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1.
Sci Total Environ ; 938: 173192, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761951

RESUMO

Anthropogenic pressure in areas of biodiversity importance erodes the integrity of the ecosystems they harbour, making features of biodiversity less buffered against extreme climatic events. We define the combination of these disturbances as compound events. We assessed compound event risk in protected areas (PAs) applying a spatial framework guided by criteria and quantitative thresholds associated with exposure to cyclones, drought, and intense human pressure. This assessment was used in a relational matrix to classify PAs with different risk of compound event occurrence. We identified PAs of higher conservation concern by quantifying the extent of human pressure in their surrounding landscape while harbouring large numbers of threatened vertebrate species. Of the 39,694 PAs assessed, very high risk of compound events was determined for 6965 PAs (17.5 %) related to cyclones and human pressure (mainly island hotspots), 6367 PAs (16 %) related to droughts and human pressure (island and continental hotspots), and 2031 PAs (5 %) to cyclones, drought and human pressure (mainly in island hotspots). From the subset of 2031 PAs assessed at very high risk, we identified 239 PAs of higher conservation concern distributed predominantly in the Caribbean Islands, Japan, North America Coastal Plain, Philippines, and Southwest Australia. Our work highlights PAs in the biodiversity hotspots where high risk of compound event occurrence poses a greater threat to species. We encourage researchers to adapt and apply this framework across other globally significant sites for conserving biodiversity to identify high risk-prone areas, and prevent further biodiversity decline.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Conservação dos Recursos Naturais/métodos , Humanos , Secas , Mudança Climática , Ecossistema , Animais , Clima
3.
Nat Commun ; 11(1): 5978, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33293507

RESUMO

Many global environmental agendas, including halting biodiversity loss, reversing land degradation, and limiting climate change, depend upon retaining forests with high ecological integrity, yet the scale and degree of forest modification remain poorly quantified and mapped. By integrating data on observed and inferred human pressures and an index of lost connectivity, we generate a globally consistent, continuous index of forest condition as determined by the degree of anthropogenic modification. Globally, only 17.4 million km2 of forest (40.5%) has high landscape-level integrity (mostly found in Canada, Russia, the Amazon, Central Africa, and New Guinea) and only 27% of this area is found in nationally designated protected areas. Of the forest inside protected areas, only 56% has high landscape-level integrity. Ambitious policies that prioritize the retention of forest integrity, especially in the most intact areas, are now urgently needed alongside current efforts aimed at halting deforestation and restoring the integrity of forests globally.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/estatística & dados numéricos , Política Ambiental , Florestas , África Central , Canadá , Mudança Climática , Conservação dos Recursos Naturais/legislação & jurisprudência , Nova Guiné , Federação Russa
4.
Biosens Bioelectron ; 84: 7-14, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27140308

RESUMO

In the fields of clinical diagnostics and point-of-care diagnosis as well as food and environmental monitoring there is a high demand for reliable high-throughput, rapid and highly sensitive assays for a simultaneous detection of several analytes in complex and low-volume samples. Sensor platforms based on solution-processable electrolyte-gated carbon nanotube field-effect transistors (CNT-FETs) are a simple and cost-effective alternative for conventional assays. In this work we demonstrate a selective as well as direct detection of the products of an enzyme-substrate interaction, here the for metabolic processes important urea-urease system, with sensors based on spray-coated CNT-FETs. The selective and direct detection is achieved by immobilizing the enzyme urease via certain surface functionalization techniques on the sensor surface and further modifying the active interfaces with polymeric ion-selective membranes as well as pH-sensitive layers. Thereby, we can avoid the generally applied approach for a field-effect based detection of enzyme reactions via detecting changes in the pH value due to an on-going enzymatic reaction and directly detect selectively the products of the enzymatic conversion. Thus, we can realize a buffering-capacity independent monitoring of changes in the substrate concentration.


