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171.
The number of environmental statutes has increased precipitously over the last twenty years. Regulations to implement these statutes went from four thousand pages in 1978 to over twelve thousand pages in 1992. With the many requirements of the regulatory programs comes a high risk of failure. Applying the continuous improvement principles and tools presented in this article has helped Lockheed meet this challenge by providing a focus and balance in its environmental programs. 相似文献
172.
Steve H. Hanke Robert K. Davis 《Journal of the American Water Resources Association》1974,10(1):54-65
ABSTRACT In this paper, we discuss how user fees and congestion tolls can be used to improve the efficiency and equity with which the inland waterway system is managed. The advantages and disadvantages of various types of user fees (fuel taxes, segment tolls, and license fees) are presented. The rationale for the employment of congestion tolls on congested waterways is discussed. A segment toll that is equated to average variable cost is recommended for uncongested existing waterwyas. When existing waterways are congested, congestion tolls, in addition to the segment tolls, are recommended, A two-part tariff, consisting of segment tolls and an annual license fee, is recommended for “new” uncongested waterways. A three-part tariff, consisting of the first two parts plus congestion tolls, is recommended for “new” congested waterways. 相似文献
173.
McClellan Y August R Gosz J Gann S Parmenter R Nelson M Harper M 《Journal of environmental quality》2003,32(5):1759-1763
The release rates and transformation processes that influence the mobility, biological uptake, and transfer of radionuclides are essential to the assessment of the health effects in the food chain and ecosystem. This study examined concentrations of 222Th in both soil and vegetation at a closed military training site, Kirtland Air Force Base (KAFB), New Mexico. Brazilian sludge was intentionally introduced into the topsoil in the early 1960s to simulate nuclear weapon accidents. Soil (60) and vegetation (120) samples were collected from 1996 to 2000 and analyzed for radionuclides and progeny. High-resolution gamma-ray spectroscopy was used to determine radionuclide activities. The results indicate that the thorium progeny were the predominant contaminant in soil and vegetation. Concentration ratios (CRs) were calculated based on actinium levels. 相似文献
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177.
Application of the DPSIR framework to environmental degradation assessment in northern Ghana 总被引:1,自引:0,他引:1
In many communities in northern Ghana, the environment has been altered by complex natural and human driven forces with significant impact on the lives of their inhabitants. The need to formulate an improved, holistic and consistent methodological approach to assess the problem is critical for sustainable natural resource management. This paper examines the potential of the DPSIR environmental assessment framework utilizing GIS‐based participatory methodology in the assessment of environmental degradation in northern Ghana. Community truthing tools such as key informant interviews, focus group discussions, participant observation and participatory Geographical Information Systems (GIS) were employed as a means of soliciting societal responses integrated to conventional GIS spatial analysis to measure the indicators of the Driving force–Pressure–State–Impacts–Response (DPSIR) assessment framework. Post classification GIS imagery results show a marked natural vegetation decrease of 634 km2 (42%) of the study area with a corresponding increase of 600 km2 (39%) of grasses and built‐up and barren environment in the period of 14 years from 1990 to 2004. This is attributed to extreme climatic conditions and human driven causes such as poverty, population growth, migration and land tenure system. Poverty reduction strategies, amendment of the Mining and Mineral Law (PNDC law 153), improvement of the existing land tenure system and the control of migrants and Fulani herdsmen from neighbouring Burkina Faso were some of the solutions selected by the research participants, to be emphasized in the National Environmental Action Plan (EPA Act 490). This paper concludes that the DPSIR environmental assessment framework is an effective means of organizing complex environmental information to facilitate policy decision making. 相似文献
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179.
Mihok S 《Journal of environmental radioactivity》2004,75(3):233-266
Free-ranging, wild meadow voles (Microtus pennsylvanicus) were exposed to gamma radiation from a (137)Cs irradiator in a series of experiments conducted on six 1-ha meadows within a mixed deciduous forest in Manitoba, Canada. Over a period of 1-1.5 years in each of three experiments, vole populations were monitored with capture-mark-release techniques at nominal exposure rates of 200x, 9000x and 40,000x background. No effects on population or individual characteristics were detected up to the highest exposure rate (81 mGy/d). At this level, third generation voles were monitored up to a lifetime dose of about 5.7 Gy, at a measured dose rate of 44 mGy/d. Smaller numbers of overwintered animals survived and reproduced normally at doses up to 10 Gy. These results are discussed in terms of low-LET, external chronic radiation effects on rodents in the laboratory and the field, relative to current views on appropriate benchmarks for the protection of biota. 相似文献
180.
Temporal Changes in Streamflow and Attribution of Changes to Climate and Landuse in Wisconsin Watersheds 下载免费PDF全文
Rabi Gyawali Steve Greb Paul Block 《Journal of the American Water Resources Association》2015,51(4):1138-1152
Previous historic trends analyses on 21st Century hydrologic data in the United States generally focus on annual flow statistics and have continued to use USGS hydro‐climatic data network (HCDN) stations, although post‐1988 diversions and runoff regulations are not reflected in the HCDN. Using a more recent dataset, Geospatial Attributes of Gages for Evaluating Streamflow, version II (GAGES II), compiled by Falcone (2012), which includes more watersheds with reference conditions, a comprehensive analysis of changes in seasonal, and annual streamflow in Wisconsin watersheds is demonstrated. Given the pronounced influence of seasonal hydrology in Wisconsin watersheds, the objective of this study is to elucidate the nature of temporal (annual, seasonal, and monthly) changes in runoff. Considerable temporal and regional variability was found in annual and seasonal streamflow changes between the two historic periods 1951‐1980 and 1981‐2010 considered in the study. For example, the northern watersheds show relatively small changes in streamflow discharge ranging from ?6.0 to 4.2%, while the southern watersheds show relatively large increases in streamflow discharge ranging from 13.1 to 18.2%. To apportion streamflow changes to climate and nonclimatic factors, a method based on potential evapotranspiration changes is demonstrated. Results show that nonclimatic factors account for more than 60% of changes in annual runoff in Wisconsin watersheds considered in the study. 相似文献