全文获取类型
收费全文 | 1108篇 |
免费 | 43篇 |
国内免费 | 25篇 |
专业分类
安全科学 | 56篇 |
废物处理 | 63篇 |
环保管理 | 299篇 |
综合类 | 102篇 |
基础理论 | 298篇 |
环境理论 | 4篇 |
污染及防治 | 219篇 |
评价与监测 | 77篇 |
社会与环境 | 49篇 |
灾害及防治 | 9篇 |
出版年
2023年 | 14篇 |
2022年 | 14篇 |
2021年 | 17篇 |
2020年 | 24篇 |
2019年 | 16篇 |
2018年 | 43篇 |
2017年 | 45篇 |
2016年 | 64篇 |
2015年 | 47篇 |
2014年 | 44篇 |
2013年 | 85篇 |
2012年 | 64篇 |
2011年 | 89篇 |
2010年 | 52篇 |
2009年 | 57篇 |
2008年 | 58篇 |
2007年 | 64篇 |
2006年 | 49篇 |
2005年 | 32篇 |
2004年 | 44篇 |
2003年 | 34篇 |
2002年 | 30篇 |
2001年 | 14篇 |
2000年 | 18篇 |
1999年 | 17篇 |
1998年 | 18篇 |
1997年 | 19篇 |
1996年 | 14篇 |
1995年 | 8篇 |
1994年 | 3篇 |
1993年 | 12篇 |
1992年 | 9篇 |
1991年 | 9篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 8篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 6篇 |
1978年 | 2篇 |
1976年 | 1篇 |
排序方式: 共有1176条查询结果,搜索用时 31 毫秒
991.
Heida L. Diefenderfer Kathryn L. Sobocinski Ronald M. Thom Christopher W. May Amy B. Borde Susan L. Southard John Vavrinec Nichole K. Sather 《Environmental management》2009,44(4):712-731
Planners are being called on to prioritize marine shorelines for conservation status and restoration action. This study documents
an approach to determining the management strategy most likely to succeed based on current conditions at local and landscape
scales. The conceptual framework based in restoration ecology pairs appropriate restoration strategies with sites based on
the likelihood of producing long-term resilience given the condition of ecosystem structures and processes at three scales:
the shorezone unit (site), the drift cell reach (nearshore marine landscape), and the watershed (terrestrial landscape). The
analysis is structured by a conceptual ecosystem model that identifies anthropogenic impacts on targeted ecosystem functions.
A scoring system, weighted by geomorphic class, is applied to available spatial data for indicators of stress and function
using geographic information systems. This planning tool augments other approaches to prioritizing restoration, including
historical conditions and change analysis and ecosystem valuation. 相似文献
992.
Christopher K. Metcalf Shawn D. Wilkerson William A. Harman 《Journal of the American Water Resources Association》2009,45(5):1260-1272
Abstract: Regional curves, which relate bankfull channel dimensions and discharge to watershed drainage area, are developed to aid in identifying the bankfull stage in ungaged watersheds, and estimating the bankfull discharge and dimensions for river studies and natural channel design applications. This study assessed 26 stable stream reaches in two hydro‐physiographic regions of the Florida Coastal Plain: the Northwest Florida Coastal Plain (NWFCP) and the North Florida Coastal Plain (NFCP). Data from stream reaches in Georgia and Alabama were also used to develop the Florida regional curves, since they are located in the same hydro‐physiographic region. Reaches were selected based on the presence of U.S. Geological Survey gage stations and indicators of limited watershed development (e.g., <10% impervious surface). Analyses were conducted to determine bankfull channel dimensions, bankfull discharge, average channel slope, and Rosgen stream classification. Based on these data, significant relationships were found between bankfull cross‐sectional area, width, mean depth, and discharge as a function of drainage area for both regions. Data from this study suggested that bankfull discharges and channel dimensions were larger from NWFCP streams than from Coastal Plain streams in North Carolina and Maryland. Bankfull discharges were similar between NFCP and Georgia coastal plain streams; therefore, the data were combined into one regional curve. In addition, the data were stratified by Rosgen stream type. This stratification strengthened the relationships of bankfull width and mean depth as a function of drainage area. 相似文献
993.
994.
