932 resultados para BIOLOGICAL DIVERSITY


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Stabilizing human population size and reducing human-caused impacts on the environment are keys to conserving threatened species (TS). Earth's human population is ~ 7 billion and increasing by ~ 76 million per year. This equates to a human birth-death ratio of 2.35 annually. The 2007 Red List prepared by the International Union for Conservation of Nature and Natural Resources (IUCN) categorized 16,306 species of vertebrates, invertebrates, plants, and other organisms (e.g., lichens, algae) as TS. This is ~ 1 percent of the 1,589,161 species described by IUCN or ~ 0.0033 percent of the believed 5,000,000 total species. Of the IUCN’s described species, vertebrates comprised relatively the most TS listings within respective taxonomic categories (5,742 of 59,811), while invertebrates (2,108 of 1,203,175), plants (8,447 of 297,326), and other species (9 of 28,849) accounted for minor class percentages. Conservation economics comprises microeconomic and macroeconomic principles involving interactions among ecological, environmental, and natural resource economics. A sustainable-growth (steady-state) economy has been posited as instrumental to preserving biological diversity and slowing extinctions in the wild, but few nations endorse this approach. Expanding growth principles characterize most nations' economic policies. To date, statutory fine, captive breeding cost, contingent valuation analysis, hedonic pricing, and travel cost methods are used to value TS in economic research and models. Improved valuation methods of TS are needed for benefit-cost analysis (BCA) of conservation plans. This Chapter provides a review and analysis of: (1) the IUCN status of species, (2) economic principles inherent to sustainable versus growth economies, and (3) methodological issues which hinder effective BCAs of TS conservation.

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A comprehensive new inventory of Brazilian plants and fungi was published just in time to meet a 2010 Convention on Biological Diversity target and offers important insights into this biodiversity's global significance. Brazil is the home to the world's richest flora (40,989 species; 18,932 endemic) and includes two of the hottest hotspots: Mata Atlantica (19,355 species) and Cerrado (12,669 species). Although the total number of known species is one-third lower than previous estimates, the absolute number of endemic vascular plant species is higher than was previously estimated, and the proportion of endemism (56%) is the highest in the Neotropics. This compilation serves not merely to quantify the scale of the challenge faced in conserving Brazil's unique flora but also serves as a key resource to direct action and monitor progress. Similar efforts by other megadiverse countries are urgently required if the 2020 targets of the Convention on Biological Diversity and the Global Strategy for Plant Conservation are to be attained.

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The Laje de Santos Marine State Park (LSMSP), located in southeastern Brazil, is the only marine park in Sao Paulo State. This conservation unit has been established as a protected area of high biological diversity. Despite its importance for the conservation of the marine biota, little is known about the park's seaweed flora. The objectives of this study were as follows: to furnish increased knowledge of the composition of the macroalgae in the Park area; to relate the area's macroalgal composition to the presence of an important water mass in the region, the South Atlantic Central Water (SACW); and to investigate the possible influence of the Port of Santos on the composition of the macroalgae of the LSMSP. This study registered 31 new records for the LSMSP, 11 for Sao Paulo State, four for Brazil, one for the western Atlantic and one for the South Atlantic Ocean, in addition to the possible occurrence of one new species of Osmundea (Rhodomelaceae) and one new genus belonging to Ceramiaceae. The taxonomic composition of the macroalgae had a direct correlation with the arrival of the SACW in the summer-fall season. The SACW generated a strong thermocline and increased the supply of nutrients in the water column. Hydrodynamic and dispersion modeling analyses suggested that the Port of Santos influenced the composition of the LSMSP phycoflora.

