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991.
Using the example of bats inhabiting the Volga region, the cases in which the anthropogenic factor creates favorable conditions for these animals or significantly reduces their diversity of their fauna are considered. In this context, an opinion concerning the approaches to the conservation of bats is formulated. 相似文献
992.
Jeffrey Barber 《Environment, Development and Sustainability》2003,5(1-2):63-93
At the World Summit on Sustainable Development (WSSD), world leaders agreed that eliminating unsustainable production and consumption is one of the three overriding objectives of sustainable development. Achieving that objective should have been a major priority for the WSSD Plan of Implementation. Increases in consumption and production over the past decade were largely responsible for the worsening environmental and social trends. Unfortunately, the negotiators of the Plan paid insufficient attention to the lessons from 10 years of discussions about the concepts, the available policies and tools and their effectiveness, the impacts of those policies on developing countries, and the political commitment of countries in an era of globalization. Despite a promising proposal for a new ten-year work programme aimed at bridging the gap implementing the Agenda 21 commitments from Rio, Summit negotiators produced barely more than a muted echo of recommendations from the past which have yet to be taken seriously enough by the world's leaders in a comprehensive intergovernmental strategy. In the ten-year review of progress to achieve sustainable production and consumption (SPAC), governments quickly skipped past the critical work of examining why things are getting worse, avoiding the task of identifying the obstacles (which in some cases were themselves) and in turn avoiding the commitment to time-bound measurable targets. If nothing else, the WSSD demonstrated that a global strategy to achieve SPAC will come not from a UN consensus of world leaders but from a strategic alliance of responsible governments, civil society and others with a vision beyond the next election cycle. 相似文献
993.
The main goals of this paper are to (1) highlight the need for sustainable development as a means to conserve natural resources and the environment, which often represent the basis for tourism development, (2) illustrate the importance of assessing tourists' preferences when designing programs and policies central to the sustainable development of a tourism area, and (3) study tourists' interests in sustainable development. With these goals in mind, 180 tourists from Europe, Latin America, and North America were interviewed as they were leaving the resort region of Punta Cana in the Dominican Republic. The main factors that they considered when deciding where to go on a beach vacation were evaluated, as well as their preferences regarding four programs designed to improve recreational and environmental management of the area. Preferences by tourists were elicited both in monetary and non-monetary terms. This paper reports the non-monetary analysis of the data. The results indicate that clean ocean water and beaches, quality of services, and price are the most important factors considered by the respondents before deciding to come to Punta Cana. It was not possible to obtain reliable responses on how tourists perceived the four programs contributing to the sustainable development of Punta Cana. Nevertheless, they expressed high interest and willingness to pay for two of these programs: the outdoor aquarium and the Water Management Program. The results reported in this paper show how important it is to elicit tourists' preferences of programs central to the sustainable development of tourism areas since these preferences can drive managers' development decisions in more sustainable directions. 相似文献
994.
Carlos Pomareda 《Journal of the American Water Resources Association》1978,14(1):24-34
ABSTRACT: Economic analysis of irrigation production functions is discussed using linear programming. The method provides advantages over the partial one-crop type of analyses because it captures intercrop tradeoffs in water and land use in response to economic policies or changes in water supply. A numerical example is used. 相似文献
995.
A. Bhagyalakshmi S. Venkata Reddy R. Ramamurthi P. S. Reddy 《Chemistry and Ecology》1995,11(2):97-104
Toxicity of an organochloride insecticide, hexachlorocyclohexane (HCH) on the alterations in the growth and silk qualities of silkworm, Bombyx mori L were investigated. HCH yielded higher growth constants (K), indicating impairment of growth of silkworms and silk gland. the decrement in fibroin content is significant. HCH treatment also resulted in considerable reduction in the cocoon, pupal and shell weights, survival and emergence of pupae and number of eggs laid and deterioration in quality and quantity of silk thread. 相似文献
996.
论述长江流域发展粮食生产的重要性,分析粮食资源分布,生产状况,生产结构和地域差异,指出粮食合理布局的方向,提出以粮食集中产区为重点,建设长江流域粮食生产专业化地并以建设商品粮基地为建带突破口。 相似文献
997.
中日韩循环经济政策比较研究 总被引:6,自引:0,他引:6
在中国经济迅猛发展的同时,投资主导型的经济模式中环境保护要素的缺失导致我国工业化发展旱、中期的资源、能源约束、效率低下和浪费严重。在我国实施循环经济刻不容缓。循环经济政策是依据不同的社会、经济和环境条件而制定的。由于历史的原因,中日韩三国在地缘关系、政治传统、风俗习惯、文化教育等内在制度和外在制度彼此趋同,反映在循环经济政策的制定、执行上也有某些相似的地方。对三国循环经济的历史和现状进行比较研究,得出有益于我国的经验,无疑具有很重大的现实意义。采用制度变迁的基本理论作为指导,运用历史研究法、调查研究法等方法进行研究,对中日韩循环经济政策演变的历程进行系统梳理和比较,深入全面地考量其指导思想和举措的选择动机,系统广泛地从多方面研究中日韩循环经济政策。并将三者加以比较,以得出对我国循环经济的发展具有较强借鉴意义的经验,更好地推进循环经济在我国的发展。 相似文献
998.
本文简述了清洁生产的概念与国外清洁生产的概况,评述了国内工业生产的现状及推行清洁生产的潜力和前景,并提出了一些有益建议。 相似文献
999.
清洁生产与企业组织创新 总被引:1,自引:0,他引:1
清洁生产是人类社会可持续发展的主要途径之一,已越来越受到各国政府与企业的重视。本文从企业文化、组织结构及企业战略等方面阐述了清洁生产对企业组织的影响。 相似文献
1000.
Fresh water, a fundamental element of all estuarine ecosystems, is South Africa’s most limited natural resource. Recent projections
indicate that by the year 2020 the country will be utilizing all its exploitable freshwater sources. Steeply increasing demands
by a rapidly growing population on this limited commodity have already resulted in a severe reduction of water supplies to
natural users such as estuaries-this trend is predicted to increase in the future. Concurrent with excesive water abstraction,
poor land husbandry (e.g. soil erosion) in many catchment basins and pollution (e.g. salinization) in return flows have led
to a serious deterioration in water quality. In contrast, a review of estuarine responses to varying flow regimes stresses
the strong dependence of local systems on riverine fresh water inputs of adequate quantity and quality. Freshwater dependence
is i.a. expressed in: flooding events that scour accumulated sediments, riverine nutrient input to drive estuarine phyto-
and zooplankton production, axial salinity gradients that increase habitat and species diversity, and maintenance of open
tidal inlets that prevent salinity and temperature extremes and facilitate larval exchange, fish migrations and tidal flushing
of salt marshes. Thus, estuarine conservation will have to encompass management of rivers and watersheds and play an increasingly
political role in decision processes concerning water allocations among ‘human’ and ‘natural’ users. 相似文献