首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   94207篇
  免费   1234篇
  国内免费   1114篇
安全科学   3595篇
废物处理   3406篇
环保管理   14469篇
综合类   21298篇
基础理论   26939篇
环境理论   73篇
污染及防治   16675篇
评价与监测   5644篇
社会与环境   3872篇
灾害及防治   584篇
  2022年   736篇
  2021年   799篇
  2020年   655篇
  2019年   872篇
  2018年   1182篇
  2017年   1224篇
  2016年   2206篇
  2015年   1848篇
  2014年   2594篇
  2013年   9268篇
  2012年   2347篇
  2011年   2768篇
  2010年   3317篇
  2009年   3462篇
  2008年   2369篇
  2007年   2251篇
  2006年   2540篇
  2005年   2468篇
  2004年   2796篇
  2003年   2620篇
  2002年   2196篇
  2001年   2613篇
  2000年   2092篇
  1999年   1526篇
  1998年   1368篇
  1997年   1359篇
  1996年   1491篇
  1995年   1605篇
  1994年   1508篇
  1993年   1340篇
  1992年   1344篇
  1991年   1317篇
  1990年   1259篇
  1989年   1238篇
  1988年   1083篇
  1987年   1002篇
  1986年   1004篇
  1985年   1081篇
  1984年   1171篇
  1983年   1183篇
  1982年   1182篇
  1981年   1105篇
  1980年   951篇
  1979年   937篇
  1978年   833篇
  1977年   729篇
  1976年   658篇
  1974年   630篇
  1973年   656篇
  1972年   671篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
1.

Landslide poses severe threats to the natural landscape of the Lesser Himalayas and the lives and economy of the communities residing in that mountainous topography. This study aims to investigate whether the landscape change has any impact on landslide occurrences in the Kalsi-Chakrata road corridor by detailed investigation through correlation of the landslide susceptibility zones and the landscape change, and finally to demarcate the hotspot villages where influence of landscape on landslide occurrence may be more in future. The rational of this work is to delineate the areas with higher landslide susceptibility using the ensemble model of GIS-based multi-criteria decision making through fuzzy landslide numerical risk factor model along the Kalsi-Chakrata road corridor of Uttarakhand where no previous detailed investigation was carried out applying any contemporary statistical techniques. The approach includes the correlation of the landslide conditioning factors in the study area with the changes in land use and land cover (LULC) over the past decade to understand whether frequent landslides have any link with the physical and hydro-meteorological or, infrastructure, and socioeconomic activities. It was performed through LULC change detection and landslide susceptibility mapping (LSM), and spatial overlay analysis to establish statistical correlation between the said parameters. The LULC change detection was performed using the object-oriented classification of satellite images acquired in 2010 and 2019. The inventory of the past landslides was formed by visual interpretation of high-resolution satellite images supported by an intensive field survey of each landslide area. To assess the landslide susceptibility zones for 2010 and 2019 scenarios, the geo-environmental or conditioning factors such as slope, rainfall, lithology, normalized differential vegetation index (NDVI), proximity to road and land use and land cover (LULC) were considered, and the fuzzy LNRF technique was applied. The results indicated that the LULC in the study area was primarily transformed from forest cover and sparse vegetation to open areas and arable land, which is increased by 6.7% in a decade. The increase in built-up areas and agricultural land by 2.3% indicates increasing human interference that is continuously transforming the natural landscape. The landslide susceptibility map of 2019 shows that about 25% of the total area falls under high and very high susceptibility classes. The result shows that 80% of the high landslide susceptible class is contained by LULC classes of open areas, scrubland, and sparse vegetation, which point out the profound impact of landscape change that aggravate landslide occurrence in that area. The result acclaims that specific LULC classes, such as open areas, barren-rocky lands, are more prone to landslides in this Lesser Himalayan road corridor, and the LULC-LSM correlation can be instrumental for landslide probability assessment concerning the changing landscape. The fuzzy LNRF model applied has 89.6% prediction accuracy at 95% confidence level which is highly satisfactory. The present study of the connection of LULC change with the landslide probability and identification of the most fragile landscape at the village level has been instrumental in delineation of landslide susceptible areas, and such studies may help the decision-makers adopt appropriate mitigation measures in those villages where the landscape changes have mainly resulted in increased landslide occurrences and formulate strategic plans to promote ecologically sustainable development of the mountainous communities in India's Lesser Himalayas.

  相似文献   
2.
3.
Russian Journal of Ecology - In this paper, Ellenberg’s indicator values were estimated in order to soil nitrogen (N), pH (R) and soil moisture (M) in different subalpine grassland...  相似文献   
4.
Russian Journal of Ecology - A new method for assessing the response of biota to climatic changes in the ecosystem has been tested. In the Central Forest Natural Biosphere Reserve, the average...  相似文献   
5.
Environment, Development and Sustainability - Sugarcane is an industrial crop globally used for producing biofuels and bioproducts and is the only source of white sugar in Bangladesh. However,...  相似文献   
6.
Environmental Science and Pollution Research - Organic contaminants are known to affect a suite of physiological processes across vertebrate clades. However, despite their ancient lineage and...  相似文献   
7.
Environment, Development and Sustainability - Globally, traditional knowledge is at stake, notwithstanding intentions recorded in international policy conventions. Egypt has accepted and ratified...  相似文献   
8.
Russian Journal of Ecology - Climate change entails shifts in the ranges of woody plants along both latitudinal and altitudinal gradients in the boreal forest biome. In this study,...  相似文献   
9.
Environmental Science and Pollution Research - Lake Mariut Main Basin (MB) is not only one of the three basins composing Lake Mariut (LM) but is also the main source of the popular tilapia fish to...  相似文献   
10.
Environmental Science and Pollution Research - The aim of this study is to describe the existence of the inflammatory marker nuclear factor kappa light chain B lymphocyte protein (NF-?B P65)...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号