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The time is ripe for a comprehensive mission to explore and document Earth's species. This calls for a campaign to educate and inspire the next generation of professional and citizen species explorers, investments in cyber-infrastructure and collections to meet the unique needs of the producers and consumers of taxonomic information, and the formation and coordination of a multi-institutional, international, transdisciplinary community of researchers, scholars and engineers with the shared objective of creating a comprehensive inventory of species and detailed map of the biosphere. We conclude that an ambitious goal to describe 10 million species in less than 50 years is attainable based on the strength of 250 years of progress, worldwide collections, existing experts, technological innovation and collaborative teamwork. Existing digitization projects are overcoming obstacles of the past, facilitating collaboration and mobilizing literature, data, images and specimens through cyber technologies. Charting the biosphere is enormously complex, yet necessary expertise can be found through partnerships with engineers, information scientists, sociologists, ecologists, climate scientists, conservation biologists, industrial project managers and taxon specialists, from agrostologists to zoophytologists. Benefits to society of the proposed mission would be profound, immediate and enduring, from detection of early responses of flora and fauna to climate change to opening access to evolutionary designs for solutions to countless practical problems. The impacts on the biodiversity, environmental and evolutionary sciences would be transformative, from ecosystem models calibrated in detail to comprehensive understanding of the origin and evolution of life over its 3.8 billion year history. The resultant cyber-enabled taxonomy, or cybertaxonomy, would open access to biodiversity data to developing nations, assure access to reliable data about species, and change how scientists and citizens alike access, use and think about biological diversity information.

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The aim of this study was to evaluate the use of new oligonucleotide primers (mcyB-F/R, mcyB-F/R-A, and mcyB-F/R-B) designed from Brazilian cyanobacteria for the detection of microcystin-producing genotypes in 27 environmental samples from water reservoirs and 11 strains of Microcystis. Microcystins were found using HPLC in all 11 strains and 19 of the environmental samples. The new oligonucleotide primers amplified fragments of microcystin-producing genes, including the eight environmental samples in which no microcystins were detected by HPLC, but which presented amplified fragments, thereby demonstrating the existence of microcystin-producing genes. The new oligonucleotide primers exhibited better specificity when used with environmental samples and were more reliable in comparison with those described in the literature (mcyB-FAA/RAA and mcyA-Cd/FR), which generate false-negative results. The better performance of these new oligonucleotide primers underline the need for designing molecular markers that are well fitted to the regional biological diversity. As this is a fast predictive technique for determining the presence or absence of microcystins, it could be used either alone or in conjunction with other techniques, such as the screening of samples to be sent for quantitative toxicological analysis using HPLC, thereby reducing monitoring cost and time. (c) 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.

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The 1992 Rio Earth Summit was of paramount importance in the consolidation and international dissemination of environmental impact assessment, officially recognized as a tool for informed decision-making towards sustainable development (Principle 17, Rio Declaration) and for protection of biodiversity (Article 14, Convention on Biological Diversity). A significant development afterwards was the strengthening of strategic environmental assessment in the design of policies, plans and programs. Both forms of impact assessment can establish the necessary connections between one goal of the Rio+20 Conference - reaching an agreement on the transition to a green economy - and the underpinning decision making processes. Although the Rio+20 Summit has faced challenges to acknowledge its potential, impact assessment should be strengthened in support of both government and business decisions.

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The Laje de Santos Marine State Park (LSMSP), located in southeastern Brazil, is the only marine park in São Paulo State. This conservation unit has been established as a protected area of high biological diversity. Despite its importance for the conservation of the marine biota, little is known about the park's seaweed flora. The objectives of this study were as follows: to furnish increased knowledge of the composition of the macroalgae in the Park area; to relate the area's macroalgal composition to the presence of an important water mass in the region, the South Atlantic Central Water (SACW); and to investigate the possible influence of the Port of Santos on the composition of the macroalgae of the LSMSP. This study registered 31 new records for the LSMSP, 11 for São Paulo State, four for Brazil, one for the western Atlantic and one for the South Atlantic Ocean, in addition to the possible occurrence of one new species of Osmundea (Rhodomelaceae) and one new genus belonging to Ceramiaceae. The taxonomic composition of the macroalgae had a direct correlation with the arrival of the SACW in the summer-fall season. The SACW generated a strong thermocline and increased the supply of nutrients in the water column. Hydrodynamic and dispersion modeling analyses suggested that the Port of Santos influenced the composition of the LSMSP phycoflora.

