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101.
William F. Porter Nancy E. Mathews H. Brian Underwood Richard W. Sage Jr. Donald F. Behrend 《Environmental management》1991,15(6):809-814
Populations of white-tailed deer (Odocoileus virginianus) inhabiting many state and national parks and suburban areas have grown to the point that they conflict with human activities.
Conflicts range from destruction of vegetation through browsing to public perception that diseases carried by deer pose threats
to human health. Traditional modes of hunting to control populations are inappropriate in many of these areas because of intense
human development and activity. This article explores an alternative approach for population reduction based on deer social
organization. Female white-tailed deer are highly philopatric and female offspring remain near their dams for life. This suggests
that a population expands slowly as a series of overlapping home ranges in a form analogous to the petals on a rose. Incorporating
the rose petal concept into a model of population growth shows that removal of deer by family unit can potentially alleviate
conflicts in localized areas for as many as 10–15 yr. 相似文献
102.
Joris Mergaert Caroline Anderson Ann Wouters Jean Swings 《Journal of Polymers and the Environment》1994,2(3):177-183
The microbial degradation of tensile test pieces made of poly(3-hydroxybutyrate) [P(3HB)] or copolymers with 10% [P(3HB-co-10%3HV)] and 20% [P(3HB-co-20%3HV)] 3-hydroxyvaleric acid was studied in small household compost heaps. Degradation was measured through loss of weight (surface erosion) and changes in molecular weight and mechanical strength. It was concluded, on the basis of weight loss and loss of mechanical properties, that P(3HB) and P(3HB-co-3HV) plastics were degraded in compost by the action of microorganisms. No decrease inM
w could be detected during the degradation process. The P(3HB-co-20%3HV) copolymer was degraded much faster than the homopolymer and P(3HB-co-10%3HV). One hundred nine microbial strains capable of degrading the polymersin vitro were isolated from the samples used in the biodegradation studies, as well as from two other composts, and identified. They consisted of 61 Gram-negative bacteria (e.g.,Acidovorax facilis), 10 Gram-positive bacteria (mainlyBacillus megaterium), 35Streptomyces strains, and 3 molds. 相似文献
103.
In Hawaii, trace concentrations of pesticides used in the production of pineapple were found in the groundwater supplies of
Mililani Town in the Pearl Harbor Basin on the island of Oahu. Groundwater serves as the major source of drinking water and
residents pay for wellhead treatment of the contaminated water, via their monthly water bill. The agricultural chemical users
within the Pearl Harbor Basin do not include these wellhead treatment costs in their production costs. The agricultural industry
benefits from using pesticides but does not pay the entire societal cost of using these chemicals. In this study we evaluate
the specific financial cost of wellhead treatment, and not the economic value of groundwater. While wellhead treatment costs
could conceivably be shared by several parties, this study focuses on the financial impact of the pineapple industry alone.
This study factors annual wellhead treatment costs into annual pineapple production costs to measure the effect on annual
financial return from pineapple production. Wellhead treatment costs are calculated from the existing granulated activated
carbon (GAC) water treatment facility for Millilani Wells I and II. Pineapple production costs are estimated from previous
cost of production studies. The inclusion of wellhead treatment costs produces different production-cost results, depending
on the scale of analysis. At the local scale, the Mililani wellhead treatment costs can be factored into the production costs
of the pineapple fields, which were probably responsible for contamination of the Mililani Wells, without causing a deficit
in economic return. At the larger regional scale, however, the return from all of the pineapple grown in the Pearl Harbor
Basin can not sustain the cost of wellhead treatmentfor the entire water supply of the basin. Recommendations point to the
prevention of groundwater contamination as more cost-effective measure than wellhead treatment. 相似文献
104.
The United States Soil Conservation Service (SCS) conducts a survey for the purpose of establishing an agricultural land use database. This survey is called the National Resources Inventory (NRI) database. The complex NRI land classification system, in conjunction with the quantitative information gathered by the survey, has numerous applications. The current paper uses the wetland area data gathered by the NRI in 1982 and 1987 to examine empirically the factors that generate wetland loss in the United States. The cross-section regression models listed here use the quantity of wetlands, the stock of drainage capital, the realty value of farmland and drainage costs to explain most of the cross-state variation in wetland loss rates. Wetlands preservation efforts by federal agencies assume that pecuniary economic factors play a decisive role in wetland drainage. The empirical models tested in the present paper validate this assumption. 相似文献
105.
