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411.
Allan Curtis Bruce Shindler Angela Wright 《Journal of the American Water Resources Association》2002,38(5):1207-1216
ABSTRACT: In the last decade, watershed groups (WG) established through government initiatives have become an important part of the natural resource management landscape in developed economies. In this paper, the authors reflect upon their research and experience with Landcare in Victoria, and to a lesser extent with Watershed Councils in Oregon, to identify the principles that appear fundamental to sustaining effective WG. In the first instance, these groups must be established at a local scale using social as well as biophysical boundaries. It is also critical that WG are embedded within a supportive institutional framework that identifies realistic roles for private landowners, local organizations such as WG, and regional planning bodies. Without broad stakeholder representation, the perceived benefits of participation are quickly forfeited. It is simply unrealistic to expect an effective network of WG to be sustained without substantial investment by government to provide for program management, group coordination, and cost sharing for on‐ground work. There must also be the commitment and skills within a program to establish processes that build trust and competency amongst citizens and agencies. These principles should also provide a foundation for the critical evaluation of WG programs. 相似文献
412.
413.
Anf H. Ziadat Bruce W. Berdanier 《Journal of the American Water Resources Association》2004,40(3):631-638
ABSTRACT: Ninety‐one sediment oxygen demand (SOD) samples from six designated sites along the stretch of Lower Rapid Creek, South Dakota, were conducted using an in‐situ SOD chamber. Inside the chamber, readings of dissolved oxygen (DO), water temperature, pH, and specific conductance were recorded every minute for more than one hour using the Datasonde 3 Hydrolab. Initial readings of such parameters were recorded for the overlaying water before the deployment of the SOD chamber. Characteristics of the stream conditions, air temperature, barometric pressure, average flow velocity of the stream, depth of the stream, and the flow velocity by the chamber were recorded. Single and multiple linear regression analyses on all parameters indicated that the velocity of the stream is the least critical parameter for SOD in shallow streams. 相似文献
414.
Employees generally rate their performance more favorably than do their supervisors, which can lead to conflict and poor job performance. However, comparative international research indicates that persons from other‐oriented collectivist cultures are less self‐enhancing, suggesting that other‐oriented employees will exhibit greater agreement with ratings provided by their supervisors. We examined the effect of subordinates' other orientation on self‐supervisor performance rating agreement. Consistent with cultural expectations, self‐ratings of other‐oriented subordinates showed greater agreement with ratings provided by their supervisors and less leniency relative to their supervisors' evaluations. These findings have implications for understanding how employees in different professions, organizations, and cultures utilize feedback from their supervisors. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
415.
This article presents an analysis of the prospective costs of RCRA corrective action for private, nonfederal facilities. Two data bases developed by Research Triangle Institute and a remedial action cost model developed by CH2M Hill provide the foundation for this work. The methodology has two components, a remedial action knowledge base and a discrete-state Monte Carlo analysis. Under base case assumptions, it is estimated that the total costs of RCRA corrective action will be $240 billion, with a 5 percent chance the costs will be less than $170 billion and a 5 percent chance the costs will be more than $377 billion. 相似文献
416.
Beatrice B. Lackaff Bruce J. Hunt Ian E. Von Essen 《Journal of the American Water Resources Association》1993,29(6):949-955
ABSTRACT: U.S. Environmental Protection Agency (EPA) statutes require identification of all potential sources of contamination within a wellhead protection area. All wells over Spokane County's aquifer are included in one wellhead protection zone called the Aquifer Sensitive Area (ASA). A GIS-based Contaminant Source Inventory (CSI) was developed for the ASA. Datasets listing businesses and agencies within the ASA were imported into the GIS from state, county, city, and local agencies. These datasets were selected, joined, and sorted using GIS relational database capabilities into one ASA “business master file.” Map files were projected and transformed into common coordinates. Next, business sites within the master file were spatially related by address to the digital map files. Likely Critical Materials Users (CMU) were identified by sorting on selected standard Industrial Codes (SIC). Additional files of CMUs were imported into the Contaminant Source Inventory. GIS queries were performed to locate specific materials, quantities, and storage facilities, and to analyze CMU activity within selected buffer zones. This project demonstrated the usefulness of GIS technology in the development, management, maintenance, and analysis of vast quantities of data associated with a local wellhead protection pro. gram. 相似文献
417.
Frederick Steiner Scott Pieart Edward Cook Jacqueline Rich Virginia Coltman 《Environmental management》1994,18(2):183-201
The protection of wetlands and riparian areas has emerged as an important environmental planning issue. In the United States,
several federal and state laws have been enacted to protect wetlands and riparian areas. Specifically, the federal Clean Water
Act includes protection requirements in Sections 301 and 303 for state water quality standards, Section 401 for state certification
of federal actions (projects, permits, and licenses), and Section 404 for dredge and fill permits. The Section 401 water quality
state certification element has been called the “sleeping giant” of wetlands protection because it empowers state officials
to veto or condition federally permitted or licensed activities that do not comply with state water quality standards. State
officials have used this power infrequently. The purpose of this research was to analyze the effectiveness of state wetland
and riparian programs. Contacts were established with officials in each state and in the national and regional offices of
key federal agencies. Based on interviews and on a review of federal and state laws, state program effectiveness was analyzed.
From this analysis, several problems and opportunities facing state wetland protection efforts are presented. 相似文献
418.
Bruce L. Rhoads 《Environmental management》1986,10(1):97-106
Metropolitan areas located in arid and semiarid environments are rapidly expanding onto the piedmonts of nearby desert mountains. Hazards to urban development are posed by the complex fluvial systems that characterize these environments, yet no generally accepted methodology exists for evaluating flood hazards on desert piedmonts. An approach to flood hazard assessment is presented that involves the hydrogeomorphic analysis of land surfaces. Five flood hazard zones are identified for an area in central Arizona by analyzing the spatial variation of landforms and their associated fluvial processes. The methodology is applicable to similar environments elsewhere because it is based on the identification of forms and processes common to arid regions. The information provided by the analysis can form the basis for a comprehensive flood hazard management plan. 相似文献
419.
Bruce W. Vigon 《Journal of the American Water Resources Association》1985,21(2):179-184
Nonpoint source pollution remains as the primary reason for the designation of many of the Nation's streams as “water quality limited.” This means that even with the application of technology-based effluent limitations on point sources, ambient water quality standards will not be met. This paper explores several of the reasons why nonpoint sources are so difficult to come to grips with. These reasons include: (1) the inability to expand the definition of nonpoint sources to encompass nonengineering attributes, (2) the relatively primitive state of characterizing nonpoint sources, (3) the lack of prior success in conducting programs to study and alleviate nonpoint problems, and (4) an uncertain approach to providing incentives for control practices. 相似文献
420.