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How Many Species Are There in Brazil? 总被引:2,自引:0,他引:2
Abstract: We produced estimates of the total number of species currently known and the total numbers predicted to occur in Brazil. Lists of species recorded in Brazil were obtained from specialists and the literature. For taxa lacking information on total known species, we produced estimates based on bootstrap resampling from a set of 87 taxa with checklists for Brazil and the world. The estimated proportion of Brazilian species was 9.5% of the world total (95% CI, 8.5 to 11.5%). From this we estimated a known Brazilian biota of 170,000 to 210,000 species. We used a similar procedure to estimate Brazil's total biota—known plus undiscovered. Based on 17 relatively well-known taxa, the average Brazilian share in the world's biota was estimated at 13.1% (CI 10.0 to 17.6%). Accordingly we estimated the country's total biota at 1.8 million species (CI 1.4 to 2.4 million). Given that the Neotropics is the least-studied major region of the world, these figures are still likely to be underestimates and hence may be taken as a lower bound of the actual proportion of the world's species that occur in Brazil. Scientists, policy makers, and citizens will find these numbers useful in appreciating the magnitude of the tasks involved in surveying, describing, and conserving the country's biota. The numbers also bring proposals and priorities into a more realistic perspective. 相似文献
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C. GUILHERME BECKER† CARLOS R. FONSECA‡ CÉLIO F. B. HADDAD§ PAULO I. PRADO 《Conservation biology》2010,24(1):287-294
Abstract: Most amphibian species have biphasic life histories and undergo an ontogenetic shift from aquatic to terrestrial habitats. In deforested landscapes, streams and forest fragments are frequently disjunct, jeopardizing the life cycle of forest-associated amphibians with aquatic larvae. We tested the impact of habitat split—defined as human-induced disconnection between habitats used by different life-history stages of a species—on four forest-associated amphibian species in a severely fragmented landscape of the Brazilian Atlantic Forest. We surveyed amphibians in forest fragments with and without streams (referred to as wet and dry fragments, respectively), including the adjacent grass-field matrix. Our comparison of capture rates in dry fragments and nearby streams in the matrix allowed us to evaluate the number of individuals that engaged in high-risk migrations through nonforested habitats. Adult amphibians moved from dry fragments to matrix streams at the beginning of the rainy season, reproduced, and returned at the end of the breeding period. Juveniles of the year moved to dry fragments along with adults. These risky reproductive migrations through nonforested habitats that expose individuals to dehydration, predation, and other hazards may cause population declines in dry fragments. Indeed, capture rates were significantly lower in dry fragments compared with wet fragments. Declining amphibians would strongly benefit from investments in the conservation and restoration of riparian vegetation and corridors linking breeding and nonbreeding areas. 相似文献
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Challenges and Opportunities for Biodiversity Conservation in the Brazilian Atlantic Forest 总被引:8,自引:0,他引:8
MARCELO TABARELLI LUIZ PAULO PINTO† JOSÉ M. C. SILVA‡ MÁRCIA HIROTA§ LÚCIO BEDʆ 《Conservation biology》2005,19(3):695-700
Abstract: With endangered status and more than 8,000 endemic species, the Atlantic Forest is one of the world's 25 biodiversity hotspots. Less than 100,000 km2 (about 7%) of the forest remains. In some areas of endemism, all that is left are immense archipelagos of tiny and widely separated forest fragments. In addition to habitat loss, other threats contributing to forest degradation include the harvesting of firewood, illegal logging, hunting, plant collecting, and invasion by alien species—all despite the legislation that exists for the forest's protection. More than 530 plants and animals occurring in the forest are now officially threatened, some at the biome level, some throughout Brazil, and some globally. Many species have not been recorded in any protected areas, indicating the need to rationalize and expand the parks system. Although conservation initiatives have increased in number and scale during the last two decades, they are still insufficient to guarantee the conservation of Atlantic Forest biodiversity. To avoid further deforestation and massive species loss in the Brazilian Atlantic Forest, the challenge is to integrate the diverse regulations, public policies, new opportunities, and incentive mechanisms for forest protection and restoration and the various independent projects and programs carried out by governments and nongovernmental organizations into a single and comprehensive strategy for establishing networks of sustainable landscapes throughout the region. 相似文献
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PAULO M. MARTINS DA COSTA PAULO M. VAZ-PIRES FERNANDO M. BERNARDO 《Journal of environmental science and health. Part. B》2013,48(8):1393-1403
Antibiotimicrobial resistance was investigated in 537 Enterococcus spp. isolates recovered from 22 samples of crude inflow, treated effluent and sludge collected in wastewater treatment plants of eight poultry slaughterhouses of Portugal. No significant differences (P > 0.05) were found in the resistance to each antimicrobial agent with regards to the origin of the sample (inflow, sludge and effluent). Many of the isolates displayed resistance to tetracycline (85.7%), erythromycin (45.7%), nitrofurantoin (34.0%) and rifampicin (17.8%). Resistance was also observed, but to a lesser extent, to ciprofloxacin (10.2%), ampicillin (8.0%), chloramphenicol (4.6%), vancomycin (0.9%) and gentamicin (0.4%). Resistance to three or more antimicrobial classes was present in 37.1% of the isolates. Wastewater treatment resulted in viable enterococci decrease between less than 1 log and 4 log; nevertheless, more than 4.4 × 105 colony forming units (CFU)/100 mL were present in the outflow of the plants and thus resistant enterococci are not prevented from reaching the general environment. 相似文献
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THOMAS M. LEWINSOHN§ RÉ VICTOR LUCCI FREITAS† PAULO INÁCIO PRADO‡ 《Conservation biology》2005,19(3):640-645
Abstract: As one of the world's prime megadiverse countries, Brazil holds an immense number of terrestrial invertebrates. Current knowledge of this biota is very heterogeneous. Several taxa are sufficiently well known to be used as indicators of ecological integrity or of endemism. The current Brazilian national and regional red lists include 130 terrestrial invertebrate species, of which 42% are butterflies. These lists are contingent on available knowledge, and many taxa that are omitted certainly include species at risk. Knowledge of various biomes and habitats is also quite irregular, with the Caatinga and Pantanal in need of more study, compared with the Atlantic Forest, the Amazon, and Cerrado. Canopy, host-associated, and soil faunas also need further intensive study. Invertebrate conservation will be promoted more effectively by habitat preservation and management rather than single-species initiatives. To this end, better geographic surveys of entire taxonomic or functional assemblages are needed. An improved understanding of the invertebrate role in ecosystem processes will strengthen enormously the case for their conservation. 相似文献
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