Cadle SH Ayala A Black KN Fulper CR Graze RR Minassian F Murray HB Natarajan M Tennant CJ Lawson DR;Coordinating Research Council 《Journal of the Air & Waste Management Association (1995)》2007,57(2):139-145
The Coordinating Research Council held its 16th workshop in March 2006, with 83 presentations describing the most recent mobile source-related emissions research. In this paper, we summarize the presentations from researchers who are engaged in improving our understanding of the contribution of mobile sources to air quality. Participants in the workshop discussed evaluation of in-use emissions control programs, effects of fuels on emissions, emission models and emission inventories, results from gas- and particle-phase emissions studies from spark-ignition and diesel-powered vehicles, and efforts to improve our capabilities in performing on-board emissions measurements, as well as topics for future research. 相似文献
995.
Lewis MA Dantin DD Chancy CA Abel KC Lewis CG 《Environmental pollution (Barking, Essex : 1987)》2007,146(1):206-218
Contaminant concentrations were determined for media associated with 13 Florida seagrass beds. Concentrations of 10 trace metals were more commonly detected in surface water, sediment and two seagrass species than PAHs, pesticides and PCBs. Concentrations of copper and arsenic in surface water exceeded Florida aquatic life criteria more frequently than other trace elements. Total organic carbon, mercury, chromium, zinc, total chlordane, total PAHs, total PCBs, DDD and DDE were significantly greater in seagrass-rooted sediments than adjacent non-vegetated sediments. Total DDT, DDD, DDE, total chlordane, arsenic, copper and nickel exceeded proposed sediment quality guidelines at six of 13 grass beds. Pesticides, PAHs, and PCBs were below detection in seagrass tissues. Mercury, cadmium, nickel, lead and silver were detected in 50% or more of the tissues for Thalassia testudinum (turtle grass) and Halodule wrightii (shoal grass). Spatial, interspecific and tissue differences were usually an order of magnitude or less. 相似文献
996.
Unrine JM Hopkins WA Romanek CS Jackson BP 《Environmental pollution (Barking, Essex : 1987)》2007,149(2):182-192
Despite the influence that amphibians have on the flow of energy and nutrients in ecological systems, the role that amphibians play in transporting contaminants through food webs has received very little attention. This study was undertaken to investigate bioaccumulation of trace elements in amphibians relative to other small aquatic organisms in a contaminated wetland. We collected bullfrog larvae (Rana catesbeiana) along with three other species of small vertebrates and four species of invertebrates from a site contaminated with a wide array of trace elements and analyzed them for trace element concentrations and stable nitrogen and carbon isotope composition. We found that amphibian larvae accumulated the highest concentrations of most trace elements, possibly due to their feeding ecology. These results suggest that omnivorous amphibian larvae can serve as a critical link for trace element trophic transfer. Their propensity to accumulate trace elements may have important implications for amphibian health in contaminated environments and should be further investigated. 相似文献
997.
998.
Ecological communities typically change along gradients of human impact, although it is difficult to estimate the footprint of impacts for diffuse threats such as pollution. We developed a joint model (i.e., one that includes multiple species and their interactions with each other and environmental covariates) of benthic habitats on lagoonal coral reefs and used it to infer change in benthic composition along a gradient of distance from logging operations. The model estimated both changes in abundances of benthic groups and their compositional turnover, a type of beta diversity. We used the model to predict the footprint of turbidity impacts from past and recent logging. Benthic communities far from logging were dominated by branching corals, whereas communities close to logging had higher cover of dead coral, massive corals, and soft sediment. Recent impacts were predicted to be small relative to the extensive impacts of past logging because recent logging has occurred far from lagoonal reefs. Our model can be used more generally to estimate the footprint of human impacts on ecosystems and evaluate the benefits of conservation actions for ecosystems. 相似文献
999.
Otto Ilona M. Reckien Diana Reyer Christopher P. O. Marcus Rachel Le Masson Virginie Jones Lindsey Norton Andrew Serdeczny Olivia 《Regional Environmental Change》2017,17(6):1651-1662
Regional Environmental Change - This article provides a review of recent scientific literature on social vulnerability to climate change, aiming to determine which social and demographic groups,... 相似文献
1000.