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Tamim Younos Fred W. Kaurish Terri Brown Raymond de Leon 《Journal of the American Water Resources Association》2001,37(2):327-334
ABSTRACT: Karst terrane provides a linkage between surface water and ground water regimes by means of caves, sinkholes and swallets, and sinking streams, and facilitates the inter‐watershed transfer of water and contaminants through these subsurface systems. The goal of this study was to develop procedures to identify the sources of degradation of a creek situated in a complex karst‐water system. The study approach consisted of using dye tracing technique to determine subsurface flow paths through the karst system, a water‐sampling network to identify and characterize pollution sources within the surface watershed and subsurface flow regime, and evaluation of analytical data for several water quality parameters. The results of this study provide an interesting perspective of water and contaminant movement in karst‐water systems and pinpoint the sources of stream contamination for a case study site in southwest Virginia where two springs supply water to a contaminated freshwater stream. 相似文献
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贵州省水资源承载力的空间地域差异 总被引:3,自引:1,他引:2
水资源承载力是一个国家或地区可持续发展过程中各种自然资源承载力的重要组成部分,对一个国家或地区综合的发展和发展规模有至关重要的影响。由于水资源承载力是涉及到人口、社会经济发展以及资源环境在内的复杂巨系统,通过利用综合多种因素的状态空间法,从综合、宏观的角度来描述研究区域现实的承载状况,并对其进行定量化表示和分析。以贵州省为例,根据其具体情况,选取了9个指标构成评价指标体系,并对各指标运用反映客观赋权的熵值法进行权重的确定,然后通过状态空间法求算出贵州省现实的水资源承载状态值及其理想状态值。计算结果表明,贵州省目前的水资源承载状况总体上处于超载状态,但不同的地区又有所差异,表现出一定的空间地域性。根据贵州省水资源承载的现状值与理想值的比较,把整个贵州省水资源承载力划分为3种类型区:严重超载区、满载区及可载区。计算结果符合贵州省水资源实际情况,对贵州省水资源的可持续利用具有一定的现实指导意义。 相似文献
636.
以祁连山区肃南县为例,分析了祁连山区山地草原荒漠化的现状及其危害,并结合历史,从自然和人为两方面探讨了草原荒漠化的成因。由于自然因素是形成草原荒漠化的基础,而人为因素才是其主导因素。所以本文主要就人为因素有针对性地提出了山地草原荒漠化的防治和生态环境重建的对策,即:加大资金引入,引进和推广新技术,减轻草原人高压力;实现合理用水,提高草原的数量和质量。 相似文献
637.
我国西部大开发中的沙漠化灾害防治研究 总被引:12,自引:4,他引:8
利用最新的沙漠化普查数据,分析了我国西部地区沙漠化灾害的现状,包括我国西部地区沙漠化灾害的面积与分布、沙漠化灾害的程度以及沙漠化灾害的主要危害等,探讨了在西部大开发中进行沙漠化灾害防治的原则,对策与措施等问题。 相似文献
638.
环江县异地扶贫开发与持续发展途径探讨 总被引:6,自引:1,他引:6
广泛分布的喀斯特地区是我国最贫困的地区之一,消除该类地区贫困的主要措施是开展异地扶贫开发。本文从异地扶贫开发与持续发展的角度出发,阐述了环江县异地扶贫开发的现状及其存在的问题,提出了异地扶贫开发与持续发展的模式、途径和战略。 相似文献
639.
Ross C 《Environmental monitoring and assessment》2004,99(1-3):267-274
Loss of vegetation production in arid lands has been difficult to remediate and has signifi- cant economic impacts on human
populations. Restoration efforts based on non-local materials and large-scale mechanization have not been capable of efficiently
reversing the trend of environmental degradation. The use of traditional knowledge and simplified methods of seed harvesting,
storing, marketing and soil preparation have proven that regeneration of native species and efficient land reclamation is
possible in areas that have traditionally been considered degraded beyond redemption. This paper describes a method of land
reclamation that combines tradition and simple mechanics that can be applied in all arid areas that face desertification.
Because the work builds on cultural practices long used in non-industrialized societies, it is particularly adapted to rural
areas. The methods described have the potential to open new low-tech economic opportunities to all segments of local non-urban
populations while combating desertification and creating a more ecologically sound environment. 相似文献
640.
Community Production Practices and Desertification in the Sahelo-Sudanian Region of Cameroon at the Turn of the Millennium 总被引:2,自引:0,他引:2
Pamo ET 《Environmental monitoring and assessment》2004,99(1-3):197-210
The Sahelo-Sudanian region of Cameroon extends over 10 million hectares. Varied flora and soil types, a complex mosaic of
vegetation and plant communities and a diversified wild animal population are the major natural resources of this region.
Desertification in the region can be related to two major known causes: a. short or long-term drought due to short-term or
long-term climatic trends toward aridity; b. human activities which degrade the biological environment. Globally, humans generally
have less effect on desertification than climatic change in the short run. The only strategy to fight against this situation
particularly in the developing countries is to withdraw populations from the areas and to settle them elsewhere. However,
most local or regional desertification processes in general, and in the Sahelo-Sudanian region in particular, are due to the
misuse or unsound exploitation of natural resources by humans and their animals. Often, comprehension of the complexity of
even small interactions between parameters affecting our local environment remains limited. Poor economic assessments of the
long-term benefits of proper natural resource conservation and management increase the extent of the exploitation, in turn
increasing the degradation process. Yet ecologically sound management of natural resources integrating indigenous knowledge
and basic population interest and concern can secure restoration in several areas and sustained productivity of Sahelo-Sudanian
lands. 相似文献