全文获取类型
收费全文 | 335篇 |
免费 | 3篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 4篇 |
废物处理 | 18篇 |
环保管理 | 19篇 |
综合类 | 38篇 |
基础理论 | 71篇 |
污染及防治 | 121篇 |
评价与监测 | 30篇 |
社会与环境 | 37篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 14篇 |
2020年 | 4篇 |
2019年 | 9篇 |
2018年 | 11篇 |
2017年 | 10篇 |
2016年 | 17篇 |
2015年 | 12篇 |
2014年 | 22篇 |
2013年 | 39篇 |
2012年 | 31篇 |
2011年 | 29篇 |
2010年 | 11篇 |
2009年 | 17篇 |
2008年 | 25篇 |
2007年 | 25篇 |
2006年 | 14篇 |
2005年 | 7篇 |
2004年 | 8篇 |
2003年 | 5篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有341条查询结果,搜索用时 31 毫秒
141.
142.
143.
144.
145.
Coastal and other area resources such as tidal wetlands, seagrasses, coral reefs, wetlands, and other ecosystems are often harmed by environmental damage that might be inflicted by human actions, or could occur from natural hazards such as hurricanes. Society may wish to restore resources to offset the harm, or receive compensation if this is not possible, but faces difficult choices among potential compensation projects. The optimal amount of restoration efforts can be determined by non-market valuation methods, service-to-service, or resource-to-resource approaches such as habitat equivalency analysis (HEA). HEA scales injured resources and lost services on a one-to-one trade-off basis. Here, we present the main differences between the HEA approach and other non-market valuation approaches. Particular focus is on the role of the social discount rate, which appears in the HEA equation and underlies calculations of the present value of future damages. We argue that while HEA involves elements of economic analysis, the assumption of a one-to-one trade-off between lost and restored services sometimes does not hold, and then other non-market economic valuation approaches may help in restoration scaling or in damage determination. 相似文献
146.
147.
Enrique González Ferradás Marta Doval Miñarro Isabel María Morales Terrés Francisco José Marzal Martínez 《Atmospheric environment (Oxford, England : 1994)》2010,44(21-22):2640-2645
EC Directive 2008/50/CE on ambient air quality and cleaner air for Europe specifies the obligations of Member States regarding fixed measurements of atmospheric pollutants in areas where maximum concentration levels exceed the lower assessment threshold. However, indications as to the siting of atmospheric monitoring stations are less precise and sometimes confusing. Campaigns to measure benzene and other volatile organic compounds in Murcia in 2007 and 2008 revealed that the areas where measurements coincided with the mean concentration for the whole city were always practically the same. Consequently, we propose a method for siting atmospheric monitoring stations in cities for which emission sources remain steady throughout the year, as is the case for cities in most southern European countries, where the most important emission source is traffic. The method is particularly useful for towns in which only one fixed measuring point is compulsory and should help local authorities in making correct decisions in this context. 相似文献
148.
Manuel J. Fernández-Gómez Rogelio Nogales Heribert Insam Esperanza Romero Marta Goberna 《Waste management (New York, N.Y.)》2010,30(12):2461-2468
Huge quantities of discarded fruits generated from greenhouse crops represent a worldwide environmental problem. The aim of this work was to assess the efficiency of vermicomposting as a recycling management option for biotransforming tomato-fruit wastes from greenhouses into an organic nutrient-rich product available for agricultural purposes. A pilot vermireactor was constructed. It was provided with a manure layer, where an initial population of Eisenia fetida was introduced and fed continuously at a high organic loading rate (13.6 kg TOC m?3 wk?1) for 150 days. Vermicompost chemical and enzymatic parameters as well as the bacterial and fungal community structure were determined for 210 days (vermicomposting plus a maturation period). Earthworm biomass increased after 90 days, and then declined due to increasing pH, electrical conductivity and ammonium concentration. The temporal patterns of dehydrogenase, β-glucosidase, protease and urease were related to earthworm growth and the stabilization of organic matter. Bacterial DGGE profiles differed between the period of degradation of labile substrates and the maturation step. Fungal communities at the stage of maximum earthworm biomass differed most, suggesting a gut passage effect. The end product was chemically stable and enriched in nutrients, demonstrating that tomato-fruit wastes can be successfully vermicomposted into a valuable soil amendment. We suggest continuous-feeding vermicomposting as an environmentally sound management option for greenhouse wastes. 相似文献
149.
Nymphs of the cercopid Aphrophora cribrata cover themselves with a frothy exudate while ingesting sap from their preferred host plant, the eastern white pine, Pinus strobus. Chemical analyses of froth collected from A. cribrata nymphs revealed an array of metabolites belonging to five chemical classes, including fatty acid-derived alcohols, γ-lactones
and a single 1-monoacylglycerol, as well as the polyol pinitol and the polyhydroxyalkanoate, poly-3-hydroxybutyrate. Bioassays
showed the natural A. cribata froth, as well as a synthetic mixture comprised of representative compound classes identified therein, to be repellent to
ants but largely devoid of topical irritancy in tests with cockroaches. 相似文献
150.