全文获取类型
收费全文 | 11324篇 |
免费 | 79篇 |
国内免费 | 83篇 |
专业分类
安全科学 | 283篇 |
废物处理 | 500篇 |
环保管理 | 1430篇 |
综合类 | 2459篇 |
基础理论 | 2556篇 |
环境理论 | 5篇 |
污染及防治 | 2951篇 |
评价与监测 | 685篇 |
社会与环境 | 562篇 |
灾害及防治 | 55篇 |
出版年
2022年 | 91篇 |
2021年 | 96篇 |
2019年 | 69篇 |
2018年 | 149篇 |
2017年 | 130篇 |
2016年 | 222篇 |
2015年 | 172篇 |
2014年 | 243篇 |
2013年 | 820篇 |
2012年 | 304篇 |
2011年 | 427篇 |
2010年 | 337篇 |
2009年 | 395篇 |
2008年 | 428篇 |
2007年 | 491篇 |
2006年 | 430篇 |
2005年 | 352篇 |
2004年 | 367篇 |
2003年 | 373篇 |
2002年 | 332篇 |
2001年 | 429篇 |
2000年 | 312篇 |
1999年 | 205篇 |
1998年 | 115篇 |
1997年 | 123篇 |
1996年 | 108篇 |
1995年 | 154篇 |
1994年 | 148篇 |
1993年 | 123篇 |
1992年 | 130篇 |
1991年 | 149篇 |
1990年 | 119篇 |
1989年 | 127篇 |
1988年 | 132篇 |
1987年 | 114篇 |
1986年 | 83篇 |
1985年 | 99篇 |
1984年 | 124篇 |
1983年 | 125篇 |
1982年 | 123篇 |
1981年 | 97篇 |
1980年 | 93篇 |
1979年 | 106篇 |
1978年 | 89篇 |
1977年 | 84篇 |
1976年 | 78篇 |
1975年 | 90篇 |
1974年 | 101篇 |
1972年 | 69篇 |
1965年 | 74篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
REED F. NOSS ERICA FLEISHMAN† DOMINICK A. DELLASALA‡ JOHN M. FITZGERALD§ MART R. GROSS MARTIN B. MAIN†† FIONA NAGLE‡‡ STACEY L. O'MALLEY JON ROSALES§§ 《Conservation biology》2009,23(4):825-833
Abstract: The Society for Conservation Biology (SCB) can enhance conservation of biodiversity in North America by increasing its engagement in public policy. Toward this end, the North America Section of SCB is establishing partnerships with other professional organizations in order to speak more powerfully to decision makers and taking other actions—such as increasing interaction with chapters—geared to engage members more substantively in science-policy issues. Additionally, the section is developing a North American Biodiversity Blueprint, which spans the continental United States and Canada and is informed by natural and social science. This blueprint is intended to clarify the policy challenges for protecting continental biodiversity, to foster bilateral collaboration to resolve common problems, and to suggest rational alternative policies and practices that are more likely than current practices to sustain North America's natural heritage. Conservation scientists and practitioners can play a key role by drawing policy makers' attention to ultimate, as well as proximate, causes of biodiversity decline and to the ecological and economic consequences of not addressing these threats. 相似文献
72.
Mahmoud Marwa M. Sanad Eman F. Hamdy Nadia M. 《Environmental science and pollution research international》2021,28(28):36984-37000
Environmental Science and Pollution Research - The discovery of microRNAs (miRNAs) 20 years ago has advocated a new era of “small molecular genetics.” About 2000 miRNAs are present that... 相似文献
73.
Abdelnour Sameh A. Yang Chun-Yan Swelum Ayman A. Abd El-Hack Mohamed E. Khafaga Asmaa F. Abdo Mohamed Shang Jiang-Hua Lu Yang-Qing 《Environmental science and pollution research international》2020,27(31):38472-38490
Environmental Science and Pollution Research - Global warming is considered as the main environmental stress affecting ecosystems as well as physiological and biochemical characteristics, and... 相似文献
74.
Christian Mrz Felipe S. Freitas Johan C. Faust Jasmin A. Godbold Sian F. Henley Allyson C. Tessin Geoffrey D. Abbott Ruth Airs Sandra Arndt David K. A. Barnes Laura J. Grange Neil D. Gray Ian M. Head Katharine R. Hendry Robert G. Hilton Adam J. Reed Saskia Rühl Martin Solan Terri A. Souster Mark A. Stevenson Karen Tait James Ward Stephen Widdicombe 《Ambio》2022,51(2):370
Unprecedented and dramatic transformations are occurring in the Arctic in response to climate change, but academic, public, and political discourse has disproportionately focussed on the most visible and direct aspects of change, including sea ice melt, permafrost thaw, the fate of charismatic megafauna, and the expansion of fisheries. Such narratives disregard the importance of less visible and indirect processes and, in particular, miss the substantive contribution of the shelf seafloor in regulating nutrients and sequestering carbon. Here, we summarise the biogeochemical functioning of the Arctic shelf seafloor before considering how climate change and regional adjustments to human activities may alter its biogeochemical and ecological dynamics, including ecosystem function, carbon burial, or nutrient recycling. We highlight the importance of the Arctic benthic system in mitigating climatic and anthropogenic change and, with a focus on the Barents Sea, offer some observations and our perspectives on future management and policy. 相似文献
75.
By mechanical-biological treatment (MBT) of residual municipal solid waste the behaviour of landfills can be significantly improved. After MBT the organic content (COD and BOD5), total organic carbon, and total nitrogen in the leachate, as well as the gas production rate, are reduced to values lower than 90% of the fresh untreated waste. The volume of the stabilized material to be disposed on landfills decreases enormously, by up to 70%. The monitoring effort for a landfill constructed under these conditions is reduced to a minimum and the stabilized material can be used in other ways, as material for reforestation, for cover material or for thermal utilization to produce energy. Environmental conditions are important in MBT, as well as waste characteristics. This paper describes the results of a pilot project of MBT performed in Rio de Janeiro, Brazil. The results have shown that this technology can be used successfully in developing countries, with economy for the society and important results for the environment. 相似文献
76.
Influence of dairy manure addition on the biological and thermal kinetics of composting of greenhouse tomato plant residues 总被引:2,自引:0,他引:2
A laboratory-scale bioreactor was used to investigate the influence of dairy manure addition (as an inoculum and a carbon source) on the biological and thermal kinetics of the composting process of tomato plant residues-wood shavings mixture. Urea was added (as a nitrogen source) to correct the initial C:N ratio to 30:1 and the initial moisture content was also adjusted to 60%. The result of this study indicated that manure addition to the tomato residues-wood shavings mixture is a good source of macro and micronutrients required for supporting the composting microorganisms. Manure addition increased the rate of temperature increase and the duration of maximum temperature and reduced the lag and the peak time, all of which resulted in a significant reduction in the retention time. However, thermophilic temperature (> or = 40 degrees Celsius) was only achieved with 30%, 40% and 50% manure addition for 3, 7 and 9h. Total carbon reductions were in the range of 9.4-10.8% and TKN reductions were in the range of 3.4-6.0%. Neither the nitrogen nor the moisture content were limiting factors as the C:N ratio remained in the range of 26:1 to 28:1 and the moisture content remained within the optimum range of 58-61%. The maximum temperature of each mixture correlated with the reduction of total carbon, but carbon availability was a limiting factor in these experiments. In order to attain and sustain a thermophilic phase during the composting process, the addition of a readily available carbon source to the tomato should be investigated and carbon type (carbohydrates, proteins and fats) should be taken into account. 相似文献
77.
78.
79.
80.