for the assignment of pollen spectra to appropriate biomes has been published recently. The aim of this paper is to improve the distinction between warm and cool steppes, thus refining vegetation and climate reconstruction, particularly during the Last Glacial Maximum. A set of

  2. The global extent and determinants of savanna and forest as alternative biome states.

    Science.gov (United States)

    Staver, A Carla; Archibald, Sally; Levin, Simon A

    2011-10-14

    Theoretically, fire-tree cover feedbacks can maintain savanna and forest as alternative stable states. However, the global extent of fire-driven discontinuities in tree cover is unknown, especially accounting for seasonality and soils. We use tree cover, climate, fire, and soils data sets to show that tree cover is globally discontinuous. Climate influences tree cover globally but, at intermediate rainfall (1000 to 2500 millimeters) with mild seasonality (less than 7 months), tree cover is bimodal, and only fire differentiates between savanna and forest. These may be alternative states over large areas, including parts of Amazonia and the Congo. Changes in biome distributions, whether at the cost of savanna (due to fragmentation) or forest (due to climate), will be neither smooth nor easily reversible.

  3. BOREAS RSS-8 BIOME-BGC SSA Simulation of Annual Water and Carbon Fluxes

    Science.gov (United States)

    Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Kimball, John

    2000-01-01

    The BOREAS RSS-8 team performed research to evaluate the effect of seasonal weather and landcover heterogeneity on boreal forest regional water and carbon fluxes using a process-level ecosystem model, BIOME-BGC, coupled with remote sensing-derived parameter maps of key state variables. This data set contains derived maps of landcover type and crown and stem biomass as model inputs to determine annual evapotranspiration, gross primary production, autotrophic respiration, and net primary productivity within the BOREAS SSA-MSA, at a 30-m spatial resolution. Model runs were conducted over a 3-year period from 1994-1996; images are provided for each of those years. The data are stored in binary image format. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  4. Overview on Environmental Comprehensive Management System Established in Imitation of Biome

    Institute of Scientific and Technical Information of China (English)

    李如燕; 孙可伟

    2004-01-01

    Environmental comprehensive management system, called "the bionic community", can be established in imitation of biome, which can transform the wastes generated in a certain field into the raw materials of other field. The establishment of the bionic community includes two aspects, i.e. , the matching technique and the management system. The main matching technique is the preparation of composite materials made of various wastes.This new kind of material can be divided into four types: polymer matrix, silicate matrix, metal matrix and carbon matrix (or ceramic matrix). The environmental comprehensive management system is formed by organizing a transtrades joint-management business entity with the products of composite material made of wastes at the core.

  5. Biométria de frutos e sementes de Luetzelburgia auriculata (Allemão Ducke

    Directory of Open Access Journals (Sweden)

    Roberto Ferreira Barroso

    2016-12-01

    Full Text Available A Caatinga apresenta uma grande diversidade de espécies vegetais, dentre elas Luetzelburgia auriculata é uma das espécies predominantes no bioma, desempenhando papel fundamental para o ecossistema local. Este trabalho objetivou descrever as características biométricas de frutos e sementes de Luetzelburgia auriculata.  Para a descrição das características da semente foram coletados 200 frutos e 200 sementes de plantas nativas do município de Santa Helena, Paraíba. As amostras foram encaminhadas ao Laboratório de Nutrição Mineral de Plantas do Centro de Saúde e Tecnologia Rural de Universidade Federal de Campina Grande para a realização das devidas aferições biométricas. Os frutos foram analisado pelo comprimento, espessura superior, mediana e inferior; largura superior, mediana e inferior. Para as sementes, foram analisados comprimento, espessura e a largura. Verificou-se que o comprimento dos frutos variou de 50,7 a 98,2 cm, a espessura de 6,00 a 17 mm e largura variando de 12,4 a 21,8 mm. Em relação às sementes, 46% se enquadraram na classe de comprimento com intervalo de 19,9 a 20,8 mm. A espécie Luetzelburgia auriculata apresentam variabilidade nas características biométricas de frutos e sementesBiometrics of fruit and seeds of Luetzelburgia auriculata (Allemão DuckeAbstract: The Caatinga presents a great diversity of plant species, among them the woodpecker (Luetzelburgia auriculata (Allemao Ducke. is one of the predominant species in the biome, playing a fundament al role for the local ecosystem. This work aimed to describe the biometric characteristics of fruits and seeds of Pau de Pedra. For the description of the characteristics of the Luetzelburgia auriculata (Allemão Ducke seed, 200 fruits and 200 seeds of native plants of the municipality of Santa Helena, Paraíba state were collected for biometry and seed mass. Afterwards they were packed in plastic bags and properly identified and taken to Laboratório de

  6. Autenticación mediante parámetros biométricos

    OpenAIRE

    Pastor Navarro, Ricard

    2017-01-01

    En les pàgines següents s’explicarà el procés seguit per la realització d’aquest treball de final de grau, en el que es pretén substituir, en un programa de gestió de contrasenyes, la contrasenya mestre per paràmetres biomètrics, concretament el reconeixement facial. Per a complir amb aquest objectiu s’utilitzaran alguns algoritmes de visió per computador extrets de les llibreries de OpenCV. El sistema final agafarà imatges de l’usuari i fent la comprovació del usuari decidint si ha de donar ...

  7. Genetic Divergence in Eucalyptus camaldulensis Progenies in the Savanna Biome in Mato Grosso, Brazil.

    Directory of Open Access Journals (Sweden)

    Reginaldo Brito da Costa

    Full Text Available Assessing the parental genetic differences and their subsequent prediction of progeny performance is an important first step to assure the efficiency of any breeding program. In this study, we estimate the genetic divergence in Eucalyptus camaldulensis based on the morphological traits of 132 progenies grown in a savanna biome. Thus, a field experiment was performed using a randomized block design and five replications to compare divergences in total height, commercial height, diameter at breast height, stem form and survival rate at 48 months. Tocher's clustering method was performed using the Mahalanobis and Euclidian distances. The Mahalanobis distance seemed more reliable for the assessed parameters and clustered all of the progenies into fourteen major groups. The most similar progenies (86 accessions were clustered into Group I, while the most dissimilar (1 progeny represented Group XIV. The divergence analysis indicated that promising crosses could be made between progenies allocated in different groups for high genetic divergence and for favorable morphological traits.

  8. Tundra biome research in Alaska: the structure and function of cold-dominated ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, J.; West, G.C.

    1970-11-01

    The objective of the Tundra Biome Program is to acquire a basic understanding of tundra, both alpine and arctic, and taiga. Collectively these are referred to as the cold-dominated ecosystems. The program's broad objectives are threefold: To develop a predictive understanding of how the wet arctic tundra ecosystem operates, particularly as exemplified in the Barrow, Alaska, area; to obtain the necessary data base from the variety of cold-dominated ecosystem types represented in the United States, so that their behavior can be modeled and simulated, and the results compared with similar studies underway in other circumpolar countries; to bring basic environmental knowledge to bear on problems of degradation, maintenance, and restoration of the temperature-sensitive and cold-dominated tundra/taiga ecosystems. (GRA)

  9. The rise and fall of central dogmas.

    Science.gov (United States)

    Klein, George; Klein, Eva

    2016-01-01

    Stimulated by Francis Cricks "central dogma of molecular biology" open to criticism and rebuttal, five statements are formulated on current notions of tumor biology, inviting the criticism of the reader.

  10. Microbial Community Profile and Water Quality in a Protected Area of the Caatinga Biome.

    Science.gov (United States)

    Lopes, Fabyano Alvares Cardoso; Catão, Elisa Caldeira Pires; Santana, Renata Henrique; Cabral, Anderson de Souza; Paranhos, Rodolfo; Rangel, Thiago Pessanha; de Rezende, Carlos Eduardo; Edwards, Robert A; Thompson, Cristiane C; Thompson, Fabiano L; Kruger, Ricardo Henrique

    2016-01-01

    The Caatinga is a semi-arid biome in northeast Brazil. The Paraguaçú River is located in the Caatinga biome, and part of its course is protected by the National Park of Chapada Diamantina (PNCD). In this study we evaluated the effect of PNCD protection on the water quality and microbial community diversity of this river by analyzing water samples obtained from points located inside and outside the PNCD in both wet and dry seasons. Results of water quality analysis showed higher levels of silicate, ammonia, particulate organic carbon, and nitrite in samples from the unprotected area compared with those from protected areas. Pyrosequencing of the 16S rRNA genes revealed that Burkholderiales was abundant in samples from all three sites during both seasons and was represented primarily by the genus Polynucleobacter and members of the Comamonadaceae family (e.g., genus Limnohabitans). During the dry season, the unprotected area showed a higher abundance of Flavobacterium sp. and Arthrobacter sp., which are frequently associated with the presence and/or degradation of arsenic and pesticide compounds. In addition, genes that appear to be related to agricultural impacts on the environment, as well as those involved in arsenic and cadmium resistance, copper homeostasis, and propanediol utilization, were detected in the unprotected areas by metagenomic sequencing. Although PNCD protection improves water quality, agricultural activities around the park may affect water quality within the park and may account for the presence of bacteria capable of pesticide degradation and assimilation, evidencing possible anthropogenic impacts on the Caatinga.

  11. Trans-biome diversity in Australian grass-specialist lizards (Diplodactylidae: Strophurus).

    Science.gov (United States)

    Laver, Rebecca J; Nielsen, Stuart V; Rosauer, Dan F; Oliver, Paul M

    2017-10-01

    Comparisons of biodiversity patterns within lineages that occur across major climate gradients and biomes, can provide insights into the relative roles that lineage history, landscape and climatic variation, and environmental change have played in shaping regional biotas. In Australia, while there has been extensive research into the origins and patterns of diversity in the Australian Arid Zone (AAZ), how diversity is distributed across this biome and the Australian Monsoonal Tropics (AMT) to the north, has been less studied. We compared the timing and patterns of diversification across this broad aridity gradient in a clade of lizards (Strophurus: phasmid geckos) that only occur in association with a unique Australian radiation of sclerophyllous grasses (Triodia: spinifex). Our results indicate that overall genetic diversity is much higher, older and more finely geographically structured within the AMT, including distantly related clades endemic to the sandstone escarpments of the Kimberley and Arnhem Plateau. Niche modelling analyses also suggest that the distribution of taxa in the AMT is more strongly correlated with variation in topographic relief than in the AAZ. The two broad patterns that we recovered - (i) lineage endemism increases as latitude decreases, and (ii) endemism is tightly correlated to rocky regions - parallel and corroborate other recent studies of habitat generalists and specialised saxicoline lineages occurring across these same regions. Early Miocene diversification estimates also suggest that, soon after Triodia grasses colonised Australia and began to diversify in the Miocene, phasmid geckos with Gondwanan ancestry shifted into these grasses, and have subsequently remained closely associated with this unique vegetation type. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Biome-scale nitrogen fixation strategies selected by climatic constraints on nitrogen cycle.

    Science.gov (United States)

    Sheffer, Efrat; Batterman, Sarah A; Levin, Simon A; Hedin, Lars O

    2015-11-23

    Dinitrogen fixation by plants (in symbiosis with root bacteria) is a major source of new nitrogen for land ecosystems(1). A long-standing puzzle(2) is that trees capable of nitrogen fixation are abundant in nitrogen-rich tropical forests, but absent or restricted to early successional stages in nitrogen-poor extra-tropical forests. This biome-scale pattern presents an evolutionary paradox(3), given that the physiological cost(4) of nitrogen fixation predicts the opposite pattern: fixers should be out-competed by non-fixers in nitrogen-rich conditions, but competitively superior in nitrogen-poor soils. Here we evaluate whether this paradox can be explained by the existence of different fixation strategies in tropical versus extra-tropical trees: facultative fixers (capable of downregulating fixation(5,6) by sanctioning mutualistic bacteria(7)) are common in the tropics, whereas obligate fixers (less able to downregulate fixation) dominate at higher latitudes. Using a game-theoretic approach, we assess the ecological and evolutionary conditions under which these fixation strategies emerge, and examine their dependence on climate-driven differences in the nitrogen cycle. We show that in the tropics, transient soil nitrogen deficits following disturbance and rapid tree growth favour a facultative strategy and the coexistence of fixers and non-fixers. In contrast, sustained nitrogen deficits following disturbance in extra-tropical forests favour an obligate fixation strategy, and cause fixers to be excluded in late successional stages. We conclude that biome-scale differences in the abundance of nitrogen fixers can be explained by the interaction between individual plant strategies and climatic constraints on the nitrogen cycle over evolutionary time.

  13. Soil, water, and nutrient losses from management alternatives for degraded pasture in Brazilian Atlantic Rainforest biome.

    Science.gov (United States)

    Rocha Junior, Paulo Roberto da; Andrade, Felipe Vaz; Mendonça, Eduardo de Sá; Donagemma, Guilherme Kangussú; Fernandes, Raphael Bragança Alves; Bhattharai, Rabin; Kalita, Prasanta Kumar

    2017-04-01

    The objective of this study was to evaluate sediment, water and nutrient losses from different pasture managements in the Atlantic Rainforest biome. A field study was carried out in Alegre Espiríto Santo, Brazil, on a Xanthic Ferralsol cultivated with braquiaria (Brachiaria brizantha). The six pasture managements studied were: control (CON), chisel (CHI), fertilizer (FER), burned (BUR), plowing and harrowing (PH), and integrated crop-livestock (iCL). Runoff and sediment samples were collected and analyzed for calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P) and organic carbon contents. Soil physical attributes and above and below biomass were also evaluated. The results indicated that higher water loss was observed for iCL (129.90mm) and CON (123.25mm) managements, and the sediment losses were higher for CON (10.24tha -1 ) and BUR (5.20tha -1 ) managements when compared to the other managements. Majority of the nutrients losses occurred in dissolved fraction (99% of Ca, 99% of Mg, 96% of K, and 65% of P), whereas a significant fraction of organic carbon (80%) loss occurred in a particulate form. Except for P, other nutrients (Ca, Mg and K) and organic carbon losses were higher in coarse sediment compared to fine sediment. The greater losses of sediment, organic carbon, and nutrients were observed for CON followed by BUR management (plosses from various practices, to reduce pasture degradation, farmers should adopt edaphic practices by applying lime and fertilize to improve pasture growth and soil cover, and reducing soil erosion in the hilly Brazilian Atlantic Rainforest biome. Copyright © 2016. Published by Elsevier B.V.

  14. The role of plant functional trade-offs for biodiversity changes and biome shifts under scenarios of global climatic change

    Directory of Open Access Journals (Sweden)

    B. Reu

    2011-05-01

    Full Text Available The global geographic distribution of biodiversity and biomes is determined by species-specific physiological tolerances to climatic constraints. Current vegetation models employ empirical bioclimatic relationships to predict present-day vegetation patterns and to forecast biodiversity changes and biome shifts under climatic change. In this paper, we consider trade-offs in plant functioning and their responses under climatic changes to forecast and explain changes in plant functional richness and shifts in biome geographic distributions.

    The Jena Diversity model (JeDi simulates plant survival according to essential plant functional trade-offs, including ecophysiological processes such as water uptake, photosynthesis, allocation, reproduction and phenology. We use JeDi to quantify changes in plant functional richness and biome shifts between present-day and a range of possible future climates from two SRES emission scenarios (A2 and B1 and seven global climate models using metrics of plant functional richness and functional identity.

    Our results show (i a significant loss of plant functional richness in the tropics, (ii an increase in plant functional richness at mid and high latitudes, and (iii a pole-ward shift of biomes. While these results are consistent with the findings of empirical approaches, we are able to explain them in terms of the plant functional trade-offs involved in the allocation, metabolic and reproduction strategies of plants. We conclude that general aspects of plant physiological tolerances can be derived from functional trade-offs, which may provide a useful process- and trait-based alternative to bioclimatic relationships. Such a mechanistic approach may be particularly relevant when addressing vegetation responses to climatic changes that encounter novel combinations of climate parameters that do not exist under contemporary climate.

  15. The GAAS metagenomic tool and its estimations of viral and microbial average genome size in four major biomes.

    Science.gov (United States)

    Angly, Florent E; Willner, Dana; Prieto-Davó, Alejandra; Edwards, Robert A; Schmieder, Robert; Vega-Thurber, Rebecca; Antonopoulos, Dionysios A; Barott, Katie; Cottrell, Matthew T; Desnues, Christelle; Dinsdale, Elizabeth A; Furlan, Mike; Haynes, Matthew; Henn, Matthew R; Hu, Yongfei; Kirchman, David L; McDole, Tracey; McPherson, John D; Meyer, Folker; Miller, R Michael; Mundt, Egbert; Naviaux, Robert K; Rodriguez-Mueller, Beltran; Stevens, Rick; Wegley, Linda; Zhang, Lixin; Zhu, Baoli; Rohwer, Forest

    2009-12-01

    Metagenomic studies characterize both the composition and diversity of uncultured viral and microbial communities. BLAST-based comparisons have typically been used for such analyses; however, sampling biases, high percentages of unknown sequences, and the use of arbitrary thresholds to find significant similarities can decrease the accuracy and validity of estimates. Here, we present Genome relative Abundance and Average Size (GAAS), a complete software package that provides improved estimates of community composition and average genome length for metagenomes in both textual and graphical formats. GAAS implements a novel methodology to control for sampling bias via length normalization, to adjust for multiple BLAST similarities by similarity weighting, and to select significant similarities using relative alignment lengths. In benchmark tests, the GAAS method was robust to both high percentages of unknown sequences and to variations in metagenomic sequence read lengths. Re-analysis of the Sargasso Sea virome using GAAS indicated that standard methodologies for metagenomic analysis may dramatically underestimate the abundance and importance of organisms with small genomes in environmental systems. Using GAAS, we conducted a meta-analysis of microbial and viral average genome lengths in over 150 metagenomes from four biomes to determine whether genome lengths vary consistently between and within biomes, and between microbial and viral communities from the same environment. Significant differences between biomes and within aquatic sub-biomes (oceans, hypersaline systems, freshwater, and microbialites) suggested that average genome length is a fundamental property of environments driven by factors at the sub-biome level. The behavior of paired viral and microbial metagenomes from the same environment indicated that microbial and viral average genome sizes are independent of each other, but indicative of community responses to stressors and environmental conditions.

  16. The GAAS metagenomic tool and its estimations of viral and microbial average genome size in four major biomes.

    Directory of Open Access Journals (Sweden)

    Florent E Angly

    2009-12-01

    Full Text Available Metagenomic studies characterize both the composition and diversity of uncultured viral and microbial communities. BLAST-based comparisons have typically been used for such analyses; however, sampling biases, high percentages of unknown sequences, and the use of arbitrary thresholds to find significant similarities can decrease the accuracy and validity of estimates. Here, we present Genome relative Abundance and Average Size (GAAS, a complete software package that provides improved estimates of community composition and average genome length for metagenomes in both textual and graphical formats. GAAS implements a novel methodology to control for sampling bias via length normalization, to adjust for multiple BLAST similarities by similarity weighting, and to select significant similarities using relative alignment lengths. In benchmark tests, the GAAS method was robust to both high percentages of unknown sequences and to variations in metagenomic sequence read lengths. Re-analysis of the Sargasso Sea virome using GAAS indicated that standard methodologies for metagenomic analysis may dramatically underestimate the abundance and importance of organisms with small genomes in environmental systems. Using GAAS, we conducted a meta-analysis of microbial and viral average genome lengths in over 150 metagenomes from four biomes to determine whether genome lengths vary consistently between and within biomes, and between microbial and viral communities from the same environment. Significant differences between biomes and within aquatic sub-biomes (oceans, hypersaline systems, freshwater, and microbialites suggested that average genome length is a fundamental property of environments driven by factors at the sub-biome level. The behavior of paired viral and microbial metagenomes from the same environment indicated that microbial and viral average genome sizes are independent of each other, but indicative of community responses to stressors and

  17. Central tendency and variability in biological systems

    Directory of Open Access Journals (Sweden)

    Lucien J. Cardinal

    2015-06-01

    Full Text Available In this article, the author reviews the manner in which researchers characterize data. Normality, standard deviation, mean, and other concepts related to parametric statistics are discussed in common language, with a minimum of jargon and with clinical examples.

  18. The Central Dogma of Molecular Biology

    Indian Academy of Sciences (India)

    Srimath

    Since that tim e,m any disciplines have m im icked ... of religion, he considered dogm as sim ply as bold hy- p oth eses ... Form any students,now fam iliarw ith the C entralD ogm a since their ..... m olecules,R N A s and proteins,existed initially,and D N A .... B J Strasser, A world in one dimension: Linus Pauling, Francis Crick.

  19. 7th Annual Systems Biology Symposium: Systems Biology and Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Galitski, Timothy P.

    2008-04-01

    Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology has been hosted by the Institute for Systems Biology in Seattle, Washington, since 2002. The annual two-day event gathers the most influential researchers transforming biology into an integrative discipline investingating complex systems. Engineering and application of new technology is a central element of systems biology. Genome-scale, or very small-scale, biological questions drive the enigneering of new technologies, which enable new modes of experimentation and computational analysis, leading to new biological insights and questions. Concepts and analytical methods in engineering are now finding direct applications in biology. Therefore, the 2008 Symposium, funded in partnership with the Department of Energy, featured global leaders in "Systems Biology and Engineering."

  20. Vida saudável versus vida aprimorada: tecnologias biomédicas, processos de subjetivação e aprimoramento

    Directory of Open Access Journals (Sweden)

    Fabíola Rohden

    Full Text Available Resumo Fenômenos contemporâneos como um crescimento significativo dos campos da medicina sexual e da medicina estética exigem novas investigações empíricas e também aprofundamento de determinados debates teóricos. No contexto das últimas décadas, ganham relevo formas de subjetivação centradas no investimento pessoal via transformações corporais, nas quais o consumo de artefatos biomédicos considerados inovadores torna-se central. Em função da produção de questões advindas desse campo, este artigo discute criticamente alguns vetores conceituais. Categorias analíticas como biomedicalização, farmacologização, modos de subjetivação e aprimoramento são centrais para dar conta de entender os processos em questão. Na mesma direção, é preciso considerar a importância de problematizar as fronteiras entre os investimentos associados à manutenção da saúde e aqueles motivados pelo aprimoramento de si.

  1. Euclea undulata Thunb.: Review of its botany, ethnomedicinal uses, phytochemistry and biological activities.

    Science.gov (United States)

    Maroyi, Alfred

    2017-11-01

    Euclea undulata (E. undulata) is traditionally used for the treatment of body pains, chest complaints, cough, diabetes, diarrhoea, headaches, heart diseases and toothaches in southern Africa. This study was aimed at reviewing the botany, ethnopharmacology and biological activities of E. undulata in southern Africa. Results presented in this study are based on review of literature using search engines such as Science Direct, Springerlink, Scopus, PubMed, Web of Science, BioMed Central and Google Scholar. Herbal medicine is prepared from the decoctions of the roots, bark and leaves, and extracts of these plant parts have demonstrated anticholinesterase, anti-inflammatory, antimicrobial, antimycobacterial, antiplasmodial, antioxidant and hypoglycaemic activities. Multiple classes of phytochemical compounds such alkaloids, diterpenes, fatty acids, flavonoids, glycosides, naphthoquinones, phenolics, phytosterols, reducing sugars, saponins and tannins have been isolated from the species. E. undulata has a lot of potential as herbal medicine in tropical Africa, and advanced research is required aimed at correlating its medicinal uses with the phytochemistry and pharmacological properties. Copyright © 2017 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

  2. Sensibility and time heterogeneity of Biome-BGC model parameters%Biome-BGC模型参数的敏感性和时间异质性

    Institute of Scientific and Technical Information of China (English)

    刘秋雨; 张廷龙; 孙睿; 王博闻; 叶欣欣; 李一哲

    2017-01-01

    生态过程模型为研究陆表生态系统水、碳、氮等物质的循环提供了一种有效的手段.模型与数据同化结合可建立模拟与观测之间的桥梁,同时提高模型与观测两种方法揭示地表真实状况的有效性.但模型参数的特性,将直接影响到模型模拟及数据同化的精度.传统观念认为,生态过程模型参数在相同植被类型条件下是固定不变的,但近期研究已开始关注其时空异质性.本文以Biome-BGC模型为例,利用美国哈佛森林Environmental Monitoring Site (EMS)通量观测站的相关数据,对哈佛森林地区水、碳通量进行模拟.首先对模型参数进行敏感性分析;然后应用模拟退火算法,构造目标函数,使待优化的敏感参数在合理阈值范围内不断变动反复迭代,获取逐月的最优参数值;通过引入变异系数,对敏感参数的时间异质性进行分析.结果表明:生态过程模型参数最优值并非常量,而会随时间表现出异质性,而且各参数时间异质性大小差异显著.文中对Biome-BGC模型的敏感参数按时间异质性大小划分了相应的等级.研究结果有助于加深对生态过程模型参数特性的认识,为参数的合理取值及动态优化提供思路与依据,有助于进一步提高模型模拟和数据同化的精度与效率.%Ecological process model provides an effective way for studying water,carbon and nitrogen cycles of terrestrial ecosystem.The combination of the model and data assimilation could build a link between observation and simulation,which improves the effectiveness of model and observation methods to reveal the real state of land surface,but the accuracy of simulation and assimilation is directly affected by model parameters.Parameters are constants in traditional opinion;however,some current studies have focused on the time-space heterogeneity of parameters.In this paper,we used Harvard Forest Environmental Monitoring Site (EMS) data to simulate

  3. Modeling the grazing effect on dry grassland carbon cycling with modified Biome-BGC grazing model

    Science.gov (United States)

    Luo, Geping; Han, Qifei; Li, Chaofan; Yang, Liao

    2014-05-01

    Identifying the factors that determine the carbon source/sink strength of ecosystems is important for reducing uncertainty in the global carbon cycle. Arid grassland ecosystems are a widely distributed biome type in Xinjiang, Northwest China, covering approximately one-fourth the country's land surface. These grasslands are the habitat for many endemic and rare plant and animal species and are also used as pastoral land for livestock. Using the modified Biome-BGC grazing model, we modeled carbon dynamics in Xinjiang for grasslands that varied in grazing intensity. In general, this regional simulation estimated that the grassland ecosystems in Xinjiang acted as a net carbon source, with a value of 0.38 Pg C over the period 1979-2007. There were significant effects of grazing on carbon dynamics. An over-compensatory effect in net primary productivity (NPP) and vegetation carbon (C) stock was observed when grazing intensity was lower than 0.40 head/ha. Grazing resulted in a net carbon source of 23.45 g C m-2 yr-1, which equaled 0.37 Pg in Xinjiang in the last 29 years. In general, grazing decreased vegetation C stock, while an increasing trend was observed with low grazing intensity. The soil C increased significantly (17%) with long-term grazing, while the soil C stock exhibited a steady trend without grazing. These findings have implications for grassland ecosystem management as it relates to carbon sequestration and climate change mitigation, e.g., removal of grazing should be considered in strategies that aim to increase terrestrial carbon sequestrations at local and regional scales. One of the greatest limitations in quantifying the effects of herbivores on carbon cycling is identifying the grazing systems and intensities within a given region. We hope our study emphasizes the need for large-scale assessments of how grazing impacts carbon cycling. Most terrestrial ecosystems in Xinjiang have been affected by disturbances to a greater or lesser extent in the past

  4. Future projections of fire danger in Brazilian biomes in the 21st century

    Science.gov (United States)

    Libonati, Renata; Silva, Patrícia; DaCamara, Carlos; Bastos, Ana

    2016-04-01

    In the global context, Brazil is one of the regions more severely affected by fire occurrences, with important consequences in the global CO2 balance, the state of the Amazon forest and the ecological diversity of the region. Brazil is also one of the few regions experiencing a raise in annual mean temperature above 2.5o during the 20th century, which may further increase between 2o and 7o until 2100 and, likely, be accompanied by a decrease in precipitation [1]. As the fire occurrence and severity largely depends on these two variables, it is worth assessing the evolution of fire danger for the coming decades. In order to obtain a detailed characterization of the future fire patterns in the different biomes of Brazil, we use outputs from a regional-downscaling of the EC-Earth climate model at 0.44 degrees spatial resolution for two future scenarios, an intermediate (RCP4.5) and a more severe (RCP8.5) one. We use a fire danger index specifically developed for the Brazilian climate and biome characteristics, the IFR from INPE. This index relies on values of maximum temperature, accumulated precipitation over different periods, minimum relative humidity and vegetation cover to estimate the likelihood of fire occurrence. We find a systematic increase of the days with critical fire risk, which is more pronounced in RCP8.5 and mostly affects months when fire activity takes place. Temperature increase is the most determinant factor for the increase in fire danger in the dry regions of savannah and shrubland, a result to be expected as fuel is already very dry. [1] Collins, M., R. Knutti, J. Arblaster, J.-L. Dufresne, T. Fichefet, P. Friedlingstein, X. Gao, W.J. Gutowski, T. Johns, G. Krinner, M. Shongwe, C. Tebaldi, A.J. Weaver and M. Wehner, 2013: Long-term Climate Change: Projections, Commitments and Irreversibility. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on

  5. Structure of Drosophilidae Assemblage (Insecta, Diptera in Pampa Biome (São Luiz Gonzaga, RS

    Directory of Open Access Journals (Sweden)

    Jean Lucas Poppe

    2012-01-01

    Full Text Available The Brazilian Pampa (the southernmost end of the country is currently a highly modified environment because of increasing agricultural activities. In many places, only small parts of grasslands remain inside an agricultural landscape. Drosophilidae (Diptera have been widely used as a potential bioindicators to monitor the effects of anthropogenic changes in natural environments. However, the fauna of Drosophilidae in the Pampa Biome from natural and disturbed environments, still remains largely unknown. The present study represents one of the first attempts to fill this gap, showing results from monthly collections in the municipality of São Luiz Gonzaga (28º24'28"S, 54º57'39"W, in the Brazilian Pampa. A species inventory was carried out in two contrasting environments, an urban zone and a forest remnant (rural zone. In both areas banana-baited traps were used to capture adult drosophilids. The identification was made using external morphology and male terminalia. In total, 13,379 drosophilids were analyzed (rural zone: N = 8,812 and Sobs = 25; urban zone: N = 4,567 and Sobs = 16. In the present study, 16 (60% out of 26 species were found exclusively or preferentially in the forest. The period of highest richness was between the months of June to November (roughly winter and spring, and the period of lowest richness was from December to May (roughly summer and autumn. An analysis of cluster by the Coefficient of Jaccard showed that species composition slightly changes when the period of the year with higher temperatures (from January to May is compared with the period with lower temperatures (from June to October. The species abundances were also highly affected by seasonality, as revealed by the Morisita Index, since the samples clustered into similar groups in consecutive periods and in the same season, showing the seasonal preference of some species. The time component was a determinant in the diversity of the assemblage, surpassing the

  6. Biological Agents

    Science.gov (United States)

    ... E-Tools Safety and Health Topics / Biological Agents Biological Agents This page requires that javascript be enabled ... 202) 693-2300 if additional assistance is required. Biological Agents Menu Overview In Focus: Ebola Frederick A. ...

