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481.
Cattle production has the potential of being an important component of sustainable agriculture globally. The ability to transform feed not suitable for humans into high-quality food will be of great importance in the long-term for feeding a growing population. Other aspects such as preservation of landscape values and maintenance of rural communities are highly appreciated values, especially in the industrialized part of the world.To exploit the sustainable potential of cattle production systems, problems of pollution (such as ozone destruction, acid rain, and nitrate leaching) and of health and welfare, which are associated with cattle production, are critically reviewed. The possibilities of integrating cattle production with other types of production are evaluated. Cattle can be used for single purposes such as dairy, beef, and draught, but dairy cows can also be used for restricted suckling combining dairy and beef production. In addition a mixture of species makes grazing more efficient, and a combination of cattle and mixed cropping can increase resource efficiency.The possibilities of using organic cattle production systems as prototypes of sustainable cattle production systems are explored. The effects of production constraints which are applied in organic farming systems are studied. The redirection of values and activities in agriculture is a challenge to cattle production research and to traditional research methodologies.  相似文献   
482.
Sustainability is a concept that has been widely embraced both politically and intellectually but has not been addressed in terms of practical application. In most resource sectors, the features of a sustainable future remain unclear and there are few examples that give practical expression to sustainability. This is especially true in the case of water resources management which has been conspicuous in its absence from the majority of the literature. This paper attempts to address this deficiency on two counts. First, it provides a discussion of sustainability and the application of the concept to the management of water resources. Second, the paper illustrates how the concept can be utilized for the management and planning of urban stormwater. The paper concludes by offering research opportunities to investigate the feasibility of adopting natural channel design and artificial wetlands for sustainable stormwater management.  相似文献   
483.
Critics of my book, Sustainability, have raised many objections which are addressed. In general, I emphasize that the book is an integrative work; it must be long and complex beause it attempts a comprehensive treatment of problems of communication, of evaluation, and of management action in environmental discourse. I explain that I depend upon the pragmatists and on work in the pragmatics of language because the current language of environmental policy discourse is inadequate to allow deliberative processes that can reach consensus and cooperative actions. I revise my account of risk analysis somewhat, and defend my broad approach to the concept of sustainability. Finally, I discuss applications of my book to the current situation in environmental policy discourse.  相似文献   
484.
485.
Norton argues on pragmatic “Deweyan” grounds that we should cease to ask scientists for value neutral definitions of “sustainability,” developed independently of moral and social values, to guide our environmental policy making debates. “Sustainability,” like human “health,” is a normative concept from the start—one that cannot be meaningfully developed by scientists or economists without input by all the stake holders affected. While I endorse Norton’s approach, I question his apparent presumption that concern for sustainability for the future is at odds with and ought to trump concern for enhancement in the present of public opportunities to access the goods nature represents. I argue that the two are not separable in practice. I argue for Passmore’s position that unless we take care to enhance equitable access to the good and services nature represents in the present, we cannot succeed in promoting sustainability for future generations.  相似文献   
486.
Abstract: The population of Collier and Lee Counties in southwestern Florida has increased 11‐fold from 1960 to 2004 with a concomitant increase in freshwater demand. Water levels and salinity within the water table aquifer over the past two to three decades have generally been stable, with more monitoring wells showing statistically significant temporal increases in water level than decreases. Residential development has had a neutral impact on the water table aquifer because the total annual evapotranspiration of residential communities is comparable to that of native vegetation and less than that of most agricultural land uses. Public water supply systems and private wells also result in net recharge to the water table aquifer with water produced from deeper aquifers. Confined freshwater aquifers have overall trends of decreasing water levels. However, with the exception of the mid‐Hawthorn aquifer, water levels in most areas recover to near background levels each summer wet season. Freshwater resources in humid subtropical areas, such as southwestern Florida, are relatively robust because of the great aquifer recharge potential from the excess of rainfall over ET during the wet season. Proper management can result in sustainable water resources.  相似文献   
487.
Animal welfare and the ethical issues it raises have been discussed intensively for a couple of decades. The emphasis has been on the direct effects of housing and husbandry, but more attention is now being given to problems originating in selective breeding. European attempts to adjust animal welfare legislation to deal with these problems have been largely unsuccessful, but the fact that selective breeding can introduce welfare problems continues to place an ethical responsibility on the animal breeding industry. Since breeding decisions are made centrally and, increasingly, internationally, strategic change is only likely to occur if it is embedded in an international agreement of some kind. The aim of this paper is to describe the key ethical issues facing animal breeding and assess the suggestion that the breeding industry itself can deal with ethical issues by means of an ethical code. Results from recent projects involving commercial breeding enterprises are presented.  相似文献   
488.
《中华人民共和国循环经济促进法》的颁布和实施,标志着我国经济发展进入了一个新的阶段。对政府职能提出了。些新的要求漫企业也将承担相应的社会责任。承担社会责任的能力也将成为企业核心竞争力的一部分。  相似文献   
489.
企业环境信息公开通过加强市场和公众等利益相关者对企业环境行为的激励作用,促进企业改善其环境绩效。文章以常熟市参与环境行为评级和信息公开的企业为研究对象,分析了企业参与信息公开后总体环境绩效及具体环境行为的变化情况。同时,基于企业微观数据,构建了企业环境绩效变化与环境行为历史评级结果的关系模型,分析企业对环境行为评级与公开的响应程度。结果表明:历史环境评级结果差、有外资投入的企业对环境信息公开更能产生积极的响应;不同规模和行业类型的企业的响应程度没有显著的差异。进一步的研究发现,历史评级结果较差的企业感受到最大的压力变化来源于政府部门的监察,而有外商投资的企业则明显感到来自下游企业和投资者的压力。  相似文献   
490.
The southern interior ecoprovince (SIE) of British Columbia, Canada represents the northernmost extent of the great western North American deserts, it is experiencing some of the nation's fastest economic and population growth making it one of Canada's most water‐stressed regions, and it includes two headwater basins of the transboundary (Canada‐US) Columbia River. Statistical trend analyses were performed on 90‐year regional indicator time series for annual conditions in observed temperature, precipitation, and streamflow reflecting the three major SIE river basins: the Thompson, and transboundary Okanagan and Similkameen. Results suggest that regional climate has grown warmer and wetter, but with little net impact on total water supply availability. The outcome might reflect mutual cancellation of increases in precipitation inputs vs. evapotranspiration losses. Conclusions appeared largely insensitive to low‐pass data filtering, Pacific Decadal Oscillation effects, or solar output variability. Ensemble historical global climate model runs over the same time interval support this absence of appreciable trend in regionally integrated annual runoff volume, but a possible mismatch in precipitation results suggests a direction for further study. Overall, while important changes in hydrologic timing and extremes are likely occurring here, there is limited evidence for a net change in overall water supply availability over the last century.  相似文献   
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