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741.
尽管人类对温室效应和全球变化的认识还是很不充分的,但是继续拖延不采取措施是危险的,采取对抗温室效应和全球变化的措施是行不通的。只有在继续进行全球性科学研究的同时,积极寻求适应一定程度全球变化的措施,并立即着手减少温室气体的排放才是唯一明智的态度。化石能源是人类社会生存和发展的基础,既使用化石能源,又不排放二氧化碳是不可能是。首要的任务是减少化石能源的使用。 相似文献
742.
泥石流危险范围的模型实验预测法 总被引:6,自引:1,他引:6
泥石流危险范围的模型实验预测旨在确定一次泥石流可能堆积泛滥的最大范围.通过泥石流不同冲出量、堆积区坡度和容重的31次模型实验,获取了泥石流堆积面积.最大堆积长度、宽度和厚度的实验数据.采用量纲分析方法,建立了一次泥石流危险范围的预测模型,并由实验资料确定了模型的修正系数.在云南和甘肃的应用实践表明,预测模型精度高,适用范围广,可在我国泥石流危险范围预测预报中使用. 相似文献
743.
Creg S. Bishop Glen T. Broach Wendell H. Hester Vincent A. Sikora 《Journal of the American Water Resources Association》1982,18(2):189-195
ABSTRACT: The importance of water conservation was emphasized by a proposed National Water Policy which was established during the previous Carter Administration. This policy stressed water conservation on a national scale. Such a policy sought to apply one program to all water resources problems. Before implementation of this or another such policy, consideration must be given to those vast areas of the country which in reality do not have a shortage of water. One of these areas is the French-Broad River basin in Tennessee. This report was formulated in an effort to describe both the positive and negative effects of water policies which would bring about either a 10 percent or 30 percent reduction in water usage in this basically water rich area. The parameters used in the evaluation included selected economic, sociological, legal, and environmental impacts. 相似文献
744.
William M. Park William L. Miller 《Journal of the American Water Resources Association》1982,18(1):89-94
ABSTRACT: There is a long standing hypothesis that overdevelopment has occurred in the nation's floodplains due to imperfect information about the potential flood hazard, an expectation of disaster relief and anticipation of future structural protection. This hypothesis is investigated with multiple regression analysis of data for a case study area. In particular the question of whether floodplain residential property values are fully discounted for expected flood damages is addressed by considering the impact of the National Flood Insurance Program on property values. The extent to which flooding risk perceptions are based on low cost information such as distance from and elevation above the river is also considered. Finally, implications for floodplain management policy are discussed. 相似文献
745.
John W. Duffield 《Journal of the American Water Resources Association》1980,16(2):226-234
ABSTRACT: This paper provides a critical analysis of the Bureau of Reclamation's Auburn-Folsom South project in California. While this massive $1.5 billion project is temporarily halted for redesign for earthquake hazard, it is timely to examine its justification on economic grounds. The key finding is that several major benefit categories, irrigation and recreation, have been grossly overstated. In addition, the Bureau failed entirely to estimate the cost of use on the free-flowing American River, or a probability-weighted estimate of catastrophic loss. Revised estimates indicate that the project is not economically justified. In addition, the project has unattractive distributive effects. The implications of this case study for current revisions in U.S. water policy are explored. The Auburn study basically provides support for the U.S. Water Resource Council's draft manual of procedures for evaluating federal water resource projects. 相似文献
746.
Robert C. Waters 《Journal of the American Water Resources Association》1980,16(2):256-260
ABSTRACT: Federal spending on water resource development projects exceeds $10 billion annually. This paper examines the economic theory and practice on which the Federal water resource development plans are based. Existing theoretical and applied problems result in overinvestment. These include 1) no standard of value for the tradeoff of environmental objectives with economic objectives; 2) benefits based on “willingness to pay,” but beneficiaries pay only a fraction of a project's costs; 3) beneficiaries “shop around” among program purposes in order to reduce their commitments; and 4) benefit/cost (B/C) analyses are based on a discount rate, which is consistently below the Federal borrowing rate. Furthermore, the Government Accounting Office (GAO) frequently finds that the agency regulations are inadequate and result in inconsistent and questionable benefit computations. The President has proposed a series of water policy reforms, to reduce some of the apparent overinvestment in water resource development, but fundmental corrective action rests with the members of Congress. 相似文献
747.
Thomas M. Bonnicksen 《Environmental management》1981,5(6):521-529
A cross-impact simulation computer language, UW-KSIM, is presented as a potentially useful technique for assessing the consequences of resource policies. Cross-impact simulation is used to estimate trends in a set of variables that result from interactions produced from hypothesized relationships among the members of the set. This technique is illustrated with an example that simulates the likely impacts of a 20-year rotation burn policy in southern California's brushland watersheds and that compares the results to a simulated representation of the observed effects of the fire-exclusion policy. Simulated losses under the fire-exclusion policy were up to 300% higher than those produced by the rotation burn policy. Similarly, the simulated average area burned per year was reduced from 5.6% of the study area under the fire-exclusion policy to 2% of the study area under the rotation burn policy. A corresponding reduction in simulated appropriations for fighting wildfires was also demonstrated. 相似文献
748.
David J. Schaeffer Konanur G. Janardan Harold W. Kerster 《Environmental management》1981,5(6):515-520
The linear dose-response model is considered a conservative, nonthreshold relationship. This is based on a confusion between the sufficient condition (that is, zero slope at zero dose) and the necessary condition (that is, response distinguishable from zero). Once the threshold is properly defined, it is shown that the linear model predicts thresholds for radiation data in good agreement with experimental results. 相似文献
749.
Lawrence F. Keller Craig G. Heatwole James W. Weber 《Journal of the American Water Resources Association》1981,17(4):647-654
: This article examines the willingness and capacity of local districts to control ground water mining of the Ogallala Aquifer in the High Plains. The questions of willingness and capacity were approached through extensive field interviews and a survey of all district board members and managers. The analysis focuses on the policy alternatives board members and managers perceive and how they evaluate these alternatives. Methodologically, the study utilized factor analysis of responses rating the desirability of various policy alternatives to ascertain what alternatives were perceived by the sample. Then the sample's preferences for each of the identified factors were calculated. The results demonstrate that the sample of those who must regulate if ground water mining is to be controlled at the substate level are not oriented to regulatory policies and therefore lack the willingness to deal with ground water mining. 相似文献
750.
Theodore M. Schad 《Journal of the American Water Resources Association》1978,14(2):302-312
ABSTRACT: In 1973 the National Water Commission concluded its five-year study of national water policy by issuing a massive report containing over 200 recommendations for improvements in the way the Nation deals with its water resources. The Carter Administration is now engaged in another water policy review which incorporates many of the policies espoused by the National Water Commission. In this paper, presented at the 13th American Water Resources Conference in Tucson in November of 1977, the author describes the work of the National Water Commission and the actions taken on its recommendations. 相似文献