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991.
992.
993.
James A. Perry David J. Schaeffer Harold W. Kerster Edwin E. Herricks 《Environmental management》1985,9(3):199-207
The planning and execution of water quality management programs requires careful collection and analysis of data coupled with a systematic review and analysis of programmatic success. The environmental audit is a tool which facilitates improved water quality planning and management. This article demonstrates the utility of the environmental audit by reviewing portions of a comprehensive review of the water quality management program for the state of Idaho. The audit is a tool which forces careful design of a sampling program before data are collected. In the audit approach, program objectives are clearly stated prior to initiation of sampling. Stated objectives are also evaluated regularly to identify tension points, that is, conflicts between expectations and reality. In the example taken from Idaho, a management review team followed a directive to redesign the water quality monitoring program. We present a summary of the redesign as proposed by that team, to illustrate the results of a typical review of monitoring programs. That summary is followed by an example of how the proposed program would differ if the audit approach had been used. The two approaches offered both coincident and conflicting recommendations. Management review team and audit recommendations for lake sampling programs were similar even though a different process was used to develop the recommendations. The most striking contrast between the two results lies in the review team's approach to the problem. The directives followed, and the team's responses, concentrate on tools, such as increasing biological monitoring or reliance on monthly BWMP stations. In contrast, the audit results stress addressing management questions for which clear objectives have been stated, depending on specific tools only as needed to meet stated objectives. Although the audit does integrate externalities in its structure, it is little affected by economic or political influences. A major strength of the audit approach is its ability to provide defensible data for management decision making. 相似文献
994.
Estuaries and coastal lagoons are characterized by a strong spatial and temporal variability of physicochemical characteristics and productivity patterns. In these environments, the magnitude and direction of the ecological responses to inorganic nutrient increase (i.e. eutrophication) are difficult to predict. In the framework of the project, New Indicators of Trophic state and environmental quality of marine coastal ecosystems and transitional environments (NITIDA), we analysed benthic indicators of trophic state, ecosystem efficiency, and environmental quality in four different transitional environments. The trophic state of the sediments was assessed in terms of quantity and bioavailability of sediment organic C pools; ecosystem efficiency was determined in terms of the prokaryote efficiency in exploiting enzymatycally degraded organic C; environmental quality was determined in terms of meiofaunal diversity. Here, we provide a synopsis of the results obtained and a meta-analysis of the scores assessments obtained using the different ecological indicators of environmental quality and demonstrate that trophic state, ecosystem efficiency, and biodiversity in transitional ecosystems are closely linked. We conclude that the assessment of the environmental quality of transitional ecosystems should be based upon a battery of trophic state indicators and 'sensors' of ecosystem functioning, efficiency, and quality. 相似文献
995.
The biomarker approach has been used for 25 years to study the environmental quality of marine, brackish and freshwater ecosystems. Biomarkers may indicate health status and can be applied to organisms of all zoological phyla by destructive or non destructive methods. For 5 years we have been using this approach in zooplankton to detect ecotoxicological alterations at low levels of the food chain due to contaminants. Here we review our approach to validate and apply biomarker techniques in zooplankton. We discuss advantages, limitations, some results and future research. We indicate that biomarkers in zooplankton can be used as new indices of trophic status and ecological integrity of Italian marine coastal and lagoon environments, to be included among the tools specified by Italian law D.Lgs. 152/2006. 相似文献
996.
997.
The environmental dimension of national security: A test of systems analysis methods 总被引:2,自引:0,他引:2
Boris N. Porfiriev 《Environmental management》1992,16(6):735-742
The systems approach permits us to analyze national security as a cluster of interconnected elements, in which the environmental
dimension appears to be the most important one. The environmental problem is divided into two main aspects: environmental
security per se and the impact of environment on the overall status of a nation's security. It is argued here that the quality
of life and health serve as both the main objective and the principal criterion of environmental security in a social system.
Indices of these two factors are used in this article as indicators of the state of this type of security. They confirm that
vast areas of Russia, the Ukraine, and Central Asia (especially the Aral Sea region) should be considered as presenting a
substantial risk to local people and even producing global impacts on both natural and man-made systems. Environmental factors
that destabilize national security are also divided into two groups: those that impact social systems directly and negatively
(mainly natural disasters) and technological and sociopolitical agents that cause indirect impacts, in both war and peace
time, as well as in the civil and military sectors of the economy. Developments in the former Soviet Union (the Commonwealth
of Independent States) are used as an illustration of the consequences that such impacts may have on the status of national
security. 相似文献
998.
Priscilla W. Baillie 《Environmental management》1992,16(4):531-540
Development of a marina in a flooded brownstone quarry will require construction of a canal to the Connecticut River through
an isthmus separating the two systems. An environmental audit over a 16-month period developed quantitative limnological data
required by regulatory agencies. The deep quarry basin, protected by high sandstone walls, became strongly stratified in summer.
Development of littoral vegetation in the quarry was prevented by the steep sides of the basin. Unusual characteristics of
the manmade quarry basin, compared to most natural lakes in Connecticut, included a mean depth of 14 m, an intense thermocline,
and negative heterograde oxygen profiles with metalimnetic minima. Alkalinity, conductivity, and nutrient levels differed
significantly between the quarry and the river. Mean chlorophyll a concentrations in the two systems were similar, but the
distribution of phytoplankton classes were quite different. The environmental audit, by comparing physical, chemical, and
biological characteristics of the quarry to those of the river, allowed prediction of changes in trophic status when the two
systems are joined. 相似文献
999.
William O. Rasmussen 《Environmental management》1992,16(3):389-396
Several approaches can be used to define and construct visual buffer strips around proposed new facility sites in a forested
environment. A visual buffer strip of a given value, defines a region around an object within which the probability of an
unblocked view of all or portions of it by an observer are less than the buffer strip probability value. Two primary approaches
are used to define visual buffer strips that take into account the size of the vegetative elements and their individual effects
on visibility. Several variations and combinations of the approaches are possible. One approach defines a visual buffer strip
based on the average probability of a clear view of points along the object by an observer; the other approach is based on
the visibility of the feature as a whole. The computation and construction of visual buffer strips based on these two concepts
are presented. Comparisons of the two approaches for specific feature shapes are also described. 相似文献
1000.
Peter Martin 《Environmental management》1991,15(6):773-783
Substantial land degradation of agricultural catchments in Australia has resulted from the importation of European farming
methods and the large-scale clearing of land. Rural communities are now being encouraged by government to take responsibility
for environmental care.
The importance of community involvement is supported by the view that environmental problems are a function of interactions
between people and their environment. It is suggested that the commonly held view that community groups cannot care for their
resources is due to inappropriate social institutions rather that any inherent disability in people.
The communicative catchment is developed as a vision for environmental care into the future. This concept emerges from a critique
of resource management through the catchment metaphors of the reduced, mechanical, and the complex, evolving catchment, which
reflect the development of systemic and people-centered approaches to environmental care. The communicative catchment is one
where both community and resource managers participate collaboratively in environmental care. A methodology based on action
research and systemic thinking (systemic action research) is proposed as a way of moving towards the communicative catchment
of the future. Action research is a way of taking action in organizations and communities that is participative and informed
by theory, while systemic thinking takes into account the interconnections and relationships between social and natural worlds.
The proposed vision, methodology, and practical operating principles stem from involvement in an action research project looking
at extension strategies for the implementation of total catchment management in the Hunter Valley, New South Wales. 相似文献