全文获取类型
收费全文 | 1096篇 |
免费 | 30篇 |
国内免费 | 24篇 |
专业分类
安全科学 | 51篇 |
环保管理 | 263篇 |
综合类 | 457篇 |
基础理论 | 147篇 |
环境理论 | 1篇 |
污染及防治 | 57篇 |
评价与监测 | 115篇 |
社会与环境 | 46篇 |
灾害及防治 | 13篇 |
出版年
2024年 | 3篇 |
2023年 | 11篇 |
2022年 | 12篇 |
2021年 | 24篇 |
2020年 | 54篇 |
2019年 | 12篇 |
2018年 | 14篇 |
2017年 | 31篇 |
2016年 | 36篇 |
2015年 | 25篇 |
2014年 | 48篇 |
2013年 | 41篇 |
2012年 | 38篇 |
2011年 | 74篇 |
2010年 | 41篇 |
2009年 | 86篇 |
2008年 | 58篇 |
2007年 | 64篇 |
2006年 | 60篇 |
2005年 | 37篇 |
2004年 | 33篇 |
2003年 | 52篇 |
2002年 | 47篇 |
2001年 | 29篇 |
2000年 | 41篇 |
1999年 | 35篇 |
1998年 | 25篇 |
1997年 | 13篇 |
1996年 | 13篇 |
1995年 | 21篇 |
1994年 | 8篇 |
1993年 | 19篇 |
1992年 | 13篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1977年 | 1篇 |
排序方式: 共有1150条查询结果,搜索用时 828 毫秒
141.
Assessing Land-Use Impacts on Natural Resources 总被引:3,自引:1,他引:2
V. H. Dale A. W. King L. K. Mann R. A. Washington-Allen R. A. McCord 《Environmental management》1998,22(2):203-211
/ Much information is available on changes that occur in natural resources from both spatially-explicit data on environmental conditions and models of the interactions of these conditions and resources with human activities. The strategy for assessing land-use impacts on natural resources developed in this paper provides a framework for using relevant data and models to address questions of how management practices can promote both use and protection of resources. This assessment strategy integrates spatially explicit environmental data using geographic information systems (GIS) with computer models that simulate changes in land cover in response to land-use impacts. The computer models also simulate susceptibility of species to changes in habitat suitability and landscape patterns. The approach is applied to management of limestone barrens on the Oak Ridge Reservation in East Tennessee. Potential limestone barrens habitats are identified by overlaying appropriate soils, geology, slope, and land-use/land-cover conditions. Their validity is tested against known sites containing rare species that occur in these habitats. The location of habitats at risk in the aftermath of human activities is determined by using an available area model that identifies the size and proximity of sites that particular types of species can no longer use as habitat. The resulting risk map can be used in land management planning. The approach uses readily available in situ and remotely sensed data and is applicable to a wide range of locations and land-use scenarios. This approach can be refined based on needs identified by land managers and on the sensitivity of the results to the resolution of available resource information.KEY WORDS: Land management; Assessment; Habitat characterization; Limestone barrens; Ecological modeling; Geographic information systems 相似文献
142.
143.
144.
Amanda Machin 《环境政策》2019,28(2):208-227
ABSTRACTOver the last three decades, ecological modernisation (EM) has emerged as a powerful political discourse, in which economic growth, environmental protection and energy security are mutually reinforcing. Here, the trajectory of EM in the European Union is traced, using a discourse analysis of the seven Environmental Action Programmes. The discourse articulated in these documents points towards an encroaching ‘double depoliticisation’. First, political decisions are discursively constructed as a matter of market rationality rather than a democratic process that engages with different political positions. Second, EM is reified as the only feasible solution, and alternative and contesting discourses are marginalised. Thus not only are political differences erased from the discourse, but the discourse is itself removed from political debate. 相似文献
145.
Brock TC Crum SJ Deneer JW Heimbach F Roijackers RM Sinkeldam JA 《Environmental pollution (Barking, Essex : 1987)》2004,130(3):411-426
Three different risk assessment procedures are described that aim to protect freshwater habitats from risks of the photosynthesis-inhibiting herbicides metribuzin and metamitron. These procedures are (1) the first-tier approach, based on standard toxicity tests and the application of an assessment factor, (2) the Species Sensitivity Distribution (SSD) approach, based on laboratory tests with a wider array of species and the application of a statistical model to calculate the HCx (the Hazardous Concentration for x% of the species), and (3) the model ecosystem approach, based on the evaluation of treatment-related effects in field enclosures. A comparison of the risk assessment procedures reveals that the first-tier approach is the most conservative for metamitron and metribuzin, and that HC5 values (and even HC10 values) based on acute EC50 values of algae and aquatic vascular plants may be used to derive maximum permissible concentrations for single applications. For both compounds these HC5 values were very similar to the ecological threshold concentrations in the enclosure studies. In contrast to model ecosystem experiments, however, HCx values based on lab toxicity tests do not provide information on the recovery potential of sensitive endpoints and on indirect effects, which may be important for regulatory decision-making. In the enclosure study, indirect effects of metribuzin on invertebrate populations were observed at an exposure concentration that was approximately 20 times lower than the corresponding HC5 value based on lab toxicity data for aquatic invertebrates. 相似文献
146.
农药毒死蜱的生态风险及其微生物修复技术研究进展 总被引:11,自引:0,他引:11
毒死蜱是替代甲胺磷和对硫磷等高毒农药的高效有机磷杀虫剂,在世界范围得到广泛使用.但是,环境毒理学研究发现,毒死蜱对生态环境具有潜在的危险性,甚至被认为具有干扰内分泌的功能,许多国家对毒死蜱在农产品中的残留量有严格的规定.因此,深入研究毒死蜱的生态风险问题是当务之急.对国内外关于毒死蜱的残留活性、生态毒理、降解机制以及生物修复等方面的研究进行了综述,以期对毒死蜱的合理管理和使用提供科学依据. 相似文献
147.
选择我国不同地域6条铁路,现场调查铁路取土、弃土(渣)场的使用及恢复情况,从取弃土场的占地面积及类型、取土量、弃土量等方面分析了其利用现状,并对植被恢复效果和难易程度进行了讨论。调查表明:北方平原区、荒漠区铁路的取土量较多,南部丘陵区的弃土(渣)场及弃渣量较多。从恢复效率和程度看,南部地区植被恢复相对容易且在1年内可以恢复到较好程度,但植被恢复不到位,较易发生水土流失等次生灾害;东北、华北地区植被恢复2年左右可以恢复至良好程度;西北地区植被恢复需求较小;对于部分高原地区,海拔越低、降雨越多,恢复越好,但部分地区降雨量是生态恢复的首要制约因子,保水措施是这类地区生态恢复的重点。 相似文献
148.
149.
150.
拜泉县生态环境建设与效果分析 总被引:1,自引:0,他引:1
拜泉县在农业生态建设中,坚持科学发展观,走可持续发展之路,狠抓生态环境建设,三十多年如一日,治理穷山恶水,重整拜泉山河。通过对拜泉县生态环境历史和现状的介绍,生态建设的效果分析,得出生态环境的有效保护、合理开发是农业可持续发展的保证。 相似文献