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The small-rodent populations of five collective gardens have been studied. The example of one of the populations has been used to monitor the annual cycle of population size. The species composition and animal number depends on the biotope, climatic conditions, and the anthropogenic load. The ratios between species in the gardens and neighboring biotopes differ from each other, with different species being dominant. It is assumed that small mammals use garden plots as refugia. 相似文献
174.
Yu. A. Maklyuk A. M. Maksimenko S. P. Gashchak M. D. Bondarkov I. V. Chizhevskii 《Russian Journal of Ecology》2007,38(3):181-189
Between 1986 and 1994, a decrease in nonalimentary 90Sr and 137Cs intake and changes in the accessibility of radionuclides in the soil-plant link of their cycle resulted in a 10-to 100-fold decrease in their specific activity (SA) in the bodies of small mammals inhabiting the Chernobyl zone, and a similar decrease was observed in the radionuclide transition factor (TF) in the soil-animal chain. Between 1995 and 2005, no consistent increase or decrease in SA or TF could be revealed against the background of a combined effect of different physicochemical and ecological factors. It is suggested that subsequent changes in the level of radioactive contamination of small mammals will generally reflect only the dynamics of physical 90Sr and 137Cs decay, but, nevertheless, seasonal and local variations in this level will be significant. 相似文献
175.
The Economic and Environmental Outcomes of Microfinance Projects: An Indian Case Study 总被引:1,自引:0,他引:1
Microfinance projects now seek to achieve improvement in environmental quality in addition to poverty alleviation. Achievement
of these goals may depend upon the economic and environmental impact of microfinance businesses. This study is a quantitative
analysis of these outcomes for Ecodevelopment, an Indian microfinance project, which aims to prevent forest degradation by
poverty alleviation. The study divides businesses into perishable goods, non-perishable goods, simple skills, and special
skills and measures their economic outcome by two indicators, repayment percentage and continuity of businesses. The study
examines the effect of loan amount on the economic outcome of businesses. To quantify the environmental outcome, it analyzes
the use of firewood or fodder and release of pollutants by businesses. The results show that loan amount does not affect the
economic outcome, special skills have best performance, and skills cause less pressure on forest resources. These results
suggest the need for development of knowledge-intensive skills, involvement of institutions in the operations of business,
and inclusive policies for protected area management. 相似文献
176.
旅游小镇建设将有力促进云南省城市化水平的提高,促进云南旅游业提质增效,促进农村发展中一系列深层次矛盾的解决。云南省旅游小镇建设应坚持政府引导、市场导向、突出特色、强化主题、尊重自然、延续文脉、资源整合、塑造品牌、功能完善、设施配套、保护优先、持续发展的原则,妥善解决规划编制、资金筹集、管理体制等关键问题。 相似文献
177.
大春河小流域水土保持综合治理成效显著,是一个高标准、大规模、好效益的集综合防治、科技推广、试验示范于一体的"精品小流域",为水土流失综合治理与农业产业结构调整起了很好的示范作用。 相似文献
178.
V. N. Pozolotina 《Russian Journal of Ecology》2001,32(2):102-109
Local dandelion (Taraxacum officinales.l.) populations were studied in the areas of the Eastern Ural Radioactive Trace and the floodplain of the Techa River in its upper reaches. In impact plots, the density of soil and plant cover contamination with 90Sr and 137Cs exceeded the background level by factors of 13–440 and 2–500, respectively; the radiation load exceeded the background level by factors of 1.5 to 45. The seed progeny of plants from these plots was characterized by a high proportion of abnormal seedlings and an increased level of chromosome aberrations in meristem cells. In some years, variation in the seedling viability, growth rate, and developmental rate in these plots exceeded the reaction norm of plants from the background plot, demonstrating both stimulation and inhibition of growth processes. The response of seeds to acute irradiation at high challenging doses varied depending on the level of background radiation in the plots. 相似文献
179.
黄土丘陵区小流域生态经济系统健康评价 总被引:48,自引:1,他引:47
建立健康的流域生态系统是恢复退化的生态系统、实现黄土高原山川秀美的目标。论文以安塞纸坊沟小流域为对象,利用层次分析法,选取林草覆盖度、基本农田面积、土壤抗冲性、土壤有机质含量、农业产投比、粮食单产、人均纯收入和综合治理减沙效率等反映流域生态经济系统功能评价指标,定量分析了黄土丘陵区安塞纸坊沟小流域进行水土保持型生态农业的建设中生态系统恢复的过程。研究表明,该小流域经过近20年治理,经历了起始恢复、稳定发展阶段,开始进入良性循环。其健康指数由1985年的0.178增加到1999年的0.707。研究中首次引入土壤抗冲性和有机质指标,并在评价中对生态系统恢复不同阶段给予各指标不同权重值,对方法进行了改进。 相似文献
180.
Weslynne Ashton Suzana Russell Elizabeth Futch 《Journal of Environmental Planning and Management》2017,60(12):2133-2149
Manufacturers around the world green their businesses for a variety of reasons, including competitiveness, social responsibility, and external stakeholder pressure. However, small and medium enterprises (SMEs) are thought to lag behind larger ones in the adoption of green business practices. This paper explores the motivations for US Midwestern SMEs adopting a variety of green business practices, using a survey of 59 SMEs in the tool and die manufacturing industry. The majority of firms appear to be internally motivated to implement green practices – driven primarily by cost and competitiveness concerns, more than by social responsibility concerns. External coercive pressure from government or customers does not appear to be a significant motivation for these SMEs. However, informal pressure through government incentives and support programs, as well as mimetic pressure through peer learning via industry associations, appear to be more effective in helping these SMEs to further ‘go green.’ 相似文献