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241.
Tracing the geographic origin of traded leopard body parts in the indian subcontinent with DNA‐based assignment tests
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Samrat Mondol Vanjulavalli Sridhar Prasanjeet Yadav Sanjay Gubbi Uma Ramakrishnan 《Conservation biology》2015,29(2):556-564
Illicit trade in wildlife products is rapidly decimating many species across the globe. Such trade is often underestimated for wide‐ranging species until it is too late for the survival of their remaining populations. Policing this trade could be vastly improved if one could reliably determine geographic origins of illegal wildlife products and identify areas where greater enforcement is needed. Using DNA‐based assignment tests (i.e., samples are assigned to geographic locations), we addressed these factors for leopards (Panthera pardus) on the Indian subcontinent. We created geography‐specific allele frequencies from a genetic reference database of 173 leopards across India to infer geographic origins of DNA samples from 40 seized leopard skins. Sensitivity analyses of samples of known geographic origins and assignments of seized skins demonstrated robust assignments for Indian leopards. We found that confiscated pelts seized in small numbers were not necessarily from local leopards. The geographic footprint of large seizures appeared to be bigger than the cumulative footprint of several smaller seizures, indicating widespread leopard poaching across the subcontinent. Our seized samples had male‐biased sex ratios, especially the large seizures. From multiple seized sample assignments, we identified central India as a poaching hotspot for leopards. The techniques we applied can be used to identify origins of seized illegal wildlife products and trade routes at the subcontinent scale and beyond. 相似文献
242.
The interspecific preferences of fishes for different depths and habitats suggest fishers could avoid unwanted catches of some species while still effectively targeting other species. In pelagic longline fisheries, albacore (Thunnus alalunga) are often caught in relatively cooler, deeper water (>100 m) than many species of conservation concern (e.g., sea turtles, billfishes, and some sharks) that are caught in shallower water (<100 m). From 2007 to 2011, we examined the depth distributions of hooks for 1154 longline sets (3,406,946 hooks) and recorded captures by hook position on 2642 sets (7,829,498 hooks) in the American Samoa longline fishery. Twenty‐three percent of hooks had a settled depth <100 m. Individuals captured in the 3 shallowest hook positions accounted for 18.3% of all bycatch. We analyzed hypothetical impacts for 25 of the most abundant species caught in the fishery by eliminating the 3 shallowest hook positions under scenarios with and without redistribution of these hooks to deeper depths. Distributions varied by species: 45.5% (n = 10) of green sea turtle (Chelonia mydas), 59.5% (n = 626) of shortbill spearfish (Tetrapturus angustirostris), 37.3% (n = 435) of silky shark (Carcharhinus falciformis), and 42.6% (n = 150) of oceanic whitetip shark (C. longimanus) were caught on the 3 shallowest hooks. Eleven percent (n = 20,435) of all tuna and 8.5% (n = 10,374) of albacore were caught on the 3 shallowest hooks. Hook elimination reduced landed value by 1.6–9.2%, and redistribution of hooks increased average annual landed value relative to the status quo by 5–11.7%. Based on these scenarios, redistribution of hooks to deeper depths may provide an economically feasible modification to longline gear that could substantially reduce bycatch for a suite of vulnerable species. Our results suggest that this method may be applicable to deep‐set pelagic longline fisheries worldwide. Compensaciones entre Captura, Captura Accesoria y Valores Asentados en la Pesquera de Línea Larga de Samoa Americana 相似文献
243.
中美贸易争端背景下,评估中国大豆贸易对全球水和耕地资源的影响,对粮食安全和环境可持续意义重大。基于GTAP(Global Trade Analysis Project)模型,以中国及其主要大豆供应国(美国、巴西、阿根廷、乌拉圭、加拿大)为研究区,模拟中国对美国大豆加征关税前后的情景,评估相应情景下中国大豆进口对全球水和耕地资源的影响。结果表明:在加征关税前后情景下,中国大豆进口总量保持稳定,进口量中供应国之间占比变化较大,特别是加征关税后美国占比明显减少;虚拟耕地进口总量保持稳定,虚拟水进口总量减少;在全球尺度上,从巴西进口大豆水资源利用率最高、从美国进口大豆耕地资源利用率最高。取消除美国外其他四国关税可同时减少全球水和耕地资源的消耗。 相似文献
244.
Macdonald DW Johnson PJ Albrechtsen L Dutton A Seymour S Dupain J Hall A Fa JE 《Conservation biology》2011,25(6):1220-1228
Spatially extensive patterns of bushmeat extraction (and the processes underlying these patterns) have not been explored. We used data from a large sample (n= 87) of bushmeat trading points in urban and rural localities in Nigeria and Cameroon to explore extraction patterns at a regional level. In 7,594 sample days, we observed 61,267 transactions involving whole carcasses. Rural and urban trading points differed in species for sale and in meat condition (fresh or smoked). Carcass price was principally associated with body mass, with little evidence that taxonomic group (primate, rodent, ungulate, or mammalian carnivore) affected price. Moreover, meat condition was not consistently associated with price. However, some individual species were more expensive throughout the region than would be expected for their size. Prices were weakly positively correlated with human settlement size and were highest in urban areas. Supply did not increase proportionally as human settlement size increased, such that per capita supply was significantly lower in urban centers than in rural areas. Policy options, including banning hunting of more vulnerable species (those that have low reproductive rates), may help to conserve some species consumed as bushmeat because carcass prices indicate that faster breeding, and therefore the more sustainable species, may be substituted and readily accepted by consumers. 相似文献
245.
中国开展排污权有偿使用和交易试点以来,经过各试点地区的积极探索取得了实质性进展,环境容量的资源意识不断得到提升,部分地区已经初步建立了排污指标有偿使用和交易机制.由于此项工作尚处于起步和探索阶段,仍存在政策和法律滞后、与其他政策关联不足、试点范围局限等问题.提出从完善立法、加强政策关联、注重政策公平以及扩大试点范围等推... 相似文献
246.
对CDM市场的项目类型进行了归纳与分析,总结了CDM项目类型与项目注册过程中的问题,对CDM项目交易市场的现状及制度进行了探讨,并提出了相关建议。 相似文献
247.
248.
在全球气候变化的大背景下,发展低碳经济已经成为全球性共识;同时作为发展低碳经济前沿领域的碳交易市场也得以迅速发展。本文简要综述了我国农业碳汇交易研究和碳交易市场发展的现状及其存在的问题,分析了在福建建立海峡两岸农业碳汇交易平台的政策机遇和区域优势,提出了构建闽台农业碳汇交易中心的规划设想,并结合规划设想提出了要加强碳汇农业理论与节能减排技术、低碳农业发展规划与综合评估体系、农业碳汇交易机制、监测及其认证体系等农业碳汇研究的方向与建议。 相似文献
249.
随着我市饮食娱乐服务业的蓬勃发展,产生的污染随之增多,如何处理该类项目的环境管理问题成为环保部门的一项重要任务. 相似文献
250.