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421.
Development projects in tropical forests can impact biodiversity.Assessment and monitoring programs based on the principles of adaptive management assist managers to identify and reduce suchimpacts. The small mammal community is one important component ofa forest ecosystem that may be impacted by development projects. In 1996, a natural gas exploration project was initiated in a Peruvian rainforest. The Smithsonian Institution's Monitoring andAssessment of Biodiversity program cooperated with Shell Prospecting and Development Peru to establish an adaptive management program to protect the region's biodiversity. In thisarticle, we discuss the role of assessing and monitoring small mammals in relation to the natural gas project. We outline theconceptual issues involved in establishing an assessment andmonitoring program, including setting objectives, evaluating the results and making appropriate decisions. We also summarizethe steps taken to implement the small mammal assessment, provideresults from the assessment and discuss protocols to identifyappropriate species for monitoring.  相似文献   
422.
Many development projects intended to exploit natural resourcesare occurring in fragile ecosystems, and therefore the need forsound biodiversity assessment and monitoring programs is growing.Large mammals are important components of these fragile ecosystems, yet there are few strategies that attempt to assess and monitor entire large mammal communities in relation to development projects. We propose the use of two indices applied within a framework of adaptive management. An occurrence indexassesses the composition and distribution of large mammals at a site, and an abundance index monitors the abundance of large mammals over time in relation to development. We discuss the design, applicability and effectiveness of these indices based onour experience with a natural gas development project in the Amazon forests of southeastern Peru.  相似文献   
423.
We developed an assessment and monitoring plan for birds in connection with the exploration and potential development of a large natural gas field in the Lower Urubamba drainage of Peru, a project of Shell Prospecting and Development Peru (SPDP). Our objectives were to: (1) inventory the birds in the area, including information on habitat use and abundance, and (2) devise long-term monitoring protocols for birds. We sampled birds through a combination of visual and auditory surveys and mist-netting at 4 well sites and 3 sites along the Urubamba and Camisea rivers. We recorded 420 speciesduring 135 days of field work. We consider the highest prioritiesfor a future monitoring program to be: (1) establish whether edge effects are occurring at well sites, along roads and alongthe planned pipeline route and determine the significance and extent of these effects and (2) assess the impact of increased human access to the area on game and other exploited species. The remoteness of the area, its rugged terrain and dense vegetation and the lack of trained personnel limit the choice of survey and monitoring methods. We recommend use of mist-netting and transects for monitoring edge effects and useof transects for monitoring game and other exploited species.  相似文献   
424.
A model for simulation of solute transport in a dynamic stream–aquifer system is developed by integrating four existing sub-models. Interface packages are created to link the sub-models. The developed model is successfully used to simulate chloride transport in the stream–aquifer system of the Arkansas River and the Equus Beds Aquifer in Kansas and demonstrates that chloride concentration in the aquifer decreases in the vicinity of the simulated channel over time.  相似文献   
425.
A mathematical model that expresses Total trihalomethane (TTHM) concentration in terms of initial chlorine concentration, total organic carbon, bromide ion concentration, contact time, and pH is developed for Zai water treatment plant which supplies water to Jabal Amman. The developed mathematical model is for constant temperature of 20°C. To adjust model calculated TTHM concentrations for temperatures other than 20°C, another mathematical model that expresses TTHM growth rate as function of temperature is also developed. To test the ability of the two developed models in predicting TTHM concentrations throughout water supplies, a sampling program that aimed at measuring TTHM concentrations in addition to the predictors in the two developed mathematical models namely; chlorine concentration, bromide ion concentration, total organic carbon, temperature and pH throughout Jabal Amman water supply was conducted. The two developed mathematical models and WaterCad, which was used to determine water age, were used to predict TTHM concentrations throughout Jabal Amman water supply. Predicted TTHM concentrations were compared to actual TTHM concentrations measured during the sampling program. Results showed that there is good agreement between measured and, calculated TTHM concentrations, which means that the method presented in this paper, can be used to obtain good estimates of TTHM concentrations throughout networks.  相似文献   
426.
ABSTRACT: This paper reviews the processes that occurred during an application of the Metropolitan Water District (MWD)-MAIN water use forecasting system for the City of Salinas, California. The review includes an analysis of sources of available data, methods for estimating input data, calibration, and verification of the MWD-MAIN System, and an evaluation of the reliability of system output. We found that inexperienced users can have difficulty understanding the level of skill, knowledge, and amount of data that are required to produce reliable forecasts. Some of the issues associated with application of the MWD-MAIN System include the following:
  • ? All input data needed for accurate forecasts simply are not available for many cities and towns.
