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891.
Duyzer Jan Nijenhuis Bas Weststrate Hilbrand 《Water, Air, & Soil Pollution: Focus》2001,1(5-6):131-144
Passive samplers were used from 1996 to 1999 in a dense network to monitorthe concentrations of ammonia in air, in four agricultural areas in The Netherlands. To show representative patterns, sampling was not made within 50 m of livestock buildings and stores. The concentration of ammonia varies typically between 10 and 40 g m-3 within a few kilometres in these areas. The interpretation of the measurements was supported by calculations with OPS, a Lagrangian dispersion model. Model calculations were based on a high-resolution database that included estimates of the ammonia emission of each farm in the area and emissions from surface application of manure at a 250 × 250 m scale. The model underestimated the observed ammonia concentrations by nearly a factor of two over most of the area. This result was attributed to underestimation of the ammonia emission in the models. And the ammonia emissions from field application of manure seem to be seriously underestimated. A detailed analysis of model results and measurements showed that the observed decrease of the ammonia concentration in the study period was partly due to changes in meteorological conditions during the study period and partly due to the reduced amount of manure applied in 1998. 相似文献
892.
Philip N. Owens William H. Blake Ellen L. Petticrew 《Water, Air, & Soil Pollution: Focus》2006,6(5-6):637-645
This paper describes a study examining the potential of mineral magnetic, geochemical and organic properties to determine
if a 2003 wildfire in a catchment in British Columbia, Canada, caused a change in the sources of the suspended sediment transported
in the channel relative to a nearby unburnt (reference) catchment. The results show that some of the properties offer the
potential to determine sediment sources in the unburnt catchment. However, the 2003 wildfire modified the concentrations of
some properties and this can either compromise or enhance their ability as tracers in the burnt catchment. At present, the
source tracing results are inconclusive. This has implications for the use of certain properties as fingerprints and raises
important issues about approaches to sediment source identification. 相似文献
893.
50年来秦皇岛市气候明显变暖,多年平均气温上升约2℃;同时变干,降水减少18.3%,进而使河流径流也明显减少,其幅度超过30%。河流径流减少给生态系统带来广泛复杂的影响,也给农业、工业、城乡建设带来威胁,因此必须尽快采取发展节水技术、污水治理循环利用、海水淡化等措施。 相似文献
894.
物系管理与可持续发展 总被引:6,自引:0,他引:6
该文回顾德国自60年代以来,从“末端治理型”环保政策到现在提出“物系管理”的发展变化,介绍了德国环境保护工作的成功与不足。从物系管理的产生背景出发,探讨了物系管理的概念、意义、应用实践、面临的困难。此外,该文还阐明物系管理可以成为促进中国可持续发展的一个及时、有效的工具。 相似文献
895.
The near shore coastal and marine environment of several Caribbean islands is their most biologically productive and economically important zone. However, almost all landbased activities possess the real potential of degrading the quality of near shore waters and ultimately diminishing the utility of the marine resource. This condition is largely attributed to the individual smallness of the islands and their geographic proximity to each other.
Available sanitary water quality data from across the region indicated that while recreational areas are in general safe for water contact activities, bacterial densities in excess of several international criteria are consistently recorded in harbours. Organochlorine pesticide residues were generally in the 5 ng l-1 range in unfiltered sea water but were significantly higher (1-100) ng g-1 in limited samples of sediment and biota. Additional data requirements to gain further insight into the current state of the Caribbean environment are also identified.
A summary of the major land based sources of marine pollution (including sewage, industrial effluents and agricultural run-off) in the insular Caribbean is presented. 相似文献
Available sanitary water quality data from across the region indicated that while recreational areas are in general safe for water contact activities, bacterial densities in excess of several international criteria are consistently recorded in harbours. Organochlorine pesticide residues were generally in the 5 ng l-1 range in unfiltered sea water but were significantly higher (1-100) ng g-1 in limited samples of sediment and biota. Additional data requirements to gain further insight into the current state of the Caribbean environment are also identified.
A summary of the major land based sources of marine pollution (including sewage, industrial effluents and agricultural run-off) in the insular Caribbean is presented. 相似文献
896.
Peter Gripaios 《Journal of Environmental Planning and Management》1984,27(1):43-44
The recent central government paper on regional industrial development heralds a reduced role for regional policy, in contrast with the Regional Studies Association inquiry into regional problems in the U.K. A brief exploration of the central government views leads to the paper concluding with a call for an increase in regional planning and for regional planning authorities. 相似文献
897.
Tzay-Rong Jenq Marvin L. Granstrom Shing-Fu Hsueh Christopher G. Uchrin 《Journal of the American Water Resources Association》1984,20(4):511-520
ABSTRACT A linear programming model to assess the cost-effectiveness of appropriate point and nonpoint phosphorus control measures was constructed for Carnegie Lake, an eutrophic lake located in Mercer County, New Jersey. The resultant model was tested for present and future conditions. Feasible solutions were obtained only after significant relaxation of receiving water quality standards. The high levels of point source treatment required to meet the in-stream water quality standards and the mesotrophic loading conditions suggest that a source control solution may not be feasible. 相似文献
898.
J. B. Goddard 《Journal of Environmental Planning and Management》1987,30(1):41-49
This paper attempts five tasks. First, it briefly traces the collapse of regional economic planning since the mid 1970s. Second, it re‐assesses the case for regional economic planning. Third it asks whether a statutory economic development role for local authorities is the way forward. Fourthly, it critically evaluates current practice in economic development in a depressed area using the Newcastle City region as an example. Finally the paper concludes by outlining the nature of the applied research necessary to underpin a more rational approach to regional economic development planning, referring to the example of the Regional Industrial Research Unit established in the University of Newcastle upon Tyne. 相似文献
899.
Robert H. Fraser Maureen V. Warren Paul K Barten 《Journal of the American Water Resources Association》1995,31(6):991-1000
ABSTRACT: A fundamental problem in protecting surface drinking water supplies is the identification of sites highly susceptible to soil erosion and other forms of nonpoint source (NPS) pollution. The New York City Department of Environmental Protection is trying to identify erodible sites as part of a program aimed at avoiding costly filtration. New York City's 2,000 square mile watershed system is well suited for analysis with geographic information systems (GIS); an increasingly important tool to determine the spatial distribution of sensitive NPS pollution areas. This study used a GIS to compare three land cover sources for input into the Modified Universal Soil Loss Equation (MUSLE), a model estimating soil loss from rangeland and forests, for a tributary watershed within New York City's water supply system. Sources included both conventional data (aerial photography) and Landsat data (MSS and TM images). Although land cover classifications varied significantly across these sources, location-specific and aggregate watershed predictions of the MUSLE were very similar. We conclude that using Landsat TM imagery with a hybrid classification algorithm provides a rapid, objective means of developing large area land cover databases for use in the MUSLE, thus presenting an attractive alternative to photo interpretation. 相似文献
900.
Austin Reilly 《Journal of Environmental Planning and Management》1986,29(2):89-91
A currently fashionable method of industrial diversification is ‘technology transfer’. The paper discusses the new mood of positive thinking within Scottish industry, and the role of the Scottish Development Agency's Technology Transfer Division in responding to the approaches received for specialist support. The author concludes that technology can have a major impact on many of the variables which contribute to the performance of a regional economy. 相似文献