  7. Plant litter dynamics in the forest-stream interface: precipitation is a major control across tropical biomes

    OpenAIRE

    Tonin, Alan M.; Gon?alves, Jos? F.; Bambi, Paulino; Couceiro, Sheyla R. M.; Feitoza, Lorrane A. M.; Fontana, Lucas E.; Hamada, Neusa; Hepp, Luiz U.; Lezan-Kowalczuk, V?nia G.; Leite, Gustavo F. M.; Lemes-Silva, Aurea L.; Lisboa, Leonardo K.; Loureiro, Rafael C.; Martins, Renato T.; Medeiros, Adriana O.

    2017-01-01

    Riparian plant litter is a major energy source for forested streams across the world and its decomposition has repercussions on nutrient cycling, food webs and ecosystem functioning. However, we know little about plant litter dynamics in tropical streams, even?though the tropics occupy 40% of the Earth?s land surface. Here we investigated spatial and temporal (along a year cycle) patterns of litter inputs and storage in multiple streams of three tropical biomes in Brazil (Atlantic forest, Ama...

  8. [Parameter sensitivity of simulating net primary productivity of Larix olgensis forest based on BIOME-BGC model].

    Science.gov (United States)

    He, Li-hong; Wang, Hai-yan; Lei, Xiang-dong

    2016-02-01

    Model based on vegetation ecophysiological process contains many parameters, and reasonable parameter values will greatly improve simulation ability. Sensitivity analysis, as an important method to screen out the sensitive parameters, can comprehensively analyze how model parameters affect the simulation results. In this paper, we conducted parameter sensitivity analysis of BIOME-BGC model with a case study of simulating net primary productivity (NPP) of Larix olgensis forest in Wangqing, Jilin Province. First, with the contrastive analysis between field measurement data and the simulation results, we tested the BIOME-BGC model' s capability of simulating the NPP of L. olgensis forest. Then, Morris and EFAST sensitivity methods were used to screen the sensitive parameters that had strong influence on NPP. On this basis, we also quantitatively estimated the sensitivity of the screened parameters, and calculated the global, the first-order and the second-order sensitivity indices. The results showed that the BIOME-BGC model could well simulate the NPP of L. olgensis forest in the sample plot. The Morris sensitivity method provided a reliable parameter sensitivity analysis result under the condition of a relatively small sample size. The EFAST sensitivity method could quantitatively measure the impact of simulation result of a single parameter as well as the interaction between the parameters in BIOME-BGC model. The influential sensitive parameters for L. olgensis forest NPP were new stem carbon to new leaf carbon allocation and leaf carbon to nitrogen ratio, the effect of their interaction was significantly greater than the other parameter' teraction effect.

  9. Comment on Chiesi et al. (2011): “Use of BIOME-BGC to simulate Mediterranean forest carbon stocks”

    OpenAIRE

    Eastaugh CS

    2011-01-01

    The mechanistic forest growth model BIOME-BGC utilizes a “spin-up” procedure to estimate site parameters for forests in a steady-state condition, as they may have been expected to be prior to anthropogenic influence. Forests in this condition have no net growth, as living biomass accumulation is balanced by mortality. To simulate current ecosystems it is necessary to reset the model to reflect a forest of the correct development stage. The alternative approach of simply post-adjus...

  10. Soil Loss Vulnerability in an Agricultural Catchment in the Atlantic Forest Biome in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Rafael Gotardo

    2016-11-01

    Full Text Available This study estimates soil loss vulnerability using field samples and spatial data in a 30 km² area in the Atlantic forest biome in southern Brazil. The anthropogenic part of the landscape consists mainly of small agricultural properties. Soil loss vulnerability was calculated using adaptations of the universal soil loss equation. The results were compared to sediment data collected during field surveys. Spatial analysis was performed using a geographical information system (GIS and fine resolution data (1 m. Both field and spatial analyses produced similar results, 5.390 tons of soil loss per year using field data and 5.691 tons per year using GIS. Using soil loss and sediment data related to the Concordia River, we estimate that of all the exported sediment 25% of the lost soil reaches the river. These data are an effective source of information for municipal administrators of the region, which consists of small agricultural catchments (dominated by small properties that comprise the regional economy. A thematic map was used to determine sub-drainage priority as information for public managers.

  11. Plants of the fynbos biome harbour host species-specific bacterial communities.

    Science.gov (United States)

    Miyambo, Tsakani; Makhalanyane, Thulani P; Cowan, Don A; Valverde, Angel

    2016-08-01

    The fynbos biome in South Africa is globally recognised as a plant biodiversity hotspot. However, very little is known about the bacterial communities associated with fynbos plants, despite interactions between primary producers and bacteria having an impact on the physiology of both partners and shaping ecosystem diversity. This study reports on the structure, phylogenetic composition and potential roles of the endophytic bacterial communities located in the stems of three fynbos plants (Erepsia anceps, Phaenocoma prolifera and Leucadendron laureolum). Using Illumina MiSeq 16S rRNA sequencing we found that different subpopulations of Deinococcus-Thermus, Alphaproteobacteria, Acidobacteria and Firmicutes dominated the endophytic bacterial communities. Alphaproteobacteria and Actinobacteria were prevalent in P. prolifera, whereas Deinococcus-Thermus dominated in L. laureolum, revealing species-specific host-bacteria associations. Although a high degree of variability in the endophytic bacterial communities within hosts was observed, we also detected a core microbiome across the stems of the three plant species, which accounted for 72% of the sequences. Altogether, it seems that both deterministic and stochastic processes shaped microbial communities. Endophytic bacterial communities harboured putative plant growth-promoting bacteria, thus having the potential to influence host health and growth. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Soil-borne bacterial structure and diversity does not reflect community activity in Pampa biome.

    Science.gov (United States)

    Lupatini, Manoeli; Suleiman, Afnan Khalil Ahmad; Jacques, Rodrigo Josemar Seminoti; Antoniolli, Zaida Inês; Kuramae, Eiko Eurya; de Oliveira Camargo, Flávio Anastácio; Roesch, Luiz Fernando Würdig

    2013-01-01

    The Pampa biome is considered one of the main hotspots of the world's biodiversity and it is estimated that half of its original vegetation was removed and converted to agricultural land and tree plantations. Although an increasing amount of knowledge is being assembled regarding the response of soil bacterial communities to land use change, to the associated plant community and to soil properties, our understanding about how these interactions affect the microbial community from the Brazilian Pampa is still poor and incomplete. In this study, we hypothesized that the same soil type from the same geographic region but under distinct land use present dissimilar soil bacterial communities. To test this hypothesis, we assessed the soil bacterial communities from four land-uses within the same soil type by 454-pyrosequencing of 16S rRNA gene and by soil microbial activity analyzes. We found that the same soil type under different land uses harbor similar (but not equal) bacterial communities and the differences were controlled by many microbial taxa. No differences regarding diversity and richness between natural areas and areas under anthropogenic disturbance were detected. However, the measures of microbial activity did not converge with the 16S rRNA data supporting the idea that the coupling between functioning and composition of bacterial communities is not necessarily correlated.

  13. Local climatic conditions constrain soil yeast diversity patterns in Mediterranean forests, woodlands and scrub biome.

    Science.gov (United States)

    Yurkov, Andrey M; Röhl, Oliver; Pontes, Ana; Carvalho, Cláudia; Maldonado, Cristina; Sampaio, José Paulo

    2016-02-01

    Soil yeasts represent a poorly known fraction of the soil microbiome due to limited ecological surveys. Here, we provide the first comprehensive inventory of cultivable soil yeasts in a Mediterranean ecosystem, which is the leading biodiversity hotspot for vascular plants and vertebrates in Europe. We isolated and identified soil yeasts from forested sites of Serra da Arrábida Natural Park (Portugal), representing the Mediterranean forests, woodlands and scrub biome. Both cultivation experiments and the subsequent species richness estimations suggest the highest species richness values reported to date, resulting in a total of 57 and 80 yeast taxa, respectively. These values far exceed those reported for other forest soils in Europe. Furthermore, we assessed the response of yeast diversity to microclimatic environmental factors in biotopes composed of the same plant species but showing a gradual change from humid broadleaf forests to dry maquis. We observed that forest properties constrained by precipitation level had strong impact on yeast diversity and on community structure and lower precipitation resulted in an increased number of rare species and decreased evenness values. In conclusion, the structure of soil yeast communities mirrors the environmental factors that affect aboveground phytocenoses, aboveground biomass and plant projective cover. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. A multi-biome gap in understanding of crop and ecosystem responses to elevated CO2.

    Science.gov (United States)

    Leakey, Andrew D B; Bishop, Kristen A; Ainsworth, Elizabeth A

    2012-06-01

    A key finding from elevated [CO(2)] field experiments is that the impact of elevated [CO(2)] on plant and ecosystem function is highly dependent upon other environmental conditions, namely temperature and the availability of nutrients and soil moisture. In addition, there is significant variation in the response to elevated [CO(2)] among plant functional types, species and crop varieties. However, experimental data on plant and ecosystem responses to elevated [CO(2)] are strongly biased to economically and ecologically important systems in the temperate zone. There is a multi-biome gap in experimental data that is most severe in the tropics and subtropics, but also includes high latitudes. Physiological understanding of the environmental conditions and species found at high and low latitudes suggest they may respond differently to elevated [CO(2)] than well-studied temperate systems. Addressing this knowledge gap should be a high priority as it is vital to understanding 21st century food supply and ecosystem feedbacks on climate change. Published by Elsevier Ltd.

  15. Predicting the responsiveness of soil biodiversity to deforestation: a cross-biome study.

    Science.gov (United States)

    Crowther, Thomas W; Maynard, Daniel S; Leff, Jonathan W; Oldfield, Emily E; McCulley, Rebecca L; Fierer, Noah; Bradford, Mark A

    2014-09-01

    The consequences of deforestation for aboveground biodiversity have been a scientific and political concern for decades. In contrast, despite being a dominant component of biodiversity that is essential to the functioning of ecosystems, the responses of belowground biodiversity to forest removal have received less attention. Single-site studies suggest that soil microbes can be highly responsive to forest removal, but responses are highly variable, with negligible effects in some regions. Using high throughput sequencing, we characterize the effects of deforestation on microbial communities across multiple biomes and explore what determines the vulnerability of microbial communities to this vegetative change. We reveal consistent directional trends in the microbial community response, yet the magnitude of this vegetation effect varied between sites, and was explained strongly by soil texture. In sandy sites, the difference in vegetation type caused shifts in a suite of edaphic characteristics, driving substantial differences in microbial community composition. In contrast, fine-textured soil buffered microbes against these effects and there were minimal differences between communities in forest and grassland soil. These microbial community changes were associated with distinct changes in the microbial catabolic profile, placing community changes in an ecosystem functioning context. The universal nature of these patterns allows us to predict where deforestation will have the strongest effects on soil biodiversity, and how these effects could be mitigated. © 2014 John Wiley & Sons Ltd.

  16. SOIL ORGANIC MATTER FRACTIONS IN PRESERVED AND DISTURBED WETLANDS OF THE CERRADO BIOME

    Directory of Open Access Journals (Sweden)

    Ricardo Fernandes de Sousa

    2015-02-01

    Full Text Available Veredas are humid tropical ecosystems, generally associated to hydromorphic soils and a shallow water table. The soils of these ecosystems are affected by the use of the areas around these veredas. The objective of this study was to determine soil organic matter (SOM fractions in veredas adjacent to preserved (native savanna and disturbed environments (agricultural areas and pastures in the Cerrado biome. Soil samples were collected from the 0-10 and 10-20 cm layers along reference lines drawn along the relief following the upper, middle and lower positions of one of the slopes, in the direction of the draining line of the vereda. The soil analysis determined: total soil OC, total nitrogen and C:N ratio; C and N contents and C:N ratio in particulate and mineral-associated fractions (of SOM; fulvic acids, humic acids and humin fractions and ratio between humic and fulvic acids. The agricultural use around the veredas induced changes in the SOM fractions, more pronounced in the lower part of the slope. In the soil surface of this part, the OC levels in the humic substances and the particulate fraction of SOM, as well as total soil OC were reduced in the vereda next to crop fields.

  17. Introducing BASE: the Biomes of Australian Soil Environments soil microbial diversity database.

    Science.gov (United States)

    Bissett, Andrew; Fitzgerald, Anna; Meintjes, Thys; Mele, Pauline M; Reith, Frank; Dennis, Paul G; Breed, Martin F; Brown, Belinda; Brown, Mark V; Brugger, Joel; Byrne, Margaret; Caddy-Retalic, Stefan; Carmody, Bernie; Coates, David J; Correa, Carolina; Ferrari, Belinda C; Gupta, Vadakattu V S R; Hamonts, Kelly; Haslem, Asha; Hugenholtz, Philip; Karan, Mirko; Koval, Jason; Lowe, Andrew J; Macdonald, Stuart; McGrath, Leanne; Martin, David; Morgan, Matt; North, Kristin I; Paungfoo-Lonhienne, Chanyarat; Pendall, Elise; Phillips, Lori; Pirzl, Rebecca; Powell, Jeff R; Ragan, Mark A; Schmidt, Susanne; Seymour, Nicole; Snape, Ian; Stephen, John R; Stevens, Matthew; Tinning, Matt; Williams, Kristen; Yeoh, Yun Kit; Zammit, Carla M; Young, Andrew

    2016-01-01

    Microbial inhabitants of soils are important to ecosystem and planetary functions, yet there are large gaps in our knowledge of their diversity and ecology. The 'Biomes of Australian Soil Environments' (BASE) project has generated a database of microbial diversity with associated metadata across extensive environmental gradients at continental scale. As the characterisation of microbes rapidly expands, the BASE database provides an evolving platform for interrogating and integrating microbial diversity and function. BASE currently provides amplicon sequences and associated contextual data for over 900 sites encompassing all Australian states and territories, a wide variety of bioregions, vegetation and land-use types. Amplicons target bacteria, archaea and general and fungal-specific eukaryotes. The growing database will soon include metagenomics data. Data are provided in both raw sequence (FASTQ) and analysed OTU table formats and are accessed via the project's data portal, which provides a user-friendly search tool to quickly identify samples of interest. Processed data can be visually interrogated and intersected with other Australian diversity and environmental data using tools developed by the 'Atlas of Living Australia'. Developed within an open data framework, the BASE project is the first Australian soil microbial diversity database. The database will grow and link to other global efforts to explore microbial, plant, animal, and marine biodiversity. Its design and open access nature ensures that BASE will evolve as a valuable tool for documenting an often overlooked component of biodiversity and the many microbe-driven processes that are essential to sustain soil function and ecosystem services.

  18. PERMANENCE OF WATER EFFECTIVENESS IN THE ROOT ZONE OF THE CAATINGA BIOME

    Directory of Open Access Journals (Sweden)

    CARLOS ALEXANDRE GOMES COSTA

    2016-01-01

    Full Text Available Soil is an important water compartment into a watershed scale, mainly due to its role in providing water to plants and to the influence of antecedent moisture on the runoff initiation. The aim of this research is to assess the permanence of water effectiveness in the soil under preserved-vegetation constraints in the Caatinga biome, in the semiarid northeastern Brazil. For this purpose, hourly soil moisture measurements were collected with TDR and analyzed between 2003 and 2010 for three soil-vegetation associations in the Aiuaba Experimental Basin. The results showed that in nine months per year soil moisture was below wilting point for two associations, whose soils are Chromic Luvisol and Haplic Lixisol (Abruptic. In the third association, where the shallow soil Lithic Leptosol prevails, water was found non-effective four months per year. A possible reason for the high water permanence in the shallowest soil is the percolation process, generating sub-surface flow, which barely occurs in the deeper soils. In situ observations indicates that the long period of soil moisture below the wilting point was not enough to avoid the blooming season of the Caatinga vegetation during the rainy periods. Indeed, after the beginning of each rainy season, there is a growth of dense green vegetation, regardless of the long period under water shortage.

  19. Diversity of herbaceous plants and bacterial communities regulates soil resistome across forest biomes.

    Science.gov (United States)

    Hu, Hang-Wei; Wang, Jun-Tao; Singh, Brajesh K; Liu, Yu-Rong; Chen, Yong-Liang; Zhang, Yu-Jing; He, Ji-Zheng

    2018-04-24

    Antibiotic resistance is ancient and prevalent in natural ecosystems and evolved long before the utilization of synthetic antibiotics started, but factors influencing the large-scale distribution patterns of natural antibiotic resistance genes (ARGs) remain largely unknown. Here, a large-scale investigation over 4000 km was performed to profile soil ARGs, plant communities and bacterial communities from 300 quadrats across five forest biomes with minimal human impact. We detected diverse and abundant ARGs in forests, including over 160 genes conferring resistance to eight major categories of antibiotics. The diversity of ARGs was strongly and positively correlated with the diversity of bacteria, herbaceous plants and mobile genetic elements (MGEs). The ARG composition was strongly correlated with the taxonomic structure of bacteria and herbs. Consistent with this strong correlation, structural equation modelling demonstrated that the positive effects of bacterial and herb communities on ARG patterns were maintained even when simultaneously accounting for multiple drivers (climate, spatial predictors and edaphic factors). These findings suggest a paradigm that the interactions between aboveground and belowground communities shape the large-scale distribution of soil resistomes, providing new knowledge for tackling the emerging environmental antibiotic resistance. © 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.

  20. Microbial quality of soil from the Pampa biome in response to different grazing pressures

    Directory of Open Access Journals (Sweden)

    Rafael S. Vargas

    2015-06-01

    Full Text Available The aim of this study was to evaluate the impact of different grazing pressures on the activity and diversity of soil bacteria. We performed a long-term experiment in Eldorado do Sul, southern Brazil, that assessed three levels of grazing pressure: high pressure (HP, with 4% herbage allowance (HA, moderate pressure (MP, with 12% HA, and low pressure (LP, with 16% HA. Two reference areas were also assessed, one of never-grazed native vegetation (NG and another of regenerated vegetation after two years of grazing (RG. Soil samples were evaluated for microbial biomass and enzymatic (β-glucosidase, arylsulfatase and urease activities. The structure of the bacterial community and the population of diazotrophic bacteria were evaluated by RFLP of the 16S rRNA and nifH genes, respectively. The diversity of diazotrophic bacteria was assessed by partial sequencing of the 16S rDNA gene. The presence of grazing animals increased soil microbial biomass in MP and HP. The structures of the bacterial community and the populations of diazotrophic bacteria were altered by the different grazing managements, with a greater diversity of diazotrophic bacteria in the LP treatment. Based on the characteristics evaluated, the MP treatment was the most appropriate for animal production and conservation of the Pampa biome.

  1. Termite assemblages in five semideciduous Atlantic Forest fragments in the northern coastland limit of the biome

    Directory of Open Access Journals (Sweden)

    Heitor Bruno de Araújo Souza

    2012-03-01

    Full Text Available Termites are abundant organisms in tropical ecosystems and strongly influence the litter decomposition and soil formation. Despite their importance, few studies about their assemblage structures have been made in Brazilian Atlantic Forest fragments, especially in the area located north of the São Francisco River. This study aims to analyze the assemblage composition of five Atlantic Forest fragments located in the northern biome limit along the Brazilian coast. A standardized sampling protocol of termites was applied in each fragment. Thirty-three termite species belonging to twenty genera and three families were found in the forest fragments. The wood-feeder group was dominant both concerning to species richness and number of encounters in all areas. In sites northern to 7°S, there is an evident simplification of the termite assemblage composition regarding species richness and number of encounters by feeding group. This fact is apparently due to a higher sandy level in soils and to semideciduous character of the vegetation in the northern fragments. Thus, even on the north of São Francisco River, termite biodiversity is heterogeneously spread with highest density of species in the portion between 07°S and São Francisco River mouth (10°29'S.

  2. Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes

    Directory of Open Access Journals (Sweden)

    M. Bahn

    2010-07-01

    Full Text Available Soil respiration (SR constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. However, there still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 80 site-years for 57 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SRMAT, irrespective of the type of ecosystem and biome. This is theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10. We further show that for seasonally dry sites where annual precipitation (P is lower than potential evapotranspiration (PET, annual SR can be predicted from wet season SRMAT corrected for a factor related to P/PET. Our finding indicates that it can be sufficient to measure SRMAT for obtaining a well constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatial resolution of a major component of the global carbon cycle.

  3. Beyond aridification: multiple explanations for the elevated diversification of cacti in the New World Succulent Biome.

    Science.gov (United States)

    Hernández-Hernández, Tania; Brown, Joseph W; Schlumpberger, Boris O; Eguiarte, Luis E; Magallón, Susana

    2014-06-01

    Succulent plants are widely distributed, reaching their highest diversity in arid and semi-arid regions. Their origin and diversification is thought to be associated with a global expansion of aridity. We test this hypothesis by investigating the tempo and pattern of Cactaceae diversification. Our results contribute to the understanding of the evolution of New World Succulent Biomes. We use the most taxonomically complete dataset currently available for Cactaceae. We estimate divergence times and utilize Bayesian and maximum likelihood methods that account for nonrandom taxonomic sampling, possible extinction scenarios and phylogenetic uncertainty to analyze diversification rates, and evolution of growth form and pollination syndrome. Cactaceae originated shortly after the Eocene-Oligocene global drop in CO2 , and radiation of its richest genera coincided with the expansion of aridity in North America during the late Miocene. A significant correlation between growth form and pollination syndrome was found, as well as a clear state dependence between diversification rate, and pollination and growth-form evolution. This study suggests a complex picture underlying the diversification of Cactaceae. It not only responded to the availability of new niches resulting from aridification, but also to the correlated evolution of novel growth forms and reproductive strategies. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  4. Effect of postharvest practices including degreening on citrus carpoplane microbial biomes.

    Science.gov (United States)

    Gomba, A; Chidamba, L; Korsten, L

    2017-04-01

    To investigate the effect of commercial citrus packhouse processing steps on the fruit surface microbiome of Clementines and Palmer navel oranges. Viable bacteria, yeast and fungi counts, and the pyrosequencing analysis of the 16S rRNA and ITS were used to evaluate the community structure and population dynamics of phylloepiphytic bacteria and fungi associated with commercial postharvest processing. Drenching significantly reduced microbial counts in all cases except for yeasts on navels, while the extent of degreening effects varied between the citrus varieties. Pyrosequencing analysis showed a total of 4409 bacteria and 5792 fungi nonchimeric unique sequences with an average of 1102 bacteria and 1448 fungi reads per sample. Dominant phyla on the citrus carpoplane were Proteobacteria (53·5%), Actinobacteria (19·9%), Bacteroidetes (5·6%) and Deinococcus-Thermus (5·4%) for bacteria and Ascomycota (80·5%) and Basidiomycota (9·8%) for fungi. Beginning with freshly harvested fruit fungal diversity declined significantly after drenching, but had little effect on bacteria and populations recovered during degreening treatments, including those for Penicillium sp. Packhouse processing greatly influences microbial communities on the citrus carpoplane. A broad orange biome was described with pyrosequencing and gave insight into the likely survival and persistence of pathogens, especially as they may affect the quality and safety of the packed product. A close examination of the microbiota of fruit and the impact of intervention strategies on the ecological balance may provide a more durable approach to reduce losses and spoilage. © 2017 The Society for Applied Microbiology.

