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1.
The alpine musk deer (Moschus chrysogaster) is a key species of some terrestrial ecosystems, it has an important economic and conservative significance as a kind of medical animal in China. Due to the interaction between natural forces and human disturbance, the habitats of alpine musk deer are fragmented and isolated in different mountains and the populations are confronted with many problems of survival. In this paper, we discuss the impact of habitat fragmentation and isolation on alpine musk deer populations based on the investigation on the population densities and sizes and environmental factors in different reserves, as well as on the analysis of its ecological adaptability. We found that the alpine musk deer has strong ecological adaptability; the population development of alpine musk deer may benefit from the reduction of the forest area and even from the fragmentation and isolation of the habitat to a certain extent. However, deforestion should not be encouraged only for the alpine musk deer population, but should also be based on the overall consideration of biodiversity conservation.  相似文献   
2.
关于公路环境监理专业化问题   总被引:16,自引:0,他引:16  
根据公路项目的环境管理的现状和公路施工对环境的影响,结合公路环境监理试点工作的实践,提出建立专业化的环境监理队伍,专业化的组织形式,规范化的工作方法等。  相似文献   
3.
Due to assimilation of recycled CO2 from litter decomposition and photosynthetic changes in carbon fractionation at low light levels, the foliage at the base of a forest is often more depleted in13C compared to that exposed to the atmosphere in either the canopy or in open clearings. This is referred to as the canopy effect. African research has indicated that these habitat differences in foliar 13C can be substantial enough to affect the carbon isotope ratios of resident fauna. Previous work documenting a 30-year chronology on moose teeth from Isle Royale National Park indicated a progressive depletion in13C and suggested that this could be due to forest regrowth following extensive burning. The present study examined the assumption implicit in this hypothesis that foliar 13C varies between open and closed boreal forest sites. I found a marginal canopy effect of 2 13C difference between upper canopy and ground flora for a forest in northwestern Ontario and an average difference of 1.2 in under- and mid-story vegetation between closed forests and open clear-cuts. Because of these small differences, the utility of carbon isotope analysis in quantifying temporally integrated exploitation of deforested habitats will be low for northern boreal locations. In denser forests, such as those in the tropics or western North American where the canopy effect can be expected to be much greater, 13C analysis may still offer some promise for determining selection by wildlife of disturbed habitats.  相似文献   
4.
Concerns over the loss of biodiversity and ecosystem services in farmland have prompted the development of agri-environment policy measures aimed at reducing farming pressure and maintaining semi-natural habitats in farmed landscapes. However, further knowledge is needed to guarantee successful agri-environment measures implementation. The current study assessed the quantity and the quality of semi-natural habitats in farms across a gradient of farming intensities in two contrasting regions in Ireland. Policy protection seemed fundamental for semi-natural habitats preservation. Habitats not protected by agricultural policy relied on extensive farming and are in danger of disappearing if they are intensified or abandoned. Due to the lack of policy incentives for habitat quality, no correlations were found between farming intensity and share of semi-natural habitats with habitat quality. Therefore, extensive farming and retention of habitats alone may not reverse the decline of farmland quality and biodiverisity and, thus, measures incentivising the environmental quality may be more successful.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01344-6) contains supplementary material, which is available to authorized users.  相似文献   
5.
本文即围绕规划环境影响评价工作当中,有关生境评价的几点问题展开详细分析与探讨,望能够促进生境评价在实际工作的应用质量与水平。  相似文献   
6.
Dispersers are expected to assess breeding habitat quality before settlement. Although cues reflecting habitat quality are well studied, social cues have not been as well evaluated. In this paper, we studied breeding habitat selection during 3 years in a natural population of blue tits, Cyanistes caeruleus, breeding in nest-boxes. Our aim was to investigate if this species used conspecific density and/or reproductive success of con- and heterospecifics (i.e., social cues) in settlement decisions. The patterns observed were consistent with the idea that juveniles, when dispersing from their natal patches, did not react to any of the cues that we tested. In contrast, breeders that dispersed seemed to respond to both conspecific mean patch reproductive success (PRS) and breeding density of the settlement patch in the year of dispersal, their response differing according to their own reproductive success. Indeed, failed breeders moved to areas with high PRS and low density relative to source patches, while successful breeders behaved the opposite. The comparison between juveniles and adults might be modulated by the limited time available to juveniles to gather information on PRS and density at the end of the dispersing year. Adults lacking these time constraints, however, seemed to rely on these conspecific cues although limited by their own quality. Additionally, breeders were more likely to be immigrants in patches with relatively low breeding success and density the previous year, suggesting that settlement is influenced by multiple cues, which may reveal information on different aspects of habitat and be available at different moments. Collectively, our results support the importance of social cues for blue tits’ settlement.  相似文献   
7.
