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481.
Amy C. Lewis Joanne Hilton Robert Vocke 《Journal of the American Water Resources Association》2005,41(3):635-643
ABSTRACT: The population in the Jemez y Sangre Water Planning Region of New Mexico has reached the point at which the demand for water exceeds available supplies, particularly when precipitation is below average, as has frequently occurred in recent years. The desire to develop a sustainable water supply that relies on renewable supplies in wet years and preserves the water in storage for times of drought motivated a diverse set of stakeholders in the region to participate in regional water planning. The planning effort culminated in development of the Jemez y Sangre Regional Water Plan, which was adopted by municipal and county governments in the region. The plan assesses and compares water supply and demand in the region and recommends alternatives for protecting and restoring the existing water supply and addressing the pending gap between supply and demand anticipated by the year 2060. To convey to decision makers the alternatives available to solve the future water shortage, option charts were developed to portray the amount of water that could be obtained or conserved through their implementation. The option charts show that the projected gap between supply and demand cannot be met through one alternative only, but will require a combination of alternatives. 相似文献
482.
Gregory W. Characklis 《Journal of the American Water Resources Association》2004,40(3):615-630
ABSTRACT: An analysis is undertaken to determine the conditions under which membrane desalination becomes an economically preferable alternative for treating brackish water supplies. While membrane desalination is more expensive than conventional treatment, it affords benefits beyond those of conventional processes by reducing salinity related damages. An important and largely unexplored issue regards how the added cost of desalination compares to its benefits in terms of damages avoided. A comparative analysis is undertaken over a range of scenarios with the objective of identifying the treatment technology the leads to the lowest “total economic cost,” a term described by the sum of costs related to supply, treatment, and salinity related damages. Using data from a representative region, desalination yields the lowest total economic cost for source waters that exceed “threshold” salinity concentrations below 1,000 mg/l total dissolved solids (TDS). In instances where standard conventional processes require upgrades to maintain compliance with pending regulations (e.g., disinfection byproducts), the cost gap between membrane and conventional processes is reduced and the threshold concentration lowered. Given the inherent uncertainty in both treatment cost and damage estimates, a sensitivity analysis is conducted to determine which factors have the greatest impact on the treatment decision. Results suggest that considering salinity related damages when selecting a treatment technology makes membrane desalination of brackish waters economically attractive under a wider range of circumstances. 相似文献
483.
安阳钢铁集团公司工伤事故统计分析表明,冶炼系统是发生事故较多的系统,各类工伤事故约占事故总数的38%。冶炼系统中,第二炼钢厂是安钢集团公司核心单位,工伤事故特点具有一定代表性。对该厂近10年工伤事故进行了统计分析,总结了事故规律,提出了加强和改进工作的建议和措施,对搞好钢铁冶炼的安全生产具有指导意义。 相似文献
484.
Tony Prato 《Journal of the American Water Resources Association》2003,39(4):935-946
ABSTRACT: The technocratic approach for managing the Missouri River and other large rivers is not effective in resolving conflicts among competing uses of water and dealing with uncertainty about how river ecosystems respond to alternative management actions. Adaptive management offers an alternative way to address these and other issues. It has the potential to alleviate management gridlock and provide lasting solutions to management of the Missouri River and other large river ecosystems. In passive adaptive management, simulation models and expert judgment are combined to select a preferred management action. While passive adaptive management is relatively simple and inexpensive to use, it does not necessarily provide reliable information for making management decisions. Active adaptive management uses statistically designed experiments to test assumptions or hypotheses about ecosystem responses to management actions. It is best carried out by a collaborative working group. Active adaptive management has several advantages, but the inability to satisfy certain prerequisites for successful application makes it more difficult to implement in large river ecosystems. A second‐best approach is proposed here to select, implement, monitor, and evaluate a preferred management action and retain that action provided ecological conditions improve and socioeconomic indicators do not fall below established acceptability limits. 相似文献
485.
Eugene Z. Stakhiv 《Environmental management》1988,12(5):725-748
Cumulative impact analysis is examined from a conceptual decision-making perspective, focusing on its implicit and explicit purposes as suggested within the policy and procedures for environmental impact analysis of the National Environmental Policy Act of 1969 (NEPA) and its implementing regulations. In this article it is also linked to different evaluation and decision-making conventions, contrasting a regulatory context with a comprehensive planning framework. The specific problems that make the application of cumulative impact analysis a virtually intractable evaluation requirement are discussed in connection with the federal regulation of wetlands uses. The relatively familiar US Army Corps of Engineers' (the Corps) permit program, in conjunction with the Environmental Protection Agency's (EPA) responsibilities in managing its share of the Section 404 regulatory program requirements, is used throughout as the realistic context for highlighting certain pragmatic evaluation aspects of cumulative impact assessment.To understand the purposes of cumulative impact analysis (CIA), a key distinction must be made between the implied comprehensive and multiobjective evaluation purposes of CIA, promoted through the principles and policies contained in NEPA, and the more commonly conducted and limited assessment of cumulative effects (ACE), which focuses largely on the ecological effects of human actions. Based on current evaluation practices within the Corps' and EPA's permit programs, it is shown that the commonly used screening approach to regulating wetlands uses is not compatible with the purposes of CIA, nor is the environmental impact statement (EIS) an appropriate vehicle for evaluating the variety of objectives and trade-offs needed as part of CIA. A heuristic model that incorporates the basic elements of CIA is developed, including the idea of trade-offs among social, economic, and environmental protection goals carried out within the context of environmental carrying capacity. 相似文献
486.