  5. Antimicrobial potential of actinobacteria isolated from the rhizosphere of the Caatinga biome plant Caesalpinia pyramidalis Tul.

    Science.gov (United States)

    Silva-Lacerda, G R; Santana, R C F; Vicalvi-Costa, M C V; Solidônio, E G; Sena, K X F R; Lima, G M S; Araújo, J M

    2016-03-04

    Actinobacteria are known to produce various secondary metabolites having antibiotic effects. This study assessed the antimicrobial potential of actinobacteria isolated from the rhizosphere of Caesalpinia pyramidalis Tul. from the Caatinga biome. Sixty-eight actinobacteria isolates were evaluated for antimicrobial activity against different microorganisms by disk diffusion and submerged fermentation, using different culture media, followed by determination of minimum inhibitory concentration (MIC) and chemical prospecting of the crude extract. Of the isolates studied, 52.9% of those isolated at 37°C and 47.05% of those isolated at 45°C had activity against Bacillus subtilis, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Fusarium moniliforme, and Candida albicans. When compared with others actinobacteria, the isolate C1.129 stood out with better activity and was identified by 16S rDNA gene analysis as Streptomyces parvulus. The crude ethanol extract showed an MIC of 0.97 μg/mL for MRSA and B. subtilis, while the ethyl acetate extract showed MIC of 3.9 μg/mL for S. aureus and MRSA, showing the greatest potential among the metabolites produced. Chemical prospecting revealed the presence of mono/sesquiterpenes, proanthocyanidin, triterpenes, and steroids in both crude extracts. This study evaluates S. parvulus activity against multi-resistant microorganisms such as MRSA. Thus, it proves that low-fertility soil, as is found in the Caatinga, may contain important microorganisms for the development of new antimicrobial drugs.

  6. Vegetation of the Hantam-Tanqua-Roggeveld subregion, South Africa Part 2: Succulent Karoo Biome related vegetation

    Directory of Open Access Journals (Sweden)

    Helga van der Merwe

    2009-03-01

    Full Text Available The Hantam-Tanqua-Roggeveld subregion lies within the Succulent Karoo Hotspot that stretches along the western side of the Republic of South Africa and Namibia. This project, carried out to document the botanical diversity in the Hantam-Tanqua-Roggeveld subregion, was part of a project identified as a priority during the SKEP (Succulent Karoo Ecosystem Programme initiative in this Hotspot. Botanical surveys were conducted in an area covering over three million hectares. Satellite images of the area and topocadastral, land type and geology maps were used to stratify the area into relatively homogeneous units. An analysis of the floristic data of 390 sample plots identified two major floristic units, i.e. the Fynbos Biome related vegetation and the Succulent Karoo Biome related vegetation. A description of the vegetation related to the Succulent Karoo Biome is presented in this article. Seven associations, 16 subassociations and several mosaic vegetation units, consisting of more than one vegetation unit, were identified and mapped. Various threats to the vegetation in the region were identified during the survey and are briefly discussed.

  7. Integrating Taxonomic, Functional and Phylogenetic Beta Diversities: Interactive Effects with the Biome and Land Use across Taxa.

    Science.gov (United States)

    Corbelli, Julian Martin; Zurita, Gustavo Andres; Filloy, Julieta; Galvis, Juan Pablo; Vespa, Natalia Isabel; Bellocq, Isabel

    2015-01-01

    The spatial distribution of species, functional traits and phylogenetic relationships at both the regional and local scales provide complementary approaches to study patterns of biodiversity and help to untangle the mechanisms driving community assembly. Few studies have simultaneously considered the taxonomic (TBD), functional (FBD) and phylogenetic (PBD) facets of beta diversity. Here we analyze the associations between TBD, FBD, and PBD with the biome (representing different regional species pools) and land use, and investigate whether TBD, FBD and PBD were correlated. In the study design we considered two widely used indicator taxa (birds and ants) from two contrasting biomes (subtropical forest and grassland) and land uses (tree plantations and cropfields) in the southern Neotropics. Non-metric multidimensional scaling showed that taxonomic, functional and phylogenetic distances were associated to biome and land use; study sites grouped into four groups on the bi-dimensional space (cropfields in forest and grassland, and tree plantations in forest and grassland), and that was consistent across beta diversity facets and taxa. Mantel and PERMANOVA tests showed that TBD, FBD and PBD were positively correlated for both bird and ant assemblages; in general, partial correlations were also significant. Some of the functional traits considered here were conserved along phylogeny. Our results will contribute to the development of sound land use planning and beta diversity conservation.

  8. Integrating Taxonomic, Functional and Phylogenetic Beta Diversities: Interactive Effects with the Biome and Land Use across Taxa

    Science.gov (United States)

    Corbelli, Julian Martin; Zurita, Gustavo Andres; Filloy, Julieta; Galvis, Juan Pablo; Vespa, Natalia Isabel; Bellocq, Isabel

    2015-01-01

    The spatial distribution of species, functional traits and phylogenetic relationships at both the regional and local scales provide complementary approaches to study patterns of biodiversity and help to untangle the mechanisms driving community assembly. Few studies have simultaneously considered the taxonomic (TBD), functional (FBD) and phylogenetic (PBD) facets of beta diversity. Here we analyze the associations between TBD, FBD, and PBD with the biome (representing different regional species pools) and land use, and investigate whether TBD, FBD and PBD were correlated. In the study design we considered two widely used indicator taxa (birds and ants) from two contrasting biomes (subtropical forest and grassland) and land uses (tree plantations and cropfields) in the southern Neotropics. Non-metric multidimensional scaling showed that taxonomic, functional and phylogenetic distances were associated to biome and land use; study sites grouped into four groups on the bi-dimensional space (cropfields in forest and grassland, and tree plantations in forest and grassland), and that was consistent across beta diversity facets and taxa. Mantel and PERMANOVA tests showed that TBD, FBD and PBD were positively correlated for both bird and ant assemblages; in general, partial correlations were also significant. Some of the functional traits considered here were conserved along phylogeny. Our results will contribute to the development of sound land use planning and beta diversity conservation. PMID:25978319

  9. Integrating Taxonomic, Functional and Phylogenetic Beta Diversities: Interactive Effects with the Biome and Land Use across Taxa.

    Directory of Open Access Journals (Sweden)

    Julian Martin Corbelli

    Full Text Available The spatial distribution of species, functional traits and phylogenetic relationships at both the regional and local scales provide complementary approaches to study patterns of biodiversity and help to untangle the mechanisms driving community assembly. Few studies have simultaneously considered the taxonomic (TBD, functional (FBD and phylogenetic (PBD facets of beta diversity. Here we analyze the associations between TBD, FBD, and PBD with the biome (representing different regional species pools and land use, and investigate whether TBD, FBD and PBD were correlated. In the study design we considered two widely used indicator taxa (birds and ants from two contrasting biomes (subtropical forest and grassland and land uses (tree plantations and cropfields in the southern Neotropics. Non-metric multidimensional scaling showed that taxonomic, functional and phylogenetic distances were associated to biome and land use; study sites grouped into four groups on the bi-dimensional space (cropfields in forest and grassland, and tree plantations in forest and grassland, and that was consistent across beta diversity facets and taxa. Mantel and PERMANOVA tests showed that TBD, FBD and PBD were positively correlated for both bird and ant assemblages; in general, partial correlations were also significant. Some of the functional traits considered here were conserved along phylogeny. Our results will contribute to the development of sound land use planning and beta diversity conservation.

  10. Modeling the Ecosystem Services Provided by Trees in Urban Ecosystems: Using Biome-BGC to Improve i-Tree Eco

    Science.gov (United States)

    Brown, Molly E.; McGroddy, Megan; Spence, Caitlin; Flake, Leah; Sarfraz, Amna; Nowak, David J.; Milesi, Cristina

    2012-01-01

    As the world becomes increasingly urban, the need to quantify the effect of trees in urban environments on energy usage, air pollution, local climate and nutrient run-off has increased. By identifying, quantifying and valuing the ecological activity that provides services in urban areas, stronger policies and improved quality of life for urban residents can be obtained. Here we focus on two radically different models that can be used to characterize urban forests. The i-Tree Eco model (formerly UFORE model) quantifies ecosystem services (e.g., air pollution removal, carbon storage) and values derived from urban trees based on field measurements of trees and local ancillary data sets. Biome-BGC (Biome BioGeoChemistry) is used to simulate the fluxes and storage of carbon, water, and nitrogen in natural environments. This paper compares i-Tree Eco's methods to those of Biome-BGC, which estimates the fluxes and storage of energy, carbon, water and nitrogen for vegetation and soil components of the ecosystem. We describe the two models and their differences in the way they calculate similar properties, with a focus on carbon and nitrogen. Finally, we discuss the implications of further integration of these two communities for land managers such as those in Maryland.

  11. Modeling distribution of Schinus molle L. in the Brazilian Pampa: insights on vegetation dynamics and conservation of the biome

    Directory of Open Access Journals (Sweden)

    R.P.M. Lemos

    2014-12-01

    Full Text Available Natural establishment of forests in the Brazilian Pampa biome should occur due to soil, hydrology and climate conditions, although no significant forest expansion over grassland has been noticed, precluded mainly by human interference and lack of environmental management. In this study, we used niche-modeling distribution of the tree species Schinus molle L. based on climatic variables to access the vegetation dynamics of the Brazilian Pampa and to develop strategies that assure the conservation of this biome, concerning both grassland and forest formations. Here we show that a large area of the Brazilian Pampa is suitable for expansion of S. molle populations, supporting the forest expansion over grassland as a natural process in this biome. We propose that the current absence of tree species expansion over the grassland in these areas is a result of the resilience of the grassland and of human interferences through expansion of agriculture, ranching and forestry with exotic species. Therefore, conservationist actions should focus on establishing preservation unities that include forest populations and grassland, while environmental management should be applied just in farming areas with historical human interference. Such actions will respect the ecological dynamics of the Pampa and value the forest formations in this grassland-dominated environment.

  12. Identification of novel mammalian hosts and Brazilian biome geographic distribution of Trypanosoma cruzi TcIII and TcIV.

    Science.gov (United States)

    Barros, Juliana Helena S; Xavier, Samanta Cristina C; Bilac, Daniele; Lima, Valdirene Santos; Dario, Maria Augusta; Jansen, Ana Maria

    2017-08-01

    Trypanosoma cruzi is a parasitic protozoan responsible for Chagas disease. Seven different Discrete Typing Units (DTUs) of T. cruzi are currently identified in nature: TcI-TcVI, and TcBat whose distribution patterns in nature, hosts/reservoirs and eco-epidemiological importance are still little known. Here, we present novel data on the geographic distribution and diversity of mammalian hosts and vectors of T. cruzi DTUs TcIII and TcIV. In this study, we analyzed 61 T. cruzi isolates obtained from 18 species of mammals (five orders) and two Hemiptera genera. Samples were collected from five Brazilian biomes (Pantanal, Caatinga, Cerrado, Atlantic Rainforest, and Amazon) previously characterized as Z3 or mixed infection (TcI-Z3) by mini-exon gene PCR. To identify TcIII and TcIV genotypes, we applied restriction fragment length polymorphism analysis to the PCR-amplified histone 3 gene. DTUs TcIII and TcIV were identified in single and mixed infections from wide dispersion throughout five Brazilian biomes studied, with TcIV being the most common. Pantanal was the biome that displayed the largest number of samples characterized as TcIII and TcIV in single and mixed infections, followed by Atlantic Rainforest and Amazon. Species from the Didelphimorphia order displayed the highest frequency of infection and were found in all five biomes. We report, for the first time, the infection of a species of the Artiodactyla order by DTU TcIII. In addition, we describe new host species: five mammals (marsupials and rodents) and two genera of Hemiptera. Our data indicate that DTUs TcIII and TcIV are more widespread and infect a larger number of mammalian species than previously thought. In addition, they are transmitted in restricted foci and cycles, but in different microhabitats and areas with distinct ecological profiles. Finally, we show that DTUs TcIII and TcIV do not present any specific association with biomes or host species. Copyright © 2017. Published by Elsevier B.V.

  13. Synergistic impacts of deforestation, climate change and fire on the future biomes distribution in Amazonia

    Science.gov (United States)

    Sampaio, G.; Cardoso, M. F.; Nobre, C. A.; Salazar, L. F.

    2013-05-01

    Several studies indicate future increase of environmental risks for the ecosystems in the Amazon region as a result of climate and land-use change, and their synergistic interactions. Modeling studies (e.g. Oyama and Nobre 2004, Salazar et al. 2007, Malhi et al. 2008) project rapid and irreversible replacement of forests by savannas with large-scale losses of biodiversity and livelihoods for people in the region. This process is referred to as the Amazon Dieback, where accelerated plant mortality due to environmental changes lead to forest collapse and savannas expansion after "tipping points" in climate and land surface changes are achieved. In this study we performed new analyses to quantify how deforestation, climate change and fire may combine to affect the distribution of major biomes in Amazonia. Changes in land use consider deforestation scenarios of 0%, 20%, 40%, and 50% (Sampaio et al., 2007), with and without fires (Cardoso et al., 2008), under the two greenhouse gases scenarios B1 and A2 and three "representative concentration pathways" (RCPs): 2.6, 4.5 and 8.5, for years 2015-2034 and 2040-2059 ("2025" and "2050" time-slices), from IPCC AR4 and CMIP5. The results show that the area affected in scenarios A2 and RCP 8.5 is larger than in the climate scenario B1 and RCP 2.6, and in both cases the effect is progressively higher in time. Most important changes occur in the East and South of the Amazon, with replacement of tropical forest by seasonal forest and savanna. The effect of fire in this region is important in all scenarios. The Northwest Amazon presents the smallest changes in the area of tropical forest, indicating that even for substantial land-use modifications and global climate change, the resulting atmospheric conditions would still support tropical forest in the region. In summary, we conclude that the synergistic combination of deforestation, climate change resulting from global warming, and the potential for higher fire occurrence may lead

  14. Legislación española sobre investigación biomédica en terapia celular: análisis bioético a través del método de Elio Sgreccia.

    OpenAIRE

    Del Castillo Díez, María

    2015-01-01

    El ser humano ha buscado siempre una solución contra el sufrimiento. A pesar de formar parte intrínseca de su vida, sigue sin aceptar el dolor, la enfermedad ni tampoco la muerte.En los últimos años la medicina y la biología se han unido en una lucha sin cuartel contra las enfermedades y la muerte, desarrollando una serie de técnicas e investigaciones (la clonación, las investigaciones biomédicas con células troncales o las terapias celulares y génicas) que han marcado un hito en el desarroll...

  15. Adsorption-desorption reactions of selenium (VI) in tropical cultivated and uncultivated soils under Cerrado biome.

    Science.gov (United States)

    Lessa, J H L; Araujo, A M; Silva, G N T; Guilherme, L R G; Lopes, G

    2016-12-01

    Soil management may affect selenium (Se) adsorption capacity. This study investigated adsorption and desorption of Se (VI) in selected Brazilian soils from the Cerrado biome, an area of ever increasing importance for agriculture expansion in Brazil. Soil samples were collected from cultivated and uncultivated soils, comprising clayed and sandy soils. Following chemical and mineralogical characterization, soil samples were subjected to Se adsorption and desorption tests. Adsorption was evaluated after a 72-h reaction with increasing concentrations of Se (0-2000 μg L -1 ) added as Na 2 SeO 4 in a NaCl electrolyte solution (pH 5.5; ionic strength 15 mmol L -1 ). Desorption, as well as distribution coefficients (K d ) for selenate were also assessed. Soil management affected Se adsorption capacity, i.e., Se adsorbed amounts were higher for uncultivated soils, when compared to cultivated ones. Such results were also supported by data of K d and maximum adsorption capacity of Se. This fact was attributed mainly to the presence of greater amounts of competing anions, especially phosphate, in cultivated soils, due to fertilizer application. Phosphate may compete with selenate for adsorption sites, decreasing Se retention. For the same group of soils (cultivated and uncultivated), Se adsorption was greater in the clayed soils compared to sandy ones. Our results support the idea that adding Se (VI) to the soil is a good strategy to increase Se levels in food crops (agronomic biofortification), especially when crops are grown in soils that have been cultivated over the time due to their low Se adsorption capacity (high Se availability). Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae

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    Mário Luís Pessôa Guedes

    2014-03-01

    Full Text Available Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae. Considering that some species of Culicidae are vectors of pathogens, both the knowledge of the diversity of the mosquito fauna and how some environment factors influence in it, are important subjects. In order to address the composition of Culicidae species in a forest reserve in southern Atlantic Forest, we compared biotic and abiotic environmental determinants and how they were associated with the occurrence of species between sunset and sunrise. The level of conservation of the area was also considered. The investigation was carried out at Reserva Natural do Morro da Mina, in Antonina, state of Paraná, Brazil. We performed sixteen mosquito collections employing Shannon traps at three-hour intervals, from July 2008 to June 2009. The characterization of the area was determined using ecological indices of diversity, evenness, dominance and similarity. We compared the frequency of specimens with abiotic variables, i.e., temperature, relative humidity and pluviosity. Seven thousand four hundred ten mosquito females were captured. They belong to 48 species of 12 genera. The most abundant genera were Anopheles, Culex, Coquillettidia, Aedes and Runchomyia. Among the species, the most abundant was Anopheles cruzii, the primary vector of Plasmodium spp. in the Atlantic Forest. Results of the analyses showed that the abiotic variables we tested did not influence the occurrence of species, although certain values suggested that there was an optimum range for the occurrence of culicid species. It was possible to detect the presence of species of Culicidae with different epidemiologic profiles and habitat preference.

  17. Implications of a lightning-rich tundra biome for permafrost carbon and vegetation dynamics

    Science.gov (United States)

    Chen, Y.; Veraverbeke, S.; Randerson, J. T.

    2017-12-01

    Lightning is a major ignition source of wildfires in circumpolar boreal forests but rarely occurs in arctic tundra. While theoretical and empirical work suggests that climate change will increase lightning strikes in temperate regions, much less is known about future changes in lightning across terrestrial ecosystems at high northern latitudes. Here we analyzed the spatial and temporal patterns of lightning flash rate (FR) from the satellite observations and surface detection networks. Regression models between the observed FR from the Optical Transient Detector on the MicroLab-1 satellite (later renamed OV-1) and meteorological parameters, including surface temperature (T), convective available potential energy (CAPE), and convective precipitation (CP) from ECMWF (European Centre for Medium-Range Weather Forecasts) ERA-interim reanalysis, were established and assessed. We found that FR had significant linear correlations with CAPE and CP, and a strong non-linear relationship with T. The statistical model based on T and CP can reproduce most of the spatial and temporal variability in FR in the circumpolar region. By using the regression model and meteorological predictions from 24 earth system models in the Coupled Model Intercomparison Project Phase 5 (CMIP5), we estimated the spatial distribution of FR by the end of the 21st century. Due to increases in surface temperature and convection, modeled FR shows substantial increase in northern biomes, including a 338% change in arctic tundra and a 185% change in regions with permafrost soil carbon reservoirs. These changes highlight a new mechanism by which permafrost carbon is vulnerable to the sustained impacts of climate warming. Increased fire in a warmer and lightning-rich future near the treeline has the potential to accelerate the northward migration of trees, which may further enhance warming and the abundance of lightning strikes.

  18. Regional Atmospheric CO2 Inversion Reveals Seasonal and Geographic Differences in Amazon Net Biome Exchange

    Science.gov (United States)

    Alden, Caroline B.; Miller, John B.; Gatti, Luciana V.; Gloor, Manuel M.; Guan, Kaiyu; Michalak, Anna M.; van der Laan-Luijkx, Ingrid; Touma, Danielle; Andrews, Arlyn; Basso, Luana G.; hide

    2016-01-01

    Understanding tropical rainforest carbon exchange and its response to heat and drought is critical for quantifying the effects of climate change on tropical ecosystems, including global climate carbon feedbacks. Of particular importance for the global carbon budget is net biome exchange of CO2 with the atmosphere (NBE), which represents nonfire carbon fluxes into and out of biomass and soils. Subannual and sub-Basin Amazon NBE estimates have relied heavily on process-based biosphere models, despite lack of model agreement with plot-scale observations. We present a new analysis of airborne measurements that reveals monthly, regional-scale (Approx.1-8 x 10(exp -6) km2) NBE variations. We develop a regional atmospheric CO2 inversion that provides the first analysis of geographic and temporal variability in Amazon biosphere-atmosphere carbon exchange and that is minimally influenced by biosphere model-based first guesses of seasonal and annual mean fluxes. We find little evidence for a clear seasonal cycle in Amazon NBE but do find NBE sensitivity to aberrations from long-term mean climate. In particular, we observe increased NBE (more carbon emitted to the atmosphere) associated with heat and drought in 2010, and correlations between wet season NBE and precipitation (negative correlation) and temperature (positive correlation). In the eastern Amazon, pulses of increased NBE persisted through 2011, suggesting legacy effects of 2010 heat and drought. We also identify regional differences in postdrought NBE that appear related to long-term water availability. We examine satellite proxies and find evidence for higher gross primary productivity (GPP) during a pulse of increased carbon uptake in 2011, and lower GPP during a period of increased NBE in the 2010 dry season drought, but links between GPP and NBE changes are not conclusive. These results provide novel evidence of NBE sensitivity to short-term temperature and moisture extremes in the Amazon, where monthly and sub

  19. Requisitos uniformes para preparar los manuscritos enviados a revistas biomédicas

    Directory of Open Access Journals (Sweden)

    1998-01-01

    Full Text Available En 1978, un reducido grupo de directores de revistas médicas generales que se publican en inglés se reunió de manera informal en Vancouver (Canadá a fin de fijar normas con respecto al formato que deberían adoptar los manuscritos enviados a esas publicaciones. Este fue el inicio de lo que con el tiempo llegó a conocerse como el Grupo de Vancouver. Sus requisitos para la preparación de manuscritos, que incluían el formato de las referencias bibliográficas creado por la Biblioteca Nacional de Medicina de los Estados Unidos, se publicaron por vez primera en 1979. Con el paso del tiempo el Grupo de Vancouver creció y se convirtió en el Comité Internacional de Directores de Revistas Médicas (CIDRM, que se reúne una vez al año y que gradualmente ha venido ampliando los temas que le conciernen. El Comité ha producido cinco ediciones de los requisitos uniformes para preparar los manuscritos enviados a revistas biomédicas. A lo largo de los años han surgido asuntos que van más allá de la preparación del manuscrito. Algunos de esos asuntos se han incorporado a los requisitos uniformes, mientras que otros se tratan en declaraciones por separado. Cada declaración se ha publicado en una revista científica.

  20. Net Biome Productivity of different land use at the sites of the Tharandt cluster

    Science.gov (United States)

    Grünwald, T.; Prescher, A.-K.; Bernhofer, Ch.

    2009-04-01

    Within the Tharandt cluster there are 5 flux monitoring sites including 3 CARBOEUROPE main sites. The CARBOEUROPE sites cover typical land use of the region (spruce [monitored since 1996], grassland [since 2003], cropland [since 2004]). For all sites estimates of the Net Biome Productivity (NBP) and its uncertainty have been derived using Net Ecosystem Productivity (NEP) based on the EC measurements and C exports and imports on an annual basis. The crop site is a small C sink (NEP of 30-110gCm-2a-1) only. The annual NEP values are dependent on the cultivated crop species (winter or summer crop). Including C export (harvest) and C import (manure spreading) lead to a considerable C source of 270-540gCm-2a-1. Organic fertilisation (C import) has a strong impact on NBP values expressed in a reduced annual net carbon source. Also, the largest interannual differences of NBP values are found at this site - mainly induced by the existence and the amount of a carbon import due to organic fertilisation. Management practices affect the NBP in a sensitive way at this crop site. Each crop shows a higher C export due to harvest than the annual NEP. To validate the calculated C equivalent using harvested grain biomass modelled NPP values are available. Uncertainty ranges of C export, C import and NBP as well as the grassland and spruce NBP (for comparison) are also stated. In general, land use and management strongly affect the annual NBP of non-forested ecosystems especially. So, this is the second main driver of the C budget besides the interannual variability in meteorological conditions and water availability with its influence on NEP, GPP and TER.

  1. Ecosystem-scale carbon monoxide exchange and partitioning across major biomes in Europe

    Science.gov (United States)

    Hammerle, Albin; Spielmann, Felix; Kitz, Florian; Ibrom, Andreas; Migliavacca, Mirco; Noe, Steffen; Kolle, Olaf; Moreno, Gerardo; Wohlfahrt, Georg

    2017-04-01

    With an average mole fraction of 100 ppb carbon monoxide (CO) plays a critical role in atmospheric chemistry and has an indirect global warming potential. While sources/sinks of CO on land at least partially cancel out each other and their magnitude is very likely lower compared to other sinks and sources, the magnitude of CO sources and sinks is highly uncertain. Thus it may be premature to neglect any direct contributions of land ecosystems to the CO budget. In addition, changes in global climate and resulting changes in global productivity may require re-evaluating older data and assumptions. One major reason for the large uncertainty is a general scarcity of empirical data. Here we present data on continuous eddy covariance measurements of CO-fluxes above different biomes in Europe in combination with soil-chamber flux measurements. Eddy covariance and soil-chamber measurements were conducted during the vegetation periods in 2015 and 2016 at a temperate grassland (AUT), a Mediterranean savanna (ESP), a temperate mixed deciduous (DEN) and a hemi-boreal forest (EST). While a clear diel pattern in ecosystem-scale CO-fluxes could be observed at the two grassland sites, with comparatively high emission rates at daytime conditions and fluxes around zero at night, no such pattern could be found for the two forest sites. Soil-chamber measurements mimicked the ecosystem-scale fluxes with CO-emissions during the day at the grassland ecosystems and slightly negative fluxes at night. Applying different treatments the influence of radiation and the availability of litter on these fluxes could be shown. Furthermore, a two-month rainout experiment revealed hardly any differences in CO soil fluxes between rainout- and control-plots at the grassland site (AUT), unless extremely dry conditions were reached.

  2. Assessing MODIS GPP in Non-Forested Biomes in Water Limited Areas Using EC Tower Data

    Directory of Open Access Journals (Sweden)

    Flor Álvarez-Taboada

    2015-03-01

    Full Text Available Although shrublands, savannas and grasslands account for 37% of the world’s terrestrial area, not many studies have analysed the role of these ecosystems in the global carbon cycle at a regional scale. The MODIS Gross Primary Production (GPP product is used here to help bridge this gap. In this study, the agreement between the MODIS GPP product (GPPm and the GPP Eddy Covariance tower data (GPPec was tested for six different sites in temperate and dry climatic regions (three grasslands, two shrublands and one evergreen forest. Results of this study show that for the non-forest sites in water-limited areas, GPPm is well correlated with GPPec at annual scales (r2 = 0.77, n = 12; SEE = 149.26 g C∙m−2∙year−1, although it tends to overestimate GPP and it is less accurate in the sites with permanent water restrictions. The use of biome-specific models based on precipitation measurements at a finer spatial resolution than the Data Assimilation Office (DAO values can increase the accuracy of these estimations. The seasonal dynamics and the beginning and end of the growing season were well captured by GPPm for the sites where (i the productivity was low throughout the year or (ii the changes in the flux trend were abrupt, usually due to the restrictions in water availability. The agreement between GPPec and GPPm in non-forested sites was lower on a weekly basis than at an annual scale (0.44 ≤ r2 ≤ 0.49, but these results were improved by including meteorological data at a finer spatial scale, and soil water content and temperature measurements in the model developed to predict GPPec (0.52 ≤ r2 ≤ 0.65.

