全文获取类型
收费全文 | 761篇 |
免费 | 16篇 |
国内免费 | 7篇 |
专业分类
安全科学 | 44篇 |
废物处理 | 55篇 |
环保管理 | 204篇 |
综合类 | 50篇 |
基础理论 | 190篇 |
环境理论 | 2篇 |
污染及防治 | 152篇 |
评价与监测 | 51篇 |
社会与环境 | 28篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 7篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 13篇 |
2019年 | 16篇 |
2018年 | 29篇 |
2017年 | 18篇 |
2016年 | 23篇 |
2015年 | 22篇 |
2014年 | 30篇 |
2013年 | 55篇 |
2012年 | 34篇 |
2011年 | 48篇 |
2010年 | 43篇 |
2009年 | 30篇 |
2008年 | 47篇 |
2007年 | 56篇 |
2006年 | 38篇 |
2005年 | 22篇 |
2004年 | 25篇 |
2003年 | 26篇 |
2002年 | 25篇 |
2001年 | 10篇 |
2000年 | 13篇 |
1999年 | 14篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 12篇 |
1995年 | 12篇 |
1994年 | 10篇 |
1993年 | 10篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1971年 | 2篇 |
排序方式: 共有784条查询结果,搜索用时 109 毫秒
71.
72.
73.
Timothy Heeren Robert A. Smith Suzette Morelock Ralph W. Hingson 《Journal of Safety Research》1985,16(3):127-134
The problem of alcohol-related highway fatalities has led a majority of states to enact new legislative countermeasures. Because few states consistently collect information on alcohol involvement in fatal crashes, the evaluation of the effectiveness of these countermeasures has relied on surrogate measures of alcohol involvement. Using data from the U.S. Department of Transportation's Fatal Accident Reporting System (FARS), this study addresses the following questions: (a) Which of the several surrogate measures used are most likely to reflect alcohol involvement in fatal crashes? and (b) Do the trends in these surrogate measures provide an accurate appraisal of the true trends in alcohol-involved fatal crashes? The authors conclude that nighttime fatal crashes are the best surrogate measure of alcohol-involved crashes, but that surrogate measures may not accurately mirror trends in alcohol-involved fatal crashes over time, particularly in small states or over short durations. All drivers in fatal crashes should be given blood alcohol level (BAL) tests to most accurately assess the effects of drunk driving countermeasures. 相似文献
74.
Alireza A. Shamshirsaz Kelsey A. Stewart Hadi Erfani Ahmed A. Nassr Nathan C. Sundgren Amy R. Mehollin-Ray Shaine A. Morris Jimmy Espinoza Magdalena Sanz Cortes Christopher Cassady Timothy C. Lee Eumenia C. Castro Olutoyin A. Olutoye Deepak K. Mehta Darrell Cass Oluyinka O. Olutoye Michael A. Belfort 《黑龙江环境通报》2019,39(4):287-292
75.
Genevieve Briand Eric C. Schuck David W. Holland 《Journal of the American Water Resources Association》2008,44(2):360-366
Abstract: For over 10 years, several species of salmon have been identified as either threatened or endangered in the Snake River Basin of Idaho. The United States Bureau of Reclamation, in cooperation with the National Marine Fisheries Service, has proposed a variety of plans to increase stream flows in the Snake River Basin to facilitate movement by juvenile salmon smolts to the ocean. This research examines two of the flow augmentation plans proposed by the Bureau of Reclamation as well as two alternative plans, one founded purely on existing priority‐based water rights and another geared toward minimizing the effects of flow augmentations on farms profitability. Results from a basin‐wide model of agricultural production in the Snake River Basin, the Snake River Agricultural Model, present evidence that (1) older water rights are used towards production of less valuable crops, (2) flow augmentation scenarios have unequal effects on farms profitability across agricultural regions within the basin, and (3) irrigation water is valued from US$4 to US$59 an acre‐foot. 相似文献
76.
Employment liability is an important check and balance against employee harm at work. In practice, however, an inadvertent consequence of employment liability is a potential shift in power from organizations to employees that affects subsequent managerial decision making. In this Incubator, we discuss behavioral and attitudinal ramifications of employment liability at work. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
77.
78.
Sullivan TJ Moore JA Thomas DR Mallery E Snyder KU Wustenberg M Wustenberg J Mackey SD Moore DL 《Environmental management》2007,40(6):958-965
An experimental study was conducted in Tillamook, Oregon, USA, to quantify the effectiveness of edge-of-field vegetated buffers
for reducing transport of fecal coliform bacteria (FCB) from agricultural fields amended with dairy cow manure. Installation
of vegetated buffers on loamy soils dramatically reduced the bacterial contamination of runoff water from manure-treated pasturelands,
but the size of the vegetated buffer was not an important determinant of bacterial removal efficiency. Only 10% of the runoff
samples collected from treatment cells having vegetated buffers exhibited FCB concentrations >200 colony forming units (cfu)/100
mL (a common water quality standard value), and the median concentration for all cells containing vegetated buffers was only
6 cfu/100 mL. The presence of a vegetated buffer of any size, from 1 to 25 m, generally reduced the median FCB concentration
in runoff by more than 99%. Results for FCB load calculations were similar. Our results suggest that where substantial FCB
contamination of runoff occurs from manure-treated pasturelands, it might be disproportionately associated with specific field
or management conditions, such as the presence of soils that exhibit low water infiltration and generate larger volumes of
runoff or the absence of a vegetated buffer. Buffer size regulations that do not consider such differences might not be efficient
or effective in reducing bacterial contamination of runoff. 相似文献
79.
Yellow starthistle (Centaurea solsitialis L.) is an invasive weed that creates problems for the management of Idaho's rangelands. A bioeconomic approach combined with an input-output economic model is used to estimate direct and secondary economic costs of the weed in relation to its interference with agricultural and non-agricultural benefits that rangelands provide. Direct economic costs of the infestations were estimated to be of 8.2 million '05 dollars per year, and secondary costs of 4.5 million '05 dollars per year, for a total of 12.7 million '05 dollars; agricultural related economic impacts accounted for 79% of this total cost, and non-agricultural for 21%. 相似文献
80.
Michael M. Pollock Timothy J. Beechie 《Journal of the American Water Resources Association》2014,50(3):543-559
Intact riparian ecosystems are rich in biological diversity, but throughout the world, many have been degraded. Biodiversity declines, particularly of vertebrates, have led to experimental efforts to restore riparian forests by thinning young stands to accelerate creation of large diameter live trees. However, many vertebrates depend on large diameter deadwood that is standing as snags or fallen to the forest floor or fallen into streams. Therefore, we reviewed the sizes of deadwood and live trees used by different vertebrate species to understand which species are likely to benefit from different thinning treatments. We then examined how riparian thinning affects the long‐term development of both large diameter live trees and deadwood. To this end, we used a forest growth model to examine how different forest thinning intensities might affect the long‐term production and abundance of live trees and deadwood. Our results suggest that there are long‐term habitat tradeoffs associated with different thinning intensities. Species that utilize large diameter live trees will benefit most from heavy thinning, whereas species that utilize large diameter deadwood will benefit most from light or no thinning. Because far more vertebrate species utilize large deadwood rather than large live trees, allowing riparian forests to naturally develop may result in the most rapid and sustained development of structural features important to most terrestrial and aquatic vertebrates. 相似文献