我国高校在防灾减灾类人才培养中存在一些现实困境,如:灾害学的学科地位较低、防灾减灾类学科及专业设置不灵活、学校管理制度及其相关条例的约束等。从我国学位管理制度谈起,通过比较分析国内外高校专业设置与交叉学科发展情况,探讨我国防灾减灾领域学科发展及专业设置对防灾减灾人才培养造成的影响,并提出三点建议:一是加大我国学位管理制度的改革,确保落实高校办学自主权;二是对灾害科学的研究走向系统化、社会化,发展国内高等学校防灾减灾类专业本科教育;三是防灾减灾类专业课程设置从横向和纵向上都要体现综合和交叉的学科属性。  相似文献   
8.
赵雨迪 《环境与发展》2020,(2):203-204,206
我国的环境司法处于发展初期,有关环境纠纷的司法救济程序散落在不同的部门法中。为了维护国家环境安全和公共环境利益,构建环境司法专门化势在必行,但是在特殊的环境保护法院进行专门化的环境审判过程中,出现环境诉讼保护对象的争议性、生态环境损害责任承担的特殊性等问题亟待解决,环境民事公益诉讼和生态环境损害赔偿诉讼等特殊环境诉讼规则应运而生,虽然目前还面临着一些困境,但是整体上构建环境司法体系的进程依然在不断推进。  相似文献   
9.
The development of ecologically sound water allocation strategies that account for the needs of riverine ecosystems is a pressing issue, especially in semiarid river basins. In the Aral Sea Basin, a search for strategies to mitigate ecological and socioeconomic deterioration has been in process since the early 1990s. The Geographic Information System–based simulation tool TUGAI has been developed to support the policy determination process by providing a simple, problem-oriented method to assess ecological effects of alternative water management strategies for the Amudarya River. It combines a multiobjective water allocation model with simple, spatially explicit statistical and rule-based models of landscape dynamics. Changes in environmental conditions are evaluated by a fuzzy habitat suitability index for Populus euphratica, which is the dominant species of the characteristic riverine Tugai forests. Water management scenarios can be developed by altering spatiotemporal water distribution in the delta area or the amount of water inflow into the delta. Outcomes of scenario analysis are qualitative comparisons of the ecological effects of different options for a time period of up to 28 years. The given approach utilizes different types of knowledge, from quantitative hydrological data to qualitative local expert knowledge. The main purpose of the tool is to integrate the knowledge in a comprehensive way to make it available for discussions on alternative policies in moderated workshops with stakeholders. In this article, the modules of the tool, their integration, and three hypothetical scenarios are presented. Based on the experience gained when developing the TUGAI tool, we propose that the general framework can be transferred to other areas where tradeoffs in water allocation between the environment and other water users are of major concern. The potential for a simulation tool to structure and inform a complex resource management situation by involving local experts and stakeholders in the development of possible future scenarios will become increasingly valuable for transparent and participatory resource management.  相似文献   
10.
We evaluated mercury (Hg) in five waterbird species representing three foraging guilds in San Francisco Bay, CA. Fish-eating birds (Forster's and Caspian terns) had the highest Hg concentrations in thier tissues, but concentrations in an invertebrate-foraging shorebird (black-necked stilt) were also elevated. Foraging habitat was important for Hg exposure as illustrated by within-guild differences, where species more associated with marshes and salt ponds had higher concentrations than those more associated with open-bay and tidal mudflats. Importantly, Hg concentrations increased with time spent in the estuary. Surf scoter concentrations tripled over six months, whereas Forster's terns showed an up to 5-fold increase between estuary arrival and breeding. Breeding waterbirds were at elevated risk of Hg-induced reproductive impairment, particularly Forster's terns, in which 48% of breeding birds were at high risk due to their Hg levels. Our results highlight the importance of habitat and exposure timing, in addition to trophic position, on waterbird Hg bioaccumulation and risk.  相似文献   
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