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991.
Nature quality in relation to farming is a complex field. It involves different traditions and interests, different views of what nature is, and different ways of valuing nature. Furthermore there is a general lack of empirical data on many aspects of nature quality in the farmed landscape. In this paper we discuss nature quality from the perspective of organic farming, which has its own values and goals in relation to nature – the Ecologist View of Nature. This is in contrast to the Culturist View characteristic of much conventional agriculture and the Naturalist View characteristic of the traditional biological approach to nature quality. This threefold distinction forms a framework for exploration of nature quality criteria in the farmed landscape. The traditional work on nature quality has mainly focused on biological interests based on a Naturalist View of Nature. In this paper we will explore how criteria for nature quality based on the Ecologist View can be developed and thereby feed into the ongoing discussion of the development of the organic farming practices. We suggest additional criteria for nature quality based on an Ecologist View of Nature: biodiversity, habitat diversity, extent and structure, functional integrity of habitats and agro-ecosystems, landscape integrity, accessibility, and experientiality. The larger set of Naturalist and Ecologist criteria can provide a wider and more balanced basis for developing nature quality indicators that are relevant in the farmed landscapes. This broader approach to nature quality is also expected to benefit the general societal discussions and decisions on farming and nature.  相似文献   
992.
In 1892, the British agricultural authorities introduced a policy of slaughtering animals infected with foot and mouth disease (FMD). This measure endured throughout the 20th century and formed a base line upon which officials superimposed the controversial "contiguous cull" policy during the devastating 2001 epidemic. Proponents of the slaughter frequently emphasized its capacity to eliminate FMD from Britain, and claimed that it was both cheaper and more effective than the alternative policies of isolation and vaccination. However, their discussions reveal that a less obvious but nonetheless important reason for maintaining the slaughter policy was the conviction that in its manner of operation and its outcomes, it benefited the state and status of the British nation. To its supporters, slaughter was far more than a method of disease control; it acted also as a moralizing and civilizing force, an indicator of veterinary ability and a "virility symbol" of British international leadership. This "cultural" rationale for FMD control by slaughter declined during the late 20th century and was wholly undermined by the 2001 epidemic, when extensive culling failed to convey the intended image of an organized, enlightened Britain.  相似文献   
993.
基于“3S”技术构建农业灾害监测信息系统   总被引:25,自引:1,他引:24  
张金恒  朱德柱 《灾害学》2002,17(2):76-81
本文从介绍遥感、地理信息系统、全球定位系统在建设农业灾害监测信息系统中的特点和优势出发,阐述了“3S”技术在农业灾害监测信息系统中的作用。在此基础上,提出了基于“3S”技术建设农业灾害监测信息系统的构想。  相似文献   
994.
Recent Italian laws mandate the consideration of environmental factors in local plans, especially at the provincial level of government. The plan for the province of Cremona in northern Italy illustrates the integration of the environment in provincial-level planning. The Cremona plan was developed through an ecological planning approach that occurred from 1994 to 1998. As part of this process, the planning team designed an environmental sustainability index. This index was integrated with an environmental capability analysis. To improve the quality of the Cremona landscape, the planning team developed an ecological network. This network seeks to weave together the natural areas of the province, especially by connecting provincial parks to regional river parks throughout Lombardy. The experience of the Cremona provincial plan has implications for environmental management elsewhere in Italy, Europe, and abroad.  相似文献   
995.
The degradation of water quality in many groundwaters of Europe is a major source of concern. Rises in turbidity and nitrate concentrations represent present or potential threats for the quality of drinking water in rural areas. They are for the most part a consequence of agricultural intensification which has considerably affected land cover and land use in recent decades. In our case-study (a karstic catchment) the mechanisms which explain changes in water quality, as far as turbidity and nitrate are concerned, result from a strong continuity between surface and underground waters. The karstic system of the Brionne Basin can be considered as both the focus of rapid horizontal flows (runoff, a rapid process in which rainwater reaches the spring directly through sinkholes) and slow vertical flows (leaching, in which rainwater filters through the soil to the spring). A hierarchical approach to the water pollution problem of the basin suggests that turbidity or nitrate concentrations peak during heavy rain episodes and are short-term events. In terms of management, this implies that the solution to water pollution caused by such events is also short-term and can therefore be addressed at a local scale. The rise of nitrate concentrations during the past twenty years is the main concern. The solution can only be found at a global scale (all the catchment area must be taken in account: land plots and their spatial configuration), and by taking a long-term approach.  相似文献   
996.