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Several coralligenous reefs occur in the soft bottoms of the northern Adriatic continental shelf. Mediterranean coralligenous habitats are characterised by high species diversity and are intrinsically valuable for their biological diversity and for the ecological processes they support. The conservation and management of these habitats require quantifying spatial and temporal variability of their benthic assemblages. This PhD thesis aims to give a relevant contribution to the knowledge of the structure and dynamics of the epibenthic assemblages on the coralligenous subtidal reefs occurring in the northern Adriatic Sea. The epibenthic assemblages showed a spatial variation larger compared to temporal changes, with a temporal persistence of reef-forming organisms. Assemblages spatial heterogeneity has been related to morphological features and geographical location of the reefs, together with variation in the hydrological conditions. Manipulative experiments help to understand the ecological processes structuring the benthic assemblages and maintaining their diversity. In this regards a short and long term experiment on colonization patterns of artificial substrata over a 3-year period has been performed in three reefs, corresponding to the three main types of assemblages detected in the previous study. The first colonisers, largely depending by the different larval supply, played a key role in determining the heterogeneity of the assemblages in the early stage of colonisation. Lateral invasion, from the surrounding assemblages, was the driver in structuring the mature assemblages. These complex colonisation dynamics explained the high heterogeneity of the assemblages dwelling on the northern Adriatic biogenic reefs. The buildup of these coralligenous reefs mainly depends by the bioconstruction-erosion processes that has been analysed through a field experiment. Bioconstruction, largely due to serpulid polychaetes, prevailed on erosion processes and occurred at similar rates in all sites. Similarly, the total energy contents in the benthic communities do not differ among sites, despite being provided by different species. Therefore, we can hypothesise that both bioconstruction processes and energetic storage may be limited by the availability of resources. Finally the major contribution of the zoobenthos compared to the phytobenthos to the total energetic content of assemblages suggests that the energy flow in these benthic habitats is primarily supported by planktonic food web trough the filter feeding invertebrates.

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Successful conservation of tropical montane forest, one of the most threatened ecosystems on earth, requires detailed knowledge of its biogeochemistry. Of particular interest is the response of the biogeochemical element cycles to external influences such as element deposition or climate change. Therefore the overall objective of my study was to contribute to improved understanding of role and functioning of the Andean tropical montane forest. In detail, my objectives were to determine (1) the role of long-range transported aerosols and their transport mechanisms, and (2) the role of short-term extreme climatic events for the element budget of Andean tropical forest. In a whole-catchment approach including three 8-13 ha microcatchments under tropical montane forest on the east-exposed slope of the eastern cordillera in the south Ecuadorian Andes at 1850-2200 m above sea level I monitored at least in weekly resolution the concentrations and fluxes of Ca, Mg, Na, K, NO3-N, NH4-N, DON, P, S, TOC, Mn, and Al in bulk deposition, throughfall, litter leachate, soil solution at the 0.15 and 0.3 m depths, and runoff between May 1998 and April 2003. I also used meteorological data from my study area collected by cooperating researchers and the Brazilian meteorological service (INPE), as well as remote sensing products of the North American and European space agencies NASA and ESA. My results show that (1) there was a strong interannual variation in deposition of Ca [4.4-29 kg ha-1 a-1], Mg [1.6-12], and K [9.8-30]) between 1998 and 2003. High deposition changed the Ca and Mg budgets of the catchments from loss to retention, suggesting that the additionally available Ca and Mg was used by the ecosystem. Increased base metal deposition was related to dust outbursts of the Sahara and an Amazonian precipitation pattern with trans-regional dry spells allowing for dust transport to the Andes. The increased base metal deposition coincided with a strong La Niña event in 1999/2000. There were also significantly elevated H+, N, and Mn depositions during the annual biomass burning period in the Amazon basin. Elevated H+ deposition during the biomass burning period caused elevated base metal loss from the canopy and the organic horizon and deteriorated already low base metal supply of the vegetation. Nitrogen was only retained during biomass burning but not during non-fire conditions when deposition was much smaller. Therefore biomass burning-related aerosol emissions in Amazonia seem large enough to substantially increase element deposition at the western rim of Amazonia. Particularly the related increase of acid deposition impoverishes already base-metal scarce ecosystems. As biomass burning is most intense during El Niño situations, a shortened ENSO cycle because of global warming likely enhances the acid deposition at my study forest. (2) Storm events causing near-surface water flow through C- and nutrient-rich topsoil during rainstorms were the major export pathway for C, N, Al, and Mn (contributing >50% to the total export of these elements). Near-surface flow also accounted for one third of total base metal export. This demonstrates that storm-event related near-surface flow markedly affects the cycling of many nutrients in steep tropical montane forests. Changes in the rainfall regime possibly associated with global climate change will therefore also change element export from the study forest. Element budgets of Andean tropical montane rain forest proved to be markedly affected by long-range transport of Saharan dust, biomass burning-related aerosols, or strong rainfalls during storm events. Thus, increased acid and nutrient deposition and the global climate change probably drive the tropical montane forest to another state with unknown consequences for its functions and biological diversity.

