全文获取类型
收费全文 | 215篇 |
免费 | 1篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 1篇 |
环保管理 | 7篇 |
综合类 | 141篇 |
基础理论 | 32篇 |
污染及防治 | 24篇 |
评价与监测 | 4篇 |
社会与环境 | 6篇 |
出版年
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 9篇 |
2011年 | 6篇 |
2010年 | 3篇 |
2009年 | 6篇 |
2008年 | 2篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 8篇 |
1998年 | 4篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1974年 | 3篇 |
1970年 | 4篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1967年 | 5篇 |
1966年 | 6篇 |
1965年 | 3篇 |
1964年 | 8篇 |
1963年 | 2篇 |
1962年 | 6篇 |
1961年 | 4篇 |
1960年 | 4篇 |
1959年 | 4篇 |
1958年 | 2篇 |
1957年 | 4篇 |
1956年 | 6篇 |
1955年 | 8篇 |
1954年 | 9篇 |
1953年 | 3篇 |
1952年 | 5篇 |
1950年 | 2篇 |
1948年 | 2篇 |
1943年 | 2篇 |
1941年 | 3篇 |
1936年 | 3篇 |
1930年 | 2篇 |
1928年 | 3篇 |
1924年 | 2篇 |
1920年 | 1篇 |
排序方式: 共有218条查询结果,搜索用时 773 毫秒
161.
162.
163.
164.
165.
166.
Chris Seijger Daniela Kleinschmit Dietrich Schmidt-Vogt Muhammad Mehmood-Ul-Hassan Christopher Martius 《Ambio》2021,50(12):2311
Major land use changes such as deforestation and restoration influence water resources in agriculture–forest landscapes. Changes are observed in water flows, groundwater infiltration, water quality and rainfall. Interdisciplinary water–forest research has unravelled biophysical parts of the interplay that influences forest and water resources. In this Perspective paper, we propose an expanded interdisciplinary research approach to study water and policies in agriculture–forest frontiers. The approach differs in four important aspects from previous ones: (i) a conceptual ‘frontier’ understanding; an analytical focus on (ii) agriculture and (iii) policy–water linkages; (iv) empirical attention to northern and southern countries. The approach is put into practice with the “Pendulum” framework, with interventions and the agriculture–forest frontier oscillating over time between exploitation and restoration. Through the approach, a better understanding will be provided on the dynamic interplay of water and policies in oscillating agriculture–forest frontiers, with changing outcomes for people and environment. 相似文献
167.
Kaus Andrew Schäffer Michael Karthe Daniel Büttner Olaf von Tümpling Wolf Borchardt Dietrich 《Regional Environmental Change》2017,17(7):2023-2037
Regional Environmental Change - Past and present gold mining operations scattered throughout the Kharaa River basin, Mongolia, have been identified as a major source of heavy metal and metalloid... 相似文献
168.
Time in environmental science continues to be almost neglected. In connection with rising ecological problems long-term research, as is necessary for the evaluation and prediction of environmental conditions, seems to be an exception. Complex ecosystems, e.g. terrestrial and marine systems, however, are characterized by long lasting natural time-scales which must be taken into account by analyzing them. In this context the role of time in ecosystems research becomes important. Therefore, a data base was conceptualized that could take up the main characteristics of ecosystematic analyses. Annual research reports of ecosystem research centers were revised for taking them up into the data base. In this way it is possible to evaluate the pool of data on special aspects, especially on the time parameters of the analyses. One result — besides a partial unequality of the time scales in experiment and reality — is that long-term research in terrestrial ecosystems is very rare. The reasons for this are various, but cannot divert from the need for a greater consideration of longterm observation of the ecosystems. Otherwise the ecosystematic research will not be able to meet their tasks of evaluation and prediction. 相似文献
169.
170.
Charles W. Gruber Charles E. Schumann 《Journal of the Air & Waste Management Association (1995)》2013,63(5):272-275
There is a growing interest in effects of sub-micron, nonsettling particles in the atmosphere among air pollution control agencies throughout the country. This type of pollution, generally referred to as the “soiling index” of the atmosphere, is produced primarily by the incomplete combustion of fuels. The measurement procedure has been fairly well standardized, the values being reported as Cohs or Ruds per 1000 linear feet of air. Using a similar technique, a method of quantitating smoke emission in objective terms first demonstrated by W. C. L. Hemeon in 1953, has been applied to source testing at several operating plants by the Cincinnati Division of Air Pollution Control. The source strength will be called “soiling potential” while the effect in the general atmosphere is termed “soiling index.” The soiling potential unit is Rud-ft2 per cubic foot exhaust gases or Rud-ft2 per unit of fuel input. The “Soiling Potential” sampler is described and results of tests are given. Included is the use of soiling potential in quantitating smoke emission from single sources and for constructing area wide inventory of smoke emission. The use of an area wide smoke emission inventory in Rudft2 in a simple diffusion model for calculating the soiling index (Rud-ft2/1000 cu ft) in the general atmosphere at a given point is explored. 相似文献