  3. Quantitative comparison of the in situ microbial communities in different biomes

    Energy Technology Data Exchange (ETDEWEB)

    White, D.C. [Tennessee Univ., Knoxville, TN (United States)]|[Oak Ridge National Lab., TN (United States); Ringelberg, D.B.; Palmer, R.J. [Tennessee Univ., Knoxville, TN (United States). Center for Environmental Biotechnology

    1995-12-31

    A system to define microbial communities in different biomes requires the application of non-traditional methodology. Classical microbiological methods have severe limitations for the analysis of environmental samples. Pure-culture isolation, biochemical testing, and/or enumeration by direct microscopic counting are not well suited for the estimation of total biomass or the assessment of community composition within environmental samples. Such methods provide little insight into the in situ phenotypic activity of the extant microbiota since these techniques are dependent on microbial growth and thus select against many environmental microorganisms which are non- culturable under a wide range of conditions. It has been repeatedly documented in the literature that viable counts or direct counts of bacteria attached to sediment grains are difficult to quantitative and may grossly underestimate the extent of the existing community. The traditional tests provide little indication of the in situ nutritional status or for evidence of toxicity within the microbial community. A more recent development (MIDI Microbial Identification System), measure free and ester-linked fatty acids from isolated microorganisms. Bacterial isolates are identified by comparing their fatty acid profiles to the MIKI database which contains over 8000 entries. The application of the MIKI system to the analysis of environmental samples however, has significant drawbacks. The MIDI system was developed to identify clinical microorganisms and requires their isolation and culture on trypticase soy agar at 27{degrees}C. Since many isolates are unable to grow at these restrictive growth conditions, the system does not lend itself to identification of some environmental organisms. A more applicable methodology for environmental microbial analysis is based on the liquid extrication and separation of microbial lipids from environmental samples, followed by quantitative analysis using gas chromatography/

  4. Drivers of leaf carbon exchange capacity across biomes at the continental scale.

    Science.gov (United States)

    Smith, Nicholas G; Dukes, Jeffrey S

    2018-04-29

    Realistic representations of plant carbon exchange processes are necessary to reliably simulate biosphere-atmosphere feedbacks. These processes are known to vary over time and space, though the drivers of the underlying rates are still widely debated in the literature. Here, we measured leaf carbon exchange in >500 individuals of 98 species from the neotropics to high boreal biomes to determine the drivers of photosynthetic and dark respiration capacity. Covariate abiotic (long- and short-term climate) and biotic (plant type, plant size, ontogeny, water status) data were used to explore significant drivers of temperature-standardized leaf carbon exchange rates. Using model selection, we found the previous week's temperature and soil moisture at the time of measurement to be a better predictor of photosynthetic capacity than long-term climate, with the combination of high recent temperatures and low soil moisture tending to decrease photosynthetic capacity. Non-trees (annual and perennials) tended to have greater photosynthetic capacity than trees, and, within trees, adults tended to have greater photosynthetic capacity than juveniles, possibly as a result of differences in light availability. Dark respiration capacity was less responsive to the assessed drivers than photosynthetic capacity, with rates best predicted by multi-year average site temperature alone. Our results suggest that, across large spatial scales, photosynthetic capacity quickly adjusts to changing environmental conditions, namely light, temperature, and soil moisture. Respiratory capacity is more conservative and most responsive to longer-term conditions. Our results provide a framework for incorporating these processes into large-scale models and a dataset to benchmark such models. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. FLUXAPYROXAD IN THE ASIAN SOYBEAN RUST CONTROL IN THE CERRADO BIOME

    Directory of Open Access Journals (Sweden)

    RAFAEL MENEZES SILVA DE FREITAS

    2016-01-01

    Full Text Available The etiologic agent of the Asian soybean rust is the Phakopsora pachyrhizi, which causes a reduction in the photosynthetic leaf area and, consequently, in the crop yield. Chemical control is one of the main measures for its management. The objective of this work was to evaluate the efficacy and selectivity of the fluxapyroxad fungicide on controlling the Asian soybean rust, under the edaphoclimatic conditions of the Cerrado biome. The experiment was conducted in an area under no-tillage system, in the Agricultural Research Center, Rio Verde, Goias, Brazil, during the 2012/2013 crop season, using the cultivar NA7337. A randomized block experimental design was used, with twelve treatments and four replications. The treatments consisted of applications of fluxapyroxad (FX, pyraclostrobin (PT, epoxiconazole (EX and metconazole (MZ. The average severity of the disease in the plants reached 37% in the Control. All treatments with fungicides differed from the Control. Treatments 9, 10, 11 and 12 provided the greatest rates of soybean rust control. The treatments 10, 11 and 12 had the highest thousand grain weights, and the yields of the treatments 2, 3 and 11, despite higher than the Control, were lower than the treatments 4, 5, 6, 7, 8, 9, 10 and 12, which had statistically equal yields. The increasing in yield, compared to the Control, ranged from 10.05% (pyraclostrobin, epoxiconazole + pyraclostrobin + mineral oil to 30.55% (pyraclostrobin, pyraclostrobin + fluxapyroxad + mineral oil and pyraclostrobin + metconazole + mineral oil. The highest rates of soybean rust control were presented by fungicides containing fluxapyroxad.

  6. Examining the role of dissolved organic nitrogen in stream ecosystems across biomes and Critical Zone gradients

    Science.gov (United States)

    Wymore, A.; Rodriguez-Cardona, B.; Coble, A. A.; Potter, J.; Lopez Lloreda, C.; Perez Rivera, K.; De Jesus Roman, A.; Bernal, S.; Martí Roca, E.; Kram, P.; Hruska, J.; Prokishkin, A. S.; McDowell, W. H.

    2016-12-01

    Watershed nitrogen exports are often dominated by dissolved organic nitrogen (DON); yet, little is known about the role ambient DON plays in ecosystems. As an organic nutrient, DON may serve as either an energy source or as a nutrient source. One hypothesized control on DON is nitrate (NO3-) availability. Here we examine the interaction of NO3- and DON in streams across temperate forests, tropical rainforests, and Mediterranean and taiga biomes. Experimental streams also drain contrasting Critical Zones which provide gradients of vegetation, soil type and lithology (e.g. volcaniclastic, granitic, ultramafic, Siberian Traps Flood Basalt) in which to explore how the architecture of the Critical Zone affects microbial biogeochemical reactions. Streams ranged in background dissolved organic carbon (DOC) concentration (1-50 mg C/L) and DOC: NO3- ratios (10-2000). We performed a series of ecosystem-scale NO3- additions in multiple streams within each environment and measured the change in DON concentration. Results demonstrate that there is considerable temporal and spatial variation across systems with DON both increasing and decreasing in response to NO3- addition. Ecologically this suggests that DON can serve as both a nutrient source and an energy source to aquatic microbial communities. In contrast, DOC concentrations rarely changed in response to NO3- additions suggesting that the N-rich fraction of the ambient dissolved organic matter pool is more bioreactive than the C-rich fraction. Contrasting responses of the DON and DOC pools indicate different mechanisms controlling their respective cycling. It is likely that DON plays a larger role in ecosystems than previously recognized.

  7. The Use of Edge-Betweenness Clustering to Investigate Biological Function in Protein Interaction Networks

    OpenAIRE

    Dunn, Ruth; Dudbridge, Frank; Sanderson, Christopher M.

    2005-01-01

    RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are. Abstract Backgrou...

  8. Dominating biological networks.

    Directory of Open Access Journals (Sweden)

    Tijana Milenković

    Full Text Available Proteins are essential macromolecules of life that carry out most cellular processes. Since proteins aggregate to perform function, and since protein-protein interaction (PPI networks model these aggregations, one would expect to uncover new biology from PPI network topology. Hence, using PPI networks to predict protein function and role of protein pathways in disease has received attention. A debate remains open about whether network properties of "biologically central (BC" genes (i.e., their protein products, such as those involved in aging, cancer, infectious diseases, or signaling and drug-targeted pathways, exhibit some topological centrality compared to the rest of the proteins in the human PPI network.To help resolve this debate, we design new network-based approaches and apply them to get new insight into biological function and disease. We hypothesize that BC genes have a topologically central (TC role in the human PPI network. We propose two different concepts of topological centrality. We design a new centrality measure to capture complex wirings of proteins in the network that identifies as TC those proteins that reside in dense extended network neighborhoods. Also, we use the notion of domination and find dominating sets (DSs in the PPI network, i.e., sets of proteins such that every protein is either in the DS or is a neighbor of the DS. Clearly, a DS has a TC role, as it enables efficient communication between different network parts. We find statistically significant enrichment in BC genes of TC nodes and outperform the existing methods indicating that genes involved in key biological processes occupy topologically complex and dense regions of the network and correspond to its "spine" that connects all other network parts and can thus pass cellular signals efficiently throughout the network. To our knowledge, this is the first study that explores domination in the context of PPI networks.

  9. Modern Biology

    OpenAIRE

    ALEKSIC, Branko

    2014-01-01

    The purpose of this course is to learn the philosophy, principles, and techniques of modern biology. The course is particularly designed for those who have not learned biology previously or whose major is other than biology, and who may think that they do not need to know any biology at all. The topics are covered in a rather general, overview manner, but certain level of diligence in grasping concepts and memorizing the terminology is expected.

  10. Towards reconstructing herbaceous biome dynamics and associated precipitation in Africa: insights from the classification of grass morphological traits

    Science.gov (United States)

    Pasturel, Marine; Alexandre, Anne; Novello, Alice; Moctar Dieye, Amadou; Wele, Abdoulaye; Paradis, Laure; Hely, Christelle

    2014-05-01

    Inter-tropical herbaceous ecosystems occupy a 1/5th of terrestrial surface, a half of the African continent, and are expected to extend in the next decades. Dynamic of these ecosystems is simulated with poor accuracy by Dynamic Global Vegetation Models (DGVMs). One of the bias results from the fact that the diversity of the grass layer dominating these herbaceous ecosystems is poorly taken into account. Mean annual precipitation and the length of the dry season are the main constrains of the dynamics of these ecosystems. Conversely, changes in vegetation affect the water cycle. Inaccuracy in herbaceous ecosystem simulation thus impacts simulations of the water cycle (including precipitation) and vice versa. In order to increase our knowledge of the relationships between grass morphological traits, taxonomy, biomes and climatic niches in Western and South Africa, a 3-step methodology was followed: i) values of culm height, leaf length and width of dominant grass species from Senegal were gathered from flora and clustered using the Partition Around Medoids (PAM) method; ii) trait group ability to sign climatic domains and biomes was assessed using Kruskal-Wallis tests; iii) genericity and robustness of the trait groups were evaluated through their application to Chadian and South African botanical datasets. Results show that 8 grass trait groups are present either in Senegal, Chad or South Africa. These 8 trait groups are distributed along mean annual precipitation and dry season length gradients. The combination of three of them allow to discriminate mean annual precipitation domains (1000 mm) and herbaceous biomes (steppes, savannas, South African grasslands and Nama-Karoo). With these results in hand, grass Plant Functional Types (PFTs) of the DGMV LPJ-GUESS will be re-parameterized and particular attention will be given to the herbaceous biomass assigned to each grass trait group. Simultaneously, relationships between grass trait groups and phytolith vegetation

  11. The Intestinal Eukaryotic and Bacterial Biome of Spotted Hyenas: The Impact of Social Status and Age on Diversity and Composition.

    Science.gov (United States)

    Heitlinger, Emanuel; Ferreira, Susana C M; Thierer, Dagmar; Hofer, Heribert; East, Marion L

    2017-01-01

    In mammals, two factors likely to affect the diversity and composition of intestinal bacteria (bacterial microbiome) and eukaryotes (eukaryome) are social status and age. In species in which social status determines access to resources, socially dominant animals maintain better immune processes and health status than subordinates. As high species diversity is an index of ecosystem health, the intestinal biome of healthier, socially dominant animals should be more diverse than those of subordinates. Gradual colonization of the juvenile intestine after birth predicts lower intestinal biome diversity in juveniles than adults. We tested these predictions on the effect of: (1) age (juvenile/adult) and (2) social status (low/high) on bacterial microbiome and eukaryome diversity and composition in the spotted hyena ( Crocuta crocuta ), a highly social, female-dominated carnivore in which social status determines access to resources. We comprehensively screened feces from 35 individually known adult females and 7 juveniles in the Serengeti ecosystem for bacteria and eukaryotes, using a set of 48 different amplicons (4 for bacterial 16S, 44 for eukaryote 18S) in a multi-amplicon sequencing approach. We compared sequence abundances to classical coprological egg or oocyst counts. For all parasite taxa detected in more than six samples, the number of sequence reads significantly predicted the number of eggs or oocysts counted, underscoring the value of an amplicon sequencing approach for quantitative measurements of parasite load. In line with our predictions, our results revealed a significantly less diverse microbiome in juveniles than adults and a significantly higher diversity of eukaryotes in high-ranking than low-ranking animals. We propose that free-ranging wildlife can provide an intriguing model system to assess the adaptive value of intestinal biome diversity for both bacteria and eukaryotes.

  12. Aplicaciones del SiC biomórfico como reforzante estructural en hormigones refractarios

    Directory of Open Access Journals (Sweden)

    Sepúlveda, R.

    2005-10-01

    Full Text Available This work is devoted to the study of the time and temperature dependence of the static grain growth in YTZP 4 mol %, with an average grain size within the submicrometric range (> 0.1 μm. Also, the mechanical response in the temperature interval between 1200 ºC and 1500 ºC is analysed. The grain growth is controlled by the yttria segregation at the grain boundaries, which plays a key role in the cationic diffusion processes. Microstructural characterization of both as-received and deformed samples allows to conclude that plastic deformation is due to grain boundary sliding (GBS, with stress exponents increasing with the flow stress, but in all cases they are lower than n = 2.

    Una posible aplicación del SiC biomórfico (bioSiC son los reforzante estructural en hormigones refractarios. En este caso se han fabricado piezas de bioSiC con forma de cilindros alargados, 3-4 mm de diámetro y 30-35 mm de longitud, mediante infiltración reactiva de Si líquido en piezas de carbón obtenidas por pirolización de madera de haya de calidad comercial. Hemos estudiado las características microestructurales y las propiedades mecánicas de los reforzantes, como paso previo al estudio de la aplicación mencionada, de la que se ofrece un avance en este trabajo. Para caracterizar la calidad del material y del proceso de fabricación, la microestructura de las piezas se ha estudiado mediante microscopía electrónica de barrido. Los reforzantes de bioSiC fueron ensayados a compresión uniaxial y flexión en cuatro puntos a temperatura ambiente y a alta temperatura (1250-1400ºC para la determinación de sus propiedades mecánicas, y se realizaron estudios fractográficos en el segundo tipo de ensayos. Subsecuentemente, se prepararon ladrillos refractarios con un 3% en peso de reforzantes de bioSiC, que fueron curados a diferentes temperaturas (máx. 1600ºC. Estos ladrillos se han ensayado en compresión y flexión en tres puntos, a temperatura ambiente

  13. A cross-biome synthesis of soil respiration and its determinants under simulated precipitation changes.

    Science.gov (United States)

    Liu, Lingli; Wang, Xin; Lajeunesse, Marc J; Miao, Guofang; Piao, Shilong; Wan, Shiqiang; Wu, Yuxin; Wang, Zhenhua; Yang, Sen; Li, Ping; Deng, Meifeng

    2016-04-01

    Soil respiration (Rs) is the second-largest terrestrial carbon (C) flux. Although Rs has been extensively studied across a broad range of biomes, there is surprisingly little consensus on how the spatiotemporal patterns of Rs will be altered in a warming climate with changing precipitation regimes. Here, we present a global synthesis Rs data from studies that have manipulated precipitation in the field by collating studies from 113 increased precipitation treatments, 91 decreased precipitation treatments, and 14 prolonged drought treatments. Our meta-analysis indicated that when the increased precipitation treatments were normalized to 28% above the ambient level, the soil moisture, Rs, and the temperature sensitivity (Q10) values increased by an average of 17%, 16%, and 6%, respectively, and the soil temperature decreased by -1.3%. The greatest increases in Rs and Q10 were observed in arid areas, and the stimulation rates decreased with increases in climate humidity. When the decreased precipitation treatments were normalized to 28% below the ambient level, the soil moisture and Rs values decreased by an average of -14% and -17%, respectively, and the soil temperature and Q10 values were not altered. The reductions in soil moisture tended to be greater in more humid areas. Prolonged drought without alterations in the amount of precipitation reduced the soil moisture and Rs by -12% and -6%, respectively, but did not alter Q10. Overall, our synthesis suggests that soil moisture and Rs tend to be more sensitive to increased precipitation in more arid areas and more responsive to decreased precipitation in more humid areas. The responses of Rs and Q10 were predominantly driven by precipitation-induced changes in the soil moisture, whereas changes in the soil temperature had limited impacts. Finally, our synthesis of prolonged drought experiments also emphasizes the importance of the timing and frequency of precipitation events on ecosystem C cycles. Given these

  14. Gully erosion in the Caatinga biome, Brazil: measurement and stochastic modelling

    Science.gov (United States)

    Lima Alencar, Pedro Henrique; de Araújo, José Carlos; Nonato Távora Costa, Raimundo

    2017-04-01

    In contrast with inter-rill erosion, which takes a long time to modify the terrain form, gully erosion can fast and severely change the landscape. In the Brazilian semiarid region, a one-million km2 area that coincides with the Caatinga biome, inter-rill erosion prevails due to the silty shallow soils. However, gully erosion does occur in the Caatinga, with temporal increasing severity. This source of sediment impacts the existing dense network of small dams, generating significant deleterious effects, such as water availability reduction in a drought-prone region. This study focuses on the Madalena basin (124 km2, state of Ceará, Brazil), a land-reform settlement with 20 inhabitants per km2, whose main economic activities are agriculture (especially Zea mays), livestock and fishing. In the catchment area, where there are 12 dams (with storage capacity ranging from 6.104 to 2.107 m3), gully erosion has become an issue due to its increasing occurrence. Eight gully-erosion sites have been identified in the basin, but most of them have not yet reached great dimensions (depth and/or width), nor interacted with groundwater, being therefore classified as ephemeral gullies. We selected the three most relevant sites and measured the topography of the eroded channels, as well as the neighboring terrain relief, using accurate total stations and unmanned aerial vehicle. The data was processed with the help of software, such as DataGeosis (Office 7.5) and Surfer (11.0), providing information on gully erosion in terms of (μ ± σ): projection area (317±165 m2), eroded mass (61±36 Mg) and volume (42±25 m3), length (38±6 m), maximum depth (0.58±0.13 m) and maximum width (6.00±2.35 m). The measured data are then compared with those provided by the Foster and Lane model (1986). The model generated results with considerable scatter. This is possibly due to uncertainties in the field parameters, which are neglected in the deterministic approach of most physically-based models

  15. Holocene evolution of lakes in the forest-tundra biome of northern Manitoba, Canada

    Science.gov (United States)

    Hobbs, William O.; Edlund, Mark B.; Umbanhowar, Charles E.; Camill, Philip; Lynch, Jason A.; Geiss, Christoph; Stefanova, Vania

    2017-03-01

    The late-Quaternary paleoenvironmental history of the western Hudson Bay region of Subarctic Canada is poorly constrained. Here, we present a regional overview of the post-glacial history of eight lakes which span the forest-tundra biome in northern Manitoba. We show that during the penultimate drainage phase of Lake Agassiz the lake water had an estimated pH of ∼6.0, with abundant quillwort (Isöetes spp.) along the lakeshore and littoral zone and some floating green algae (Botryococcus spp. and Pediastrum sp.). Based on multiple sediment proxies, modern lake ontogeny in the region commenced at ∼7500 cal yrs BP. Pioneering diatom communities were shaped by the turbid, higher alkalinity lake waters which were influenced by base cation weathering of the surrounding till following Lake Agassiz drainage. By ∼7000 cal yrs BP, soil development and Picea spp. establish and the lakes began a slow trajectory of acidification over the remaining Holocene epoch. The natural acidification of the lakes in this region is slow, on the order of several millennia for one pH unit. Each of the study lakes exhibit relatively stable aquatic communities during the Holocene Thermal Maximum, suggesting this period is a poor analogue for modern climatic changes. During the Neoglacial, the beginning of the post-Little Ice Age period represents the most significant climatic event to impact the lakes of N. Manitoba. In the context of regional lake histories, the rate of diatom floristic change in the last 200-300 years is unprecedented, with the exception of post-glacial lake ontogeny in some of the lakes. For nearly the entire history of the lakes in this region, there is a strong linkage between landscape development and the aquatic ecosystems; however this relationship appears to become decoupled or less strong in the post-LIA period. Significant 20th century changes in the aquatic ecosystem cannot be explained wholly by changes in the terrestrial ecosystem, suggesting that future

  16. Central Chile

    Science.gov (United States)

    2002-01-01

    The beginning of spring in central Chile looked like this to SeaWiFS. The snow-covered Andes mark the country's eastern border, and phytoplankton blooms and river sediment plumes fill the waters off its west coast. A large eddy due west of Concepcion is highlighted by the phytoplankton it contains.

  17. Afrique Centrale

    African Journals Online (AJOL)

    PR BOKO

    (Afrique Centrale) : peuplement de protozoaires ciliés et macro invertébrés ... Le lac d'Obili est un écosystème aquatique situé en plein cœur de Yaoundé en ...... électrique des eaux est assez stable, autour de 200 ; ce qui suppose que la ...

  18. Calibration of a biome-biogeochemical cycles model for modeling the net primary production of teak forests through inverse modeling of remotely sensed data

    Science.gov (United States)

    Imvitthaya, Chomchid; Honda, Kiyoshi; Lertlum, Surat; Tangtham, Nipon

    2011-01-01

    In this paper, we present the results of a net primary production (NPP) modeling of teak (Tectona grandis Lin F.), an important species in tropical deciduous forests. The biome-biogeochemical cycles or Biome-BGC model was calibrated to estimate net NPP through the inverse modeling approach. A genetic algorithm (GA) was linked with Biome-BGC to determine the optimal ecophysiological model parameters. The Biome-BGC was calibrated by adjusting the ecophysiological model parameters to fit the simulated LAI to the satellite LAI (SPOT-Vegetation), and the best fitness confirmed the high accuracy of generated ecophysioligical parameter from GA. The modeled NPP, using optimized parameters from GA as input data, was evaluated using daily NPP derived by the MODIS satellite and the annual field data in northern Thailand. The results showed that NPP obtained using the optimized ecophysiological parameters were more accurate than those obtained using default literature parameterization. This improvement occurred mainly because the model's optimized parameters reduced the bias by reducing systematic underestimation in the model. These Biome-BGC results can be effectively applied in teak forests in tropical areas. The study proposes a more effective method of using GA to determine ecophysiological parameters at the site level and represents a first step toward the analysis of the carbon budget of teak plantations at the regional scale.

  19. 改进Biome-BGC模型模拟哈佛森林地区水、碳通量%Simulation of water and carbon fluxes in Harvard forest area by using improved BiomeBGC model.

    Institute of Scientific and Technical Information of China (English)

    张廷龙; 孙睿; 胡波; 冯丽超; 张荣华

    2011-01-01

    Biome-BGC模型通过耦合植被、土壤与大气间的水分与CO2交换过程,实现植被生产力的模拟,但土壤水平衡模块的不够完善,导致在长时间无降水情况下植被生产力模拟存在较大误差.针对这一问题,本文对Biome-BGC模型中土壤水分胁迫气孔导度方程、蒸散计算公式及土壤水分流失过程等3方面进行了改进和调整,利用改进的Biome-BGC模型模拟美国哈佛森林地区蒸散、植被生产力,并与地面通量观测值进行了比较.结果表明,改进后模拟精度有明显的提高,蒸散、植被生态系统生产力(NEE)与观测值间的决定系数分别由0.483和0.658提高到0.617和O.813,蒸散逐年均方根误差平均下降了48.7%,NEE逐年误差平方和平均下降了39.8%.改进后的模型模拟结果更接近观测值.%Using Biome-BGC model can simulate vegetation productivity through the coupling of water and CO2 exchange processes between vegetation, soil and atmosphere, but the soil water balance module is not perfect enough, leading to a large deviation between simulated and observed values under condition of a long time no precipitation. Aiming at this problem, this paper improved and adjusted the equation of stomatal conductance stressed by soil water, the calculation formula of evapotranspiration, and the process of soil water loss in Biome-BGC model. Using this improved model, the evapotranspiration and vegetation productivity in Harvard Forest area were simulated, and compared with field observations. The accuracy of simulated results by the improved model enhanced obviously, with the evapotranspiration R between simulated and observed values increased from 0. 483 to 0. 617, NEE R2 increased from 0. 658 to 0. 813, root mean square error (RMSE) of annual evapotranspiration decreased averagely by 48. 7% , and annual sum squared error ( ASSE) of NEE decreased averagely by 39. 8% , which suggested that the simulated results by using the improved model

  20. Diversidad y aspectos biológicos de abejas silvestres de un ambiente urbano y otro natural de la región central de Santa Fe, Argentina Diversity and biological aspects of wild bees in an urban and a natural environment in the central region of Santa Fe, Argentina

    Directory of Open Access Journals (Sweden)

    Milagros Dalmazzo

    2010-06-01

    Full Text Available El objetivo del presente trabajo fue relevar el elenco de abejas silvestres en la región central de Santa Fe y comparar la diversidad de especies y aspectos biológicos en dos ambientes de una misma región. Las abejas fueron colectadas en el estrato herbáceo de la Reserva Universitaria "Escuela Granja" de la localidad Esperanza, y en la zona urbana de la localidad Susana, ambas ubicadas dentro de la Provincia Fitogeográfica del Espinal. La colecta se realizó en octubre, noviembre y diciembre de 2004 y en enero, febrero y marzo de 2005, registrando las especies vegetales sobre las que se capturaron. Se colectaron 277 ejemplares en total, de los cuales se identificaron 62 especies (27 géneros en 5 familias. Las curvas de rarefacción indican una tasa de acumulación de especies mayor para la Reserva Ecológica, los índices de diversidad de Shannon son 3,25 para la Reserva Ecológica y 2,64 para la Zona Urbana. Para la comparación de las comunidades en ambos sitios, las abejas fueron clasificadas en tres categorías según la especialización en el uso del recurso floral, sustrato de nidificación y comportamiento social. Se observó una asociación entre los grupos especialistas y de nidificación en el suelo con el ambiente natural, y por otro lado, las especies generalistas y de nidificación en cavidades con el ambiente urbano. No se identificaron diferencias, en cuanto a la sociabilidad de las especies, entre ambos sitios.The purpose of this contribution is to present a survey of wild bees in the central region of Santa Fe, and to compare the diversity and biological aspects of the bee communities at two different environments of the same region. Bees were surveyed at the ecological reserve Reserva Universitaria "Escuela Granja" in the locality of Esperanza, and at an urban area in the locality of Susana, both in the Espinal Phytogeographic Province. Bees were sampled from October to December 2004 and from January to March 2005

  1. Europa central

    Directory of Open Access Journals (Sweden)

    Karel BARTOSEK

    2010-02-01

    Full Text Available La investigación francesa continúa interesándose por Europa Central. Desde luego, hay límites a este interés en el ambiente general de mi nueva patria: en la ignorancia, producto del largo desinterés de Francia por este espacio después de la Segunda Guerra Mundial, y en el comportamiento y la reflexión de la clase política y de los medios de comunicación (una anécdota para ilustrar este ambiente: durante la preparación de nuestro coloquio «Refugiados e inmigrantes de Europa Central en el movimiento antifascista y la Resistencia en Francia, 1933-1945», celebrado en París en octubre de 1986, el problema de la definición fue planteado concreta y «prácticamente». ¡Y hubo entonces un historiador eminente, para quién Alemania no formaría parte de Europa Central!.

