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991.
Paul N. Wilson Teddy J. Goldammer James C. Wade 《Journal of the American Water Resources Association》1988,24(1):1-9
ABSTRACT: Urban wastewater can be a valuable source of water and plant nutrients for agricultural producers, particularly in arid regions. The scientific literature reveals cautious optimism concerning the biological, institutional, and economic viability of irrigating crops with secondary-treated effluent. A derived effluent demand function for agricultural producers near Tucson, Arizona, reveals a potential annual demand of 11,000 acre-feet under present price and proposed delivery system conditions. In this case, wastewater could be exchanged for ground water and both the urban and rural areas would gain. 相似文献
992.
比较了胶布热空气连续硫化废气的几种处理方法,认为焚烧法是最有效的处理方法,并对应用该法处理废气的工艺原理、主要设备、余热回收是焚烧过程中诮注意的事项作了较详尽的阐述。 相似文献
993.
将含有大量悬浮物的洗气箱废水进行初级沉降后,约3/4的废水返回洗气箱用作洗涤水,其余的与洗气塔废水混合进地沉降池去除悬浮物,上清液送至生物滤池进行生化处理去除含氰人合物其他有机物。生化出水经絮凝、澄清后回用于洗气箱和洗气塔实现了废水闭路循环。他 相似文献
994.
995.
电解法处理高含硫气田水 总被引:1,自引:0,他引:1
本文详细介绍了川南矿区含硫气田水电解法处理的试验情况,用自己研制的电解反应器对电解时间、pH值、电流密度等工艺条件进行了考察,提出了电解法处理含S~(2-)200mg/L的气田水的最佳工艺条件。试验结果表明:该方法是成功的,它可以使气田水中硫化物的脱除率达99%以上,达到国家排放标准(GB8978—88:S~(2-)<5mg/L)。该方法的主要特点是投加处理药剂少,操作简便,设备小型,占地面积小,特别适用于产水量不大的井站使用。 相似文献
996.
本文分析了江苏省近几十年来、特别是80年代以来冬季气温的变化特征,根据农业灾害发生的条件,讨论了“暖冬”对农业生产及农业灾害的影响,为农业生产部门和防灾抗灾部门决策提供科学依据. 相似文献
997.
A. L. Jensen 《Environmental management》1984,8(2):135-140
Conventional surplus production models indicate that destruction of fish populations by overfishing is difficult, if not impossible, but catastrophic declines in abundance of exploited populations are common. Surplus production models also do not predict large continuing fluctuations in yield, but large fluctuations in yield are common. Conventional surplus production models assume that fisheries do not impact the population's capacity to increase, but changes in age structure or a decrease in age-specific fecundity resulting from fishing can decrease the coefficient of increase. A surplus production model is developed in which fishing reduces the capacity of a population to increase; the model is applied to describe the fluctuations observed in yield of lake herring (Coregonus artedii) from the upper Great Lakes. The fisheries of the Great Lakes were decimated by the combined effects of heavy fishing and a changing environment. For some species, yield increased to high levels and then the fisheries collapsed; for other species, yield and effort fluctuated greatly. 相似文献
998.
Kennett SA 《Environmental management》2002,30(5):0595-0608
Biosphere greenhouse gas (GHG) management consists of preserving and enhancing terrestrial carbon pools and producing biomass
as a fossil fuel substitute. The discussion of this topic has focused primarily on carbon-accounting and project-level issues,
particularly relating to carbon sequestration as a source of emissions credits under the Kyoto Protocol. While international
consensus on these matters is needed, this paper argues that an important domestic policy agenda also deserves attention.
National policies for biosphere GHG management are necessary to bring about large-scale changes in land-use, forestry, and
agricultural practices and can address some of the technical and policy issues that have proven to be particularly problematic
from carbon-accounting and project-level perspectives. These policies should minimize land-use and resource-management conflicts,
account for collateral benefits, and ensure institutional compatibility with existing resource-management regimes. Issues
relating to project permanence, leakage, and transaction costs should also be addressed. A range of policy instruments should
be used and biosphere GHG management should be one component of an integrated approach to environmental and resource management.
Countries promoting biosphere GHG management as an important element of their climate change strategies should be developing
these domestic policies to complement international negotiations and to demonstrate that carbon sequestration and biomass
production can make an effective contribution to the stabilization of atmospheric GHG concentrations. 相似文献
999.
阐述了大冶有色金属公司安全生产标准化建设内容,安全生产标准制定准则,建设体系以及建设效果,为现代企业安全生产管理积累了经验,可供借鉴。 相似文献
1000.