Charles A. Whitehurst Elvin J. Dantin Donald Harang 《Journal of the American Water Resources Association》1975,11(4):734-750
ABSTRACT: The Louisiana Environmental Management System (LEMS) is a data processing program developed to aid the Louisiana Joint Legislative Committee on Environmental Quality in decisions leading to resources legislation. Serving as a central data collection and retrieval point for various agencies, the LEMS will maintain assembled information on the location of monitoring stations and coordinate the files of user agencies with data on: land use; air and water quality; meteorological, climatological, and hydrological phenomena; vegetation; fish and wildlife conservation; population; and economics. This data is geographically stored in relation to the state plane coordinate system. For decision making, all pertinent hydrologic, topographic, engineering, cadastral, and other information from separate sources can be automatically mapped as a combined overlay to one of three chosen scales. Land-use patterns are the input data for iterative analyses of present conditions and simulated future human activities for assessing the environmental impact of proposed multiple-purpose water resource developments. 相似文献
487.
K. D. Karatzas 《Water, Air, & Soil Pollution: Focus》2002,2(5-6):669-676
Urban Air Quality Management Systems are software tools that combine air quality models with various software modules like geographical information systems, databases, expert systems and statistical analysis tools. Such systems try to interpret as accurately as possible the complex interactions between various atmospheric, emission, land use and topographic parameters involved in the air pollution management problem, in order to provide support for environmental strategic planning and decision making. As this process involves a huge set of parameters, some of which may only be roughly estimated, air quality management systems tend to aggregate parameters in order to simplify their analysis and make it more effective and operational. Yet, this aggregation may lead to deviations in the analysis results, as proved in this theoretical article, and thus influence the decision making and strategic planning process. According to the findings of this article, such a policy making process should focus primarily on short term measures when dealing with air pollution episode management. 相似文献
488.
Beth Lemberg James W. Mjelde J. Richard Conner Ronald C. Griffin Wesley D. Rosenthal Jerry W. Stuth 《Journal of the American Water Resources Association》2002,38(2):409-422
ABSTRACT: An analytic methodology utilizing models from three disciplines is developed to assess the viability of brush control for water yield in the Frio River basin, Texas. Ecological, hydrologic, and economic models are used to portray changes in forage production and water supply resulting from brush control, and to value supplemental water produced through brush control. Site‐specific biophysical characteristics are used to simulate water yields from brush control across the watershed. Economic benefits from increased animal production for ranchers undertaking brush control are assessed. Benefits to Corpus Christi residential water consumers from ranchers' brush control activities are evaluated using the change in consumer surplus resulting from supplemental water produced through brush control. Results indicate an increase in water yield with brush control on 35 percent of the land area in the basin. However, the cost of brush control is more than the increase in returns it fosters on most range sites. Consumer surplus change for Corpus Christi residents over 25 years is zero under baseline conditions, implying subsidies for brush control in the Frio basin are not worthwhile at this time. 相似文献
489.
Richard Atwater William Blomquist 《Journal of the American Water Resources Association》2002,38(5):1195-1205
ABSTRACT: The Metropolitan Water District of Southern California has for more than 70 years shaped the development of an immense urban region. The district's current strategic planning process therefore could have substantial effects on regional water planning and management. The rate restructuring phase of the planning process has produced a multiple component, cost of service based framework. This paper describes that framework as well as some criticisms that have been directed toward it. The rate restructuring was shaped, and for a while stalled, by old disputes among member agencies over rights to water supplied by Metropolitan. That controversy has diverted attention from the resource management implications of the rate structure. This paper presents an alternative future focused approach to regional integrated water resource planning for Southern California based on projections of current trends and anticipation of future events. This discussion raises the question of how regional integrated water resources planning of this sort may proceed, and what role Metropolitan will play in that process. 相似文献
490.
Leah Greden Mathews Frances R. Homans K. William Easter 《Journal of the American Water Resources Association》2002,38(5):1217-1223
ABSTRACT: In order to make economically efficient decisions about water quality improvements, data on both the costs and benefits of these improvements is needed. However, there has been little research on the benefits of reducing phosphorus pollution which implies that policy decisions are not able to make the comparison of costs and benefits that is essential for economic efficiency. This research attempts to ameliorate this situation by providing an estimate of the benefits of a 40 percent reduction in phosphorus pollution in the Minnesota River. A 1997 mail survey gathered information on Minnesota residents'use of a recreational site on the Minnesota River, the Minnesota Valley National Wildlife Refuge, and their willingness to pay for phosphorus reductions in the Minnesota River. The random effects probit model used in this research to investigate household willingness to pay for phosphorus pollution reductions in the Minnesota River incorporates recent innovations in nonmarket valuation methodology by using both revealed and stated preference data. This model estimated annual household willingness to pay for phosphorus reductions in the Minnesota River at $140. These results may be used in combination with cost estimates to determine the economic efficiency of phosphorus clean up. 相似文献