  2. Uso da rugoscopia palatina como ferramenta biométrica: um estudo populacional em Niterói-RJ, Brasil

    Directory of Open Access Journals (Sweden)

    Igor Iuco CASTRO-SILVA

    Full Text Available Introdução: Pesquisas por métodos biométricos auxiliares em perícias têm crescido na Odontologia Legal. Objetivo: Este estudo avaliou a eficácia da rugoscopia palatina na identificação humana. Material e método: Foram utilizados 184 modelos de gesso de estudantes voluntários em Niterói-RJ, para delineamento de suas rugosidades palatinas, sendo classificadas segundo quantidade, direção (sistema de Carrea e formato individual (sistema de Silva, e comparadas às variáveis demográficas sexo, cor da pele e idade. A análise estatística foi realizada com o teste qui-quadrado para amostras independentes, considerando-se p<0,05. Resultado: Houve maior prevalência de 2-7 rugas em homens. O tipo IV de Carrea e o tipo 1 de Silva foram mais evidentes, porém sem diferenças intergrupos significativas, de acordo com as variáveis propostas. Conclusão: A rugoscopia palatina é uma ferramenta biométrica viável e fornece informações morfológicas individuais relevantes, embora sua análise cega e em tempo único não exiba acurácia na estratificação populacional.

  3. The biogeographic origin of a radiation of trees in Madagascar: implications for the assembly of a tropical forest biome.

    Science.gov (United States)

    Federman, Sarah; Dornburg, Alex; Downie, Alexander; Richard, Alison F; Daly, Douglas C; Donoghue, Michael J

    2015-10-05

    Madagascar's rain forests are characterized by extreme and uneven patterns of species richness and endemicity, the biogeographic and evolutionary origins of which are poorly understood. Here we use a time-calibrated phylogeny of a dominant group of trees in Madagascar's eastern rain forests, Canarium, and related Burseraceae (Canarieae), to test biogeographic hypotheses regarding the origin and radiation of the flora of this unique biome. Our findings strongly support the monophyly of Malagasy Canarium, suggesting that this clade represents a previously undocumented in situ radiation. Contrary to expectations of dispersal from Africa during the Oligocene, concurrent with the formation of Madagascar's rain forest biome, our analyses support a late Miocene origin for Malagasy Canarium, probably by long distance dispersal from Southeast Asia. Our study illustrates the importance of considering long distance dispersal as a viable explanation for clades with pantropical distributions diversifying subsequent to the Oligocene, and it highlights the formation of the Indo-Australian Archipelago and associated fast-moving equatorial surface currents, suggesting an under-appreciated evolutionary link among tropical centers of endemism. We postulate that the relatively recent establishment and radiation of Canarium in Madagascar may have been facilitated by the highly stochastic climates associated with these forest ecosystems.

  4. Land-use change and soil type are drivers of fungal and archaeal communities in the Pampa biome.

    Science.gov (United States)

    Lupatini, Manoeli; Jacques, Rodrigo Josemar Seminoti; Antoniolli, Zaida Inês; Suleiman, Afnan Khalil Ahmad; Fulthorpe, Roberta R; Roesch, Luiz Fernando Würdig

    2013-02-01

    The current study aimed to test the hypothesis that both land-use change and soil type are responsible for the major changes in the fungal and archaeal community structure and functioning of the soil microbial community in Brazilian Pampa biome. Soil samples were collected at sites with different land-uses (native grassland, native forest, Eucalyptus and Acacia plantation, soybean and watermelon field) and in a typical toposequence in Pampa biome formed by Paleudult, Albaqualf and alluvial soils. The structure of soil microbial community (archaeal and fungal) was evaluated by ribosomal intergenic spacer analysis and soil functional capabilities were measured by microbial biomass carbon and metabolic quotient. We detected different patterns in microbial community driven by land-use change and soil type, showing that both factors are significant drivers of fungal and archaeal community structure and biomass and microbial activity. Fungal community structure was more affected by land-use and archaeal community was more affected by soil type. Irrespective of the land-use or soil type, a large percentage of operational taxonomic unit were shared among the soils. We accepted the hypothesis that both land-use change and soil type are drivers of archaeal and fungal community structure and soil functional capabilities. Moreover, we also suggest the existence of a soil microbial core.

  5. Hydrology of a Water‐Limited Forest under Climate Change Scenarios: The Case of the Caatinga Biome, Brazil

    Directory of Open Access Journals (Sweden)

    Everton Alves Rodrigues Pinheiro

    2017-02-01

    Full Text Available Given the strong interactions between climate and vegetation, climate change effects on natural and agricultural ecosystems are common objects of research. Reduced water availability is predicted to take place across large regions of the globe, including Northeastern Brazil. The Caatinga, a complex tropical water‐limited ecosystem and the only exclusively Brazilian biome, prevails as the main natural forest of this region. The aim of this study was to examine the soil‐water balance for this biome under a climate‐warming scenario and with reduced rainfall. Climate change projections were assessed from regional circulation models earlier applied to the Brazilian territory. A statistical climate data generator was used to compose a synthetic weather dataset, which was later integrated into a hydrological model. Compared to simulations with current climate for the same site, under the scenario with climate change, transpiration was enhanced by 36%, and soilwater evaporation and interception were reduced by 16% and 34%, respectively. The greatest change in soil‐water components was observed for deep drainage, accounting only for 2% of the annual rainfall. Soil‐plant‐atmosphere fluxes seem to be controlled by the top layer (0.0-0.2 m, which provides 80% of the total transpiration, suggesting that the Caatinga forest may become completely soil‐water pulse dominated under scenarios of reduced water availability.

  6. Ética e pesquisa biomédica em sociedades indígenas no Brasil

    Directory of Open Access Journals (Sweden)

    Coimbra Jr. Carlos E. A.

    1996-01-01

    Full Text Available Este trabalho discute questões relativas à ética da investigação biomédica em populações indígenas brasileiras, em particular no que tange à obtenção de consentimento pós-informacional em pesquisas que envolvam a coleta de amostras biológicas. Enfatiza-se que nada há de específico na legislação atual com respeito à pesquisa biomédica nestas populações. A partir de uma perspectiva antropológica, os autores analisam algumas das dificuldades para a obtenção do consentimento "realmente" informado. Chama-se atenção para a importância das discussões sobre ética em pesquisa face a possibilidade de utilização comercial de amostras biológicas, como exemplificado pelo atual debate sobre patenteamento de material genético humano.

  7. Small molecules: the missing link in the central dogma.

    Science.gov (United States)

    Schreiber, Stuart L

    2005-07-01

    Small molecules have critical roles at all levels of biological complexity and yet remain orphans of the central dogma. Chemical biologists, working with small molecules, expand our understanding of these central elements of life.

  8. Stormflow influence on nutrient dynamics in micro-catchments under contrasting land use in the Cerrado and Amazon Biomes, Brazil

    Science.gov (United States)

    Edelmann, Katharina; Nóbrega, Rodolfo L. B.; Gerold, Gerhard

    2017-04-01

    The Amazon and Cerrado biomes in Brazil have been under intense land-use change during the past few decades. The conversion of native vegetation to pastures and croplands has caused impacts on hydrological processes in these biomes, resulting in increased streamflow and nutrient fluxes. Our aim was to compare the nutrient dynamics during stormflow events in two pairs of adjacent micro-catchments with similar physical characteristics under contrasting land use, i.e. native vegetation (rainforest or cerrado) and pasture. One pair of catchments was located in the Amazon and the other in the Cerrado, both on the Amazon Agricultural Frontier in the Brazilian states of Mato Grosso and Pará. We collected hydrological and hydrochemical data on 50 stormflow events on a sub-hourly resolution during the wet seasons of 2013 and 2014. We compared the dynamics of total inorganic carbon (TIC), total organic carbon (TOC), dissolved organic carbon (DOC), nitrate (NO3), calcium (Ca), potassium (K), and magnesium (Mg) in different hydrograph parts, i.e. rising limb, peak and recession limb, between the catchments within the same biome. For the Cerrado biome, our findings show that the nutrient concentrations in the stormflows were higher in the pasture catchment than in the cerrado catchment. In the Amazon biome, we found an inverse relationship with higher concentrations in the forest catchment than in the pasture catchment, except for TIC and K. Most nutrients in the cerrado catchment had the highest concentrations in the rising limb. Mg, however, reached highest concentrations during peak discharge, and lowest in the recession limb. In the adjacent pasture catchment, in contrast, the highest nutrient concentrations were observed during the peak discharge (TIC, TOC, Ca) or the recession limb (DOC, NO3, K, Mg) with lowest in the rising limb, except for NO3, which showed the lowest concentrations during peak discharge. In the Amazon forest catchment, the peak discharge showed the

  9. Francis Crick, DNA, and the Central Dogma

    Science.gov (United States)

    Olby, Robert

    1970-01-01

    This essay describes how Francis Crick, ex-physicist, entered the field of biology and discovered the structure of DNA. Emphasis is upon the double helix, the sequence hypothesis, the central dogma, and the genetic code. (VW)

  10. Are There Consistent Grazing Indicators in Drylands? Testing Plant Functional Types of Various Complexity in South Africa’s Grassland and Savanna Biomes

    Science.gov (United States)

    Linstädter, Anja; Schellberg, Jürgen; Brüser, Katharina; Moreno García, Cristian A.; Oomen, Roelof J.; du Preez, Chris C.; Ruppert, Jan C.; Ewert, Frank

    2014-01-01

    Despite our growing knowledge on plants’ functional responses to grazing, there is no consensus if an optimum level of functional aggregation exists for detecting grazing effects in drylands. With a comparative approach we searched for plant functional types (PFTs) with a consistent response to grazing across two areas differing in climatic aridity, situated in South Africa’s grassland and savanna biomes. We aggregated herbaceous species into PFTs, using hierarchical combinations of traits (from single- to three-trait PFTs). Traits relate to life history, growth form and leaf width. We first confirmed that soil and grazing gradients were largely independent from each other, and then searched in each biome for PFTs with a sensitive response to grazing, avoiding confounding with soil conditions. We found no response consistency, but biome-specific optimum aggregation levels. Three-trait PFTs (e.g. broad-leaved perennial grasses) and two-trait PFTs (e.g. perennial grasses) performed best as indicators of grazing effects in the semi-arid grassland and in the arid savanna biome, respectively. Some PFTs increased with grazing pressure in the grassland, but decreased in the savanna. We applied biome-specific grazing indicators to evaluate if differences in grazing management related to land tenure (communal versus freehold) had effects on vegetation. Tenure effects were small, which we mainly attributed to large variability in grazing pressure across farms. We conclude that the striking lack of generalizable PFT responses to grazing is due to a convergence of aridity and grazing effects, and unlikely to be overcome by more refined classification approaches. Hence, PFTs with an opposite response to grazing in the two biomes rather have a unimodal response along a gradient of additive forces of aridity and grazing. The study advocates for hierarchical trait combinations to identify localized indicator sets for grazing effects. Its methodological approach may also be

  11. Are there consistent grazing indicators in Drylands? Testing plant functional types of various complexity in South Africa's Grassland and Savanna Biomes.

    Directory of Open Access Journals (Sweden)

    Anja Linstädter

    Full Text Available Despite our growing knowledge on plants' functional responses to grazing, there is no consensus if an optimum level of functional aggregation exists for detecting grazing effects in drylands. With a comparative approach we searched for plant functional types (PFTs with a consistent response to grazing across two areas differing in climatic aridity, situated in South Africa's grassland and savanna biomes. We aggregated herbaceous species into PFTs, using hierarchical combinations of traits (from single- to three-trait PFTs. Traits relate to life history, growth form and leaf width. We first confirmed that soil and grazing gradients were largely independent from each other, and then searched in each biome for PFTs with a sensitive response to grazing, avoiding confounding with soil conditions. We found no response consistency, but biome-specific optimum aggregation levels. Three-trait PFTs (e.g. broad-leaved perennial grasses and two-trait PFTs (e.g. perennial grasses performed best as indicators of grazing effects in the semi-arid grassland and in the arid savanna biome, respectively. Some PFTs increased with grazing pressure in the grassland, but decreased in the savanna. We applied biome-specific grazing indicators to evaluate if differences in grazing management related to land tenure (communal versus freehold had effects on vegetation. Tenure effects were small, which we mainly attributed to large variability in grazing pressure across farms. We conclude that the striking lack of generalizable PFT responses to grazing is due to a convergence of aridity and grazing effects, and unlikely to be overcome by more refined classification approaches. Hence, PFTs with an opposite response to grazing in the two biomes rather have a unimodal response along a gradient of additive forces of aridity and grazing. The study advocates for hierarchical trait combinations to identify localized indicator sets for grazing effects. Its methodological approach may

  12. Are there consistent grazing indicators in Drylands? Testing plant functional types of various complexity in South Africa's Grassland and Savanna Biomes.

    Science.gov (United States)

    Linstädter, Anja; Schellberg, Jürgen; Brüser, Katharina; Moreno García, Cristian A; Oomen, Roelof J; du Preez, Chris C; Ruppert, Jan C; Ewert, Frank

    2014-01-01

    Despite our growing knowledge on plants' functional responses to grazing, there is no consensus if an optimum level of functional aggregation exists for detecting grazing effects in drylands. With a comparative approach we searched for plant functional types (PFTs) with a consistent response to grazing across two areas differing in climatic aridity, situated in South Africa's grassland and savanna biomes. We aggregated herbaceous species into PFTs, using hierarchical combinations of traits (from single- to three-trait PFTs). Traits relate to life history, growth form and leaf width. We first confirmed that soil and grazing gradients were largely independent from each other, and then searched in each biome for PFTs with a sensitive response to grazing, avoiding confounding with soil conditions. We found no response consistency, but biome-specific optimum aggregation levels. Three-trait PFTs (e.g. broad-leaved perennial grasses) and two-trait PFTs (e.g. perennial grasses) performed best as indicators of grazing effects in the semi-arid grassland and in the arid savanna biome, respectively. Some PFTs increased with grazing pressure in the grassland, but decreased in the savanna. We applied biome-specific grazing indicators to evaluate if differences in grazing management related to land tenure (communal versus freehold) had effects on vegetation. Tenure effects were small, which we mainly attributed to large variability in grazing pressure across farms. We conclude that the striking lack of generalizable PFT responses to grazing is due to a convergence of aridity and grazing effects, and unlikely to be overcome by more refined classification approaches. Hence, PFTs with an opposite response to grazing in the two biomes rather have a unimodal response along a gradient of additive forces of aridity and grazing. The study advocates for hierarchical trait combinations to identify localized indicator sets for grazing effects. Its methodological approach may also be useful

  13. Biological therapeutics

    National Research Council Canada - National Science Library

    Greenstein, Ben; Brook, Daniel A

    2011-01-01

    This introductory textbook covers all the main categories of biological medicines, including vaccines, hormonal preparations, drugs for rheumatoid arthritis and other connective tissue diseases, drugs...

  14. Data resources for range-wide assessment of livestock grazing across the sagebrush biome

    Science.gov (United States)

    Assal, T.J.; Veblen, K.E.; Farinha, M.A.; Aldridge, Cameron L.; Casazza, Michael L.; Pyke, D.A.

    2012-01-01

    The data contained in this series were compiled, modified, and analyzed for the U.S. Geological Survey (USGS) report "Range-Wide Assessment of Livestock Grazing Across the Sagebrush Biome." This report can be accessed through the USGS Publications Warehouse (online linkage: http://pubs.usgs.gov/of/2011/1263/). The dataset contains spatial and tabular data related to Bureau of Land Management (BLM) Grazing Allotments. We reviewed the BLM national grazing allotment spatial dataset available from the GeoCommunicator National Integrated Land System (NILS) website in 2007 (http://www.geocommunicator.gov). We identified several limitations in those data and learned that some BLM State and/or field offices had updated their spatial data to rectify these limitations, but maintained the data outside of NILS. We contacted appropriate BLM offices (State or field, 25 in all) to obtain the most recent data, assessed the data, established a data development protocol, and compiled data into a topologically enforced dataset throughout the area of interest for this project (that is, the pre-settlement distribution of Greater Sage-Grouse in the Western United States). The final database includes three spatial datasets: Allotments (BLM Grazing Allotments), OUT_Polygons (nonallotment polygons used to ensure topology), and Duplicate_Polygon_Allotments. See Appendix 1 of the aforementioned report for complete methods. The tabular data presented here consists of information synthesized by the Land Health Standard (LHS) analysis (Appendix 2), and data obtained from the BLM Rangeland Administration System (http://www.blm.gov/ras/). In 2008, available LHS data for all allotments in all regions were compiled by BLM in response to a Freedom of Information Act (FOIA) request made by a private organization. The BLM provided us with a copy of these data. These data provided three major types of information that were of interest: (1) date(s) (if any) of the most recent LHS evaluation for each

  15. Determining the resilience of carbon dynamics in semi-arid biomes of the Southwestern US to severe drought and altered rainfall patterns

    Science.gov (United States)

    Litvak, M. E.; Krofcheck, D. J.; Hilton, T. W.; Fox, A. M.; Osuna, J. L.

    2011-12-01

    Water is critically important for biotic processes in semi-arid ecosystems and 2011 is developing as one of the most severe drought years on record for many parts of the Southwestern US. To quantify the impact of this severe drought on regional carbon and energy balance, we need a more detailed understanding of how water limitation alters ecosystem processes across a range of semi-arid biomes. We quantified the impact of severe drought and changes in both the quantity and distribution of precipitation on ecosystem biotic structure and function across the range of biomes represented in the NM elevation gradient network (desert grassland, creosote shrubland, juniper savanna, piñon-juniper woodland, ponderosa pine forest and subalpine mixed conifer forest). We compared how daily, seasonal and annual carbon and energy balance and their components in each of these biomes respond to changes in rainfall patterns using continuous measurements of carbon, water and energy exchange and associated measurements in each of these biomes during a 5 year period (2006-2011) that included a severe drought, and large variability in both winter precipitation and the timing and intensity of the monsoon. To understand the underlying mechanisms, we used time series of radiation absorbed by vegetation, surface albedo, soil moisture storage, phenology, gross primary productivity (GPP), ecosystem respiration (Re), and WorldView-2 images acquired pre- and post-monsoon in each of these biomes. In all of the biomes except the desert grassland site, the strength and timing of both winter and monsoon precipitation are important controls over carbon and energy dynamics in this region, though we see site-specific sensitivities across the elevation gradient. Over the past 5 years, carbon dynamics in the desert grassland site appears to be decoupled from winter precipitation. In addition, carbon dynamics in disturbed grassland and pinon-juniper ecosystems were more sensitive to severe drought than

  16. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  17. central t

    Directory of Open Access Journals (Sweden)

    Manuel R. Piña Monarrez

    2007-01-01

    Full Text Available Dado que la Regresión Ridge (RR, es una estimación sesgada que parte de la solución de la regresión de Mínimos Cuadrados (MC, es vital establecer las condiciones para las que la distribución central t de Student que se utiliza en la prueba de hipótesis en MC, sea también aplicable a la regresión RR. La prueba de este importante resultado se presenta en este artículo.

  18. Central sleep apnea

    Science.gov (United States)

    Sleep apnea - central; Obesity - central sleep apnea; Cheyne-Stokes - central sleep apnea; Heart failure - central sleep apnea ... Central sleep apnea results when the brain temporarily stops sending signals to the muscles that control breathing. The condition ...

  19. Computational biology

    DEFF Research Database (Denmark)

    Hartmann, Lars Røeboe; Jones, Neil; Simonsen, Jakob Grue

    2011-01-01

    Computation via biological devices has been the subject of close scrutiny since von Neumann’s early work some 60 years ago. In spite of the many relevant works in this field, the notion of programming biological devices seems to be, at best, ill-defined. While many devices are claimed or proved t...

  20. Mesoscopic biology

    Indian Academy of Sciences (India)

    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological ...

  1. Science framework for conservation and restoration of the sagebrush biome: Linking the Department of the Interior’s Integrated Rangeland Fire Management Strategy to long-term strategic conservation actions

    Science.gov (United States)

    J.C. Chambers; J.L. Beck; J.B. Bradford; J. Bybee; S. Campbell; J. Carlson; T.J. Christiansen; K.J. Clause; G. Collins; M.R. Crist; J.B. Dinkins; K.E. Doherty; F. Edwards; S. Espinosa; K.A. Griffin; P. Griffin; J.R. Haas; S.E. Hanser; D.W. Havlina; K.F. Henke; J.D. Hennig; L.A. Joyce; F.M. Kilkenny; S.M. Kulpa; L.L. Kurth; J.D. Maestas; M. Manning; K.E. Mayer; B.A. Mealor; C. McCarthy; M. Pellant; M.A. Perea; K.L. Prentice; D.A. Pyke; L.A. Wiechman; A. Wuenschel

    2017-01-01

    The Science Framework is intended to link the Department of the Interior’s Integrated Rangeland Fire Management Strategy with long-term strategic conservation actions in the sagebrush biome. The Science Framework provides a multiscale approach for prioritizing areas for management and determining effective management strategies within the sagebrush biome. The emphasis...

  2. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  3. Managing biological diversity

    Science.gov (United States)

    Samson, Fred B.; Knopf, Fritz L.

    1993-01-01

    viewing issues across biological, spatial, and temporal scales (Knopf and Smith 1992), natural resource managers find much conflicting information in the literature on strategies and programs for the conservation of biological diversity (Ehrlich 1992). Moreover, recommendations provided in much of the published information available for planning or decisions not only can be debated but may prove counterproductive if implemented. Current operational efforts beg for clearer focus on fundamental concepts central to daily decisions that impact native biological diversity. Recognizing that many biologists would provide different council and at the risk of oversimplification, we offer the following 4 topical issues as fundamental guidance to wise conservation action. These recommendations are based on our collective experiences working within conservation agencies since our original, collaborative essay (Samson and Knopf 1982). They are offered as initial, rather than authoritative, steps to better align research and management decisions with what we perceive as the critical issues in conserving biological diversity at the landscape and ecosystem levels of resolution.

  4. Central hypothyroidism

    Directory of Open Access Journals (Sweden)

    Vishal Gupta

    2011-01-01

    Full Text Available Central hypothyroidism is defined as hypothyroidism due to insufficient stimulation by thyroid stimulating hormone (TSH of an otherwise normal thyroid gland. It has an estimated prevalence of approximately 1 in 80,000 to 1 in 120,000. It can be secondary hypothyroidism (pituitary or tertiary hypothyroidism (hypothalamus in origin. In children, it is usually caused by craniopharyngiomas or previous cranial irradiation for brain tumors or hematological malignancies. In adults, it is usually due to pituitary macroadenomas, pituitary surgeries or post-irradiation. Fatigue and peripheral edema are the most specific clinical features. Diagnosis is established by the presence of normal to low-normal TSH on the background of low-normal thyroid hormones, confirmed by the thyrotropin releasing hormone stimulation test. Therapy includes use of levothyroxine titrated to improvement in symptomology and keeping free T4 in the upper limit of normal reference range.

  5. Biological desulfurisation

    Energy Technology Data Exchange (ETDEWEB)

    Arena, B.J. [UOP LLC (United States); Benschop, A.; Janssen, A. [Paques Natural Solutions (Netherlands); Kijlstra, S. [Shell Global Solutions (Netherlands)

    2001-03-01

    This article focuses on the biological THIOPAQ process for removing hydrogen sulphide from refinery gases and recovering elemental sulphur. Details are given of the process which absorbs hydrogen sulphide-containing gas in alkaline solution prior to oxidation of the dissolved sulphur to elemental sulphur in a THIOPAQ aerobic biological reactor, with regeneration of the caustic solution. Sulphur handling options including sulphur wash, the drying of the sulphur cake, and sulphur smelting by pressure liquefaction are described. Agricultural applications of the biologically recovered sulphur, and application of the THIOPAQ process to sulphur recovery are discussed.

  6. Simulating carbon and water fluxes at Arctic and boreal ecosystems in Alaska by optimizing the modified BIOME-BGC with eddy covariance data

    Science.gov (United States)

    Ueyama, M.; Kondo, M.; Ichii, K.; Iwata, H.; Euskirchen, E. S.; Zona, D.; Rocha, A. V.; Harazono, Y.; Nakai, T.; Oechel, W. C.

    2013-12-01

    To better predict carbon and water cycles in Arctic ecosystems, we modified a process-based ecosystem model, BIOME-BGC, by introducing new processes: change in active layer depth on permafrost and phenology of tundra vegetation. The modified BIOME-BGC was optimized using an optimization method. The model was constrained using gross primary productivity (GPP) and net ecosystem exchange (NEE) at 23 eddy covariance sites in Alaska, and vegetation/soil carbon from a literature survey. The model was used to simulate regional carbon and water fluxes of Alaska from 1900 to 2011. Simulated regional fluxes were validated with upscaled GPP, ecosystem respiration (RE), and NEE based on two methods: (1) a machine learning technique and (2) a top-down model. Our initial simulation suggests that the original BIOME-BGC with default ecophysiological parameters substantially underestimated GPP and RE for tundra and overestimated those fluxes for boreal forests. We will discuss how optimization using the eddy covariance data impacts the historical simulation by comparing the new version of the model with simulated results from the original BIOME-BGC with default ecophysiological parameters. This suggests that the incorporation of the active layer depth and plant phenology processes is important to include when simulating carbon and water fluxes in Arctic ecosystems.

