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91.
Chelsea Dale 《Local Environment》2015,20(11):1309-1321
In 2008, the Cowichan Tribes of British Columbia re-established a traditional fishing weir on the Cowichan River. After being banned by the Canadian Government for nearly 70 years, the reintroduction of the Cowichan weir has served to revitalise Cowichan cultural traditions, and after a century of hostility, is creating an opportunity for more collaborative approaches for salmon conservation. This paper demonstrates that the reintroduction of indigenous conservation practices into western systems of fisheries management can be complementary rather than conflicting to conservation objectives. However, while collaborative salmon conservation has been a positive outcome, the reintroduction of the Cowichan weir is also symbolic of the conflict that remains between the Cowichan and the Government of Canada over competing territorial claims, the legitimacy of an imposed western legal tradition, and the ultimate control of the Cowichan River fishery.  相似文献   
92.
Irrigation districts (IDs) in the American west are highly diverse in their economic attributes and local water scarcity circumstances. This diversity may affect reallocative action via water transactions as scarcity rises. The institutional background defining and constraining IDs is described here. For a Texas study region the progress of permanent water right transfers involving IDs is documented and examined. An econometric analysis of multiple decades of ID water transfer activities in the Lower Rio Grande Valley finds that IDs with larger initial water right holdings and higher populations in nearby cities are more likely to participate in agricultural‐to‐municipal water transfer activities. The findings suggest that consolidation of smaller water right holding IDs may be an avenue for quickening the pace of reallocation, especially in more populated areas.  相似文献   
93.
总量控制下环境容量产权交易及政府行为分析   总被引:1,自引:2,他引:1  
吕伟明 《四川环境》2003,22(3):49-52,65
利用经济学的原理,本文分析了环境容量的经济特点(不是环境容量产权交易的特征),提出了环境容量产权交易的可行性和必要性。同时针对政府在环境容量产权交易中的作用进行了必要的分析。  相似文献   
94.
This paper applies a property rights framework to federal mineral lands in the western United States from the enactment of the Mining Law in 1872 until the enactment of the Mineral Leasing Act for fossil fuels in 1920. There are two principal findings. First, the Mining Law appears to have been an effective means for assigning rights to mineral stocks on public lands (at least through 1920). This conclusion is supported by evidence from claim disputes in the West. Second, the impetus for the Mineral Leasing Act did not derive from the different physical characteristics of hardrock minerals and petroleum. The relevance of these conclusions to contemporary mineral policy is also discussed.  相似文献   
95.
Several writers on animal ethics defend the abolition of most or all animal agriculture, which they consider an unethical exploitation of sentient non-human animals. However, animal agriculture can also be seen as a co-evolution over thousands of years, that has affected biology and behavior on the one hand, and quality of life of humans and domestic animals on the other. Furthermore, animals are important in sustainable agriculture. They can increase efficiency by their ability to transform materials unsuitable for human consumption and by grazing areas that would be difficult to harvest otherwise. Grazing of natural pastures is essential for the pastoral landscape, an important habitat for wild flora and fauna and much valued by humans for its aesthetic value. Thus it seems that the environment gains substantially when animals are included in sustainable agricultural systems. But what about the animals themselves? Objections against animal agriculture often refer to the disrespect for animals’ lives, integrity, and welfare in present intensive animal production systems. Of the three issues at stake, neither integrity nor animal welfare need in principle be violated in carefully designed animal husbandry systems. The main ethical conflict seems to lie in the killing of animals, which is inevitable if the system is to deliver animal products. In this paper, we present the benefits and costs to humans and animals of including animals in sustainable agriculture, and discuss how to address some of the ethical issues involved.  相似文献   
96.
芜湖市郊土壤污染对土壤动物群落结构的影响   总被引:8,自引:0,他引:8  
研究表明,芜湖市郊农田土壤动物群落的组成与数量随污染程度的加重而减少,土壤动物密度也呈同样的变化趋势,特别是中小型土壤动物,优势类群数量发生较大消长,常见类群和稀有类群的组成逐渐减少.多样性指数H与重金属污染程度之间关系因受到季节的影响而变得复杂:冬季和初夏污染较重样地优势类群数量减少,群落均匀性指数E增加而优势度指数C减小,多样性指数H较高;而春季处于过渡阶段,某些类群(如螨类)数量爆发,C增高,H较小.土壤动物群落密度一类群指数DG随污染加重而减小.受到重金属污染的农田土壤动物的表聚性减弱,甚至出现逆分布现象.图1表4参15  相似文献   
97.
根据水权交易市场建设的基本要求,文章设计了郑州市地下水自备井计划用水交易市场,并对相关的水资源管理制度改革提出了建议。郑州市地下水自备井计划用水交易市场首先需要明晰初始水权、实施总量控制和完善监测计量系统;然后建立相应的市场交易制度,包括年度用水计划制定、跨年度用水指标使用、交易产品选择、交易周期选择、交易价格生成和网上在线交易系统建设等。在建立水权交易市场以后,还需要对现有的水资源管理制度进行改革,包括新水权发放、生态与环境影响评价、市场信息公布、现有的用水计划制定和超计划累进加价制度改革等。  相似文献   
98.
The continuing existence of zoos and their good purposes such as conservation, science, education, and recreation, can be ethically justified only if zoos guarantee the welfare of their animals. The usual criteria for measuring animal welfare in zoos are physical health, long life, and reproduction. This paper looks at these criteria and finds them insufficient. Additional criteria are submitted to expand the range of welfare considerations: natural and abnormal behavior; freedom and choice; and dignity. All these criteria should play a role in analyzing zoo animal welfare and interests but dignity has the overriding part because it impacts on both animal and human interests.  相似文献   
99.
红外光度法测定石油类和动植物油常见问题探讨   总被引:2,自引:0,他引:2  
根据石油类在波数为2930cm-1、2960 cm-1、3030 cm-1全部或部分谱带处有物征吸收的原理,采用红外光度测油仪和水样絮凝富集技术测定石油类、动植物油。  相似文献   
100.
流域管理:权力产权的外部性问题   总被引:3,自引:0,他引:3  
水资源的自然、经济和社会属性要求政府对流域的开发和利用进行管理,以解决个体使用者的外部性问题.但实际上由于政府并不是只有单一目标的统一组织,在分权体制下,不同区域、部门的政府单元掌握着实际权力.由于权力也存在外部性,各管理区域、部门之间存在利益冲突,导致政府的管理失效.解决政府权力外部性的办法:一是要转变政府职能,改变政府的激励机制;二是严格界定各政府单元的权力界限,对流域进行统一管理.  相似文献   
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