首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   313篇
  免费   19篇
  国内免费   8篇
安全科学   11篇
废物处理   12篇
环保管理   77篇
综合类   29篇
基础理论   82篇
污染及防治   74篇
评价与监测   43篇
社会与环境   11篇
灾害及防治   1篇
  2023年   3篇
  2022年   4篇
  2021年   5篇
  2020年   3篇
  2019年   10篇
  2018年   13篇
  2017年   8篇
  2016年   10篇
  2015年   7篇
  2014年   7篇
  2013年   39篇
  2012年   13篇
  2011年   12篇
  2010年   9篇
  2009年   8篇
  2008年   12篇
  2007年   18篇
  2006年   19篇
  2005年   10篇
  2004年   9篇
  2003年   14篇
  2002年   8篇
  2001年   8篇
  2000年   6篇
  1999年   5篇
  1998年   4篇
  1996年   3篇
  1995年   5篇
  1994年   5篇
  1993年   4篇
  1992年   3篇
  1991年   4篇
  1990年   5篇
  1987年   6篇
  1985年   3篇
  1984年   7篇
  1982年   1篇
  1981年   1篇
  1980年   2篇
  1979年   8篇
  1978年   1篇
  1977年   3篇
  1975年   2篇
  1974年   1篇
  1973年   3篇
  1971年   1篇
  1969年   1篇
  1966年   1篇
  1965年   1篇
  1964年   1篇
排序方式: 共有340条查询结果,搜索用时 31 毫秒
101.
ABSTRACT: Decision parameters affecting combined use of effluent discharges and surface flows and ground water available at Gillespie Dam on the Gila River in Arizona are identified and analyzed. Hydrologic, economic, legal, and institutional parameters are considered separately and in combination. The interrelationships of irrigation subsystems, water use functions, institutional involvement, economic and legal constraints are illustrated. Recent hydrologic studies indicate that the natural flow of the Gila River will increase with the discharge of Phoenix sewage effluent and then there will be a drastic decline when the Palo Verde Nuclear Generating Station commences in 1985. Competition for any increases in effluent discharges and surface flows could be ameliorated through the combined efforts of existing or reorganized entities resulting in sharing of costs and benefits. The analysis leads to recommendations concerning joint use of facilities, proration of fixed and variable costs, and creation of a mutual water company.  相似文献   
102.
The purpose of this paper is to describe how the Level B Water Resources Planning Process was applied to Long Island Sound and the land area around it, to summarize the major findings and recommendations of the study and to comment on the effectiveness of that process and suggest how it might be made more effective in the future.  相似文献   
103.
Researchers have increasingly acknowledged the relative strength of ‘hybrid’ approaches to scenario analysis for exploring the futures of coupled human-nature systems. In this paper, we explain, demonstrate, and provisionally evaluate the usefulness of a simple analytical framework, based on five categories of capital assets, as part of a protocol for overcoming the conversion problem in hybrid scenario analysis. Based on a preliminary application of the framework to a case study in South Africa, we suggest that the five capitals framework has the potential to improve expedience and counter the bias against ‘soft’ drivers in hybrid approaches to scenario analysis. However, in light of the methodological trade-off between rigour and expedience, we suggest that future research needs to compare the available protocols for hybrid scenario analysis by weighing up the relative gain in scenario quality versus the relative cost of scenario construction.  相似文献   
104.
The National Vegetation Classification Standard (NVCS) was implemented at two US National Park Service (NPS) sites in Texas, the Padre Island National Seashore (PINS) and the Lake Meredith National Recreation Area (LMNRA), to provide information for NPS oil and gas management plans. Because NVCS landcover classifications did not exist for these two areas prior to this study, we created landcover classes, through intensive ground and aerial reconnaissance, that characterized the general landscape features and at the same time complied with NVCS guidelines. The created landcover classes were useful for the resource management and were conducive to classification with optical remote sensing systems, such as the Landsat Thematic Mapper (TM). In the LMNRA, topographic elevation data were added to the TM data to reduce confusion between cliff, high plains, and forest classes. Classification accuracies (kappa statistics) of 89.9% (0.89) and 88.2% (0.87) in PINS and LMNRA, respectively, verified that the two NPS landholdings were adequately mapped with TM data. Improved sensor systems with higher spectral and spatial resolutions will ultimately refine the broad classes defined in this classification; however, the landcover classifications created in this study have already provided valuable information for the management of both NPS lands. Habitat information provided by the classifications has aided in the placement of inventory and monitoring plots, has assisted oil and gas operators by providing information on sensitive habitats, and has allowed park managers to better use resources when fighting wildland fires and in protecting visitors and the infrastructure of NPS lands.  相似文献   
105.
Geography inherently fills a 3D space and yet we struggle with displaying geography using, primarily, 2D display devices. Virtual environments offer a more realistically-dimensioned display space and this is being realized in the expanding area of research on 3D Geographic Information Systems (GISs). Traditionally, a GIS has only limited tools for statistical analysis, and 3D GIS research has concentrated on the visualization of the geographical terrain. Here we discuss linking multivariate statistical graphics to geography in the highly immersive C2 virtual reality environment at Iowa State University using mid-Atlantic streams data.  相似文献   
106.
Due to anthropogenic inputs, elevated concentrations of metals frequently occur in aquatic sediments. In order to make defensible estimates of the potential risk of metals in sediments and/or develop sediment quality criteria for metals, it is essential to identify that fraction of the total metal in the sediments that is bioavailable. Studies with a variety of benthic invertebrates indicate that interstitial (pore) water concentrations of metals correspond very well with the bioavailability of metals in test sediments. Many factors may influence pore water concentrations of metals; however, in anaerobic sediments a key phase controlling partitioning of several cationic metals (cadmium, nickel, lead, zinc, copper) into pore water is acid volatile sulfide (AVS). In this paper, we present an overview of the technical basis for predicting bioavailability of cationic metals to benthic organisms based on pore water metal concentrations and metal-AVS relationships. Included are discussions of the advantages and limitations of metal bioavailability predictions based on these parameters, relative both to site-specific assessments and the development of sediment quality criteria.  相似文献   
107.
108.
Book reviews     
The Economics of Art and Culture: An American Perspective