  7. Assessment of water pollution in the Brazilian Pampa biome by means of stress biomarkers in tadpoles of the leaf frog Phyllomedusa iheringii (Anura: Hylidae

    Directory of Open Access Journals (Sweden)

    TG Santos

    2015-06-01

    Full Text Available The Brazilian Pampa biome is currently under constant threat due to increase of agriculture and improper management of urban effluents. Studies with a focus on the assessment of impacts caused by human activities in this biome are scarce. In the present study, we measured stress-related biomarkers in tadpoles of the leaf frog Phyllomedusa iheringii, an endemic species to the Pampa biome, and tested its suitability as a bioindicator for the assessment of potential aquatic contamination in selected ponds (S1 and S2 nearby agricultural areas in comparison to a reference site. A significant decrease in acetylcholinesterase activity was observed in S2 when compared to S1 and reference. The levels of total-hydroperoxides were increased in S2 site. In parallel, increased activity of the antioxidant enzymes catalase, superoxide dismutase and glutathione S-transferase were observed in S2 when compared to S1 and reference. Further studies are necessary in order to correlate the changes observed here with different chemical stressors in water, as well as to elucidate mechanisms of toxicity induced by pesticides in amphibian species endemic to the Pampa biome. Nevertheless, our study validates Phyllomedusa iheringii as a valuable bioindicator in environmental studies.

  8. Assessment of water pollution in the Brazilian Pampa biome by means of stress biomarkers in tadpoles of the leaf frog Phyllomedusa iheringii (Anura: Hylidae).

    Science.gov (United States)

    Santos, T G; Melo, R; Costa-Silva, D G; Nunes, Mem; Rodrigues, N R; Franco, J L

    2015-01-01

    The Brazilian Pampa biome is currently under constant threat due to increase of agriculture and improper management of urban effluents. Studies with a focus on the assessment of impacts caused by human activities in this biome are scarce. In the present study, we measured stress-related biomarkers in tadpoles of the leaf frog Phyllomedusa iheringii, an endemic species to the Pampa biome, and tested its suitability as a bioindicator for the assessment of potential aquatic contamination in selected ponds (S1 and S2) nearby agricultural areas in comparison to a reference site. A significant decrease in acetylcholinesterase activity was observed in S2 when compared to S1 and reference. The levels of total-hydroperoxides were increased in S2 site. In parallel, increased activity of the antioxidant enzymes catalase, superoxide dismutase and glutathione S-transferase were observed in S2 when compared to S1 and reference. Further studies are necessary in order to correlate the changes observed here with different chemical stressors in water, as well as to elucidate mechanisms of toxicity induced by pesticides in amphibian species endemic to the Pampa biome. Nevertheless, our study validates Phyllomedusa iheringii as a valuable bioindicator in environmental studies.

  9. Adapting a rapid assessment protocol to environmentally assess palm swamp (Veredas) springs in the Cerrado biome, Brazil.

    Science.gov (United States)

    Guimarães, Ariane; de Lima Rodrigues, Aline Sueli; Malafaia, Guilherme

    2017-10-30

    The exploitation and degradation of natural environments exert intense pressure on important ecosystems worldwide. Thus, it is necessary developing or adapting assessment methods to monitor environmental changes and to generate results to be applied to environmental management programs. The Brazilian Veredas (phytophysiognomies typical to the Cerrado biome) are threatened by several human activities; thus, the aim of the present study is to adapt a rapid assessment protocol (RAP) to be applied to Veredas springs, by using the upper course of the Vai-e-Vem stream watershed (Ipameri County, Goiás State, Brazil). Therefore, several springs in the study site were visited and 11 of them were considered Veredas springs. After the RAP was adapted, the instrument was validated and used to environmentally assess the springs in order to demonstrate its applicability. The present study has provided an instrument of option to monitor Veredas springs.

  10. Circulation of canine parvovirus among dogs living in human-wildlife interface in the Atlantic forest biome, Brazil

    Directory of Open Access Journals (Sweden)

    Flávia V. Vieira

    2017-12-01

    Full Text Available Despite of the role of domestic dogs as reservoirs for threatening viral diseases for wild carnivores, few studies have focused to identify circulation of viruses among dogs living in human/wildlife interfaces. To identify canine parvovirus (CPV types circulating in dogs living in an Atlantic forest biome, faecal samples (n = 100 were collected at the same period (one week corresponding to each of four areas, during 2014 to 2016 and corresponded to 100 different individuals. CPV was isolated in cell culture from 67 out 100 (67% samples from healthy dogs. Cytopathic effects were characterized by total or partial cell culture lysis. Genome sequences of CPV-2a (10%, CPV-2b (7% and CPV-2c (50% were concomitantly detected by PCR and nucleotide sequencing. The current study addresses the importance of monitoring CPV circulation among dogs presenting potential contact with wildlife species.

  11. La asignación de recursos y la investigación biomédica

    Directory of Open Access Journals (Sweden)

    Artells Herrero, Juan José

    2001-10-01

    Full Text Available Not available

    Nadie parece cuestionar, al menos desde el punto de vista teórico, que la Investigación junto con la Docencia, son compañeros inseparables del objetivo último de un Sistema Sanitario moderno y consolidado, que no es otro que el de dar respuesta eficiente a las expectativas de salud de las personas. Aspectos como asignación de recursos, priorización, cadena de valor, coste de oportunidad, necesidad, contrato programa, producción conjunta, bien público, reputación, riesgo y especificidad de activos, se tratan a lo largo del artículo. Los recursos que a tal fin se asignen, la valoración de prioridades y el análisis conceptual de lo que cabe considerar como investigación biomédica, son objeto de tratamiento en esta exposición.

  12. Procedimiento para la obtención de células madre mesenquimales para uso biomédico

    OpenAIRE

    Menéndez, Pablo; Ligero, G.; Sánchez, L.; Gutiérrez-Aranda, I.; Rodríguez-González, René; Rubio-Amador, Ruth; Bueno, C.; Ramos-Mejía, Verónica; Delgado, M.

    2010-01-01

    [ES] Procedimiento de obtención de células madre mesenquimales para uso biomédico. La presente invención describe un procedimiento de obtención de CMMs a partir de cultivos de PSC, mediante la inhibición de la via de señalización SMAD2/3, preferentemente con el inhibidor quimico 4-[4-(1,3- Benzodioxol-5-il)-5-(2-piridinil)-1 H-imidazol-2-il] benzamida. Las PSCCMMs descritas en la presente invención, son capaces de diferenciarse a células de la línea osteogénica, condrogénica y adi...

  13. Systems Biology

    Indian Academy of Sciences (India)

    IAS Admin

    study and understand the function of biological systems, particu- larly, the response of such .... understand the organisation and behaviour of prokaryotic sys- tems. ... relationship of the structure of a target molecule to its ability to bind a certain ...

  14. A Changing Number of Alternative States in the Boreal Biome: Reproducibility Risks of Replacing Remote Sensing Products.

    Science.gov (United States)

    Xu, Chi; Holmgren, Milena; Van Nes, Egbert H; Hirota, Marina; Chapin, F Stuart; Scheffer, Marten

    2015-01-01

    Publicly available remote sensing products have boosted science in many ways. The openness of these data sources suggests high reproducibility. However, as we show here, results may be specific to versions of the data products that can become unavailable as new versions are posted. We focus on remotely-sensed tree cover. Recent studies have used this public resource to detect multi-modality in tree cover in the tropical and boreal biomes. Such patterns suggest alternative stable states separated by critical tipping points. This has important implications for the potential response of these ecosystems to global climate change. For the boreal region, four distinct ecosystem states (i.e., treeless, sparse and dense woodland, and boreal forest) were previously identified by using the Collection 3 data of MODIS Vegetation Continuous Fields (VCF). Since then, the MODIS VCF product has been updated to Collection 5; and a Landsat VCF product of global tree cover at a fine spatial resolution of 30 meters has been developed. Here we compare these different remote-sensing products of tree cover to show that identification of alternative stable states in the boreal biome partly depends on the data source used. The updated MODIS data and the newer Landsat data consistently demonstrate three distinct modes around similar tree-cover values. Our analysis suggests that the boreal region has three modes: one sparsely vegetated state (treeless), one distinct 'savanna-like' state and one forest state, which could be alternative stable states. Our analysis illustrates that qualitative outcomes of studies may change fundamentally as new versions of remote sensing products are used. Scientific reproducibility thus requires that old versions remain publicly available.

  15. Population Genetic Structure of Cnesterodon decemmaculatus (Poeciliidae): A Freshwater Look at the Pampa Biome in Southern South America.

    Science.gov (United States)

    Ramos-Fregonezi, Aline M C; Malabarba, Luiz R; Fagundes, Nelson J R

    2017-01-01

    The Pampas is a Neotropical biome formed primarily by low altitude grasslands and encompasses the southernmost portion of Brazil, Uruguay, and part of Argentina. Despite the high level of endemism, and its significant environmental heterogeneity, Pampean species are underrepresented in phylogeographic studies, especially aquatic organisms. The Pampean hydrological system resulted from a long history of tectonism, climate, and sea level changes since the Neogene. In this study, we examined the population genetic structure of Cnesterodon decemmaculatus , a freshwater fish species that occurs throughout most of the Pampa biome. We characterized mitochondrial and autosomal genetic lineages in populations sampled from Southern Brazil and Uruguay to investigate (1) the correspondence between current drainage systems and evolutionary lineages, (2) the demographic history for each genetic lineage, and (3) the temporal depth of these lineages. Overall, we found that the major evolutionary lineages in this species are strongly related to the main Pampean drainage systems, even though stream capture events may have affected the distribution of genetic lineages among drainages. There was evidence for recent population growth in the lineages occupying drainages closest to the shore, which may indicate the effect of quaternary sea-level changes. In general, divergence time estimates among evolutionary lineages were shallow, ranging from 20,000 to 800,000 years before present, indicating a geologically recent history for this group, as previously reported in other Pampean species. A Bayesian phylogeographical reconstruction suggested that an ancestral lineage probably colonized the Uruguay River Basin, and then expanded throughout the Pampas. This evolutionary scenario may represent useful starting models for other freshwater species having a similar distribution.

  16. Optimizing selective cutting strategies for maximum carbon stocks and yield of Moso bamboo forest using BIOME-BGC model.

    Science.gov (United States)

    Mao, Fangjie; Zhou, Guomo; Li, Pingheng; Du, Huaqiang; Xu, Xiaojun; Shi, Yongjun; Mo, Lufeng; Zhou, Yufeng; Tu, Guoqing

    2017-04-15

    The selective cutting method currently used in Moso bamboo forests has resulted in a reduction of stand productivity and carbon sequestration capacity. Given the time and labor expense involved in addressing this problem manually, simulation using an ecosystem model is the most suitable approach. The BIOME-BGC model was improved to suit managed Moso bamboo forests, which was adapted to include age structure, specific ecological processes and management measures of Moso bamboo forest. A field selective cutting experiment was done in nine plots with three cutting intensities (high-intensity, moderate-intensity and low-intensity) during 2010-2013, and biomass of these plots was measured for model validation. Then four selective cutting scenarios were simulated by the improved BIOME-BGC model to optimize the selective cutting timings, intervals, retained ages and intensities. The improved model matched the observed aboveground carbon density and yield of different plots, with a range of relative error from 9.83% to 15.74%. The results of different selective cutting scenarios suggested that the optimal selective cutting measure should be cutting 30% culms of age 6, 80% culms of age 7, and all culms thereafter (above age 8) in winter every other year. The vegetation carbon density and harvested carbon density of this selective cutting method can increase by 74.63% and 21.5%, respectively, compared with the current selective cutting measure. The optimized selective cutting measure developed in this study can significantly promote carbon density, yield, and carbon sink capacity in Moso bamboo forests. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Scale and the isotopic record of C4 plants in pedogenic carbonate: from the biome to the rhizospere.

    Energy Technology Data Exchange (ETDEWEB)

    Monger, Dr. H Curtis [New Mexico State University, Las Cruces; Cole, David R [ORNL; Buck, Dr. Brenda [University of Nevada, Las Vegas; Gallegos, Robert [Sant fe Water Division

    2009-01-01

    The 13C/12C ratio in pedogenic carbonate (i.e., CaCO3 formed in soil) is a significant tool for investigating C4 biomes of the past. However, the paleoecological meaning of d13C values in pedogenic carbonate can change with the scale at which one considers the data. We describe studies of modern soils, fossil soils, and vegetation change in the Chihuahuan Desert of North America and elsewhere that reveal four scales important for paleoecologic interpretations. (1) At the broadest scale, the biome scale (hundreds to millions of km2), an isotopic record interpreted as C3 vegetation replacing C4 grasslands may indicate invading C3 woody shrubs instead of expanding C3 forests (a common interpretation). (2) At the landscape scale (several tens of m2 to hundreds of km2), the accuracy of scaling up paleoclimatic interpretations to a regional level is affected by the landform containing the isotopic record. (3) At the soil-profile scale (cm2 to m2), soil profiles with multiple generations of carbonate mixed together have a lower-resolution paleoecologic record than soil profiles repeatedly buried. (4) At the rhizosphere scale (lm2 to cm2), carbonate formed on roots lack the 14 17 enrichment observed at broader scales, revealing different fractionation processes at different scales. A multi-scale approach in dealing with d13C in pedogenic carbonate will increase the accuracy of paleoecologic interpretations and understanding of soil geomorphic climatic interactions that affect boundaries between C4 and C3 vegetation.

  18. Population Genetic Structure of Cnesterodon decemmaculatus (Poeciliidae: A Freshwater Look at the Pampa Biome in Southern South America

    Directory of Open Access Journals (Sweden)

    Aline M. C. Ramos-Fregonezi

    2017-12-01

    Full Text Available The Pampas is a Neotropical biome formed primarily by low altitude grasslands and encompasses the southernmost portion of Brazil, Uruguay, and part of Argentina. Despite the high level of endemism, and its significant environmental heterogeneity, Pampean species are underrepresented in phylogeographic studies, especially aquatic organisms. The Pampean hydrological system resulted from a long history of tectonism, climate, and sea level changes since the Neogene. In this study, we examined the population genetic structure of Cnesterodon decemmaculatus, a freshwater fish species that occurs throughout most of the Pampa biome. We characterized mitochondrial and autosomal genetic lineages in populations sampled from Southern Brazil and Uruguay to investigate (1 the correspondence between current drainage systems and evolutionary lineages, (2 the demographic history for each genetic lineage, and (3 the temporal depth of these lineages. Overall, we found that the major evolutionary lineages in this species are strongly related to the main Pampean drainage systems, even though stream capture events may have affected the distribution of genetic lineages among drainages. There was evidence for recent population growth in the lineages occupying drainages closest to the shore, which may indicate the effect of quaternary sea-level changes. In general, divergence time estimates among evolutionary lineages were shallow, ranging from 20,000 to 800,000 years before present, indicating a geologically recent history for this group, as previously reported in other Pampean species. A Bayesian phylogeographical reconstruction suggested that an ancestral lineage probably colonized the Uruguay River Basin, and then expanded throughout the Pampas. This evolutionary scenario may represent useful starting models for other freshwater species having a similar distribution.

  19. Scale and the isotopic record of C4 plants in pedogenic carbonate: from the biome to the rhizosphere

    Energy Technology Data Exchange (ETDEWEB)

    Monger, Dr. H Curtis [New Mexico State University, Las Cruces; Cole, David [Ohio State University; Buck, Dr. Brenda [University of Nevada, Las Vegas; Gallegos, Robert [Sant fe Water Division

    2009-01-01

    The 13C/12C ratio in pedogenic carbonate (i.e., CaCO3 formed in soil) is a significant tool for investigating C4 biomes of the past. However, the paleoecological meaning of d13C values in pedogenic carbonate can change with the scale at which one considers the data. We describe studies of modern soils, fossil soils, and vegetation change in the Chihuahuan Desert of North America and elsewhere that reveal four scales important for paleoecologic interpretations. (1) At the broadest scale, the biome scale (hundreds to millions of km2), an isotopic record interpreted as C3 vegetation replacing C4 grasslands may indicate invading C3 woody shrubs instead of expanding C3 forests (a common interpretation). (2) At the landscape scale (several tens of m2 to hundreds of km2), the accuracy of scaling up paleoclimatic interpretations to a regional level is affected by the landform containing the isotopic record. (3) At the soil-profile scale (cm2 to m2), soil profiles with multiple generations of carbonate mixed together have a lower-resolution paleoecologic record than soil profiles repeatedly buried. (4) At the rhizosphere scale (lm2 to cm2), carbonate formed on roots lack the 14 17 enrichment observed at broader scales, revealing different fractionation processes at different scales. A multi-scale approach in dealing with d13C in pedogenic carbonate will increase the accuracy of paleoecologic interpretations and understanding of soil geomorphic climatic interactions that affect boundaries between C4 and C3 vegetation.

  20. Decree No 82-1050 of 13 December 1982 creating a Central Service for repression of illicit trading in weapons, munitions, explosive products and nuclear, biological and chemical materials

    International Nuclear Information System (INIS)

    1982-01-01

    The Central Service was set up within the Ministry of the Interior and is responsible for the protection of the State and the national territory against criminal attempts, conspiracies and acts of terrorism and is vested with the necessary powers to discharge its duties. It co-operates with the other departments concerned in the study of measures to prevent unlawful use of weapons and nuclear materials. (NEA) [fr

  1. Investigación biomédica, intereses económicos y divulgación periodística

    Directory of Open Access Journals (Sweden)

    Roberto Germán Zurriaráin

    2017-01-01

    Full Text Available Este artículo pretende afirmar que toda investigación, especialmente la biomédica, para que sea precisamente tal, tiene que poseer una dimensión ética. Y goza de esta dimensión siempre y cuando vaya en beneficio del propio ser humano. Sin ella no se puede hablar de progreso en la investigación biomédica. Luego, solamente se puede denominar “progreso” si hablamos de una investigación que vaya en beneficio de cada uno de los seres humanos. Así es, la investigación biomédica se tiene que traducir en un avanzar del ser humano en humanidad. Pero desgracia- damente muchas veces no ocurre esto. Se llama investigación biomédica a todo, independien- temente de que posea o no una dimensión ética, considerada esta como una instancia exterior. Esta dimensión, insertada en la propia investigación biomédica, es sustituida por otros intere- ses, sobre todo de carácter económico, especialmente en reproducción humana artificial. Así también, los medios de comunicación social hacen eco de este tipo de estudios en biomedicina. Pero muchas veces los medios buscan más las emociones del espectador que su responsabilidad por transmitir noticias con rigor y veracidad.

  2. Synthetic biology: engineering molecular computers

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    Complicated systems cannot survive the rigors of a chaotic environment, without balancing mechanisms that sense, decide upon and counteract the exerted disturbances. Especially so with living organisms, forced by competition to incredible complexities, escalating also their self-controlling plight. Therefore, they compute. Can we harness biological mechanisms to create artificial computing systems? Biology offers several levels of design abstraction: molecular machines, cells, organisms... ranging from the more easily-defined to the more inherently complex. At the bottom of this stack we find the nucleic acids, RNA and DNA, with their digital structure and relatively precise interactions. They are central enablers of designing artificial biological systems, in the confluence of engineering and biology, that we call Synthetic biology. In the first part, let us follow their trail towards an overview of building computing machines with molecules -- and in the second part, take the case study of iGEM Greece 201...

  3. Teaching Molecular Biology with Microcomputers.

    Science.gov (United States)

    Reiss, Rebecca; Jameson, David

    1984-01-01

    Describes a series of computer programs that use simulation and gaming techniques to present the basic principles of the central dogma of molecular genetics, mutation, and the genetic code. A history of discoveries in molecular biology is presented and the evolution of these computer assisted instructional programs is described. (MBR)

  4. [Biological agents].

    Science.gov (United States)

    Amano, Koichi

    2009-03-01

    There are two types of biological agents for the treatment of rheumatoid arthritis (RA); monoclonal antibodies and recombinant proteins. Among the latter, etanercept, a recombinant fusion protein of soluble TNF receptor and IgG was approved in 2005 in Japan. The post-marketing surveillance of 13,894 RA patients revealed the efficacy and safety profiles of etanercept in the Japanese population, as well as overseas studies. Abatacept, a recombinant fusion protein of CTLA4 and IgG, is another biological agent for RA. Two clinical trials disclosed the efficacy of abatacept for difficult-to-treat patients: the AIM for MTX-resistant cases and the ATTAIN for patients who are resistant to anti-TNF. The ATTEST trial suggested abatacept might have more acceptable safety profile than infliximab. These biologics are also promising for the treatment of RA for not only relieving clinical symptoms and signs but retarding structural damage.

  5. Biological preconcentrator

    Science.gov (United States)

    Manginell, Ronald P [Albuquerque, NM; Bunker, Bruce C [Albuquerque, NM; Huber, Dale L [Albuquerque, NM

    2008-09-09

    A biological preconcentrator comprises a stimulus-responsive active film on a stimulus-producing microfabricated platform. The active film can comprise a thermally switchable polymer film that can be used to selectively absorb and desorb proteins from a protein mixture. The biological microfabricated platform can comprise a thin membrane suspended on a substrate with an integral resistive heater and/or thermoelectric cooler for thermal switching of the active polymer film disposed on the membrane. The active polymer film can comprise hydrogel-like polymers, such as poly(ethylene oxide) or poly(n-isopropylacrylamide), that are tethered to the membrane. The biological preconcentrator can be fabricated with semiconductor materials and technologies.

  6. Improved clonality detection in Hodgkin lymphoma using a semi-nested modification of the BIOMED-2 PCR assay for IGH and IGK rearrangements: A paraffin-embedded tissue study.

    Science.gov (United States)

    Han, Shusen; Masaki, Ayako; Sakamoto, Yuma; Takino, Hisashi; Murase, Takayuki; Iida, Shinsuke; Inagaki, Hiroshi

    2018-05-01

    The BIOMED-2 PCR protocols targeting IGH and IGK genes may be useful for detecting clonality in Hodgkin lymphoma (HL). The clonality detection rates, however, have not been very high with these methods using paraffin-embedded tumor sections. We previously described the usefulness of the semi-nested BIOMED-2 IGH assay in B-cell malignancies. In this study, we devised a novel semi-nested BIOMED-2 IGK assay. Employing 58 cases of classical HL, we carried out the standard BIOMED-2, BIOMED-2 followed by BIOMED-2 re-amplification, and BIOMED-2 followed by semi-nested BIOMED-2, all targeting IGH and IGK, using paraffin-embedded tissues. In both IGH and IGK assays, semi-nested assays yielded significantly higher clonality detection rates than the standard assays and re-amplification assays. Clonality was detected in 13/58 (22.4%) classical HL cases using the standard IGH/IGK assays while it was detected in 38/58 (65.5%) cases using semi-nested IGH/IGK assays. The detection rates were not associated with the HL subtypes, CD30-positive cell density, CD20-positive cell density, or Epstein-Barr virus (EBV) positivity. In conclusion, tumor clonality was detected in nearly two-thirds of classical HL cases using semi-nested BIOMED-2 IGH/IGK assays using paraffin tumor sections. These semi-nested assays may be useful when the standard IGH/IGK assays fail to detect clonality in histopathologically suspected HLs. © 2018 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

  7. A comparative assessment of the biological properties of soils in the cultural and native cenoses of the Central Caucasus (using the example of the Terskii variant of altitudinal zonality in Kabardino-Balkaria)

    Science.gov (United States)

    Gorobtsova, O. N.; Gedgafova, F. V.; Uligova, T. S.; Tembotov, R. Kh.

    2016-01-01

    The biological properties of the most widespread automorphic and hydromorphic soils of cultural and native cenoses in the Terskii variant of the altitudinal zonality (Kabardino-Balkaria) are compared. The data on the humus reserves in the 0- to 20-cm soil layer and those on the carbon content in the microbial biomass calculated on the basis of the results of substrate-induced respiration measurements are presented. The share of carbon in the microbial biomass of the total organic carbon in the soils was determined. Long-term (more than 70 years) farming on the studied soils significantly changed their biological properties. The humus content and its reserves became lower by 25-40%. The physiological activity of the microbial biomass in the cultural soils decreased by more than 60%. Presently, the soils of the cultural cenoses function as an entire natural system, but at a lower level of fertility; the loss of more than 30% of the bioorganic potential (the critical threshold of soil system stability) indicates the disturbance of soil ecological functions, their stability, and the capability of self-restoration.

  8. Biome-Scale Forest Properties in Amazonia Based on Field and Satellite Observations

    Directory of Open Access Journals (Sweden)

    Liana O. Anderson

    2012-05-01

    Full Text Available Amazonian forests are extremely heterogeneous at different spatial scales. This review intends to present the large-scale patterns of the ecosystem properties of Amazonia, and focuses on two parts of the main components of the net primary production: the long-lived carbon pools (wood and short-lived pools (leaves. First, the focus is on forest biophysical properties, and secondly, on the macro-scale leaf phenological patterns of these forests, looking at field measurements and bringing into discussion the recent findings derived from remote sensing dataset. Finally, I discuss the results of the three major droughts that hit Amazonia in the last 15 years. The panorama that emerges from this review suggests that slow growing forests in central and eastern Amazonia, where soils are poorer, have significantly higher above ground biomass and higher wood density, trees are higher and present lower proportions of large-leaved species than stands in northwest and southwest Amazonia. However, the opposite pattern is observed in relation to forest productivity and dynamism, which is higher in western Amazonia than in central and eastern forests. The spatial patterns on leaf phenology across Amazonia are less marked. Field data from different forest formations showed that new leaf production can be unrelated to climate seasonality, timed with radiation, timed with rainfall and/or river levels. Oppositely, satellite images exhibited a large-scale synchronized peak in new leaf production during the dry season. Satellite data and field measurements bring contrasting results for the 2005 drought. Discussions on data processing and filtering, aerosols effects and a combined analysis with field and satellite images are presented. It is suggested that to improve the understanding of the large-scale patterns on Amazonian forests, integrative analyses that combine new technologies in remote sensing and long-term field ecological data are imperative.

  9. Using simulated annealing algorithm to optimize the parameters of Biome-BGC model%利用模拟退火算法优化Biome-BGC模型参数

    Institute of Scientific and Technical Information of China (English)

    张廷龙; 孙睿; 胡波; 冯丽超

    2011-01-01

    生态过程模型建立在明确的机理之上,能够较好地模拟陆地生态系统的行为和特征,但模型众多的参数,成为模型具体应用的瓶颈.本文以Biome-BGC模型为例,采用模拟退火算法,对其生理、生态参数进行优化.在优化过程中,先对待优化参数进行了选择,然后采取逐步优化的方法进行优化.结果表明,使用优化后的参数,模型模拟结果与实际观测更为接近,参数优化能有效地降低模型模拟的不确定性.文中参数优化的过程和方法,可为生态模型的参数识别和优化提供一种实例和思路,有助于生态模型应用区域的扩展.%Ecological process model based on defined mechanism can well simulate the dynamic behaviors and features of terrestrial ecosystem, but could become a bottleneck in application because of numerous parameters needed to be confirmed. In this paper, simulated annealing algorithm was used to optimize the physiological and ecological parameters of Biome-BGC model. The first step was to choose some of these parameters to optimize, and then, gradually optimized these parameters. By using the optimized parameters, the model simulation results were much more close to the observed data, and the parameter optimization could effectively reduce the uncertainty of model simulation. The parameter optimization method used in this paper could provide a case and an idea for the parameter identification and optimization of ecological process models,and also, help to expand the application area of the models.

