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631.
Riparian buffer zone management is an area of increasing relevance as human modification of the landscape continues unabated. Land and water resource managers are continually challenged to maintain stream ecosystem integrity and water quality in the context of rapidly changing land use, which often offsets management gains. Approaches are needed not only to map vegetation cover in riparian zones, but also to monitor the changes taking place, target restoration activities, and assess the success of previous management actions. To date, these objectives have been difficult to meet using traditional techniques based on aerial photos and field visits, particularly over large areas. Recent advances in remote sensing have the potential to substantially aid buffer zone management. Very high resolution imagery is now available that allows detailed mapping and monitoring of buffer zone vegetation and provides a basis for consistent assessments using moderately high resolution remote sensing (e.g., Landsat). Laser‐based remote sensing is another advance that permits even more detailed information on buffer zone properties, such as refined topographic derivatives and multidimensional vegetation structure. These sources of image data and map information are reviewed in this paper, examples of their application to riparian buffer mapping and stream health assessment are provided, and future prospects for improved buffer monitoring are discussed.  相似文献   
632.
ABSTRACT. As a result of several investigations conducted in the Department of Civil Engineering through the Water Resources Research Center at The University of Tennessee, dating from 1966 to the present, a rather comprehensive surveillance of water quality conditions has been maintained in Forth Loudoun Reservoir on the Tennessee River near Knowville, Tennessee. During the period covered by these investigations, the Knoxville Third Creek Sewage Treatment Plant was upgraded from a primary plant to a secondary (activated sludge) treatment plant. Comparison of the collected data is being undertaken herein to elucidate the impact of these modifications upon water quality conditions in the reservoir. Consideration is given to the improvements of water quality as related to the expenditure for modification of the treatment facilities. In addition, comment is directed toward the public health significance of the water quality conditions determined.  相似文献   
633.
通过学习贯彻《职业安全健康管理体系的指导意见》和《职业安全健康管理体系审核规范》,阐述了学习体会和实际应用中的建议。  相似文献   
634.
As freshwater becomes increasingly scarce due to population growth, urbanisation and, probably, climate change, the use of wastewater in agriculture, aquaculture, groundwater recharge and in other areas will increase. In some cases, wastewater is the only water resource available to poor, subsistence-level farming communities. Although there are benefits to using wastewater in agriculture—such as better nutrition and food security for many households—uncontrolled use of wastewater is frequently associated with significant negative human health impacts. These health impacts can be minimized when good management practices are implemented. In this paper the existing situation, in relation to water resources availability, wastewater treatment and reuse in Morocco and Palestine, is presented.  相似文献   
635.
Spatial proximity of emissions sources to receptors may affect sensitivity to potential adverse human health effects. This research investigates whether receptor sensitivity to the location of emission sources can be utilized efficiently to minimize health risk in selecting sites for industrial enterprises, thermal electric stations, etc. A sensitivity function that is independent of the location of pre-existing emission sources is derived and applied to Minsk, Belarus. The function estimates exposures based on weather and climatic conditions as well as the distribution of population density at a given locality. Arraying prospective sites based on their sensitivity function magnitude provides a technique for minimizing health risk based on receptor sensitivity to the spatial proximity of atmospheric emissions sources.  相似文献   
636.
Environmental decision-making and policy-making at all levels refers necessarily to synthetic, approximate quantification of environmental properties such as vulnerability, conservation status, and ability to recover after perturbation. Knowledge of such properties is essential to informed decision-making, but their definition is controversial and their precise characterization requires investments in research, modeling, and data collection that are only possible in the most developed countries. Environmental agencies and governments worldwide have increasingly requested numerical quantification or semiquantitative ranking of such attributes at the ecosystem, landscape, and country level. We do not have a theory to guide their calculation, in general or specific contexts, particularly with the amount of resources usually available in such cases. As a result, these measures are often calculated with little scientific justification and high subjectivity, and such doubtful approximations are used for critical decision-making. This problem applies particularly to countries with weak economies, such as small island states, where the most precious environmental resources are often concentrated. This paper discusses frameworks for a “least disappointing,” approximate quantification of environmental vulnerability. After a review of recent research and recent attempts to quantify environmental vulnerability, we discuss models and theoretical frameworks for obtaining an approximate, standardizable vulnerability indicator of minimal subjectivity and maximum generality. We also discuss issues of empirical testing and comparability between indicators developed for different environments. To assess the state of the art, we describe an independent ongoing project developed in the South Pacific area and aimed to the comparative evaluation of the vulnerability of arbitrary countries.  相似文献   
637.
Assessing Landscape Health: A Case Study from Northeastern Italy   总被引:17,自引:0,他引:17  
This article investigates the concept of biophysical landscape health for what are termed “highly governed landscapes.” It proposes a definition of landscape health along with a preliminary diagnostic model and methods. The idea of landscape health derives from the emerging integrative science of ecosystem health, which seeks to diagnose ecosystem condition as humans diagnose human health. Highly governed landscapes, such as the reclaimed areas of coastal northeastern Italy, are landscapes that have been subject to even greater degrees of human manipulation than normal cultural landscapes. These highly altered landscapes are not easily served by existing environmental paradigms and concepts of health are seen to have numerous advantages. This paper condenses a broader investigation of landscape health into three main sections. A brief review of the literature is followed by a case study, which details two different phases of landscape transformation in the Lower Piave area of northeastern Italy. A definition and general parameters of biophysical landscape health are then presented after this background stage. Some key parameters of biophysical health include absence of distress and risk factors, sustainability, biodiversity, resilience, and balance. For certain parameters, a preliminary landscape health diagnostic framework is presented that includes potential diagnostic methods and thresholds based on findings from this case study. At the paper's conclusion, a summary diagnostic model is presented, which suggests a process needed to implement landscape health assessment into practice.  相似文献   
638.
推行OHSMS过程中管理责任制的探讨   总被引:1,自引:1,他引:0  
结合石油、天然气行业建立 HSE(健康、安全、环境 )管理体系的实践 ,归纳了在企业推行职业安全卫生管理体系 (OHSMS)过程中运用管理责任制的基本内容 ;根据领导科学和安全科学理论 ,采取与实际分析相结合的方法 ,论述了推行 OHSMS过程中安全管理责任制的必要性、科学性和适用性。  相似文献   
639.
杜仲保健醋饮料的研制   总被引:2,自引:0,他引:2  
介绍了杜仲保健醋饮料的生产工艺,并通过正交试验,探讨了合理的配方和加工技术。  相似文献   
640.
The paper argues health risk management in Developing Countries cannot be sustainable unless it is conceived, planned, implemented and maintained by community-led multi-stakeholder groups using an integrated capacity building process with five components: (1) education and awareness raising; (2) strengthening information resources and decision making; (3) strengthening regulations and compliance; (4) improving basic sanitation infrastructure; and (5) stimulating the market for support products and services for health and environment sectors. Occupational and environmental health professionals with cross-disciplinary understanding are uniquely qualified to build much-needed bridges between stakeholders, risk science and policy. They should adopt a cost-effective mentality, adapting models/methods used in developed countries to developing country contexts, negotiating political obstacles and understanding cultural differences in risk sources, exposures and perceptions. Stakeholders – health professionals, community representatives, officials, NGOs/advocacy groups, industries, and providers of products/services – collaborate to detect needs, mobilize resources, design, develop, implement, consolidate and maintain interventions to priority problems. Field experience in Mexico supports the argument. This sustainability process is adaptable to other keystone development sectors like soil and water resources stewardship, biodiversity conservation, agriculture and energy.  相似文献   
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