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661.
陈盛彬 《湖南环境生物职业技术学院学报》1997,(1)
森林旅游资源的开发与利用是当今各国森林公园建设所面临的一个重要问题。本文就如何克分利用森林旅游资源,发挥森林景观优势开展多种旅游项目,提出了自己的看法与对策,为发展我国旅游业提供了理论依据。 相似文献
662.
A model for predicting community mosaics and wildlife diversity resulting from fire disturbance to a forest ecosystem is presented. It applies an algorithm that delineates the size and shape of each patch from grid-based input data and calculates standard diversity measures for the entire mosaic of community patches and their included animal species. The user can print these diversity calculations, maps of the current community-type-age-class mosaic, and maps of habitat utilization by each animal species. Furthermore, the user can print estimates of changes in each resulting from natural disturbance. Although data and resolution level independent, the model is demonstrated and tested with data from the Lewis and Clark National Forest in Montana. 相似文献
663.
Martin Pichler Georg Guggenberger Robert Hartmann Wolfgang Zech 《Environmental science and pollution research international》1996,3(1):24-31
The behavior of 20 PAH in the organic layers of a L mull, an Of mull and a mor was assessed by a combined approach of a soil
profile study, and the analysis of particle-size separates. Increasing PAH concentrations with depth in the mor profile (L,
866 μg kg−3; Of, 2902 μg kg−1; Oh, 10489 ug kg−1) were assigned to selective enrichment during organic matter decomposition. PAH were further highly enriched within the finer
separates. For the L horizons, significant positive correlations were established between the enrichment of individual PAH
(as observed from the decomposition gradient between the >2-mm fraction and the < 0.05-mm fraction), and the KOW for each compound. The slope of the regression line, m, described the degree of differentiation between low- and high-molecular
PAH during litter decomposition. Since m was greatest in the most biologically active humus type (L mull, 0.33) and smallest
in the most inactive (mor, 0.20), microbial breakdown was assumed as the dominating process for this differentiation. The
results also indicated that decomposition processes had already taken place in the L horizons, leading to morphological and
chemical changes of organic matter, and to an enrichment of high molecular PAH. 相似文献
664.
Philip D. Gardner Hanna J. Cortner Keith F. Widaman Kathryn J. Stenberg 《Environmental management》1985,9(4):303-311
The formulation and implementation of new fire policies in the national forests depend upon public acceptance. A national survey of organized groups of forest users indicates that, contrary to the concern of many forest managers, considerable support exists for flexible fire suppression policies. Forest users are also willing to accept the risk associated with the manager's use of prescribed fire. However, important intergroup differences do exist. Such variation is discussed in relation to a number of socioeconomic variables, general fire knowledge, specific knowledge about the effects of low-intensity fires, and risk preference levels. 相似文献
665.
John F. Lehmkuhl 《Environmental management》1984,8(2):167-176
The concept of minimum populations of wildlife and plants has only recently been discussed in the literature. Population genetics has emerged as a basic underlying criterion for determining minimum population size. This paper presents a genetic framework and procedure for determining minimum viable population size and dispersion strategies in the context of multiple-use land management planning. A procedure is presented for determining minimum population size based on maintenance of genetic heterozygosity and reduction of inbreeding. A minimum effective population size (N
e
) of 50 breeding animals is taken from the literature as the minimum shortterm size to keep inbreeding below 1% per generation. Steps in the procedure adjustN
e
to account for variance in progeny number, unequal sex ratios, overlapping generations, population fluctuations, and period of habitat/population constraint. The result is an approximate census number that falls within a range of effective population size of 50–500 individuals. This population range defines the time range of short- to long-term population fitness and evolutionary potential. The length of the term is a relative function of the species generation time. Two population dispersion strategies are proposed: core population and dispersed population. 相似文献
666.
667.
遥感和GIS在森林病虫害监测管理中的应用模式 总被引:20,自引:1,他引:19
介绍了遥感技术,地理信息系统技术在森林病虫害监测管理中的应用模式,以及整个系统的集成。在整个系统中遥感用于获取森林病虫害信息,地理信息系统用于管理和处理森林病虫害信息。同时,也说明了全球定位系统可用于定位采集地面数据和导路。 相似文献
668.
王俊岭 《辽宁城乡环境科技》2009,(10):56-57
介绍了在RS的支持下,以Landsat TM和CBERS卫星影像为主要的数据来源,采用栅格数据、遥感数据与统计数据相结合的技术路线,通过目视解译、人机交互解译、计算机自动识别等遥感信息提取技术和遥感影像处理方法,得出近20a三北防护林地区林地面积的变化情况。结果表明:三北防护林地区的林地面积1986—1995年有所减小,1995年以后呈逐年增加的趋势。 相似文献
669.
Institutions play an important role in the adaptive capacity of a system in responding to climate change. This review paper
characterizes the status of the collective institutional response (government, industry, First Nation, community, civil society)
to climate change in the forest sector of the Canadian province of Ontario, and highlights the presence and nature of inter-institutional
networks as part of the response. Based on a synthesis of the commonalities in the public administration and policy literature
on tackling wicked problems, and the resilience literature, inter-institutional networks, which foster exchange of different
types of knowledge, are an important aspect of enhancing the adaptive capacity of social–ecological systems such as the forest
sector. Based on a content analysis of publicly available documents and insights gained from representatives of government,
community members and non-governmental organizations, mitigation and adaptations strategies are described. At the provincial
level there have been some new innovations in inter-institutional networks, but expansion of the forest stakeholders involved
in such networks would further enhance adaptive capacity. In particular, it is important to network with First Nations and
other forest-dependent communities who have a heightened vulnerability to climate change. The presence of a collaborative
capacity builder could foster the transfer, receipt and integration of knowledge across the networks, and ultimately build
long-term collaborative problem-solving capacity in the Ontario forest sector.
相似文献
H. Carolyn Peach BrownEmail: |
670.
Recent interest in sustainable forest management planning in the Yukon has coincided with growing public awareness of climate
change, providing an opportunity to explore how forestry plans are incorporating climate change. In this paper, the Strategic
Forest Management Plans for the Champagne and Aishihik First Nations Traditional Territory (CATT) and the Teslin Tlingit Traditional
Territory (TTTT) are examined for evidence of adaptation to climate change. For each plan, management policies and practices
that are also recognized as ways to adapt to climate change are identified to provide information on the incremental costs
and benefits of additional adaptation efforts. A typology for classifying sustainable forest management plans according to
how they address climate change is proposed and applied to the CATT and TTTT plans. This typology, which may be useful to
any future retrospective assessments on how successful these or other sustainable forest management plans have been in addressing
and managing the risks posed by climate change, consists of a matrix that categorizes plans into one of four types; (1) proactive-direct,
(2) proactive-indirect, (3) reactive-direct, and (4) reactive-indirect. Neither of the plans available for the southern Yukon
explicitly identifies climate change vulnerabilities and actions that will be taken to reduce those vulnerabilities and manage
risks. However, both plans have incorporated some examples of ‘best management practices’ for sustainable forest management
that are also consistent with appropriate climate adaptation responses. Even in a jurisdiction facing rapid ecological changes
driven by climate change, where there is a relatively high level of awareness of climate change and its implications, forestry
planning processes have yet to grapple directly with the risks that climate change may pose to the ability of forest managers
to achieve the stated goals and objectives of sustainable forest management plans.
相似文献
J. L. InnesEmail: |