  10. Environmental biology

    International Nuclear Information System (INIS)

    Tschumi, P.A.

    1981-01-01

    Environmental biology illustrates the functioning of ecosystems and the dynamics of populations with many examples from limnology and terrestrial ecology. On this basis, present environmental problems are analyzed. The present environmental crisis is seen as a result of the failure to observe ecological laws. (orig.) [de

  11. Biological timekeeping

    DEFF Research Database (Denmark)

    Lloyd, David

    2016-01-01

    , the networks that connect differenttime domains and the oscillations, rhythms and biological clocks that coordinate andsynchronise the complexity of the living state.“It is the pattern maintained by this homeostasis, which is the touchstone ofour personal identity. Our tissues change as we live: the food we...

  12. Scaffolded biology.

    Science.gov (United States)

    Minelli, Alessandro

    2016-09-01

    Descriptions and interpretations of the natural world are dominated by dichotomies such as organism vs. environment, nature vs. nurture, genetic vs. epigenetic, but in the last couple of decades strong dissatisfaction with those partitions has been repeatedly voiced and a number of alternative perspectives have been suggested, from perspectives such as Dawkins' extended phenotype, Turner's extended organism, Oyama's Developmental Systems Theory and Odling-Smee's niche construction theory. Last in time is the description of biological phenomena in terms of hybrids between an organism (scaffolded system) and a living or non-living scaffold, forming unit systems to study processes such as reproduction and development. As scaffold, eventually, we can define any resource used by the biological system, especially in development and reproduction, without incorporating it as happens in the case of resources fueling metabolism. Addressing biological systems as functionally scaffolded systems may help pointing to functional relationships that can impart temporal marking to the developmental process and thus explain its irreversibility; revisiting the boundary between development and metabolism and also regeneration phenomena, by suggesting a conceptual framework within which to investigate phenomena of regular hypermorphic regeneration such as characteristic of deer antlers; fixing a periodization of development in terms of the times at which a scaffolding relationship begins or is terminated; and promoting plant galls to legitimate study objects of developmental biology.

  13. Biological digestion

    International Nuclear Information System (INIS)

    Rosevear, A.

    1988-01-01

    This paper discusses the biological degradation of non-radioactive organic material occurring in radioactive wastes. The biochemical steps are often performed using microbes or isolated enzymes in combination with chemical steps and the aim is to oxidise the carbon, hydrogen, nitrogen and sulphur to their respective oxides. (U.K.)

  14. Marine Biology

    Science.gov (United States)

    Dewees, Christopher M.; Hooper, Jon K.

    1976-01-01

    A variety of informational material for a course in marine biology or oceanology at the secondary level is presented. Among the topics discussed are: food webs and pyramids, planktonic blooms, marine life, plankton nets, food chains, phytoplankton, zooplankton, larval plankton and filter feeders. (BT)

  15. New species of Zygoclistron Rehn, 1905 (Insecta: Orthoptera: Acrididae: Copiocerinae) in the central corridor of the Atlantic Forest biome.

    Science.gov (United States)

    Silva, Daniela Santos Martins; Pereira, Marcelo Ribeiro; Domenico, Fernando Campos De; Sperber, Carlos Frankl

    2016-06-17

    Herein we describe a new species of Copiocerinae, Zygoclistron ruschii Silva n. sp., from Atlantic Forest remnants in southeastern Brazil, collected from the Reserva Biológica Augusto Ruschi in the Santa Teresa municipality, Espírito Santo state, Brazil. The diagnosis of this new species is based on phallic complex and terminalia characters.

  16. The ecology of the elephants in the Kasungu National Park, Malawi with specific reference to management of elephant populations in the Brachystegia biome of Southern Central Africa

    NARCIS (Netherlands)

    Jachmann, Hugo

    1984-01-01

    The elephant is one of the most important animals in African Wildlife Management, firstly because it is capable of modifying through cropping. The latter also makes it a prime poaching target. The main problems caused by elephant concern changes in the physiognomy of the habitat with its

  17. The ecology of the elephants in the Kasungu National Park, Malawi with specific reference to management of elephant populations in the Brachystegia biome of Southern Central Africa

    OpenAIRE

    Jachmann, Hugo

    1984-01-01

    The elephant is one of the most important animals in African Wildlife Management, firstly because it is capable of modifying through cropping. The latter also makes it a prime poaching target. The main problems caused by elephant concern changes in the physiognomy of the habitat with its consequences for the population itself and the diversity of plant and animal species in the conservation area. The Kasungu National Park suffers simultaneously from heavy illegal offtake and an elephant probl...

  18. Effect of Compost Application on Some Properties of a Volcanic Soil from Central South Chile Efecto de la Aplicación de Compost sobre Algunas Propiedades de un Suelo Volcánico de La Región Centro-Sur de Chile

    Directory of Open Access Journals (Sweden)

    Pedro José Valarini

    2009-09-01

    Full Text Available Soil compost application is a common soil management practice used by small farmers of Central-South Chile that produces positive effects on soil properties and also promotes presence and activity of arbuscular mycorrhizal fungi (AMF. This fungi form symbiosis with plant roots improving plant nutrition, as well as producing glomalin, a glycoprotein that has been associated with soil aggregation stability. Therefore, the aim of this study was to evaluate, in an Ultisol from Central-South Chile, the effect of different doses of compost on some soil characteristics at the end of the third year of a crop sequence including wheat (Triticum aestivum L., bean (Phaseolus vulgaris L., and grassland (Lolium multiflorum Lam. associated with Trifolium repens L.. Studied soil characteristics included chemical (pH, available-P, organic C, biological (C and N biomass, AMF spore number, root colonization percentage, mycelium length, and glomalin content, as well as physical parameters (water holding capacity [WHC], and water stable aggregates [WSA]. Results showed that, in general, compost application increased soil pH, mycorrizal roots, mycelium length, glomalin levels, and WSA. Significant relationships were found between C and N biomass, C biomass and WSA, C biomass and glomalin, WSA and WHC, among others. Results suggest that compost application to this type of soil is a feasible option as a fertilizer substitute, and a way to avoid soil erosion by small local farmers involved in organic agriculture.La aplicación de compost al suelo, práctica habitual en predios de pequeños agricultores de la región centro-sur de Chile, produce efectos positivos en sus propiedades y promueve la presencia y actividad de los hongos micorrícicos arbusculares (AMF. Estos hongos forman simbiosis con las raíces de las plantas mejorando su nutrición y además producen una glicoproteína llamada glomalina, la cual ha sido relacionada con la estabilidad de los agregados de

  19. Fabricación y propiedades del carburo de silicio biomórfico: maderas cerámicas

    Directory of Open Access Journals (Sweden)

    Varela Feria, F. M.

    2002-08-01

    Full Text Available There is an increasing interest in the fabrication of materials with biomorphic microstructure. In particular, the fabrication of biomorphic ceramics would be of high interest because its high-temperature structural applications. The ceramics presented in this research were fabricated by the pyrolysis and infiltration with molten silicon of wood preforms. The final product is SiC with the same microstructure of the wood precursor. Wood is a natural composite that present an anisotropic porous microstructure with excellent elasticity, strength, and damage tolerance. Some of this properties will remain improved in the ceramic product. Biomorphic ceramics reach high strengths (700 MPa at 1150 oC for biomorphic SiC made from eucalyptus wood. The influence of the wood precursor and fabrication process in the mechanical and microstructural properties has been studied. The correlation microstructure-mechanical properties is discussed, as well as the application of the cellular theory of solids.

    En los últimos años se ha puesto de manifiesto un considerable interés en la fabricación y optimización de materiales de microestructura biomórfica. En particular, la fabricación de cerámicas biomórficas es especialmente importante ya que éstas pueden ser utilizadas en aplicaciones estructurales a temperaturas elevadas. Los materiales objeto de esta investigación se fabrican mediante la pirólisis e infiltración de silicio fundido en preformas de madera. El resultado final es SiC con la misma microestructura que la madera precursora. La madera es un material natural compuesto que presenta una morfología porosa anisotrópica con una excelente elasticidad, resistencia y tolerancia al daño; algunas de estas propiedades se trasladarán y amplificarán al pasar a la cerámica que se elabora a partir de la misma. Se ha estudiado la influencia de la madera seleccionada y el proceso de fabricación en las propiedades mecánicas y microestructurales

  20. Scaling net ecosystem production and net biome production over a heterogeneous region in the western United States

    Directory of Open Access Journals (Sweden)

    D. P. Turner

    2007-08-01

    Full Text Available Bottom-up scaling of net ecosystem production (NEP and net biome production (NBP was used to generate a carbon budget for a large heterogeneous region (the state of Oregon, 2.5×105 km2 in the western United States. Landsat resolution (30 m remote sensing provided the basis for mapping land cover and disturbance history, thus allowing us to account for all major fire and logging events over the last 30 years. For NEP, a 23-year record (1980–2002 of distributed meteorology (1 km resolution at the daily time step was used to drive a process-based carbon cycle model (Biome-BGC. For NBP, fire emissions were computed from remote sensing based estimates of area burned and our mapped biomass estimates. Our estimates for the contribution of logging and crop harvest removals to NBP were from the model simulations and were checked against public records of forest and crop harvesting. The predominately forested ecoregions within our study region had the highest NEP sinks, with ecoregion averages up to 197 gC m−2 yr−1. Agricultural ecoregions were also NEP sinks, reflecting the imbalance of NPP and decomposition of crop residues. For the period 1996–2000, mean NEP for the study area was 17.0 TgC yr−1, with strong interannual variation (SD of 10.6. The sum of forest harvest removals, crop removals, and direct fire emissions amounted to 63% of NEP, leaving a mean NBP of 6.1 TgC yr−1. Carbon sequestration was predominantly on public forestland, where the harvest rate has fallen dramatically in the recent years. Comparison of simulation results with estimates of carbon stocks, and changes in carbon stocks, based on forest inventory data showed generally good agreement. The carbon sequestered as NBP, plus accumulation of forest products in slow turnover pools, offset 51% of the annual emissions of fossil fuel CO2 for the state. State-level NBP dropped below zero in 2002

  1. Biological Motion Cues Trigger Reflexive Attentional Orienting

    Science.gov (United States)

    Shi, Jinfu; Weng, Xuchu; He, Sheng; Jiang, Yi

    2010-01-01

    The human visual system is extremely sensitive to biological signals around us. In the current study, we demonstrate that biological motion walking direction can induce robust reflexive attentional orienting. Following a brief presentation of a central point-light walker walking towards either the left or right direction, observers' performance…

  2. Nonlinear models for fitting growth curves of Nellore cows reared in the Amazon Biome

    Directory of Open Access Journals (Sweden)

    Kedma Nayra da Silva Marinho

    2013-09-01

    Full Text Available Growth curves of Nellore cows were estimated by comparing six nonlinear models: Brody, Logistic, two alternatives by Gompertz, Richards and Von Bertalanffy. The models were fitted to weight-age data, from birth to 750 days of age of 29,221 cows, born between 1976 and 2006 in the Brazilian states of Acre, Amapá, Amazonas, Pará, Rondônia, Roraima and Tocantins. The models were fitted by the Gauss-Newton method. The goodness of fit of the models was evaluated by using mean square error, adjusted coefficient of determination, prediction error and mean absolute error. Biological interpretation of parameters was accomplished by plotting estimated weights versus the observed weight means, instantaneous growth rate, absolute maturity rate, relative instantaneous growth rate, inflection point and magnitude of the parameters A (asymptotic weight and K (maturing rate. The Brody and Von Bertalanffy models fitted the weight-age data but the other models did not. The average weight (A and growth rate (K were: 384.6±1.63 kg and 0.0022±0.00002 (Brody and 313.40±0.70 kg and 0.0045±0.00002 (Von Bertalanffy. The Brody model provides better goodness of fit than the Von Bertalanffy model.

  3. [Biologics and mycobacterial diseases].

    Science.gov (United States)

    Tsuyuguchi, Kazunari; Matsumoto, Tomoshige

    2013-03-01

    developing TB. Lastly, Dr. Matsumoto stressed the risk of discontinuing TNF-alpha inhibitor during treatment for tuberculosis. He showed from his clinical experience that TNF-alpha inhibitor can be safely used in active TB patient receiving effective antituberculosis chemotherapy and it is even more effective for prevention of paradoxical response. Active discussion was done about the four topics, including the matter beyond present guidelines. We hope these discussions will form the basis for the establishment of new guideline for the management of mycobacterial disease when using immunosuppressive agents including biologics. 1. The risk of developing tuberculosis (TB) and situations of screening for TB risk at administration of biologics-the case of rheumatoid arthritis: Shigeto TOHMA (Clinical Research Center for Allergy and Rheumatology, National Hospital Organization Sagamihara National Hospital) We calculated the standardized incidence ratio (SIR) of TB from the clinical data on National Database of Rheumatic Diseases by iR-net in Japan (NinJa) and compared with the SIR of TB from the data of the post-marketing surveillances of five biologics. Among 43584 patient-years, forty patients developed TB. The SIR of TB in NinJa was 4.34 (95%CI: 3.00-5.69). According to the post-marketing surveillances of 5 biologics, the SIR of TB were 3.62-34.4. The incidence of TB in patients with RA was higher than general population in Japan, and was increased more by some biologics. We have to recognize the risk of TB when we start biologics therapy to patients with RA. Although the frequency of implementation of QuantiFERON test (QFT) had gradually increased, it was still limited to 41%. In order to predict the risk of developing TB and to prevent TB, it might be better to check all RA patients by QFT at time time of biologics administration. 2. Biologics and nontuberculous mycobacterial diseases: Hitoshi TOKUDA (Social Insurance Central General Hospital) Several topics about the

  4. Biological radioprotector

    International Nuclear Information System (INIS)

    Stefanescu, Ioan; Titescu, Gheorghe; Tamaian, Radu; Haulica, Ion; Bild, Walther

    2002-01-01

    According to the patent description, the biological radioprotector is deuterium depleted water, DDW, produced by vacuum distillation with an isotopic content lower than natural value. It appears as such or in a mixture with natural water and carbon dioxide. It can be used for preventing and reducing the ionizing radiation effects upon humans or animal organisms, exposed therapeutically, professionally or accidentally to radiation. The most significant advantage of using DDW as biological radioprotector results from its way of administration. Indeed no one of the radioprotectors currently used today can be orally administrated, what reduces the patients' compliance to prophylactic administrations. The biological radioprotector is an unnoxious product obtained from natural water, which can be administrated as food additive instead of drinking water. Dose modification factor is according to initial estimates around 1.9, what is a remarkable feature when one takes into account that the product is toxicity-free and side effect-free and can be administrated prophylactically as a food additive. A net radioprotective action of the deuterium depletion was evidenced experimentally in laboratory animals (rats) hydrated with DDW of 30 ppm D/(D+H) concentration as compared with normally hydrated control animals. Knowing the effects of irradiation and mechanisms of the acute radiation disease as well as the effects of administration of radiomimetic chemicals upon cellular lines of fast cell division, it appears that the effects of administrating DDW result from stimulation of the immunity system. In conclusion, the biological radioprotector DDW presents the following advantages: - it is obtained from natural products without toxicity; - it is easy to be administrated as a food additive, replacing the drinking water; - besides radioprotective effects, the product has also immunostimulative and antitumoral effects

  5. Network Reconstruction of Dynamic Biological Systems

    OpenAIRE

    Asadi, Behrang

    2013-01-01

    Inference of network topology from experimental data is a central endeavor in biology, since knowledge of the underlying signaling mechanisms a requirement for understanding biological phenomena. As one of the most important tools in bioinformatics area, development of methods to reconstruct biological networks has attracted remarkable attention in the current decade. Integration of different data types can lead to remarkable improvements in our ability to identify the connectivity of differe...

  6. Marine biology

    International Nuclear Information System (INIS)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index

  7. Testing the applicability of BIOME-BGC to simulate beech gross primary production in Europe using a new continental weather dataset

    DEFF Research Database (Denmark)

    Chiesi, Marta; Chirici, Gherardo; Marchetti, Marco

    2016-01-01

    A daily 1-km Pan-European weather dataset can drive the BIOME-BGC model for the estimation of current and future beech gross primary production (GPP). Annual beech GPP is affected primarily by spring temperature and more irregularly by summer water stress.The spread of beech forests in Europe...... forest ecosystems having different climatic conditions where the eddy covariance technique is used to measure water and carbon fluxes. The experiment is in three main steps. First, the accuracy of BIOME-BGC GPP simulations is assessed through comparison with flux observations. Second, the influence...... of two major meteorological drivers (spring minimum temperature and growing season dryness) on observed and simulated inter-annual GPP variations is analysed. Lastly, the impacts of two climate change scenarios on beech GPP are evaluated through statistical analyses of the ground data and model...

  8. A Study on the Quality and Identity of Brazilian Pampa Biome Honey: Evidences for Its Beneficial Effects against Oxidative Stress and Hyperglycemia

    Directory of Open Access Journals (Sweden)

    L. C. Cruz

    2014-01-01

    Full Text Available We characterized, for the first time, the quality and identity of Brazilian Pampa biome honey and its antioxidant properties in vitro (FRAP, DDPH and ABTS. The potential protective effect of honey against oxidative stress induced by iron (Fe and paraquat, (PQ in a Drosophila melanogaster model (in vivo was also tested. The results indicated that all honey samples tested showed antioxidant activity in vitro. Flies treated with honey showed increased lifespan and were protected against oxidative stress induced by Fe and PQ. Despite the high concentration of sugars in honey (approximately 70–80%, our results demonstrate a hypoglycemic-like effect of honey in Drosophila. Thus, this study demonstrates the high quality of Brazilian Pampa biome honey as well as its significant antioxidant activity in vitro and in vivo, pointing to the potential use of this natural product as an alternative in the therapy of oxidative stress-associated diseases.

  9. A Study on the Quality and Identity of Brazilian Pampa Biome Honey: Evidences for Its Beneficial Effects against Oxidative Stress and Hyperglycemia.

    Science.gov (United States)

    Cruz, L C; Batista, J E S; Zemolin, A P P; Nunes, M E M; Lippert, D B; Royes, L F F; Soares, F A; Pereira, A B; Posser, T; Franco, J L

    2014-01-01

    We characterized, for the first time, the quality and identity of Brazilian Pampa biome honey and its antioxidant properties in vitro (FRAP, DDPH and ABTS). The potential protective effect of honey against oxidative stress induced by iron (Fe) and paraquat, (PQ) in a Drosophila melanogaster model (in vivo) was also tested. The results indicated that all honey samples tested showed antioxidant activity in vitro. Flies treated with honey showed increased lifespan and were protected against oxidative stress induced by Fe and PQ. Despite the high concentration of sugars in honey (approximately 70-80%), our results demonstrate a hypoglycemic-like effect of honey in Drosophila. Thus, this study demonstrates the high quality of Brazilian Pampa biome honey as well as its significant antioxidant activity in vitro and in vivo, pointing to the potential use of this natural product as an alternative in the therapy of oxidative stress-associated diseases.

  10. Flux frequency analysis of seasonally dry ecosystem fluxes in two unique biomes of Sonora Mexico

    Science.gov (United States)

    Verduzco, V. S.; Yepez, E. A.; Robles-Morua, A.; Garatuza, J.; Rodriguez, J. C.; Watts, C.

    2013-05-01

    Complex dynamics from the interactions of ecosystems processes makes difficult to model the behavior of ecosystems fluxes of carbon and water in response to the variation of environmental and biological drivers. Although process oriented ecosystem models are critical tools for studying land-atmosphere fluxes, its validity depends on the appropriate parameterization of equations describing temporal and spatial changes of model state variables and their interactions. This constraint often leads to discrepancies between model simulations and observed data that reduce models reliability especially in arid and semiarid ecosystems. In the semiarid north western Mexico, ecosystem processes are fundamentally controlled by the seasonality of water and the intermittence of rain pulses which are conditions that require calibration of specific fitting functions to describe the response of ecosystem variables (i.e. NEE, GPP, ET, respiration) to these wetting and drying periods. The goal is to find functions that describe the magnitude of ecosystem fluxes during individual rain pulses and the seasonality of the ecosystem. Relaying on five years of eddy covariance flux data of a tropical dry forest and a subtropical shrubland we present a flux frequency analysis that describe the variation of net ecosystem exchange (NEE) of CO2 to highlight the relevance of pulse driven dynamics controlling this flux. Preliminary results of flux frequency analysis of NEE indicate that these ecosystems are strongly controlled by the frequency distribution of rain. Also, the output of fitting functions for NEE, GPP, ET and respiration using semi-empirical functions applied at specific rain pulses compared with season-long statistically generated simulations do not agree. Seasonality and the intrinsic nature of individual pulses have different effects on ecosystem flux responses. This suggests that relationships between the nature of seasonality and individual pulses can help improve the

  11. The genetic structure of the mountain forest butterfly Erebia euryale unravels the late Pleistocene and postglacial history of the mountain coniferous forest biome in Europe.

    Science.gov (United States)

    Schmitt, Thomas; Haubrich, Karola

    2008-05-01

    The distribution of the mountain coniferous forest biome in Europe throughout time is not sufficiently understood. One character species of this habitat type is the large ringlet, Erebia euryale well reflecting the extension of this biome today, and the genetic differentiation of this species among and within mountain systems may unravel the late Pleistocene history of this habitat type. We therefore analysed the allozyme pattern of 381 E. euryale individuals from 11 populations in four different European mountain systems (Pyrenees, Alps, Carpathians, Rila). All loci analysed were polymorphic. The mean F(ST) over all samples was high (20%). Furthermore, the mean genetic distance among samples was quite high (0.049). We found four different groups well supported by cluster analyses, bootstraps and hierarchical variance analyses: Pyrenees, western Alps, eastern Alps and southeastern Europe (Carpathians and Rila). The genetic diversity of the populations was highest in the southeastern European group and stepwise decreased westwards. Interestingly, the populations from Bulgaria and Romania were almost identical; therefore, we assume that they were not separated by the Danube Valley, at least during the last ice age. On the contrary, the differentiation among the three western Alps populations was considerable. For all these reasons, we assume that (i) the most important refugial area for the coniferous mountain forest biome in Europe has been located in southeastern Europe including at least parts of the Carpathians and the Bulgarian mountains; (ii) important refugial areas for this biome existed at the southeastern edge of the Alps; (iii) fragments of this habitat types survived along the southwestern Alps, but in a more scattered distribution; and (iv) relatively small relicts have persisted somewhere at the foothills of the Pyrenees.

  12. Testing the applicability of BIOME-BGC to simulate beech gross primary production in Europe using a new continental weather dataset

    OpenAIRE

    Chiesi , Marta; Chirici , Gherardo; Marchetti , Marco; Hasenauer , Hubert; Moreno , Adam; Knohl , Alexander; Matteucci , Giorgio; Pilegaard , Kim; Granier , André; Longdoz , Bernard; Maselli , Fabio

    2016-01-01

    Key message A daily 1-km Pan-European weather dataset can drive the BIOME-BGC model for the estimation of current and future beech gross primary production (GPP). Annual beech GPP is affected primarily by spring temperature and more irregularly by summer water stress. [br/] Context The spread of beech forests in Europe enhances the importance of modelling and monitoring their growth in view of ongoing climate changes. [br/] Aims The current paper assesses the capability o...

  13. Relationships of leaf dark respiration to leaf nitrogen, specific leaf area and leaf life-span: a test across biomes and functional groups.

    Science.gov (United States)

    Reich, Peter B; Walters, Michael B; Ellsworth, David S; Vose, James M; Volin, John C; Gresham, Charles; Bowman, William D

    1998-05-01

    Based on prior evidence of coordinated multiple leaf trait scaling, we hypothesized that variation among species in leaf dark respiration rate (R d ) should scale with variation in traits such as leaf nitrogen (N), leaf life-span, specific leaf area (SLA), and net photosynthetic capacity (A max ). However, it is not known whether such scaling, if it exists, is similar among disparate biomes and plant functional types. We tested this idea by examining the interspecific relationships between R d measured at a standard temperature and leaf life-span, N, SLA and A max for 69 species from four functional groups (forbs, broad-leafed trees and shrubs, and needle-leafed conifers) in six biomes traversing the Americas: alpine tundra/subalpine forest, Colorado; cold temperate forest/grassland, Wisconsin; cool temperate forest, North Carolina; desert/shrubland, New Mexico; subtropical forest, South Carolina; and tropical rain forest, Amazonas, Venezuela. Area-based R d was positively related to area-based leaf N within functional groups and for all species pooled, but not when comparing among species within any site. At all sites, mass-based R d (R d-mass ) decreased sharply with increasing leaf life-span and was positively related to SLA and mass-based A max and leaf N (leaf N mass ). These intra-biome relationships were similar in shape and slope among sites, where in each case we compared species belonging to different plant functional groups. Significant R d-mass -N mass relationships were observed in all functional groups (pooled across sites), but the relationships differed, with higher R d at any given leaf N in functional groups (such as forbs) with higher SLA and shorter leaf life-span. Regardless of biome or functional group, R d-mass was well predicted by all combinations of leaf life-span, N mass and/or SLA (r 2 ≥ 0.79, P morphological, chemical and metabolic traits.

  14. ¿Cómo cambiar hacia sociedades sostenibles? Reflexiones sobre biomímesis y autolimitación

    Directory of Open Access Journals (Sweden)

    Riechmann, Jorge

    2005-06-01

    Full Text Available We live in socio-economical systems which are too large in relation to the biosphere which contains them, on the one hand, and on the other, we live in badly adapted systems, that is, human systems not well fitted into the natural ecosystems. The scale problem calls for a move toward self-limitation by human societies, which (in terms of political economy could be thought of as global demand management; the structural problem demands a reconstruction of the technosphere according to biomimicry principIes.

    Vivimos dentro de sistemas socioeconámicos humanos demasiado grandes en relación con la biosfera que los contiene, por una parte; y sistemas mal adaptados, sistemas humanos que encajan mal en los ecosistemas naturales. El problema de escala reclama un movimiento de autolimitación por parte de las sociedades humanas, que podríamos concebir (en términos de economía política bajo la idea de gestión global de la demanda; el problema de estructura exige una reconstrucción de la tecnosfera de acuerdo con principios de biomímesis.

  15. The contrasting nature of woody plant species in different neotropical forest biomes reflects differences in ecological stability.

