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951.
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
952.
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
953.
954.
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
955.
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
956.
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
957.
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
958.
Joseph N. Lekakis 《Environmental management》1990,14(4):465-473
Environmental protection policies generate an equity question concerning the fair allocation of environmental benefits and
costs. This paper presents evidence from Greece during the 1980s. The findings reveal that Greek environmental policies, in
the form of government self-regulatory programs, are mostly regressive in nature. At the regional level these programs combine
all forms of vertical equity. Since the public sector finances the majority of related expenditures out of taxes, the regressive
elements of environmental policies have been reinforced by discretionary fiscal measures and tax evasion, accompanied by inflation,
which have distorted the country's progressive tax system. 相似文献
959.
Luis Antonio Bojórquez-Tapia Peter F. Ffolliott D. Phillip Guertin 《Environmental management》1990,14(3):317-324
The current Mexican environmental law provides the legal basis for comprehensive land-use planning. Under the law, development
of natural ecosystems must combine goals, policies, and practices towards the sustainable use of natural resources and the
protection of biological diversity. Thus, ecosystem manipulation must be able to counter fragmentation of natural ecosystems
and isolation of natural reserves, while providing for human needs. Assessment of the potential of natural ecosystems and
management impacts are required. Multiple-resource simulation is an assessment and land-use planning tool that permits managers
and decision makers to comply with the law, providing a flexible, user-oriented system that can meet the needs of managers,
conservationists, and researchers. A multiple-resource model and an example of how it can be applied to meet planning needs
is presented for discussion. 相似文献
960.
Charles R. Malone 《Environmental management》1990,14(1):25-32
The US Department of Energy (DOE) plans to conduct site characterization studies at Yucca Mountain, Nevada, to determine if
the location is a suitable site for a nuclear waste repository. In lieu of traditional environmental review in accordance
with the National Environmental Policy Act of 1969, the DOE is relying on an environmental assessment (EA) mandated by the
Nuclear Waste Policy Act of 1982 as the cornerstone of its environmental program for the Yucca Mountain Project. Because of
statutory restrictions, the EA is not based on comprehensive baseline information. Neither does it address fundamentals of
environmental analysis such as ecological integrity and assessment of cumulative impacts. Consequently, the present environmental
program for Yucca Mountain reflects decisions made without complete information and integrated environmental review. The shortcomings
of the program risk compromising the natural integrity of Yucca Mountain and invalidating future assessment of the ability
of a nuclear waste repository located at the site to protect the environment. Significant improvements are needed in the repository
siting program before it can serve as a model of how society can evaluate the long-term environmental consequences of advanced
technologies, as has been suggested. 相似文献