全文获取类型
收费全文 | 854篇 |
免费 | 17篇 |
国内免费 | 62篇 |
专业分类
安全科学 | 78篇 |
废物处理 | 11篇 |
环保管理 | 194篇 |
综合类 | 210篇 |
基础理论 | 85篇 |
环境理论 | 1篇 |
污染及防治 | 108篇 |
评价与监测 | 34篇 |
社会与环境 | 66篇 |
灾害及防治 | 146篇 |
出版年
2023年 | 11篇 |
2022年 | 14篇 |
2021年 | 13篇 |
2020年 | 27篇 |
2019年 | 15篇 |
2018年 | 18篇 |
2017年 | 26篇 |
2016年 | 24篇 |
2015年 | 29篇 |
2014年 | 19篇 |
2013年 | 42篇 |
2012年 | 26篇 |
2011年 | 54篇 |
2010年 | 33篇 |
2009年 | 46篇 |
2008年 | 55篇 |
2007年 | 44篇 |
2006年 | 37篇 |
2005年 | 26篇 |
2004年 | 26篇 |
2003年 | 42篇 |
2002年 | 26篇 |
2001年 | 23篇 |
2000年 | 22篇 |
1999年 | 14篇 |
1998年 | 20篇 |
1997年 | 27篇 |
1996年 | 36篇 |
1995年 | 32篇 |
1994年 | 17篇 |
1993年 | 23篇 |
1992年 | 16篇 |
1991年 | 8篇 |
1990年 | 10篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有933条查询结果,搜索用时 15 毫秒
891.
van Breukelen BM Röling WF Groen J Griffioen J van Verseveld HW 《Journal of contaminant hydrology》2003,65(3-4):245-268
The biogeochemical processes were identified which improved the leachate composition in the flow direction of a landfill leachate plume (Banisveld, The Netherlands). Groundwater observation wells were placed at specific locations after delineating the leachate plume using geophysical tests to map subsurface conductivity. Redox processes were determined using the distribution of solid and soluble redox species, hydrogen concentrations, concentration of dissolved gases (N(2), Ar, and CH(4)), and stable isotopes (delta15N-NO(3), delta34S-SO(4), delta13C-CH(4), delta2H-CH(4), and delta13C of dissolved organic and inorganic carbon (DOC and DIC, respectively)). The combined application of these techniques improved the redox interpretation considerably. Dissolved organic carbon (DOC) decreased downstream in association with increasing delta13C-DOC values confirming the occurrence of degradation. Degradation of DOC was coupled to iron reduction inside the plume, while denitrification could be an important redox process at the top fringe of the plume. Stable carbon and hydrogen isotope signatures of methane indicated that methane was formed inside the landfill and not in the plume. Total gas pressure exceeded hydrostatic pressure in the plume, and methane seems subject to degassing. Quantitative proof for DOC degradation under iron-reducing conditions could only be obtained if the geochemical processes cation exchange and precipitation of carbonate minerals (siderite and calcite) were considered and incorporated in an inverse geochemical model of the plume. Simulation of delta13C-DIC confirmed that precipitation of carbonate minerals happened. 相似文献
892.
Energy analysis of nonmarket values of the Mississippi Delta 总被引:1,自引:0,他引:1
An energy analysis was used to estimate nonmarket values under various land cover scenarios in the Mississippi Delta. Land
loss since 1900 has led to a decline in nonmarket values from $3.1 billion/year in 1900 to $2.5 billion in 1990, resulting
in a total loss of $29.4 billion. This loss is concentrated in the Barataria-Terrebonne basins, where nonmarket value has
dropped from $1.6 billion/year in 1956 to $1.3 billion/year in 1988. Although values are projected to increase in the Atchafalaya
basin (from $723 million/year in 1988 to $756 million/year in 2058), total nonmarket value for the Louisiana coast is projected
to decrease to $2.1 billion/year under currently approved levels of restoration. 相似文献
893.