    Science.gov (United States)

    Pennington, R Toby; Lavin, Matt

    2016-04-01

    A fundamental premise of this review is that distinctive phylogenetic and biogeographic patterns in clades endemic to different major biomes illuminate the evolutionary process. In seasonally dry tropical forests (SDTFs), phylogenies are geographically structured and multiple individuals representing single species coalesce. This pattern of monophyletic species, coupled with their old species stem ages, is indicative of maintenance of small effective population sizes over evolutionary timescales, which suggests that SDTF is difficult to immigrate into because of persistent resident lineages adapted to a stable, seasonally dry ecology. By contrast, lack of coalescence in conspecific accessions of abundant and often widespread species is more frequent in rain forests and is likely to reflect large effective population sizes maintained over huge areas by effective seed and pollen flow. Species nonmonophyly, young species stem ages and lack of geographical structure in rain forest phylogenies may reflect more widespread disturbance by drought and landscape evolution causing resident mortality that opens up greater opportunities for immigration and speciation. We recommend full species sampling and inclusion of multiple accessions representing individual species in phylogenies to highlight nonmonophyletic species, which we predict will be frequent in rain forest and savanna, and which represent excellent case studies of incipient speciation. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  16. Estimating Trends and Variation of Net Biome Productivity in India for 1980-2012 Using a Land Surface Model

    Science.gov (United States)

    Gahlot, Shilpa; Shu, Shijie; Jain, Atul K.; Baidya Roy, Somnath

    2017-11-01

    In this paper we explore the trend in net biome productivity (NBP) over India for the period 1980-2012 and quantify the impact of different environmental factors, including atmospheric CO2 concentrations ([CO2]), land use and land cover change, climate, and nitrogen deposition on carbon fluxes using a land surface model, Integrated Science Assessment Model. Results show that terrestrial ecosystems of India have been a carbon sink for this period. Driven by a strong CO2 fertilization effect, magnitude of NBP increased from 27.17 TgC/yr in the 1980s to 34.39 TgC/yr in the 1990s but decreased to 23.70 TgC/yr in the 2000s due to change in climate. Adoption of forest conservation, management, and reforestation policies in the past decade has promoted carbon sequestration in the ecosystems, but this effect has been offset by loss of carbon from ecosystems due to rising temperatures and decrease in precipitation.

  17. Understanding the Effect of Land Cover Classification on Model Estimates of Regional Carbon Cycling in the Boreal Forest Biome

    Science.gov (United States)

    Kimball, John; Kang, Sinkyu

    2003-01-01

    The original objectives of this proposed 3-year project were to: 1) quantify the respective contributions of land cover and disturbance (i.e., wild fire) to uncertainty associated with regional carbon source/sink estimates produced by a variety of boreal ecosystem models; 2) identify the model processes responsible for differences in simulated carbon source/sink patterns for the boreal forest; 3) validate model outputs using tower and field- based estimates of NEP and NPP; and 4) recommend/prioritize improvements to boreal ecosystem carbon models, which will better constrain regional source/sink estimates for atmospheric C02. These original objectives were subsequently distilled to fit within the constraints of a 1 -year study. This revised study involved a regional model intercomparison over the BOREAS study region involving Biome-BGC, and TEM (A.D. McGuire, UAF) ecosystem models. The major focus of these revised activities involved quantifying the sensitivity of regional model predictions associated with land cover classification uncertainties. We also evaluated the individual and combined effects of historical fire activity, historical atmospheric CO2 concentrations, and climate change on carbon and water flux simulations within the BOREAS study region.

  18. Estudio biométrico ocular en una población adulta del estado de Sinaloa

    Directory of Open Access Journals (Sweden)

    Juliana Marcela Morales Avalos

    2016-01-01

    Resultados: Se incluyeron 304 ojos con un rango de edad de 29-98 años con una media de 68 años. La distribución por género fue del 53.94% (164 ojos para el género femenino y del 46.05% (140 ojos para el género masculino. El 51.31% (156 ojos fueron derechos y el 48.68% (148 ojos fueron izquierdo. Los resultados de los valores biométricos fueron: profundidad de cámara anterior, rango 2.39-4.6 con promedio de 3.14 mm; espesor de cristalino, rango 2.49-5.42 con promedio de 3.65 mm; profundidad de cámara vítrea, rango de 13.69-19.59 con promedio de 16.28 mm; y la longitud anteroposterior con rango 20.18-27.3 con promedio de 23.09 mm; el promedio del poder dióptrico deseado para emetropía del lente intraocular es de 22.40 dioptrías.

  19. Application of a rule-based model to estimate mercury exchange for three background biomes in the continental United States

    Science.gov (United States)

    Hartman, J.S.; Weisberg, P.J.; Pillai, R.; Ericksen, J.A.; Kuiken, T.; Lindberg, S.E.; Zhang, H.; Rytuba, J.J.; Gustin, M.S.

    2009-01-01

    Ecosystems that have low mercury (Hg) concentrations (i.e., not enriched or impactedbygeologic or anthropogenic processes) cover most of the terrestrial surface area of the earth yet their role as a net source or sink for atmospheric Hg is uncertain. Here we use empirical data to develop a rule-based model implemented within a geographic information system framework to estimate the spatial and temporal patterns of Hg flux for semiarid deserts, grasslands, and deciduous forests representing 45% of the continental United States. This exercise provides an indication of whether these ecosystems are a net source or sink for atmospheric Hg as well as a basis for recommendation of data to collect in future field sampling campaigns. Results indicated that soil alone was a small net source of atmospheric Hg and that emitted Hg could be accounted for based on Hg input by wet deposition. When foliar assimilation and wet deposition are added to the area estimate of soil Hg flux these biomes are a sink for atmospheric Hg. ?? 2009 American Chemical Society.

  20. Woodland expansion in South African grassy biomes based on satellite observations (1990-2013): general patterns and potential drivers.

    Science.gov (United States)

    Skowno, Andrew L; Thompson, Mark W; Hiestermann, Jens; Ripley, Brad; West, Adam G; Bond, William J

    2017-06-01

    Increases in woody plant cover in savanna grassland environments have been reported on globally for over 50 years and are generally perceived as a threat to rangeland productivity and biodiversity. Despite this, few attempts have been made to estimate the extent of woodland increase at a national scale, principally due to technical constraints such as availability of appropriate remote sensing products. In this study, we aimed to measure the extent to which woodlands have replaced grasslands in South Africa's grassy biomes. We use multiseason Landsat data in conjunction with satellite L-band radar backscatter data to estimate the extent of woodlands and grasslands in 1990 and 2013. The method employed allows for a unique, nationwide measurement of transitions between grassland and woodland classes in recent decades. We estimate that during the 23-year study period, woodlands have replaced grasslands over ~57 000 km 2 and conversely that grasslands have replaced woodlands over ~30 000 km 2 , a net increase in the extent of woodland of ~27 000 km 2 and an annual increase of 0.22%. The changes varied markedly across the country; areas receiving over 500 mm mean annual precipitation showed higher rates of woodland expansion than regions receiving 0.19% yr -1 ). The woodland change map presented here provides a unique opportunity to test the numerous models of woody plant encroachment at a national/regional scale. © 2016 John Wiley & Sons Ltd.

  1. Produtividade e características biométricas do capim-braquiária em sistema silvipastoril

    Directory of Open Access Journals (Sweden)

    Cristiam Bosi

    2014-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a produtividade e as características biométricas do capim-braquiária (Urochloa decumbens sob pastejo, em sistema silvipastoril. Avaliou-se um sistema com árvores nativas de interesse comercial, plantadas em renques, no sentido norte-sul, espaçados por 17 m. Utilizou-se o delineamento experimental de blocos ao acaso, com quatro repetições e parcelas subdivididas, tendo-se avaliado o ciclo de rebrota da forragem nas parcelas, e a distância desta em relação aos renques, nas subparcelas. Sete ciclos de rebrota foram avaliados, em quatro distâncias dos renques: a 2 e a 6 m do renque leste, e a 2 e a 6 m do renque oeste. Quantificou-se a produtividade de matéria seca, o índice de área foliar (IAF, a área foliar específica (AFE e a altura das plantas. A produtividade de forragem, nos dois primeiros ciclos, e o IAF, no segundo e no terceiro ciclo, diminuiram com níveis de sombra acima de 39 e 40%, respectivamente. Já a altura de plantas aumentou com sombreamentos superiores a 53%, nos quatro primeiros ciclos; o que também ocorreu com a AFE, com sombreamento superior a 66%, nos três primeiros ciclos.

  2. Explore inhabitants’ perceptions of wildfire and mitigation behaviours in the Cerrado biome, a fire-prone area of Brazil

    Directory of Open Access Journals (Sweden)

    Giovanni Santopuoli

    2017-05-01

    Full Text Available Fire represents an important natural feature of Brazilian landscape, especially in the Cerrado biome. The Cerrado is the economic livelihood of thousands of people from rural areas in Brazil. It is one of the most important hotspot of biodiversity in the world but also it is a fire-prone area thanks to the high flammability index of the vegetation. Residents and native people of this environment use fire very frequently. The majority of wildfires are caused by humans, though there are some aggravating natural factors affecting the risk, intensity and severity of wildfires. Since residents are continuously involved in fire suppression activities, understanding their perceptions is important for the decision makers who must assess the local capacity to preserve natural resources. This study explores perceptions about wildfire risk and fire mitigation behaviors within three municipalities of the state of Tocantins (Brazil. The study demonstrates that survey participants perceived wildfire risk as rather high, although the perceptions were complex and conflicting among interviewees. A wide range of confused perceptions about fire ignition and heterogeneous point of view have carried out form the survey. However, the residence of interviewees and their educational attainment result the variables that significantly (p-value <0.05 affect the inhabitants’ perceptions.

  3. Governing and Delivering a Biome-Wide Restoration Initiative: The Case of Atlantic Forest Restoration Pact in Brazil

    Directory of Open Access Journals (Sweden)

    Severino R. Pinto

    2014-09-01

    Full Text Available In many human-modified tropical landscapes, biodiversity conservation and the provision of ecosystem services require large-scale restoration initiatives. Such initiatives must be able to augment the amount and the quality of remaining natural habitats. There is thus a growing need for long-term, multi-stakeholder and multi-purpose initiatives that result in multiple ecological and socioeconomic benefits at the biome scale. The Atlantic Forest Restoration Pact (AFRP is a coalition of 260+ stakeholders, including governmental agencies, private sector, NGOs and research institutions, aimed at restoring 15 million ha of degraded and deforested lands by 2050. By articulating, and then integrating common interests, this initiative has allowed different sectors of society to implement an ambitious vision and create a forum for public and private concerns regarding forest restoration. The AFRP adopts a set of governance tools so multiple actors can implement key processes to achieve long-term and visionary restoration goals. Having overcome some initial challenges, AFRP now has to incorporate underrepresented stakeholders and enhance its efforts to make forest restoration more economically viable, including cases where restoration could be less expensive and profitable. The AFRP experience has resulted in many lessons learned, which can be shared to foster similar initiatives across tropical regions.

  4. The southern Brazilian grassland biome: soil carbon stocks, fluxes of greenhouse gases and some options for mitigation.

    Science.gov (United States)

    Pillar, V D; Tornquist, C G; Bayer, C

    2012-08-01

    The southern Brazilian grassland biome contains highly diverse natural ecosystems that have been used for centuries for grazing livestock and that also provide other important environmental services. Here we outline the main factors controlling ecosystem processes, review and discuss the available data on soil carbon stocks and greenhouse gases emissions from soils, and suggest opportunities for mitigation of climatic change. The research on carbon and greenhouse gases emissions in these ecosystems is recent and the results are still fragmented. The available data indicate that the southern Brazilian natural grassland ecosystems under adequate management contain important stocks of organic carbon in the soil, and therefore their conservation is relevant for the mitigation of climate change. Furthermore, these ecosystems show a great and rapid loss of soil organic carbon when converted to crops based on conventional tillage practices. However, in the already converted areas there is potential to mitigate greenhouse gas emissions by using cropping systems based on no soil tillage and cover-crops, and the effect is mainly related to the potential of these crop systems to accumulate soil organic carbon in the soil at rates that surpass the increased soil nitrous oxide emissions. Further modelling with these results associated with geographic information systems could generate regional estimates of carbon balance.

  5. Dinámicas TIC en educación biomédica y odontológica

    Directory of Open Access Journals (Sweden)

    Gleyvis Coro Montanet

    2015-12-01

    Full Text Available Ensayo que aborda un espectro de propuestas de nuevas tecnológicas aplicables en el ámbito de la enseñanza biomédica de mayor implicación operatoria, con especificidad en la rama odontológica. Después de un breve repaso de los elementos que han dificultado la inserción de las TIC en las academias médicas, el trabajo ofrece variedad de estrategias para gestionar el cambio y la mejora a través de la aplicación de tecnologías, con apoyo en evidencias de éxito y dependientes de la estrecha relación de lo tecnológico con un modelo educativo -de simulación preclínica y ejercitación teórico/práctica- dinámico y flexible. Todo refrendado por un proyecto de innovación, con base en la investigación-acción, llevado a cabo en la titulación de Odontología de la Universidad Europea de Madrid, que concluye con el aporte de buenas prácticas y una prospectiva de considerable desarrollo a corto y largo plazo. DOI: 10.18870/hlrc.v5i4.290

  6. Caracterización de la superaleación ODS MA 956 para aplicaciones biomédicas

    Directory of Open Access Journals (Sweden)

    Escudero, M. I.

    1998-05-01

    Full Text Available Since the MA 956 was proposed as a possible new biomaterial due to its good corrosion resistance values in physiological fluids a long way, still not finished, has been done. An exhaustive characterization of this alloy at room temperature has been developed. The technological objectives are well established: the possible use of this material for biomedical applications as hip or knee prostheses and as dental implants. The study was performed comparing the results of this alloy with the materials used nowadays as surgical implants, i.e., titanium alloys and polyethylene.

    Desde que la MA 956 fue propuesta como posible nuevo biomaterial en base a su buena resistencia a la corrosión frente a sueros fisiológicos, un largo camino, aún sin finalizar, se ha recorrido, en el que se ha llevado a cabo una caracterización exhaustiva de esta aleación a temperatura ambiente con fines tecnológicos bien definidos: su posible uso en aplicaciones biomédicas, bien sea como prótesis de cadera o de rodilla y para implantes dentales. Los estudios se han llevado a cabo comparando esta aleación con los materiales más comúnmente utilizados en implantes ortopédicos como aleaciones de titanio y polietileno.

  7. Shifts in functional traits elevate risk of fire-driven tree dieback in tropical savanna and forest biomes.

    Science.gov (United States)

    Pellegrini, Adam F A; Franco, Augusto C; Hoffmann, William A

    2016-03-01

    Numerous predictions indicate rising CO2 will accelerate the expansion of forests into savannas. Although encroaching forests can sequester carbon over the short term, increased fires and drought-fire interactions could offset carbon gains, which may be amplified by the shift toward forest plant communities more susceptible to fire-driven dieback. We quantify how bark thickness determines the ability of individual tree species to tolerate fire and subsequently determine the fire sensitivity of ecosystem carbon across 180 plots in savannas and forests throughout the 2.2-million km(2) Cerrado region in Brazil. We find that not accounting for variation in bark thickness across tree species underestimated carbon losses in forests by ~50%, totaling 0.22 PgC across the Cerrado region. The lower bark thicknesses of plant species in forests decreased fire tolerance to such an extent that a third of carbon gains during forest encroachment may be at risk of dieback if burned. These results illustrate that consideration of trait-based differences in fire tolerance is critical for determining the climate-carbon-fire feedback in tropical savanna and forest biomes. © 2015 John Wiley & Sons Ltd.

  8. Design and standardization of PCR primers and protocols for detection of clonal immunoglobulin and T-cell receptor gene recombinations in suspect lymphoproliferations: Report of the BIOMED-2 Concerted Action BMH4-CT98-3936 : Report of the BIOMED-2 Concerted Action BMH4-CT98-3936

    NARCIS (Netherlands)

    van Dongen, J.J.M.; Langerak, A.W.; Bruggemann, M.; Evans, P.A.S.; Hummel, M.; Lavender, F.L.; Delabesse, E.; Davi, F.; Schuuring, E.; Garcia-Sanz, R.; Van Krieken, J.H.J.M.; Droese, J.; Gonzalez, D.; Bastard, C.; White, H.E.; Spaargaren, M.; Gonzalez, M.; Parreira, A.; Smith, J.L.; Morgan, G.J.; Kneba, M.; Macintyre, E.A.

    2003-01-01

    In a European BIOMED-2 collaborative study, multiplex PCR assays have successfully been developed and standardized for the detection of clonally rearranged immunoglobulin (Ig) and T-cell receptor (TCR) genes and the chromosome aberrations t(11; 14) and t(14; 18). This has resulted in 107 different

  9. The relativity of biological function.

    Science.gov (United States)

    Laubichler, Manfred D; Stadler, Peter F; Prohaska, Sonja J; Nowick, Katja

    2015-12-01

    Function is a central concept in biological theories and explanations. Yet discussions about function are often based on a narrow understanding of biological systems and processes, such as idealized molecular systems or simple evolutionary, i.e., selective, dynamics. Conflicting conceptions of function continue to be used in the scientific literature to support certain claims, for instance about the fraction of "functional DNA" in the human genome. Here we argue that all biologically meaningful interpretations of function are necessarily context dependent. This implies that they derive their meaning as well as their range of applicability only within a specific theoretical and measurement context. We use this framework to shed light on the current debate about functional DNA and argue that without considering explicitly the theoretical and measurement contexts all attempts to integrate biological theories are prone to fail.

  10. Structural Biology Fact Sheet

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Structural Biology Structural Biology Tagline (Optional) Middle/Main Content Area PDF Version (688 KB) Other Fact Sheets What is structural biology? Structural biology is the study of how biological ...

  11. First parasitological, histopathological and molecular characterization of Echinococcus vogeli Rausch and Bernstein, 1972 from Cuniculus paca Linnaeus, 1766 in the Cerrado biome (Mato Grosso do Sul, Brazil).

    Science.gov (United States)

    Bittencourt-Oliveira, Fernanda; Teixeira, Paulo; Alencar, Alba; Menezes, Rodrigo; Corrêa, Christiane; Neves, Leandro; Almeida, Fernanda; Daipert-Garcia, Daniel; Machado-Silva, José Roberto; Rodrigues-Silva, Rosângela

    2018-01-30

    Polycystic echinococcosis (PE) is caused by Echinococcus vogeli metacestodes (larval stage) in Neotropical countries. E. vogeli is trophically-transmitted between predators bush dogs (Speothos venaticus) and prey pacas (Cuniculus paca). In Brazil, reported PE cases are restricted to the Amazon biome. In this study, metacestodes from a paca hunted in Mato Grosso do Sul state (Cerrado biome) were identified morphological and histopathological techniques and further confirmed by molecular testing (sequencing of cytochrome C oxidase subunit I (cox1) gene) for the first time. Images of the whole liver showed superficial bubble-like hepatic masses. The parasitological analysis revealed large hooks (41.3 ± 1.2 μm length/12.8 ± 0.8 μm width) and small hooks (33.0 ± 1.5 μm length/11.1 ± 1.2 μm width), consistent with E. vogeli. Microscopically, the liver showed protoscoleces, a thick laminated layer, fibrosis, and inflammatory infiltrate in the adventitial layer. The DNA sequencing confirmed E. vogeli with 99% homology with sequences deposited in the GenBank. In addition, this finding greatly extends the geographic range of animal polycystic echinococcosis into the Cerrado. It is likely to occur in new biomes, where bush dogs and pacas share a given area in a trophic relationship. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Estimating carbon flux phenology with satellite-derived land surface phenology and climate drivers for different biomes: a synthesis of AmeriFlux observations.

    Directory of Open Access Journals (Sweden)

    Wenquan Zhu

    Full Text Available Carbon Flux Phenology (CFP can affect the interannual variation in Net Ecosystem Exchange (NEE of carbon between terrestrial ecosystems and the atmosphere. In this study, we proposed a methodology to estimate CFP metrics with satellite-derived Land Surface Phenology (LSP metrics and climate drivers for 4 biomes (i.e., deciduous broadleaf forest, evergreen needleleaf forest, grasslands and croplands, using 159 site-years of NEE and climate data from 32 AmeriFlux sites and MODIS vegetation index time-series data. LSP metrics combined with optimal climate drivers can explain the variability in Start of Carbon Uptake (SCU by more than 70% and End of Carbon Uptake (ECU by more than 60%. The Root Mean Square Error (RMSE of the estimations was within 8.5 days for both SCU and ECU. The estimation performance for this methodology was primarily dependent on the optimal combination of the LSP retrieval methods, the explanatory climate drivers, the biome types, and the specific CFP metric. This methodology has a potential for allowing extrapolation of CFP metrics for biomes with a distinct and detectable seasonal cycle over large areas, based on synoptic multi-temporal optical satellite data and climate data.

  13. Deep Mapping the Biome: The Biology of Place in Don Gayton's "The Wheatgrass Mechanism" and John Janovy Jr.'s "Dunwoody Pond"

    Science.gov (United States)

    Maher, Susan Naramore

    2005-01-01

    The term "deep map" is the invention of writer William Least Heat-Moon, whose extended essay "PrairyErth (a deep map)" has given definition to this form. Deep-map writing is marked by its intertextual, interdisciplinary, and multivocal nature. It is also self-consciously cartographic, presenting maps, following maps, and redrawing maps. Deep…

  14. [Definition and adoption of a building code based on biological and ecological sustainability in the Local Health Authority 11 of Empoli (Tuscany Region, Central Italy): strengths and areas for improvement].

    Science.gov (United States)

    Petronio, Maria Grazia; Battisti, Francesca

    2016-01-01

    Built environment is an important social determinant of health, but nowadays local health authorities (LHAs) have lost their competences in the issuing of building permits, especially since a new legislation introduced the possibility of personal declaration of conformity. They are also usually excluded from the urban planning process. At the same time, in recent years construction of buildings has been developed with insufficient regard to environmental health requirements, proper exposure to sunlight and winds, comfort, building materials, consumption of resources, and waste production. To deal with these issues, an interdepartmental working group was set up under the direction of the Department of Prevention of the LHA of Empoli (Tuscany Region, Central Italy), with members of the Regional Environmental Protection Agency, along with experts of the 15 Municipalities included in the LHA territory and members of other local institutions. The objective of the Working Group was to define and propose as mandatory a set of rules for local governments aimed at regulating construction activities according to criteria of environmental sustainability, eco-efficiency, comfort, and healthiness of living areas, at the same time encouraging the responsible use of natural resources, the reduction of energy consumption and the use of renewable energy sources in order to place environmental safety and health at the heart of all building activities. Experts of six Municipalities joined the working group and the regulation framework was adopted (and made legally binding) in 8 out of 15 Municipalities, with an almost complete overlap with participation in the working group. The active participation of experts, whose work consists in examining municipal building, permits, and declarations, has therefore marked the difference in the transition from theory to practice. The level of know-how attained by the participants and their motivation and enthusiasm have been so relevant in the

  15. Central Nervous System Vasculitis

    Science.gov (United States)

    ... of Vasculitis / Central Nervous System (CNS) Vasculitis Central Nervous System (CNS) Vasculitis Swap out your current Facebook Profile ... Facebook personal page. Replace with this image. Central nervous system (CNS) vasculitis is inflammation of blood vessel walls ...

  16. Predicting the Dispersal Potential of an Invasive Polychaete Pest along a Complex Coastal Biome.

    Science.gov (United States)

    David, Andrew A; Matthee, Conrad A; Loveday, Benjamin R; Simon, Carol A

    2016-10-01

    Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  17. Biology Branch

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, W F

    1974-12-31

    Progress is reported on the following studies in biochemistry and molecular biology: study of long pyrimidine polynucleotides in DNA; isolation of thymine dimers from Schizosaccharomyces pombe; thermal stability of high molecular weight RNA; nucleases of Micrococcus radiodurans; effect of ionizing radiation on M. radiodurans cell walls and cell membranes; chemical modification of nucleotides; exonucleases of M. radiodurans; and enzymatic basis of repair of radioinduced damage in M. radiodurans. Genetics, development, and population studies include repair pathways and mutation induction in yeast; induction of pure mutant clones in yeast; radiosensitivity of bacteriophage T4; polyacrylamide gel electrophoresis of bacteriophage T4; radiation genetics of Dahibominus; and radiation studies on bitting flies. (HLW)

  18. Modeling the carbon dynamics of the pastures ecosystem in Xinjiang with Biome-BGC model%基于BIOME-BGC模型的新疆牧区生态系统碳动态模拟

    Institute of Scientific and Technical Information of China (English)

    朱士华; 张弛; 李超凡

    2016-01-01

    干旱区生态系统对气候变化的响应复杂而敏感.牧区由于放牧效应的存在以及人为因素的频繁扰动,生态环境极为脆弱,加之实测数据的稀缺,很难对旱地牧区碳动态时空格局形成完整准确的认识.基于修正的Biome-BGC放牧模型,文中评估了新疆牧区1981-2007年间多种情景模式下的碳动态格局.结果表明:新疆牧区总体上表现为碳汇,27年间共固持59Tg(1Tg=1012g)C,其中VEGC(植被碳)和SOC(土壤碳)占比相当,分别占总固持量的43.04%、43.08%;放牧导致20.58Tg C的流失,而CO2施肥效应则导致了64.29TgC的固定,气候变化导致的碳失汇量为9.52Tg.80年代中期牧区VEGC存在显著下降过程,可能与这段时期的持续干旱有关,但SOC受此影响较小,研究描绘了旱地碳动态时空格局,为后续研究提供数据支持.

  19. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  20. "Heart-cut" bidimensional achiral-chiral liquid chromatography applied to the evaluation of stereoselective metabolism, in vivo biological activity and brain response to chiral drug candidates targeting the central nervous system.

    Science.gov (United States)

    Battisti, Umberto M; Citti, Cinzia; Larini, Martina; Ciccarella, Giuseppe; Stasiak, Natalia; Troisi, Luigino; Braghiroli, Daniela; Parenti, Carlo; Zoli, Michele; Cannazza, Giuseppe

    2016-04-22

    A "heart-cut" two-dimensional achiral-chiral liquid chromatography triple-quadrupole mass spectrometry method (LC-LC-MS/MS) was developed and coupled to in vivo cerebral microdialysis to evaluate the brain response to the chiral compound (±)-7-chloro-5-(3-furanyl)-3-methyl-3,4-dihydro-2H-1,2,4-benzothiadiazine-1,1-dioxide ((±)-1), a potent positive allosteric modulator (PAM) of AMPA receptor. The method was successfully employed to evaluate also its stereoselective metabolism and in vitro biological activity. In particular, the LC achiral method developed, employs a pentafluorinated silica based column (Discovery HS-F5) to separate dopamine, acetylcholine, serotonin, (±)-1 and its two hepatic metabolites. In the "heart-cut" two-dimension achiral-chiral configuration, (±)-1 and (±)-1-d4 eluted from the achiral column (1st dimension), were transferred to a polysaccharide-based chiral column (2nd dimension, Chiralcel OD-RH) by using an automatic six-port valve. Single enantiomers of (±)-1 were separated and detected using electrospray positive ionization mode and quantified in selected reaction monitoring mode. The method was validated and showed good performance in terms of linearity, accuracy and precision. The new method employed showed several possible applications in the evaluation of: (a) brain response to neuroactive compounds by measuring variations in the brain extracellular levels of selected neurotransmitters and other biomarkers; (b) blood brain barrier penetration of drug candidates by measuring the free concentration of the drug in selected brain areas; (c) the presence of drug metabolites in the brain extracellular fluid that could prove very useful during drug discovery; (d) a possible stereoselective metabolization or blood brain barrier stereoselective crossing of chiral drugs. Finally, compared to the methods reported in the literature, this technique avoids the necessity of euthanizing an animal at each time point to measure drug