Assuntos
Técnicas Biossensoriais/instrumentação , Ensaios Enzimáticos/instrumentação , Enzimas Imobilizadas/metabolismo , Nanotubos de Carbono/química , Transistores Eletrônicos , Ureia/metabolismo , Urease/metabolismo , Enzimas Imobilizadas/química , Desenho de Equipamento , Humanos , Ureia/análise , Urease/química
7.
Science ; 313(5783): 58-61, 2006 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-16825561

RESUMO

The location of and threats to biodiversity are distributed unevenly, so prioritization is essential to minimize biodiversity loss. To address this need, biodiversity conservation organizations have proposed nine templates of global priorities over the past decade. Here, we review the concepts, methods, results, impacts, and challenges of these prioritizations of conservation practice within the theoretical irreplaceability/vulnerability framework of systematic conservation planning. Most of the templates prioritize highly irreplaceable regions; some are reactive (prioritizing high vulnerability), and others are proactive (prioritizing low vulnerability). We hope this synthesis improves understanding of these prioritization approaches and that it results in more efficient allocation of geographically flexible conservation funding.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Animais , Conservação dos Recursos Naturais/economia , Meio Ambiente , Apoio Financeiro , Geografia , Humanos , Invertebrados , Mamíferos , Plantas , Densidade Demográfica , Vertebrados
8.
Proc Natl Acad Sci U S A ; 100(18): 10309-13, 2003 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-12930898

RESUMO

Human pressure threatens many species and ecosystems, so conservation efforts necessarily prioritize saving them. However, conservation should clearly be proactive wherever possible. In this article, we assess the biodiversity conservation value, and specifically the irreplaceability in terms of species endemism, of those of the planet's ecosystems that remain intact. We find that 24 wilderness areas, all > or = 1 million hectares, are > or = 70% intact and have human densities of less than or equal to five people per km2. This wilderness covers 44% of all land but is inhabited by only 3% of people. Given this sparse population, wilderness conservation is cost-effective, especially if ecosystem service value is incorporated. Soberingly, however, most wilderness is not speciose: only 18% of plants and 10% of terrestrial vertebrates are endemic to individual wildernesses, the majority restricted to Amazonia, Congo, New Guinea, the Miombo-Mopane woodlands, and the North American deserts. Global conservation strategy must target these five wildernesses while continuing to prioritize threatened biodiversity hotspots.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Humanos
11.
Nature ; 403(6772): 853-8, 2000 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-10706275

RESUMO

Conservationists are far from able to assist all species under threat, if only for lack of funding. This places a premium on priorities: how can we support the most species at the least cost? One way is to identify 'biodiversity hotspots' where exceptional concentrations of endemic species are undergoing exceptional loss of habitat. As many as 44% of all species of vascular plants and 35% of all species in four vertebrate groups are confined to 25 hotspots comprising only 1.4% of the land surface of the Earth. This opens the way for a 'silver bullet' strategy on the part of conservation planners, focusing on these hotspots in proportion to their share of the world's species at risk.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Plantas , Apoio à Pesquisa como Assunto
13.
People Planet ; 7(4): 10-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-12348874

RESUMO

PIP: US-based Conservation International has completed an updated version of its Global Biodiversity Hotspots map. This map shows areas of key importance in the battle to save the planet's diversity of life. In this article, an explanation of what the map reveals and how it can be used to develop a global conservation strategy is presented. Focusing on the terrestrial realm, analysis identified regions with 0.5% or more of total global plant diversity represented as endemic species and tropical rainforest hotspots generally having a very high vertebrate diversity and endemism. The first 25 high-priority terrestrial biodiversity hotspots included tropical rainforest areas, tropical dry forest, arid systems, temperate Mediterranean-type ecosystems, savannas, and steppes as well as combinations of these areas. Among these 25 biodiversity spots, top-priority spots have been specified since total diversity in such areas is much higher than what is represented by the endemic alone. Focusing conservation efforts on these areas can achieve maximum impact on the preservation of the Earth's environment.^ieng


Assuntos
Ecossistema , Meio Ambiente
14.
Folia Primatol (Basel) ; 36(1-2): 1-39, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6802728

