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21.
Kimberly K. Smith 《Journal of Agricultural and Environmental Ethics》2009,22(3):241-256
Elizabeth Anderson’s “pluralist–expressivist” value theory, an alternative to the understanding of value and rationality underlying
the “rational actor” model of human behavior, provides rich resources for addressing questions of environmental and animal
ethics. It is particularly well-suited to help us think about the ethics of commodification, as I demonstrate in this critique
of the pet trade. I argue that Anderson’s approach identifies the proper grounds for criticizing the commodification of animals,
and directs our attention to the importance of maintaining social practices and institutions that respect the social meanings of animals. Her theory alone, however, does not adequately address the role of the state in this project. Drawing on social
contract theory to fill this gap, I conclude that the state’s role in regulating the pet trade should be limited to ensuring
the welfare of animals in the stream of commerce, not prohibiting their mass marketing altogether. 相似文献
22.
The level of water was manipulated in a freshwater wetland, with the aim of enhancing abundances of benthic animals and, ultimately, improving habitat for feeding birds (Japanese Snipe, Gallinago hardwickii). We tested whether these actions had the predicted and desired effects on benthic animals, by contrasting changes in two managed locations to one control location which was left unmanipulated. The number of taxa and abundances of chironomids decreased strongly and significantly in the manipulated locations, while the abundance of oligochaetes appeared to vary in a seasonal manner. Temporal variability of the structure and composition of assemblages was also increased in manipulated locations. Such effects have previously been suggested to indicate stress in benthic assemblages. Therefore, in contrast to what was predicted, managerial actions made benthic fauna less abundant and thus, less suitable as habitat for feeding birds. Several general lessons can be learned from these results. (1) Effects of managerial actions like these are difficult to predict a priori and can only be reliably evaluated with an experimental framework. (2) Because abundances of animals vary naturally, evaluations of managerial actions must include appropriate spatial replication. (3) Sampling at hierarchical temporal scales is important, because abundances of animals may vary in an unpredictable manner at short temporal scales and because changes in temporal variability may be a symptom of stress. (4) Combined use of uni- and multivariate techniques provides a comprehensive set of tools to assess the effects of restoration and creation of new habitats. Finally, these results emphasise the need for clear predictions about desired outcomes and specific experimental plans about how to test whether the desired results were achieved, before managerial actions are taken. Although this is often very difficult to achieve in real situations, it is necessary for practices of management to evolve on the basis of sound empirical experience. 相似文献
23.
M. H. Wong 《Environmental management》1981,5(2):135-145
Disposal of iron ore tailings along the shore of Tolo Harbour, Hong Kong has altered the adjacent environment. Due to the ever-expanding population, the vast development of various industries, and the lack of sanitary control, the existing pollution problem of Tolo Harbour is serious. The iron ore tailings consist of a moderate amount of various heavy metals, e.g., copper, iron, manganese, lead, zinc, and a lower level of macronutrients. A few living organisms have been found colonizing this manmade habitat. Higher metal contents were also found in the tissue ofPaphia sp. (clam);Scopimera intermedia (crab);Chaetomorpha brychagona (green alga);Enteromorpha crinita (green alga); andNeyraudia reynaudiana (grass). The area can be reclaimed by surface amelioration using inert materials, soils, or organic substrates, and by direct seeding, using nontolerant and tolerant plant materials. Reclamation of the tailings would improve the amenity of the adjacent environment and also mitigate pollution escaping to the sea. 相似文献
24.
25.
底泥疏浚对湖泊内源削减具有重要的作用,是富营养化湖泊内源治理的重要技术之一.以太湖疏浚区为对象,估算了近十余年疏浚对内源负荷的削减量,并评估了太湖北部竺山湖和梅梁湖的底泥疏浚效果.结果表明,太湖累计疏浚的4 200万m3底泥,共计清除了底泥中氮约6.26万t,总磷约1.83万t,有机质约117万t,相当于清除了蓄积于底泥中二十余年的外源污染物输入量.对于外源控制较好的梅梁湖,底泥疏浚后5 a内水质改善明显,随后出现反弹,但仍有效削减了表层底泥总氮和总磷含量.相反,对于外源输入仍较大的竺山湖,疏浚十余年后,底泥内源又回复到浚前水平.对竺山湖疏浚区开展了长达6 a的底栖生物群落跟踪评估,发现疏浚初期对底栖生物群落具有一定的影响,但浚后2 a,底栖生物密度与生物量等指标已接近浚前水平. 6 a后,疏浚区与未疏浚区的底栖生物群落多样性指数已无差别.结果也表明,底泥疏浚对湖体内源具有较好的控制效果,且疏浚效果维持程度与外源输入强度密切相关.此外,长期来看,疏浚区底栖生物群落依靠自恢复能力可达到浚前水平,疏浚不会对底栖生物群落结构造成影响. 相似文献
26.
Zooplankton samples, collected in autumn 1996 from two stations in the Gulf of Rapallo, Ligurian Sea (Rapallo Harbour and Prelo Bay, which is a more open site with lower human impacts) were analysed. at both stations, the community was dominated by copepods (mainly juveniles and adults of different species of Acartia and Oithona) and meroplankton (mainly polychaete larvae). Total zooplankton abundance in the harbour waters was significantly higher than in the nearby bay. the occurrence of Acartia grani in Rapallo Harbour and Pteriacartia josephinae in Prelo Bay is noteworthy, as they are reported for the first time in the Ligurian Sea, and A. grani has not previously been recorded to the Italian coastline. A three-day benthic chamber experiment aimed to quantify nutrient fluxes between the sediment and water column was performed in the Rapallo Harbour: the profound effects of confinement on the composition and abundance of zooplankton within the incubation chamber are discussed. 相似文献
27.
