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951.
以人均相对灾害救济强度为指标,利用EOF方法分析了1978~1994年我国农村救灾款发放的时空分异规律,发现其5种主要空间分布形式;在东部地区,1984年以前华北救灾强度较东北和江南相对偏大,以后则相反。 相似文献
952.
防灾减灾的基础研究及应用研究进展概况 总被引:4,自引:2,他引:4
人类社会是在对自然灾害的不断斗争中得到发展。近代由于全球人口的迅速增长和城市化程度的提高,自然灾害的损失也在急剧增加。防灾减灾是减轻灾害损失、保障社会可持续发展的系统工程。当前灾害监测技术、灾害的形成和发展规律、灾情评估方法、灾害管理及灾害对社会经济的影响等方面的基础研究及应用研究已有了不小的进展。本文概括地介绍了这些进展,并指出了防灾减灾工作中存在的一些问题及对策 相似文献
953.
1994/1995全球重大自然灾害的统计分析 总被引:1,自引:1,他引:1
1994/1995年是60年代以来全球自然灾害经济损失最大的两年。作者根据收集到的信息,对全球这两年的重大自然灾害的分布及灾情作了统计。结果表明,90年代全球重大自然灾害的经济和保险损失存在上升趋势。最后,对其成因进行了分析 相似文献
954.
Sergio Rinaldi Warren Sanderson Alessandra Gragnani 《Journal of environmental management》1996,48(4):357-373
Policies for the management of natural resources and the resources themselves interact to form complex systems. In this paper, we present a highly simplified model that can be used to study the general features of those systems. The model has three state variables, the abundance of the resource, environmental pollution, and the capital devoted to pollution control. We analyse it graphically using the singular perturbation approach. Two modes of behavior are possible; stationary and cyclic. When the abundance of the resources varies cyclically, the length of the period of resource scarcity depends on population size, economic activity, pollution per unit of output, and policy constraints. We distinguish between two classes of policies, one in which decision-makers base their investments in pollution control capital on the abundance of the resource, and another in which those decisions depend on the amount of pollution. We show that policies based on the observation of pollution are safer than those based on resource abundance, because in the latter case, small changes in policy variables can lead much more easily to a collapse of the resource. Increases in population size, even when accompanied by an equiproportional increase in the pollution control budget can lead to a change from stationary to cyclic behavior, especially where policies are based on resource abundance. 相似文献
955.
As a result of the '16-year drought' that Burkina Faso experienced from the late 1970s to the mid-1980s, there has been significant
movement of people from the north of the country to the south. The large numbers of people that were displaced as a result
of this natural disaster put pressure on the production systems of the south and caused concern amongst development organisations
that environmental degradation would follow. Through a 2-year research period, using participatory approaches, it was found
that despite a doubling of the population and the introduction of foreign production systems, the process of communal land
control has significantly limited environmental degradation. This paper explains how customary law has controlled the settlement
of immigrants (the Mossi and Fulani) and how it has overseen land allocation in three villages. The conclusions of the study
indicate that, firstly, the customary law mechanisms in the three villages are effective in addressing communal resource use
and, secondly, there is an evolution in customary law systems as they respond to local change.
Received: 24 February 1999 · Accepted: 15 May 1999 相似文献
956.
匡玉芳 《长江流域资源与环境》1999,8(1):63-68
大麦是世界四大谷类作物之一,以适应性强、抗塑性强、抗逆性好、用途广而在世界各大洲广为种植。二次世界大战后,随着经济发展,大麦产量由60年代的9970.0万t增加到1994年的15872.8万T,长江 中游历来是我国大麦的主要种植之一,随着我国经济的发展,大麦生产经况愈下,成为我国进口量最大的农产品之一,其种植面积由1961年77.927万hm^2降为1995年的8.348万hm^2,与世界经济越发 相似文献
957.
资源代际管理与可持续发展 总被引:17,自引:0,他引:17
代际均衡发展是可持续发展战略的重要方面,代际均衡发展的物质基础是代际财富均衡。自然资源是代际财富均衡分配的主要内容,需要进行资源代际管理来保证可持续发展战略的实现。 相似文献
958.
可再生能源资源评价体系与方法 总被引:8,自引:0,他引:8
本文根据可再生能源资源的特性以及与技术、市场之间的内在联系,构建了可再生能源的资源评价体系,分析了资源量、生产率、生产经济性及不确定性分析等各环节中的具体评价方法和指标框架,并提出了最小和最大经济获利开发量以度量资源生产的经济性潜力 相似文献
959.
Donald N. Jeffs R. Peter Dennis 《Journal of the American Water Resources Association》1973,9(1):41-48
ABSTRACT. Most water takings in Ontario in excess of 10,000 gallons per day for purposes other than domestic, farm, or fire fighting require authorization by permit by the Ontario Ministry of the Environment. The legislation imposes control beyond that under common law, but does not remove common-law obligations. Permits may not be assigned without the Ministry's consent and do not create property rights in water. Permits to take ground-water require permittees to ensure that sufficient water is made available for the needs of prior users who suffer serious water-supply interference due to the taking, or to reduce the rate and amount of taking. Permits to take surface water require permittees to maintain sufficient downstream flow to protect downstream uses of water and natural functions of streams. Specific permit requirements for city wells in the rural Hunsburger Creek basin protect existing well supplies and require maintenance of streamflow for pond levels and fish. Tobacco irrigation in the Big Creek basin reduced streamflow significantly and requires development of more detailed water-management plans for years of extreme demand. Ontario's permit program serves to resolve water-use conflicts, furnishes information on use and provides one means for implementing management plans. 相似文献
960.
George E. Radosevich Evan C. Vlachos Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1973,9(2):352-359
ABSTRACT Whether the goal is minimizing water quality degradation in receiving streams or maximizing agricultural production on existing croplands; the solutions are identical - improved water management practices. Technology has succeeded in developing feasible solutions to improving irrigation water management, but the law has been slow to encourage or direct implementation. The villain of the western United States water problem is the property right concept of the appropriation doctrine. Improving water management also implies organizational improvements. Also, the so-called “human factor” involves questions of inefficiency and ineffectiveness, that when examined under the criteria of efficacy, may dictate a policy of continuing present practices in certain localities or regions with little technological intervention. The present effort for improving water quality management implies, therefore, a manyfold attack aimed at increasing project irrigation efficiency and effectiveness, under the larger rubric of efficacy and the achievement of larger social goals. 相似文献