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The aim of this dissertation is to propose the translation of four chapters from "The invisible history of the human race", an essay by the Australian author and journalist Christine Kenneally. This essay offers a non-systematic overview upon genealogy in connection to the idea of personal identity; above all, the author wants to persuade the reader that genealogy could be the perfect linking point between history and science, family lines and DNA. The translated chapters particularly concentrate on the reasons of the current underestimation of genealogy, which, according to Kenneally, lies in the Nazi’s distorted use of ancestry and in the exploitation of the idea of biological diversity in order to discriminate people. The dissertation is composed of four chapters. The first chapter consists in a concise analysis of the characteristics of the textual genre and in a theoretical introduction and approach to the translation of essays, where the main generic and essay-specific translation strategies are outlined. The second chapter presents a detailed illustration of the topics treated in the essay and particularly in the translated pages. The third chapter contains the translation and the fourth presents a systematic comment to the translation and to the choices made during the translation of the text.

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Biological diversity and its constituent chemical diversity have served as one of the richest sources of bioprospecting leading to the discovery of some of the most important bioactive molecules for mankind. Despite this excellent record, in the recent past, however, bioprospecting of biological resources has met with little success; there has been a perceptible decline in the discovery of novel bioactive compounds. Several arguments have been proposed to explain the current poor success in bioprospecting. Among them, it has been argued that to bioprospect more biodiversity may not necessarily be productive, considering that chemical and functional diversity might not scale with biological diversity. In this paper, we offer a critique on the current perception of biodiversity and chemodiversity and ask to what extent it is relevant in the context of bioprospecting. First, using simple models, we analyze the relation among biodiversity, chemodiversity and functional redundancies in chemical plans of plants and argue that the biological space for exploration might still be wide open. Second, in the context of future bioprospecting, we argue that brute-force high throughput screening approaches alone are insufficient and cost ineffective in realizing bioprospecting success. Therefore, intelligent or non-random approaches to bioprospecting need to be adopted. We review here few examples of such approaches and show how these could be further developed and used in the future to accelerate the pace of discovery.

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Background Meadows are regularly mown in order to provide fodder or litter for livestock and to prevent vegetation succession. However, the time of year at which meadows should be first mown in order to maximize biological diversity remains controversial and may vary with respect to context and focal taxa. We carried out a systematic review and meta-analysis on the effects of delaying the first mowing date upon plants and invertebrates in European meadowlands. Methods Following a CEE protocol, ISI Web of Science, Science Direct, JSTOR, Google and Google Scholar were searched. We recorded all studies that compared the species richness of plants, or the species richness or abundance of invertebrates, between grassland plots mown at a postponed date (treatment) vs plots mown earlier (control). In order to be included in the meta-analysis, compared plots had to be similar in all management respects, except the date of the first cut that was (mostly experimentally) manipulated. They were also to be located in the same meadow type. Meta-analyses applying Hedges’d statistic were performed. Results Plant species richness responded differently to the date to which mowing was postponed. Delaying mowing from spring to summer had a positive effect, while delaying either from spring to fall, or from early summer to later in the season had a negative effect. Invertebrates were expected to show a strong response to delayed mowing due to their dependence on sward structure, but only species richness showed a clearly significant positive response. Invertebrate abundance was positively influenced in only a few studies. Conclusions The present meta-analysis shows that in general delaying the first mowing date in European meadowlands has either positive or neutral effects on plant and invertebrate biodiversity (except for plant species richness when delaying from spring to fall or from early summer to later). Overall, there was also strong between-study heterogeneity, pointing to other major confounding factors, the elucidation of which requires further field experiments with both larger sample sizes and a distinction between taxon-specific and meadow-type-specific responses.