Environmental Impact Evaluation Model for Industrial Processes   总被引:4,自引:0,他引:4  
This paper proposes a model to evaluate the environmental impact of manufacturing processes. This model uses the potency factor approach to classify environmental impacts into five ecological health impact groups and uses their toxicological, cancer, and physical effects as the bases to rate the seven groups of human health impacts. The environmental impacts in each impact group are reported, and their hazard scores on ecological and human health are determined. The model also generates a single score for the overall environmental impacts of a process. This single score system helps to identify, among all the viable processes, which is the most environmentally friendly process. This model can serve as a tool to highlight the potential environmental hazards of process operations and to provide information about environmental performance for decision making. The model has been developed into a computer software program, Environmental Impact Evaluation System, and is demonstrated by using the processes employed for the manufacture of paper bags.  相似文献   
997.
The Groundwater Protection Project at the US Department of Energy Hanford Site in Washington State is currently developing the means to assess the cumulative impact to human and ecological health and the regional economy and cultures from radioactive and chemical waste that will remain at the Hanford Site after the site closes. This integrated system is known as the System Assessment Capability (SAC). The SAC Risk/Impact Module discussed in the article uses media- and time-specific concentrations of contaminants estimated by the transport models of the integrated system to project potential impacts on the ecology of the Columbia River corridor, the health of persons who might live in or use the corridor or the upland Hanford environment, the local economy, and cultural resources. Preliminary Monte Carlo realizations from the SAC modeling system demonstrate the feasibility of large-scale uncertainty analysis of the complex relationships in the environmental transport of contaminants on the one hand and ecological, human, cultural, and economic risk on the other. Initial impact results show very small long-term risks for the 10 radionuclides and chemicals evaluated. The analysis also helps determine science priorities to reduce uncertainty and suggests what actions matter to reduce risks.  相似文献   
998.
农业循环经济的理论与实践   总被引:12,自引:1,他引:12  
发展农业循环经济是解决我国"三农"问题的有效途径.本文首先从农业可持续发展观的形成、农业循环经济的理论基础、农业循环经济的主要内容三方面对农业循环经济的基本理论进行论述.然后,对秦皇岛市农业生产存在的问题进行了分析.最后,提出了秦皇岛市发展农业循环经济的对策.  相似文献   
999.
ABSTRACT: Forest and grass riparian buffers have been shown to be effective best management practices for controlling nonpoint source pollution. However, little research has been conducted on giant cane [Arundinaria gigantea (Walt. Muhl.)], a formerly common bamboo species, native to the lower midwestern and southeastern United States, and its ability to reduce nutrient loads to streams. From May 2002 through May 2003, orthophosphate or dissolved reactive phosphate (DRP) concentrations in ground water were measured at successive distances from the field edge through 12 m of riparian buffers of both giant cane and mixed hardwood forest along three streams draining agricultural land in the Cache River watershed in southern Illinois. Giant cane and mixed hardwood forest did not differ in their DRP sequestration abilities. Ground water DRP concentrations were significantly reduced (14 percent) in the first 1.5 m of the buffers, and there was an overall 28 percent reduction in DRP concentration by 12 m from the field edge. The relatively low DRP reductions compared to other studies could be attributed to high DRP input levels, narrow (12 m) buffer lengths, and/or mature (28 to 48 year old) riparian vegetation.  相似文献   
1000.
ABSTRACT: Grouping of nitrate‐nitrogen (NO3‐N) leaching losses from agricultural fields into spatial clusters can help determine the cause/effect relationships for their occurrence. This study was designed to investigate the spatial relationships of low, medium, and high NO3‐N leaching losses clusters with soil and landscape attributes using cluster and discriminant analysis and the map overlay capability of a geographical information system (GIS). Field measured data of a six‐year (1993 through 1998) study on NO3‐N leaching losses from 36 experimental fields at the Iowa State University's northeastern research center near Nashua, Iowa, were normalized on an annual basis to compare over the years. The cluster analysis resulted in the formation of three clusters based on the satisfactory evaluation criteria of pseudo‐F statistic, cubic clustering criterion, and R2 values. The discriminant analysis, carried out on the basis of clusters, identified elevation and subsurface drainage as the factors that contributed significantly (p > 0.01) in discriminating among these clusters. The verification of discriminant functions developed on these factors predicted the cluster membership for all the groups with an overall accuracy of 86 percent. The map overlay analyses of GIS showed that spatial occurrence of the clusters transporting high NO3‐N leaching losses was affected by the interaction of soil type and elevation levels.  相似文献   
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