RESUMO

The eight monkey species occurring in Surinam were studied in the Raleigh-vallen-Voltzberg Nature Reserve along the Coppename River. Special emphasis was placed on determining how these eight species divide up available habitat and food resources within a 300-ha study area. Cebus apella apella is probably the most adaptable of the Surinam monkeys. It was found mainly in the understory and lower to middle parts of the canopy of all five forest types (high rain forest, low rain forest, mountain savanna forest, liane forest, pina swamp forest) in the study area, and entered a variety of edge habitats. Saguinus midas midas, the only callitrichid in Surinam, also occurred mainly in the understory and lower to middle parts of the canopy of all five forest types, but was the only species to spend more time in edges than in non-edge habitats. Alouatta seniculus was most often seen in the middle to upper strata of high forest, but occasionally entered the four other forest types and a variety of edges. Cebus nigrivittatus is apparently less adaptable than its congener and was largely restricted to the understory and lower to middle strata of high forest. It occasionally entered two other forest types as well, but was rarely seen in edges. Chiropotes and Pithecia were both found almost exclusively in high forest and mountain savanna forest, but Chiropotes was mainly in the upper part of the canopy and in emergents, whereas Pithecia occupied the lower to middle parts of the canopy and the understory. Neither species made much use of edges. Ateles paniscus paniscus and Saimiri sciureus represent the extremes of primate adaptation in the Voltzberg area. Ateles was the most restricted species, and was found almost exclusively in high forest. It very rarely entered edges and was most often seen in the uppermost forest strata. In contrast, Saimiri was the only species that was not found most often in high forest, and it occurred consistently lower than any other monkey in the area. More than 50% of all Saimiri observations were in liane forest, a habitat rarely or never entered by most of the other species, and more than 60% were in the understory stratum. Saguinus, Saimiri, Cebus apella and C. nigrivittatus were omnivorous, with Saimiri apparently eating the most arthropods. The four remaining species were not seen feeding on insects or other animals. All eight species included a high proportion of fruit in their diet, with flowers and sometimes leaves usually playing a minor role. The two largest species, Alouatta and Ateles, were the most folivorous, but Alouatta was the only one that ate mature leaves and its leaf intake far exceeded that of Ateles. The three smallest species (Saguinus, Saimiri, Pithecia) did not eat leaves at all. Chiropotes was an important seed predator; Pithecia and C. Nigrivittatus may also depend heavily on seeds. Alouatta and Saimiri were never seen acting as seed predators. Alouatta and Ateles were major seed dispersers. The other six species occasionally dispersed seeds, but to a much lesser extent.


Assuntos
Dieta , Haplorrinos , Alouatta , Animais , Cebus , Ecologia , Frutas , Comportamento de Retorno ao Território Vital , Saguinus , Saimiri , Sementes , Suriname , Árvores
16.
Folia Primatol (Basel) ; 30(3): 161-93, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-720997

RESUMO

The locomotor and postural behavior of Ateles geoffroyi and Ateles paniscus was studied in Panama and Surinam. Ateles locomotion can be divided into five patterns on the basis of limb usage: quadrupedal walking and running, suspensory locomotion, climbing, bipedalism and leaping. The first three are commonly used in both locomotion during travel and locomotion during feeding, but climbing (especially 'horizontal climbing') is the most important pattern during feeding. Most Ateles locomotion takes place on twigs and branches, with twigs playing a greater role in feeding than in travel. Feeding postures are mainly suspensory and seated, short resting postures are suspensory, seated and standing, and long resting postures are almost entirely seated and reclining. Twigs are the most important supports in feeding postures, but branches are much more important in resting postures. The results of this study indicate that the quadrumanous climbing, forelimb-dominated locomotion during feeding that FLEAGLE considers the primary hominoid adaptation is also characteristic of Ateles.


Assuntos
Locomoção , Postura , Primatas , Animais
17.
Primates Med ; 10: 20-9, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-417322

RESUMO

Brazilian and Guianan callitrichids are categorized as endangered, vulnerable, common or status unknown. Endangered species should not be used in biomedical research and a continuing supply of wild-caught vulnerable species is also out of the question. Common species, on the other hand, could withstand limited sustained yield cropping without difficulty. Species categorized as status unknown should not be used until more data on them become available. Callitrichids have a higher reproductive potential than other New World monkeys, are for the most part quite adaptable, and are rarely hunted for food or captured as pets locally. Widespread habitat destruction is the major threat to their survival and species with naturally small ranges in areas of high human activity (e.g. Leontopithecus, Callithrix flaviceps) are in the greatest danger.


Assuntos
Callitrichinae , Animais , Brasil , Ecologia , Guiana Francesa , Geografia , Guiana , Haplorrinos , Suriname
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