  • ? The data requirements are more extensive than many users anticipate.
  • ? Substantial requirements for manipulation of input data produces opportunity for error that creates major time demands in troubleshooting.
  • ? Calibration and verification for specific uses can be substantially more difficult than is readily apparent from the guidance manual.
  • ? Independent validity checks need to be done to validate system output.
  • ? If specified calibrating procedures do not produce reasonable results, reestimating slope coefficients is an option, but this requires resources and expertise that can easily exceed the limits of most users.
These are problems typical of most complex models. Reviews such as this can help users to appreciate the level of data required, and to use the MWD-MAIN System in a more effective and efficient manner.  相似文献   
427.
ABSTRACT: Although the curve number method of the Natural Resources Conservation Service has been used as the foundation of the hydrology algorithms in many nonpoint source water quality models, there are significant problematic issues with the way it has been implemented and interpreted that are not generally recognized. This usage is based on misconceptions about the meaning of the runoff value that the method computes, which is a likely fundamental cause of uncertainty in subsequent erosion and pollutant loading predictions dependent on this value. As a result, there are some major limitations on the conclusions and decisions about the effects of management practices on water quality that can be supported with current nonpoint source water quality models. They also cannot supply the detailed quantitative and spatial information needed to address emerging issues. A key prerequisite for improving model predictions is to improve the hydrologic algorithms contained within them. The use of the curve number method is still appropriate for flood hydrograph engineering applications, but more physically based algorithms that simulate all streamflow generating processes are needed for nonpoint source water quality modeling. Spatially distributed hydrologic modeling has tremendous potential in achieving this goal.  相似文献   
428.
A study of the piedmont of the Newberry Mountains near Laughlin, Nevada, demonstrates that geologic information can improve the scientific basis of flood‐hazard management on alluvial fans in desert areas. Comparison of geologic information against flood insurance rate maps (FIRMs) reveals flaws in conventional methods for flood hazard delineation in this setting. Geologic evidence indicates that large parts of the Newberry piedmont have been isolated from significant flooding for at least the past 10,000 years. This contrasts with existing FIRMs that include large tracts of nonflood prone land in the 100‐year and 500‐year flood hazard zones and exclude areas of indisputably flood prone land from the regulatory flood plain. From the basis of the geology, flood hazards on at least one‐third of the piedmont are mischaracterized on the regulatory maps. The formal incorporation of geologic data into flood hazard studies on desert piedmonts could significantly reduce this type of discrepancy and substantially reduce the scope, hence cost, of more elaborate engineering studies and hazard mitigation strategies. The results of this study affirm the value of new Federal Emergency Management Agency (FEMA) recommendations for characterizing alluvial fan flood hazards and support an argument for mandating geological studies in the regulatory process.  相似文献   
429.
Pollution and self-purification trends of an urban river namely, Msimbazi River, in Dar es Salaam City, Tanzania, were investigated. Site investigations and water quality analyses were done. The river is polluted in terms of high organic and nutrient concentrations, low dissolved oxygen, and high counts of indicator organisms. Biochemical oxygen demand (BOD5) concentrations were 27– 340 mg/L. Dissolved oxygen was found to be as low as 0.9 mg O2/L. Bacteriological pollution increased with distance downstream of the river, a trend attributable to an increase in the catchment of pollution sources, which are on-site sanitation systems. Although the river has an appreciable self-purification capacity, the capacity is strained by persistent pollution overloads. The pollution plight of the river is attributable to its being flanked by expanding human habitats and vibrant industrial, institutional, and socio-economic activities. Provision for pretreatment of discharges into the river is put forward as a remedial measure for the observed pollution. Matching nontechnical and techno-social remedial measures are also recommended. These include sensitization of polluters on merits of environmental protection practices such as cleaner production and strict enforcement of environmental protection laws.  相似文献   
430.
中国的地震减灾系统工程   总被引:9,自引:5,他引:9  
马宗晋 《灾害学》2005,20(2):1-5
组织不同程度不同方式的综合减灾系统,有利于一个社会单元综合对待多种紧急的灾情事务,有利于政府处理紧急事务的专业化、资源的集中运用和行政管理与指挥的专职高效.地震减灾系统工程,原则上包括四个工作领域和十个工作方面,即:监测、预测(报)、评估(专业系统);防灾、抗灾、救灾(社会公共安全系统);安置-恢复、保险-援助、立法-教育(社会保障安全系统);规划-指挥(社会组织系统).  相似文献   
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