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1.
David M. Lapola José Maria C. da Silva Diego R. Braga Larissa Carpigiani Fernanda Ogawa Roger R. Torres Luis C. F. Barbosa Jean P. H. B. Ometto Carlos A. Joly 《Conservation biology》2020,34(2):427-437
Brazil hosts the largest expanse of tropical ecosystems within protected areas (PAs), which shelter biodiversity and support traditional human populations. We assessed the vulnerability to climate change of 993 terrestrial and coastal-marine Brazilian PAs by combining indicators of climatic-change hazard with indicators of PA resilience (size, native vegetation cover, and probability of climate-driven vegetation transition). This combination of indicators allows the identification of broad climate-change adaptation pathways. Seventeen PAs (20,611 km2) were highly vulnerable and located mainly in the Atlantic Forest (7 PAs), Cerrado (6), and the Amazon (4). Two hundred fifty-eight PAs (756,569 km2), located primarily in Amazonia, had a medium vulnerability. In the Amazon and western Cerrado, the projected severe climatic change and probability of climate-driven vegetation transition drove vulnerability up, despite the generally good conservation status of PAs. Over 80% of PAs of high or moderate vulnerability are managed by indigenous populations. Hence, besides the potential risks to biodiversity, the traditional knowledge and livelihoods of the people inhabiting these PAs may be threatened. In at least 870 PAs, primarily in the Atlantic Forest and Amazon, adaptation could happen with little or no intervention due to low climate-change hazard, high resilience status, or both. At least 20 PAs in the Atlantic Forest, Cerrado, and Amazonia should be targeted for stronger interventions (e.g., improvement of ecological connectivity), given their low resilience status. Despite being a first attempt to link vulnerability and adaptation in Brazilian PAs, we suggest that some of the PAs identified as highly or moderately vulnerable should be prioritized for testing potential adaptation strategies in the near future. 相似文献
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G G Pyle S M Swanson D M Lehmkuhl 《Environmental pollution (Barking, Essex : 1987)》2002,116(2):243-255
Elevated concentrations of arsenic, nickel, and molybdenum in aquatic systems around northern Saskatchewan uranium mines are an environmental concern. Early life stage fathead minnows were used to assess toxicity from several aquatic systems near the Key Lake and Rabbit Lake uranium operations. Hatching success of fish embryos exposed to waters receiving contaminants associated with uranium ore milling was reduced by 32-61% relative to controls. Mortality differed in two lakes receiving mill effluents because of opposing factors influencing metal toxicity (i.e. low pH and high hardness). In one mill receiving water (Fox Lake), larval mortality was 0%, whereas mortality was 85% in water collected from a downstream location (Unknown Lake). Fish embryos exposed to open-pit dewatering effluent receiving waters, or water from a flooded open pit (i.e. pit waters), hatched 26-39% earlier than those exposed to reference or control water. The combination of low water hardness and elevated nickel concentrations in pit waters contributed to the early hatching. Egg hatchability and hatching time were more sensitive indicators of toxicity than 'standard' endpoints, like larval mortality and growth. Current regulatory emphasis on single contaminants and standard toxicological endpoints should be re-evaluated in light of the complex interaction among confounding variables such as pH, hardness. conductivity, and multi-metal mixtures. 相似文献
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JHERIME L. KELLERMANN MATTHEW D. JOHNSON AMY M. STERCHO STEVEN C. HACKETT 《Conservation biology》2008,22(5):1177-1185
Abstract: Coffee farms can support significant biodiversity, yet intensification of farming practices is degrading agricultural habitats and compromising ecosystem services such as biological pest control. The coffee berry borer (Hypothenemus hampei) is the world's primary coffee pest. Researchers have demonstrated that birds reduce insect abundance on coffee farms but have not documented avian control of the berry borer or quantified avian benefits to crop yield or farm income. We conducted a bird‐exclosure experiment on coffee farms in the Blue Mountains, Jamaica, to measure avian pest control of berry borers, identify potential predator species, associate predator abundance and borer reductions with vegetation complexity, and quantify resulting increases in coffee yield. Coffee plants excluded from foraging birds had significantly higher borer infestation, more borer broods, and greater berry damage than control plants. We identified 17 potential predator species (73% were wintering Neotropical migrants), and 3 primary species composed 67% of migrant detections. Average relative bird abundance and diversity and relative resident predator abundance increased with greater shade‐tree cover. Although migrant predators overall did not respond to vegetation complexity variables, the 3 primary species increased with proximity to noncoffee habitat patches. Lower infestation on control plants was correlated with higher total bird abundance, but not with predator abundance or vegetation complexity. Infestation of fruit was 1–14% lower on control plants, resulting in a greater quantity of saleable fruits that had a market value of US$44–$105/ha in 2005/2006. Landscape heterogeneity in this region may allow mobile predators to provide pest control broadly, despite localized farming intensities. These results provide the first evidence that birds control coffee berry borers and thus increase coffee yield and farm income, a potentially important conservation incentive for producers. 相似文献
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