全文获取类型
收费全文 | 13596篇 |
免费 | 626篇 |
国内免费 | 4819篇 |
专业分类
安全科学 | 940篇 |
废物处理 | 848篇 |
环保管理 | 1108篇 |
综合类 | 7662篇 |
基础理论 | 2217篇 |
环境理论 | 6篇 |
污染及防治 | 4595篇 |
评价与监测 | 548篇 |
社会与环境 | 519篇 |
灾害及防治 | 598篇 |
出版年
2024年 | 10篇 |
2023年 | 224篇 |
2022年 | 672篇 |
2021年 | 572篇 |
2020年 | 437篇 |
2019年 | 409篇 |
2018年 | 549篇 |
2017年 | 636篇 |
2016年 | 594篇 |
2015年 | 788篇 |
2014年 | 1088篇 |
2013年 | 1394篇 |
2012年 | 1137篇 |
2011年 | 1303篇 |
2010年 | 937篇 |
2009年 | 932篇 |
2008年 | 971篇 |
2007年 | 771篇 |
2006年 | 721篇 |
2005年 | 536篇 |
2004年 | 382篇 |
2003年 | 468篇 |
2002年 | 400篇 |
2001年 | 326篇 |
2000年 | 347篇 |
1999年 | 403篇 |
1998年 | 336篇 |
1997年 | 319篇 |
1996年 | 302篇 |
1995年 | 264篇 |
1994年 | 181篇 |
1993年 | 160篇 |
1992年 | 115篇 |
1991年 | 95篇 |
1990年 | 65篇 |
1989年 | 55篇 |
1988年 | 44篇 |
1987年 | 19篇 |
1986年 | 22篇 |
1985年 | 12篇 |
1984年 | 12篇 |
1983年 | 11篇 |
1982年 | 10篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
1.
Zhu Rong Wang Shixin Srinivasakannan C. Li Shiwei Yin Shaohua Zhang Libo Jiang Xiaobin Zhou Guoli Zhang Ning 《Environmental Chemistry Letters》2023,21(3):1611-1626
Environmental Chemistry Letters - The demand for lithium is growing rapidly with the increase in electric vehicles, batteries and electronic equipments. Lithium can be extracted from brines, yet... 相似文献
2.
Yan Mi He Lei Prabowo Bayu Fang Zhumin Lin Jie Xu Zhang Hu Yanjun 《Journal of Material Cycles and Waste Management》2018,20(3):1594-1604
Journal of Material Cycles and Waste Management - Efforts to improve the performance of hydrothermal treatment (HT) in producing high-quality solid fuel from sewage sludge were carried out by... 相似文献
3.
Journal of Material Cycles and Waste Management - The iron ore tailing (IOT) is an industrial waste, in which large accumulations represent a serious environmental threat. To reduce the... 相似文献
4.
Land degradation is a global problem that seriously threatens human society. However, in China and elsewhere, ecological restoration still largely relies on a traditional approach that focuses only on ecological factors and ignores socioeconomic factors. To improve the effectiveness of ecological restoration and maximize its economic and ecological benefits, a more efficient approach is needed that provides support for policy development and land management and thereby promotes environmental conservation. We devised a framework for assessing the value of ecosystem services that remain after subtracting costs, such as the opportunity costs, costs of forest protection, and costs for the people who are affected by the program; that is, the net value of ecosystem services (NVES). To understand the difference between the value of a resource and the net value of the ecosystem service it provides, we used data on VES, timber sales, and afforestation costs from China's massive national afforestation programs to calculate the net value of forest ecosystem services in China. Accounting for the abovementioned costs revealed an NVES of ¥6.1 × 1012 for forests in 2014, which was 35.9% less than the value calculated without accounting for costs. As a result, the NVES associated with afforestation was 55.9% less than the NVES of natural forests. In some regions, NVES was negative because of the huge costs of human-made plantations, high evapotranspiration rates (thus, high water opportunity costs), and low forest survival rates. To maximize the ecological benefits of conservation, it is necessary to account for as many costs as possible so that management decisions can be based on NVES, thereby helping managers choose projects that maximize both economic and ecological benefits. 相似文献
5.
6.
张似松 《长江流域资源与环境》1993,2(2):155-159
分析江汉平原粮食生产的优势与问题,运用商品经济的观念,提出改革开放新形势下加快江汉平原粮食开发的设想,即依托市场,按照价值规律,科学地调整种植业比例和粮食种类结构,发展优质品种,扩大优化模式及采用高新技术等,通过优质、高产、高效,促进江汉平原粮食生产的发展。 相似文献
7.
Zhang Jing Feng Zhiming Yang Yanzhao 《中国人口.资源与环境(英文版)》2006,4(2):33-40
The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland" water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that ①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation. ②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level. ③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land. 相似文献
8.
Xiao Yali Jiang Dahe Wang Dan 《中国人口.资源与环境(英文版)》2007,5(3):51-56
Urban agglomeration of the Yangtze Delta (UAYD), one of the most developed regions of China, has witnessed an increasing prevalence in building ecological cities when the ecological cities are pursued by many modem cities, and great achievements have been made in this regard. It is inevitable, however, that certain problems exist during the construction of ecological city, which include but not limited to non-harmonious development of urban complex ecosystem, and the difficulty in quantifying eco-city construction or incomplete quantification in assessing the construction of present and future eco-city. Based on the analysis on social-economic conditions and regional conditions of the UAYD, this paper attempts to set up an index system of eco-cities combining with local characteristics, and to adopt the indices of eco-city, urban harmony, and eco-city colligate to evaluate the ecological level, urban harmonious development and eco-city construction of cities within the UAYD. Results indicate that among 15 cities in UAYD, Suzhou City ranks the highest in terms of eco-city construction, whereas Nantong ranks relatively lower; sustainable eco-city construction is possible only when cities are developed in every respect of harmony. 相似文献
9.
10.
Lei Jun & Zhang Xiaolei Xinjiang Institute of Ecology Geography Chinese Academy of Sciences Urumqi China Institute of Geography Science Natural Resources Research Chinese Academy of Sciences Beijing .China 《中国人口.资源与环境(英文版)》2005,3(3)
As a special basic economic region in China, Xinjiang is situated in the arid area in the Northwest China. Oasis agriculture is the basis of the national economy. The development of oasis agriculture helps to accelerate the development of economy, social and environment. After 50 years of practice, from 1949 to 2002, oasis agriculture in Xinjiang enhanced rapidly the scale of agricultural industry and had great changes in its structure. The amount of cultivated area rose from 120.97*102 ha t… 相似文献