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971.
This paper analyses the extent to which the new Reagan mineral policy will encourage increased US production, substitution, recycling and conservation, domestic stock-piling and diversification of foreign supplies. Major inadequacies of the mineral policy are the transfer of responsibility for research and development from the government to the unprepared private sector, the lack of emphasis on short-term research and development in mineral processing technology, and the lack of coordination between minerals policy and national security and foreign policy. However, overall the policy is a positive step towards reducing the current US minerals supply vulnerability.  相似文献   
972.
The Cache River of southernmost Illinois is used as a case study for developing and demonstrating an approach to quantitatively link (1) national agricultural policy and global agricultural markets, (2) landowner's decisions on land use, (3) spatial patterns of land use at a watershed scale, and (4) hydrologic impacts, thus providing a basis to predict, under a certain set of circumstances, the environmental consequences of economic and political decisions made at larger spatial scales. The heart of the analysis is an estimation, using logistic regression, of the affect of crop prices and Conservation Reserve Program (CRP) rental rates on farmland owner's decisions whether to reenroll in the CRP or return to crop production. This analysis shows that reasonable ranges for crop prices (80%–150% of 1985–1995 values) and CRP rental rates (0–125% of 1985–1995 rates) result in a range of 3%–92% of CRP lands being returned to crop production, with crop prices having a slightly greater effect than CRP rental rates. Four crop price/CRP rental rate scenarios are used to display resulting land-use patterns, and their effect on sediment loads, a critical environmental quality parameter in this case, using the agricultural non point source (AGNPS) model. These scenarios demonstrate the importance of spatial pattern of land uses on hydrological and ecological processes within watersheds. The approach developed can be adapted for use by local governments and watershed associations whose goals are to improve watershed resources and environmental quality.  相似文献   
973.
Proactive Management of Air Quality   总被引:1,自引:0,他引:1  
Traditional air resource management systems have difficulty in addressing global issues, sustainable development, direct citizen participation, and integration with broad economic interests. As reactive management systems, they tend to be compliance-driven, static, and rigid. In contrast, proactive management systems are principle-driven, innovative, and flexible. Bridge scientists play a key role in supporting the transformation of raw data into wise action. Decision-makers need to integrate social values with knowledge about emissions, atmospheric processes, and potential environmental effects using the primary tools of measurements, monitoring, and modeling. The Alberta Clean Air Strategic Alliance, a unique partnership of governments, industry, and public interest groups formed in 1994, operates a comprehensive air management system that is capable of addressing air issues of greater complexity and uncertainty. Its success is measured by the satisfaction of its diverse stakeholders and by the number and scope of its initiatives.  相似文献   
974.
The presence of Whitethroats and their potential invertebrate prey in farmland trees and shrubs was investigated. The management of this vegetation by farmers, and their motivation for that management, was explored using participatory techniques. Whitethroats were associated with Guiera senegalensis, the shrub species which supports most caterpillars and spiders. Farmers reported declines in trees and shrubs since the 1950s, loss of fallow areas, declines in soil fertility and crop yields, and increases in the use of fire for clearing fields. Trees are valued by people for their cultural and medicinal uses and some species used by Whitethroats and other birds have potential for restoring soil fertility, although this was not recognised by farmers. More sustainable use of savanna farmland could have both agronomic and wider conservation benefits, and the provision of information that accommodates farmers' cultural and economic incentives could benefit both farmers and wildlife.  相似文献   
975.
Human Population Numbers as a Function of Food Supply   总被引:1,自引:1,他引:0  
Human population growth has typically been seen as the primary causative factor of other ecologically destructive phenomena. Current human disease epidemics are explored as a function of population size. That human population growth is itself a phenomenon with clearly identifiable ecological/biological causes has been overlooked. Here, human population growth is discussed as being subject to the same dynamic processes as the population growth of other species. Contrary to the widely held belief that food production must be increased to feed the growing population, experimental and correlational data indicate that human population growth varies as a function of food availability. By increasing food production for humans, at the expense of other species, the biologically determined effect has been, and continues to be, an increase in the human population. Understanding the relationship between food increases and population increases is proposed as a necessary first step in addressing this global problem. Resistance to this perspective is briefly discussed in terms of cultural bias in science.  相似文献   
976.
以赭曲霉死菌丝体为载体,吸附红平红球菌(Rhodococcus erythropo lisNG0402)和白腐菌(Phanerochaete chrysosporiumM E-446)的混合物,用聚乙烯醇作包埋剂进行共固定化。用制备好的共固定化细胞处理增塑剂废水,连续运行19d的结果表明,共固定化处理增塑剂废水的效果远好于单一菌的效果。在pH7.0、溶解氧质量浓度3.0m g/L、水力停留时间25h的条件下,废水中苯酚、COD和色度的去除率连续15d达到了90%以上,对苯酚的去除能力为2.16kg/(m3.d)。  相似文献   
977.
谈庆 《环境工程》2005,23(6):90-92
在此提出了天车通过式捕集工艺方法。并在45t转炉的烟气治理上得到成功应用,为解决45t以下中小转炉的问题开辟了新的途径。  相似文献   
978.
不同产地的几种海藻中砷的形态和含量分析   总被引:9,自引:0,他引:9  
朱亚尔  李俊  李士敏 《环境化学》2005,24(4):478-480
采用干法消解和盐酸浸提处理、氢化物原子荧光光谱法对不同产地的几种海藻中的砷进行了形态和含量分析.结果表明,在实验浓度范围内,最低检出限达到0.147μg·1-1,线性相关系数0.9990以上,四种褐藻的精密度在0.74%-4.93%之间,回收率在91.64%-101.62%之间.四种褐藻的总砷和无机砷含量分别在16.58μg·g-1和5.104μg·g-1以上,其中羊栖菜的总砷和无机砷含量最高.  相似文献   
979.
武咸城际铁路在咸宁市上跨武广高速铁路,安全风险极大。论述了跨高速铁路桥梁基础承台防护桩的设计和施工,分析了防护桩设计的影响因素,确定了计算桩长。此外,从单桩承载力、桩基内力及基地应力三方面计算进行了安全性验证,确保了桥梁承台施工安全,对类似工程的基础安全防护有较好的借鉴作用。  相似文献   
980.
阐述了茶油加工工艺及生产流程,分析了茶油生产过程中的废水污染源、废气污染源、固废污染源和噪声污染源,结合国外内茶油生产加工和环保实践,针对性地提出了废水、废气、固废、噪声污染防治和资源化对策,分析了环境风险可信事故,并提出了环境风险防范措施,探讨了清洁生产合理化建议,为茶油生产企业的环境影响评价、工程治理和日常环境监管提供了依据。  相似文献   
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