Contemporary approaches to natural resources and environmental decision-making typically draw on a “systems” perspective to
assess and improve management strategies. This paper describes the early genesis of the systems analysis approach. It concentrates
on a period between the mid-19th to early 20th centuries. During the early part of this period, George Marsh's Man and Nature and related works laid out an approach to problem-solving that recognized the relationship among physically disperse elements
in the environment, the need to balance benefits against costs, the potential for using quantitative modeling to understand
management options, and the importance of integrating human and natural components into solutions. In the early 20th century,
the Miami Conservancy District project brought this approach to fruition with its use of complex simulation and optimization
modeling, detailed cost–benefit analysis, and its linking of economics, engineering, science, and law into a far-reaching
solution to a complex water resources problem. The objective of this paper is to describe the early development and application
of this conceptual approach to problem-solving. An examination of the origins of natural resources systems analysis can broaden
one's perspective of the contemporary field to understand its roots as a philosophy for environmental problem-solving. 相似文献
894.
自然灾害综合性评价与分区是防、减、治灾的基础。本文提出的自然灾害综合评价模型,考虑了各种自然灾害的共同作用和受灾区域的社会经济水平,用自然灾害综合指数来表示区域自然灾害的危险程度,并据此作综合分区。 相似文献
895.
896.
根据陕西解放以来的灾害损失资料,将各种灾害造成的成灾面积、人口死亡、房屋倒塌和水、旱、风雹、病虫害、霜冻以及其它灾害造成的农田成灾面积分成4和5个档次,用人工神经网络方法进行聚类,可分成5个不同的灾害损失组合年,其代表了不同损失特点,有助于对各年定量评价灾害年景。分析这些不同损失组合类型的降水特征,可通过对降水的预报来预测可能出现的灾害组合,从而为重点防御某种或某几种灾害损失指明方向。 相似文献
897.
Risk and vulnerability indicators at different scales:: Applicability, usefulness and policy implications 总被引:13,自引:0,他引:13
This paper outlines selected approaches to measuring risk and vulnerability to hazards of natural origin using indicators and indices. It discusses their applicability, usefulness and policy implications. Indicators and indices have been developed on different scales and for different purposes. The paper will briefly introduce three global approaches to disaster-risk identification and will juxtapose them with one local approach in order to examine the differences concerning the functions and the purpose of the assessment as well as their impact for policy development. In contrast to an earlier comparative analysis of the three global disaster-risk indicator programmes by Mark Pelling in 2004, which focused primarily on the methodologies used, this paper places more emphasis on aspects of applicability and policy implications and outlines challenges and limitations of the different approaches. Since the assessment and mapping of human vulnerability is less developed than hazard assessment work [Pelling M., 2004. Visions of Risk: A Review of International Indicators of Disaster Risk and its Management. UNDP—Bureau for Crisis Prevention and Recovery (BRCP), Geneva], this paper focuses in greater depth on how the approaches capture vulnerability. Conclusions will be formulated on how to further enhance vulnerability identification, particularly at the sub-national level. 相似文献
898.
自然中心主义环境伦理思想作为目前最为热门的学科之一,自然同其它学科一样,有它产生的思想根源、现实缘由和直接的动因。工业社会的精神失落和蓬勃兴起的绿色运动是其思想诱因与直接动因,而它形成的现实缘由则主要是全球面临的生态困境以及对人与自然关系的重新认识。 相似文献
899.
900.
Christian Kuhlicke Annett Steinführer Chloe Begg Chiara Bianchizza Michael Bründl Matthias Buchecker Bruna De Marchi Marina Di Masso Tarditti Corina Höppner Bla? Komac Louis Lemkow Jochen Luther Simon McCarthy Luigi Pellizzoni Ortwin Renn Anna Scolobig Meera Supramaniam Sue Tapsell Gisela Wachinger Gordon Walker Rebecca Whittle Matija Zorn Hazel Faulkner 《Environmental Science & Policy》2011,14(7):804-814
Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated. 相似文献