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631.
我国钢铁工业废水治理及其发展趋势   总被引:1,自引:0,他引:1  
我国水资源人均拥有量仅为世界人均拥有量的四分之一,而且降水在时空分布上很不均衡。这一现实,决定了节省水资源,保护水环境是我国一项长期的战略任务。文章概要地叙述了钢铁工业废水治理及其发展过程。作者认为,要从根本上解决钢铁工业废水对水环境的污染与破坏,必须采取综合防治措施,并把整套循环用水技术引入生产工艺过程,使废水与污染物都作为资源加以回收,并实现循环利用。上述过程的实质,是模拟大自然生物圈循环运行  相似文献   
632.
耕地资源是国土资源的精化所在,耕地资源的合理利用与否,严重影响和制约着四川整个国民经济和社会的发展,以及人民生活水平的提高。本文立足于四川耕地现状,全面分析了四川耕地资源存在的问题及开发利用前景,从战略高度提出了相应的对策和措施。  相似文献   
633.
The National Forest Management Act and National Environmental Policy Act require the use of an interdisciplinary team (ID team) to do integrated resource planning for the National Forests and the concurrent environmental analysis. A survey sent to all National Forest planning officers (82% response) reveals the composition of the ID teams used in integrated resource and land management planning. More than half the National Forests ID teams met NEPA and NFMA compositional requirements. National Forest planners recount their experiences with these ID teams. Despite frustrations with many aspects of the ID teams, the planners strongly support the idea that ID teams are an important part of the land-use planning process and think that their use leads to better National Forest integrated resource plans.  相似文献   
634.
ABSTRACT: The evolution of ground-water law in eight states in the Midwest (Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, and Wisconsin) is examined, and a review of transitions in ground-water doctrines is presented. Two underlying themes in changing ground-water management are communicated. First, ground-water law is evolving from private property rules of capture based on the absolute ownership doctrines to rules requiring conservation and sharing of ground water as a public resource. Second, in both courts and state legislatures, a proactive role of ground-water management is emerging, again, with an emphasis on sharing. Both of these trends are apparent in the Midwest. In the last decade midwestern states have (1) seen significant shifts in court decisions on ground-water use with greater recognition of the reciprocal or mutually dependent nature of ground-water rights, and (2) seen increased legislative development of comprehensive ground-water management statutes that emphasize the reciprocal liabilities of ground-water use. These trends are examined and ground-water management programs discussed for eight states in the Midwest.  相似文献   
635.
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   
636.
ABSTRACT: The Chubb/Bauman (Ch/B) method for making quantitative estimates of recreation potential for rivers is based on the 1968/ 69 Leopold method for quantitative assessment of the scenic beauty of rivers. Both use classifications of environmental variables as the database. Unlike the Leopold method, the classifications used in the Ch/B method consistently reflect human preferences. The Ch/B method collects information on 67 variables, and uses a computer program to produce estimates of potential for 16 common recreation activities. This critique evaluates selected concepts and procedures of the Ch/B method partly by comparison with other available methods of recreation resource inventory. It considers the validity and utility of numerical weighting of variables, the use of numbers derived from place in a classification, and the transformation process. The quantitative techniques of the method exhibit serious flaws. Much of the data produced by the method appears to be quantitative but in fact is not, and it does not produce truly quantitative estimates of recreation potential. Classifications of generalized geographic or environmental variables are shown to have serious defects as a basis for evaluation of recreational potential.  相似文献   
637.
Stream discharge of a watershed is affected and altered by climate and landcover changes. These effects vary depending on the magnitude and interaction of the changes, and need to be understood so that local water resource availability can be evaluated and socioeconomic development within a watershed be pursued and managed in a way sustainable with the local water resources. In this study, the landcover and climate change effects on stream discharge from the Jacks Fork River basin in the Ozark Highlands of the south-central United States were examined in three phases: site observation and data collection, model calibration and simulation, and model experiment and analysis. Major results of the study show that climate fluctuations between wet and dry extremes resulted in the same change of the basin discharge regardless of the landcover condition in the basin. On the other hand, under a specified climate condition landcover change from a grassland basin to a fully forested basin only resulted in about one half of the discharge change caused by the climate variation. Furthermore, when landcover change occurred simultaneously with climate variation, the basin discharge change amplified significantly and became larger than the combined discharge changes caused by the climate and landcover change alone, a result indicating a synergistic effect of landcover and climate change on basin discharge variability. Agricultural Research Division, University of Nebraska-Lincoln, Contribution Number 13437.Qi Hu: Corresponding author: Dr. Qi Hu, Climate and Bio-Atmospheric Sciences Group, School of Natural Resource Sciences, 237 L.W. Chase Hall, University of Nebraska-Lincoln, Lincoln, NE 68583-0728, USA. E-mail: qhu2@unl.edu.  相似文献   
638.
陈旭 《干旱环境监测》2004,18(2):106-108
利用美国陆地资源卫星TM5遥感信息,调查分析了鞍山市森林资源现状。结果表明,鞍山市共有森林资源466933.52hm^2,占全市土地面积的50.32%,其中灌木林占森林面积的81.11%。在此基础上,分析了存在的主要问题,并提出了恢复途径及生态建设模式。  相似文献   
639.
不同类型国家资源战略实施的启示及我国资源战略的选择   总被引:4,自引:0,他引:4  
资源战略是经济发展战略的重要组成部分。不同的国家有着不同的资源战略。本文通过对不同类型国家资源战略实施成败的分析,从中总结了3点有益的启示:①世界经济发展中的相互依赖越来越强;②资源战略的选择要符合本国的实际;③经济结构要多样化。本文还对我国高耗、低效、封闭式的资源战略的形成作了深入的分析,并提出了我国资源战略选择的4个主要方面:①多样化是中国资源战略的出发点;②充分利用国内资源,积极利用国外资源是我国资源战略的核心;③保护资源与环境是我国资源战略的重要组成部分;④建立资源节约型国民经济体系,是我国资源战略的目标。  相似文献   
640.
纳米磁流体及其在水资源保护中的应用前景   总被引:5,自引:1,他引:5  
在简要讨论水体油污染严重,保护水资源重要性的基础上,介绍基于纳米科学技术的新型材料纳米磁流体的制备、性质及其重要应用。重点讨论纳米磁流体在水体油污染治理中急待深入开展的研究内容及其在水资源保护中良好的应用前景。  相似文献   
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