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81.
This paper uses the gravity model to examine the effect of environmental regulations on pork trade flows between different regions within China.We apply a linear programming tool to estimate pork trade flows from 2000 to 2008,and discuss the environmental acts on livestock pollution and income level to proxy environmental regulations.We use OLS regression and panel data with dummy variable in the cross-sectional GLS estimation.Our results indicate that the gap of environmental regulations between trade partners has a positive relationship with pork trade flows,and the difference in environmental regulations changes the traditional comparative advantage pattern to some extent.This paper provides convincing evidence for the pollution haven effect on livestock in China. 相似文献
82.
Overharvesting is one of the greatest threats to species survival. Farming overharvested species is a conservation strategy that can meet growing market demand and conserve wild populations of the target species. This strategy is compatible with the international community's desire to uphold the right of local communities to use biological resources to support their livelihoods. However, studies investigating whether farming can alleviate poaching pressure have focused almost exclusively on animals. To address the shortfall in plant-focused studies, we compiled information on commercial cultivation of threatened plants to assess its conservation benefits. Because China's rising middle class has rapidly intensified demand for wildlife products, we searched the scientific literature published in Chinese (China National Knowledge Infrastructure and Baidu) and in English. We found 32 reports that contained data on 193 internationally or nationally threatened plant species that were under commercial cultivation. These reports showed that cultivations of 82% of the 193 species were sustained by collecting whole plants from the wild periodically or continuously. Although based on a small sample size, species that were maintained in cultivation only through artificial propagation or seeds collected in the wild were likely associated with a reported reduction in wild harvesting of whole plants. Even so, results of correlation analyses suggested that production system, scale, and when a species began being cultivated had little effect on conservation status of the species, either globally or in China. However, species brought into cultivation relatively recently and on a smaller scale were more likely to have undergone a reduction in collecting pressure. Farming of nonmedicinal plants was most problematic for species conservation because wild plants were laundered (i.e., sold as cultivated plants). For effective conservation, policy to guide cultivation operations based on the target species’ biological characteristics, cultural significance, market demand, and conservation status is needed. 相似文献
83.
J. Berton C. Harris Morgan W. Tingley Fangyuan Hua Ding Li Yong J. Marion Adeney Tien Ming Lee William Marthy Dewi M. Prawiradilaga Cagan H. Sekercioglu Suyadi Nurul Winarni David S. Wilcove 《Conservation biology》2017,31(2):394-405
The trade in wild animals involves one‐third of the world's bird species and thousands of other vertebrate species. Although a few species are imperiled as a result of the wildlife trade, the lack of field studies makes it difficult to gauge how serious a threat it is to biodiversity. We used data on changes in bird abundances across space and time and information from trapper interviews to evaluate the effects of trapping wild birds for the pet trade in Sumatra, Indonesia. To analyze changes in bird abundance over time, we used data gathered over 14 years of repeated bird surveys in a 900‐ha forest in southern Sumatra. In northern Sumatra, we surveyed birds along a gradient of trapping accessibility, from the edge of roads to 5 km into the forest interior. We interviewed 49 bird trappers in northern Sumatra to learn which species they targeted and how far they went into the forest to trap. We used prices from Sumatran bird markets as a proxy for demand and, therefore, trapping pressure. Market price was a significant predictor of species declines over time in southern Sumatra (e.g., given a market price increase of approximately $50, the log change in abundance per year decreased by 0.06 on average). This result indicates a link between the market‐based pet trade and community‐wide species declines. In northern Sumatra, price and change in abundance were not related to remoteness (distance from the nearest road). However, based on our field surveys, high‐value species were rare or absent across this region. The median maximum distance trappers went into the forest each day was 5.0 km. This suggests that trapping has depleted bird populations across our remoteness gradient. We found that less than half of Sumatra's remaining forests are >5 km from a major road. Our results suggest that trapping for the pet trade threatens birds in Sumatra. Given the popularity of pet birds across Southeast Asia, additional studies are urgently needed to determine the extent and magnitude of the threat posed by the pet trade. 相似文献
84.
排污权交易定价下的COD和氨氮削减成本分析研究 总被引:1,自引:0,他引:1
调查测算了工业废水COD和氨氮削减成本并进行了分析。总成本中折旧费和日常运行费各占35%和65%;COD和氨氮削减成本为1 287元/t~29 035元/t和2 433元/t~46 560元/t,加权均值为4 936元/t和17 755元/t,二者之比为3.60∶1,90%置信区间为(4 647,8 514)和(13 989,24 617);70%和63.2%的企业以6 837元/t和20 083元/t以内的成本削减了73.7%的COD和42.1%的氨氮。不同企业和行业COD和氨氮削减成本差异明显,以概率分布确定综合成本用于排污权交易定价可能更合理。 相似文献
85.
环境规制、要素禀赋与我国贸易模式的实证分析 总被引:3,自引:0,他引:3
傅京燕 《中国人口.资源与环境》2008,18(6)
当今的全球化趋势在导致贸易壁垒不断削减的同时,各国的环境规制却随之不断提升.本文使用世界银行的产业污染排放系统(IPPS)对我国制造业进行细分,运用显示性比较优势指数方法,把环境规制因素和要素禀赋因素同时引入到对贸易模式的分析.结果表明,贸易开放使我国的比较优势得以发挥,这表现为更多地专业化于清洁的劳动密集型产业,因此,即使总的污染排放有所增加,但单位产出的污染排放强度会有所下降.但另一方面,贸易开放使外资的流入增加,而资本累积是影响污染排放强度的主要因素,这必将导致我国的制造业结构更多地转向污染产业.因此,随着我国对外开放程度的加深,污染排放必呈上升态势.针对污染排放增加的原因,有效地利用产业政策和环境政策对实现资源环境的可持续发展是相当重要的. 相似文献
86.
87.
排污权交易及其规范 总被引:6,自引:0,他引:6
邢晓军 《中国人口.资源与环境》1998,8(2):21-24
排污权理论的产生是对环境认识深化的结果。市场对环境资源配置的结果必定要求进行排污权交易。目前我国应根据个案试点的经验,建立和完善排污权交易市场,加大污染治理的力度。 相似文献
88.
全球经济一体化中的环境壁垒与我国环境和贸易政策选择 总被引:2,自引:0,他引:2
本文纵观全球经济贸易格局和环境问题特点,指出了环境壁垒是影响全球贸易和环境的重要因素,分析了环境壁垒产生的本质,提出了国际贸易的新形势下我国如何实现可持续经济发展的贸易和环境政策。 相似文献
89.
90.
绿色贸易壁垒能促进广大发展中国家不断提高产品的环境保护水平,保护本国的生态环境,但在环保大潮的冲击下,一些贸易企业会由于产品不符合要求而面临出口困境。本文以绿色贸易壁垒产生的原因及应采取的措施等方面进行论述,指出绿色贸易壁垒既是挑战又是机遇,要正确认识绿色贸易壁垒。 相似文献