Diffusive fluxes of elements (NO-2, NO-3, NH+4, SiO2, PO3-4, Cl-, SO2-4, Fe, Mn) have been measured by applying the Fick's first law in two stations of the Tigullio Gulf: the first one characterized by sandy sediments rich in vegetal detritus and the second one, located to within the tourist harbour, characterized by a silty-clay sediments.
Benthic fluxes were measured only in the second station by means of benthic chamber experiments. Although the significant presence of dissolved oxygen in the surface sediments, and the evidence of processes usually occurring in oxidised sediments such as nitrification, both stations also presented characteristics of anoxic sediments such as high oxygen consumption rate and high pore water concentrations of ion, manganese and N-ammonia and reactive orthophosphate.
In both stations, sediments seemed to represent a potential source for most of the chemical species studied, although fluxes were not confirmed for ion, manganese and reactive orthophosphate in benthic chamber experiments.
Diffusive fluxes presented a general agreement for both stations, with higher fluxes of N-nitrate and N-nitrite at the first station were oxidative processes of N-ammonia in the upper layer of the sediments seemed to be more active. the comparison between diffusive and benthic fluxes showed a possible contribution of bioturbation. 相似文献
Benthic fluxes were measured only in the second station by means of benthic chamber experiments. Although the significant presence of dissolved oxygen in the surface sediments, and the evidence of processes usually occurring in oxidised sediments such as nitrification, both stations also presented characteristics of anoxic sediments such as high oxygen consumption rate and high pore water concentrations of ion, manganese and N-ammonia and reactive orthophosphate.
In both stations, sediments seemed to represent a potential source for most of the chemical species studied, although fluxes were not confirmed for ion, manganese and reactive orthophosphate in benthic chamber experiments.
Diffusive fluxes presented a general agreement for both stations, with higher fluxes of N-nitrate and N-nitrite at the first station were oxidative processes of N-ammonia in the upper layer of the sediments seemed to be more active. the comparison between diffusive and benthic fluxes showed a possible contribution of bioturbation. 相似文献
28.
S. A. Frenzel 《Journal of the American Water Resources Association》1990,26(2):279-287
ABSTRACT: Aquatic communities in the Boise River were examined from October 1987 to March 1988 to determine whether they were adversely affected by trace elements in effluents from two Boise wastewater treatment facilities. Trace-element concentrations in the Boise River were less than or near analytical-detection levels and were less than chronic toxicity criteria when detectable. Insect communities colonizing artificial substrates upstream and downstream from the wastewater treatment facilities were strongly associated, and coefficients of community loss indicated that effluents had benign enriching effects. The distributions of trace-element-intolerant mayflies indicated that trace-element concentrations in effluents did not adversely affect intolerant organisms in the Boise River. Condition factor of whitefish was significantly increased downstream from the Lander Street wastewater treatment facility and was significantly decreased downstream from the West Boise wastewater treatment facility. 相似文献
29.
Florence Burgat 《Journal of Agricultural and Environmental Ethics》2004,17(3):223-248
The question of the imperatives induced by the Gandhian concept of non-violence towards animals is an issue that has been neglected by specialists on the thinking of the Mahatma. The aim of this article is to highlight the systematic – and significant – character of this particular aspect of his views on non-violence. The first part introduces the theoretical foundations of the duty of non-violence towards animals in general. Gandhi's critical interpretation of cow-protection, advocated by Hinduism, leads to a general reflection on the duty of non-violence towards animals, the cow being transformed into the representative of all “dumb creation.” The approach adopted by Gandhi to solving the problem of cow-protection focuses on its practical dimensions and is based primarily on reforming animal husbandry. What limits should be imposed on the exploitation of farm animals within the framework of non-violence? Gandhi devoted nearly 30 years to elaborating an animal husbandry system that would be both economically viable and in conformity with the universal ethical principles he drew from religions (especially Hinduism). The interdiction to kill is absolute, since Gandhi not only rejects the breeding of farm animals for the purposes of butchery but also the slaughtering of animals that are no longer capable of providing the services required of them. He therefore concentrated his efforts on drawing up a scheme to reorganize this activity on a national scale while taking into consideration these constraints, which are less contradictory than they may seem to be at first sight. Reviewing the age-old activity of animal husbandry in the light of non-violence is clearly based on the specific nature of Hindu traditions. However, it goes far beyond cultural or religious relativism, since it is also founded on universal ethical principles. 相似文献
30.
倭肯河着生硅藻群落结构及其与环境因子的关系 总被引:2,自引:0,他引:2
为了合理的评价倭肯河水生态健康状况,2018年8月(丰水期),调查了19个点位的着生藻类群落结构和水环境特征.使用Mcnaughton优势度分析、聚类分析和生态型分析3种方法研究了倭肯河着生藻类群落结构和清洁度,使用Spearman相关分析、除趋势对应分析和典范对应分析等方法研究了倭肯河着生硅藻群落和环境因子的响应关系.结果表明:倭肯河共鉴定出着生硅藻89种,物种丰富,不同采样点位之间生物多样性差异较大,Nitzschia palea等富营养指示种是倭肯河的优势种.聚类分析结果表明,倭肯河采样点位可分为3组,从组1到组3,优势种清洁度逐渐下降,低度需氧型、中腐-高度腐生型和极度富营养型硅藻比例逐渐上升.影响倭肯河着生硅藻群落结构的主要水环境因子为TN、DO和pH,其中DO和TN是组3着生硅藻群落的主要影响因子,pH是组2着生硅藻群落的主要影响因子.由此可见,除河流源头区域外,倭肯河水生态环境质量状况较差,着生硅藻群落可以有效的指示倭肯河水体营养状况和腐生状况. 相似文献