J. Richard Davis 《Environmental management》1985,9(5):443-448
Environmental planning legislation in New South Wales now requires local government authorities to draw up statutory plans that take into account, among other concerns, both the biophysical and the social environmental issues within their jurisdictions. The SIRO-PLAN method of plan production provides a systematic mechanism for fulfilling this requirement. This article describes the application of the method by planning researchers over 18 months to the production of a Local Environmental Plan for a rural local government in New South Wales. The policy formulation, the purposive data collection, and the deliberate adjustment of plans in order to recognize interest group requirements were all found to be valuable features of the method, while the translation of the ultimately chosen land-use plan into the explicit regulatory controls available to the local government authority was found to require further refinement. The capacity of SIRO-PLAN to quantify the resolution of competing environmental concerns in the final plan, although of value to planning researchers, proved too arcane for traditionally trained planners. 相似文献
106.
This study concerns design features of urban parking lots which can increase the perception of such areas as both safe and attractive. College students evaluated the attractiveness and perceived security associated with 180 scenes of parking lots adjacent to commercial and multi-family residential structures in Atlanta and Athens, Georgia, U.S.A. High intergroup correlations (r > 0·90) indicated the reliability of evaluations of both perceived features. Regressions of physical features on perceived security ratings and attractiveness ratings yielded highly predictive models (R2 = 0·76 and 0·80, respectively). For both sets of ratings a Maintenance and Design factor accounted for the most variance. Although attractiveness ratings were higher as the total amount of vegetation increased in a scene, security was in general rated higher only when vegetation was well maintained and appeared to be installed as part of a landscape design. Attractiveness was generally higher for multi-family residential scenes than for commercial scenes. Perceived security was higher for frontal views of structures, especially when entrances were proximate to the viewer. Research implications are discussed in terms of the impact of natural features in urban areas for increasing attractiveness and reducing fear of crime. 相似文献
107.
Martha W. Gilliland Lee Becker Ralph Cady Joe Gabig James Gilley Richard A. Kern Arley Larson Quang M. Nguyen William Powers Raymond Supalla 《Journal of the American Water Resources Association》1985,21(2):281-290
Substantial conflict exists over water management and allocation in the Platte River Basin of Nebraska. An interdisciplinary computer simulation model, representing the water quantity, water quality, environmental, and economic dimensions of the conflict, was developed in order to analyze the tradeoffs among allocation scenarios. Most importantly, decisionmakers and interest groups were involved in model development. Simulation results for a base case and two scenarios are presented. One scenario favors protection of instream flow for wildlife; the other favors water diversions for agriculture. Impacts of the instream flow scenario, as measured by the amount of land irrigated, groundwater levels, the amount of wildlife habitat for cranes and catfish, and net agricultural benefits did not differ greatly from those of the base case. However, impacts of the diversion scenario were substantial. On the negative side, instream flows and wildlife habitat declined an average of 39 percent; while, on the positive side, groundwater levels and net agricultural benefits each increased 6 percent. The modeling process was successful insofar as it promoted an understanding among the highly diverse interest groups of the systems nature of the Basin. One agreement on a water diversion schedule among three of the parties has been reached, partly as a result of this process. More comprehensive compromises have not yet been forged. Our experience, however, indicates that modeling success at the policymaking level depends more on the extent to which the policymakers understand the model than it does on model sophistication. 相似文献
108.
Richard A. Herbert Darrell D. Carlson Gregg J. Wiche 《Journal of the American Water Resources Association》1985,21(6):953-965
The crest-stage gage program in Louisiana was evaluated to determine if the data were adequate for use in developing regional flood-frequency equations and to determine if any crest-stage gage stations could be discontinued. An abundance of data at many crest-stage gage stations and a lack of data for urban areas and flat-slope areas indicated a need for a shift in the number, type, and locations of gages. Correlations and comparisons of annual peak discharges and watershed characteristics of 96 existing stations resulted in the elimination of 72 stations and the addition of one new station, reducing the total network to 25 stations that could be used for future flood-frequency analyses. The adequacy of the reduced network for development and verification of regional flood-frequency equations was tested by comparing a set of regional flood-frequency equations developed using data from the full network with a set developed using data from the reduced network. The results indicate that the crest-stage gage network can be reduced to 25 stations and still provide adequate information for future flood-frequency analyses. 相似文献
109.
Fourteen streams in the Sierra Nevada in the USA were sampled to determine whether diversions of streamflow for hydroelectric development had caused significant changes in riparian vegetation. Several streams showed significant differences in vegetation cover, community composition, or community structure between pairs of diverted and undiverted reaches. On some streams, environmental conditions rather than streamflow diversions may have been responsible for vegetation differences. Streams in the Sierra Nevada respond individualistically to diversions. Prediction of vegetation responses must take into consideration environmental characteristics of specific stream reaches. 相似文献
110.
The author describes his background and relationship to the behavioral geography revolution at Clark. Key events included the independent invention of ‘turf maps’, the Place Perception Project of Blaut, Stea and McCleary, and the synergy of an exceptional cluster of faculty and students. The influence of the revolution on the author's own research has resulted in a radical redirection of effort toward applied research on children's environmental behavior, geographic learning, and participatory design methods in particular. 相似文献