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An interdisciplinary research unit consisting of 30 teams in the natural, economic and social sciences analyzed biodiversity and ecosystem services of a mountain rainforest ecosystem in the hotspot of the tropical Andes, with special reference to past, current and future environmental changes. The group assessed ecosystem services using data from ecological field and scenario-driven model experiments, and with the help of comparative field surveys of the natural forest and its anthropogenic replacement system for agriculture. The book offers insights into the impacts of environmental change on various service categories mentioned in the Millennium Ecosystem Assessment (2005): cultural, regulating, supporting and provisioning ecosystem services. Examples focus on biodiversity of plants and animals including trophic networks, and abiotic/biotic parameters such as soils, regional climate, water, nutrient and sediment cycles. The types of threats considered include land use and climate changes, as well as atmospheric fertilization. In terms of regulating and provisioning services, the emphasis is primarily on water regulation and supply as well as climate regulation and carbon sequestration. With regard to provisioning services, the synthesis of the book provides science-based recommendations for a sustainable land use portfolio including several options such as forestry, pasture management and the practices of indigenous peoples. In closing, the authors show how they integrated the local society by pursuing capacity building in compliance with the CBD-ABS (Convention on Biological Diversity - Access and Benefit Sharing), in the form of education and knowledge transfer for application.

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Whether interspecific hybridization is important as a mechanism that generates biological diversity is a matter of controversy. Whereas some authors focus on the potential of hybridization as a source of genetic variation, functional novelty and new species, others argue against any important role, because reduced fitness would typically render hybrids an evolutionary dead end. By drawing on recent developments in the genetics and ecology of hybridization and on principles of ecological speciation theory, I develop a concept that reconciles these views and adds a new twist to this debate. Because hybridization is common when populations invade new environments and potentially elevates rates of response to selection, it predisposes colonizing populations to rapid adaptive diversification under disruptive or divergent selection. I discuss predictions and suggest tests of this hybrid swarm theory of adaptive radiation and review published molecular phylogenies of adaptive radiations in light of the theory. Some of the confusion about the role of hybridization in evolutionary diversification stems from the contradiction between a perceived necessity for cessation of gene flow to enable adaptive population differentiation on the one hand [1], and the potential of hybridization for generating adaptive variation, functional novelty and new species 2, 3 and 4 on the other. Much progress in the genetics 5, 6, 7, 8 and 9 and ecology of hybridization 9, 10 and 11, and in our understanding of the role of ecology in speciation (see Glossary) 12, 13 and 14 make a re-evaluation timely. Whereas botanists traditionally stressed the diversity-generating potential of hybridization 2, 3 and 14, zoologists traditionally saw it as a process that limits diversification [1] and refer to it mainly in the contexts of hybrid zones (Box 1) and reinforcement of reproductive isolation [15]. Judging by the wide distribution of allopolyploidy among plants, many plant species might be of direct hybrid origin or descended from a hybrid species in the recent past [16]. The ability to reproduce asexually might explain why allopolyploid hybrid species are more common in plants than in animals. Allopolyploidy arises when meiotic mismatch of parental chromosomes or karyotypes causes hybrid sterility. Mitotic error, duplicating the karyotype, can restore an asexually maintained hybrid line to fertility. Although bisexual allopolyploid hybrid species are not uncommon in fish [17] and frogs [18], the difficulty with which allopolyploid animals reproduce, typically requiring gynogenesis[19], makes establishment and survival of allopolyploid animal species difficult.

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This study aims to evaluate the potential for impacts of ocean acidification on North Atlantic deep-sea ecosystems in response to IPCC AR5 Representative Concentration Pathways (RCPs). Deep-sea biota is likely highly vulnerable to changes in seawater chemistry and sensitive to moderate excursions in pH. Here we show, from seven fully coupled Earth system models, that for three out of four RCPs over 17% of the seafloor area below 500 m depth in the North Atlantic sector will experience pH reductions exceeding −0.2 units by 2100. Increased stratification in response to climate change partially alleviates the impact of ocean acidification on deep benthic environments. We report on major pH reductions over the deep North Atlantic seafloor (depth >500 m) and at important deep-sea features, such as seamounts and canyons. By 2100, and under the high CO2 scenario RCP8.5, pH reductions exceeding −0.2 (−0.3) units are projected in close to 23% (~15%) of North Atlantic deep-sea canyons and ~8% (3%) of seamounts – including seamounts proposed as sites of marine protected areas. The spatial pattern of impacts reflects the depth of the pH perturbation and does not scale linearly with atmospheric CO2 concentration. Impacts may cause negative changes of the same magnitude or exceeding the current target of 10% of preservation of marine biomes set by the convention on biological diversity, implying that ocean acidification may offset benefits from conservation/management strategies relying on the regulation of resource exploitation.