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731.
辛醇生产废水处理技术 总被引:2,自引:0,他引:2
对国内外辛醇生产废水的处理方法作了介绍,并对较先进的酸化萃取法和厌氧生化-好氧生化-碳黑吸附法作了详细分析。 相似文献
732.
Studies of irrigation drainage in the Western United States have documented some of the effects of irrigating land without first understanding and then considering implications from the interdependent relationships of hydrology, geology, geochemistry, biology, climatology, land use and socio-economic issues. In studies completed in 26 areas, selenium is the trace element found most often at elevated concentrations in water, bottom material and biota. Boron, arsenic, mercury and pesticide residues have also been found at elevated levels in some areas. Bioaccumulation of constituents associated with irrigation drainage is common. As the world experiences an explosive population growth, particularly in poorer countries, demands for food production from marginal, submarginal and newly irrigated soils are likely to cause severe adverse environmental impacts from allocation of limited water resources and contamination from irrigation drainwater. Cultivated marginal land is highly susceptible to degradation from soil erosion, salinization and waterlogging, not withstanding release of contaminants from application of irrigation water. 相似文献
733.
本文论述了水土水流失对生态环境的影响和对农业生产的危害,阐明增强环境意识,加强水土保持时防止生态恶化,是我国振兴农业的重要性与紧迫性的任务。 相似文献
734.
介绍清洁生产的概念及其产生的背景。针对江汉石油管理局的现状,提出了实施清洁生产的几点设想,以期尽快将清洁生产付诸实施的同时带来经济效益和环境效益。 相似文献
735.
天然放射性物质及环境问题 总被引:1,自引:0,他引:1
天然放射性物质(naturallyoccurringradioactivematerials,简称NORM)广泛存在于地层中,当石油或天然气从地下开采出来时,痕量的天然放射性核素如镭、氧等也随之采出,并分别集中于管道及设备的垢层或天然气加工装置的内壁薄膜上。文章在对外文资料调研的基础上,将NORM的有关知识、存在场所、对人体潜在的危害途径及有关辐射防护方法进行了介绍。 相似文献
736.
Interdisciplinary teams have been used in federal land planning and in the private sector to reach consensus on the environmental impact of management. When a large data base is constructed, verifiability of the accuracy of the coded estimates and the underlying assumptions becomes a problem. A mechanism is provided by the use of a linear statistical model to evaluate production coefficients in terms of errors in coding and underlying assumptions. The technique can be used to evaluate other intuitive models depicting natural resource production in relation to prescribed variables, such as site factors or secondary succession. 相似文献
737.
Effects of cattle grazing and haying on wildlife conservation at National Wildlife Refuges in the United States 总被引:1,自引:0,他引:1
Beverly I. Strassmann 《Environmental management》1987,11(1):35-44
The National Wildlife Refuge System is perhaps the most important system of federal lands for protecting wildlife in the United States. Only at refuges has wildlife conservation been legislated to have higher priority than either recreational or commercial activities. Presently, private ranchers and farmers graze cattle on 981,954 ha and harvest hay on 12,021 ha at 123 National Wildlife Refuges. US Fish and Wildlife Service policy is to permit these uses primarily when needed to benefit refuge wildlife. To evaluate the success of this policy, I surveyed grassland management practices at the 123 refuges. The survey results indicate that in fiscal year 1980 there were 374,849 animal unit months (AUMs) of cattle grazing, or 41% more than was reported by the Fish and Wildlife Service. According to managers' opinions, 86 species of wildlife are positively affected and 82 are negatively affected by refuge cattle grazing or haying. However, quantitative field studies of the effect of cattle grazing and haying on wildlife coupled with the survey data on how refuge programs are implemented suggest that these activities are impeding the goal of wildlife conservation. Particular management problems uncovered by the survey include overgrazing of riparian habitats, wildlife mortality due to collisions with cattle fences, and mowing of migratory bird habitat during the breeding season. Managers reported that they spend $919,740 administering cattle grazing and haying; thus refuge grazing and haying programs are also expensive. At any single refuge these uses occupy up to 50% of refuge funds and 55% of staff time. In light of these results, prescribed burning may be a better wildlife management option than is either cattle grazing or haying. 相似文献
738.
Oettlé N Arendse A Koelle B Van der Poll A 《Environmental monitoring and assessment》2004,99(1-3):115-125
Community knowledge exchanges have played a key role in developmental processes in the Suid Bokkeveld community of South Africa.
Two exchange visits were undertaken with the support of the Department of Agriculture and an NGO, the Environmental Monitoring
Group, which have led to local economic development and enhanced capacity to manage natural resources in a sustainable manner.
These pilot projects were undertaken within the framework of the Community Exchange and Training Programme of the Global Mechanism
of the United Nations Convention to Combat Desertification (UNCCD). The methodology applied included facilitation to develop
a community-based vision for development, in terms of which the community exchange process was designed. A Facilitation Team
of service providers conducted preparatory workshops, and identified potential partner communities. Two exchange visits were
carried out, one focused on Rooibos production and marketing, and the other on community-based eco-tourism. Following report-back
and planning workshops, emerging community-driven initiatives were supported through their formative stages. The initiatives
have not only resulted in enhanced livelihoods, but the methodology has also been applied widely in a number of different
contexts. 相似文献
739.
740.