全文获取类型
收费全文 | 4741篇 |
免费 | 375篇 |
国内免费 | 330篇 |
专业分类
安全科学 | 494篇 |
废物处理 | 51篇 |
环保管理 | 652篇 |
综合类 | 1883篇 |
基础理论 | 361篇 |
环境理论 | 1篇 |
污染及防治 | 200篇 |
评价与监测 | 1586篇 |
社会与环境 | 81篇 |
灾害及防治 | 137篇 |
出版年
2024年 | 14篇 |
2023年 | 79篇 |
2022年 | 133篇 |
2021年 | 138篇 |
2020年 | 188篇 |
2019年 | 122篇 |
2018年 | 97篇 |
2017年 | 130篇 |
2016年 | 171篇 |
2015年 | 221篇 |
2014年 | 277篇 |
2013年 | 328篇 |
2012年 | 347篇 |
2011年 | 366篇 |
2010年 | 254篇 |
2009年 | 277篇 |
2008年 | 184篇 |
2007年 | 266篇 |
2006年 | 251篇 |
2005年 | 235篇 |
2004年 | 179篇 |
2003年 | 234篇 |
2002年 | 150篇 |
2001年 | 140篇 |
2000年 | 119篇 |
1999年 | 102篇 |
1998年 | 70篇 |
1997年 | 82篇 |
1996年 | 62篇 |
1995年 | 44篇 |
1994年 | 37篇 |
1993年 | 43篇 |
1992年 | 16篇 |
1991年 | 17篇 |
1990年 | 15篇 |
1989年 | 13篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有5446条查询结果,搜索用时 62 毫秒
91.
92.
Much investigation supports a high incidence of disease and death rates when people live in ambient polluted air for a long time. Thus, the location of residential sites is important from a public health viewpoint. The method outlined in this paper is useful for determining the location of residential sites based on pollution sources assessment. 相似文献
93.
通过14年在环境空气质量监测中,采用连续自动采样实验分析方法,介绍了环境空气监测点位的布设、连续采样监测技术及其运行管理。 相似文献
94.
Developing Canada's National Forest Carbon Monitoring, Accounting and Reporting System to Meet the Reporting Requirements of the Kyoto Protocol 总被引:2,自引:0,他引:2
The rate of carbon accumulation in the atmosphere can be reduced by decreasing emissions from the burning of fossil fuels
and by increasing the net uptake (or reducing the net loss) of carbon in terrestrial (and aquatic) ecosystems. The Kyoto Protocol
addresses both the release and uptake of carbon. Canada is developing a National Forest Carbon Monitoring, Accounting and
Reporting System in support of its international obligations to report greenhouse gas sources and sinks. This system employs
forest-inventory data, growth and yield information, and statistics on natural disturbances, management actions and land-use
change to estimate forest carbon stocks, changes in carbon stocks, and emissions of non-CO2 greenhouse gases. A key component of the system is the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS). The model
is undergoing extensive revisions to enable analyses at four spatial scales (national, provincial, forest management unit
and stand) and in annual time steps. The model and the supporting databases can be used to assess carbon-stock changes between
1990 and the present, and to predict future carbon-stock changes based on scenarios of future disturbance rates and management
actions. 相似文献
95.
对废水污染源监测中影响监测数据代表性的主要因素进行了分析,并对提高废水污染源监测数据代表性提出了可行性建议。 相似文献
96.
The possible effects of landscape structure on starling roost distribution were investigated in western France using GIS analysis at different radii (2, 4, 8 and 10 km). Composition (11 land use classes) and configuration (patch size, diversity index) of the landscapes surrounding 97 roost sites used by starlings from 1981 to 2002 and surrounding 50 random points not used as roost sites were compared. Significant results suggested that starling roosts were established preferentially in the centre of an agricultural landscape where large units of pastures and arable land predominated and where natural areas were lacking both in large patches (forests or wetland classes) and in small patches such as woods in the mixed land class. A varied farmland landscape with natural areas and small patches should be promoted to limit the starling damage in wintering regions and also to favour their reproduction in regions where it has declined. 相似文献
97.
98.
99.
环境水质监测的质量保证 总被引:1,自引:0,他引:1
介绍了水质监测采样质量控制,环境监测实验室条件和实验室的质量保证与质量控制,并以实验室内分析COD样品为例,进一步阐述了环境水质监测中COD的控制方法,从而论证了环境水质监测质量保证和质量控制。 相似文献
100.