James Heilbrun & Charles M. Gray

New York, Cambridge University Press, 1993, 378 pp., £14.95 pb

Building Cities that Work

Edmund Fowler

Montreal & Kingston, McGill‐Queen's University Press, 1992, 315 pp.

Interactive Decision Making: The Graph Model for Conflict Resolution

Liping Fang, Keith W. Hipel & D. Marc Kilgour

New York, Wiley, 1993, 221 pp., £49.50

The Politics of Nature: Explorations in Green Political Theory

Andrew Dobson & Paul Lucardie (Eds)

London, Routledge, 1993, 240 pp. + xv, £37.50

Urban Transport in Asia: An Operational Agenda for the 1990s, World Bank

Technical Paper No. 224

Peter Midgley

Washington, DC, The World Bank, 1994, 98 pp.

Landscape Ecology: Theory and Application, 2nd edition

Zev Naveh & Arthur Lieberman

New York, Springer‐Verlag, £34.50  相似文献   

109.
Management in the field of environmental protection and risk prevention has evolved to the increasing participation of all stakeholders in the decision-making process. It certainly results from the development of the Information society and the global increase of knowledge of the population, combined with the concerns of the populations related to a sustainable development of our civilisation. Our ‘risk society’, following the big industrial disasters (Flixborough,Tchernobyl, Bhopal, Challenger, and more recently Toulouse), has also developed a cautious attitude towards the role of the expertise when it comes to assessing risks, along with a question of the ability of science to give definite answers.

This has lead in particular to the adoption of the Aarhus convention in 1998 and the evolution of several regulations in the developed countries. For example, in France the new law no. 2003–699 of 30 July 2003 about the ‘prevention of the technological and natural risks and to the compensation for the damages’ has introduced an important innovation into the process of technological risks prevention.

This law has enabled the involvement of the stakeholders in the decision-making process related to risk prevention and has urged the development of specific tools to deal with the complexity of risk management issues, in particular for those related to land-use planning.

As technical support to decision-makers in risk management from both public and private sectors, INERIS has played an important role for the evolution of the French risk management system.

This paper describes an analysis on the difficulty to control major accident hazards in an evolving context where the industrial systems becomes more and more complex and where the expectations of the civil society has increased. Then, the authors describe how an integrated vision for industrial risk management has emerged in France and is being implemented in a new law adopted after the Toulouse disaster.  相似文献   

110.
ABSTRACT: A general framework is proposed for using precipitation estimates from NEXRAD weather radars in raingage network design. NEXRAD precipitation products are used to represent space time rainfall fields, which can be sampled by hypothetical raingage networks. A stochastic model is used to simulate gage observations based on the areal average precipitation for radar grid cells. The stochastic model accounts for subgrid variability of precipitation within the cell and gage measurement errors. The approach is ideally suited to raingage network design in regions with strong climatic variations in rainfall where conventional methods are sometimes lacking. A case study example involving the estimation of areal average precipitation for catchments in the Catskill Mountains illustrates the approach. The case study shows how the simulation approach can be used to quantify the effects of gage density, basin size, spatial variation of precipitation, and gage measurement error, on network estimates of areal average precipitation. Although the quality of NEXRAD precipitation products imposes limitations on their use in network design, weather radars can provide valuable information for empirical assessment of rain‐gage network estimation errors. Still, the biggest challenge in quantifying estimation errors is understanding subgrid spatial variability. The results from the case study show that the spatial correlation of precipitation at subgrid scales (4 km and less) is difficult to quantify, especially for short sampling durations. Network estimation errors for hourly precipitation are extremely sensitive to the uncertainty in subgrid spatial variability, although for storm total accumulation, they are much less sensitive.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号