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291.
Mountain watersheds, comprising a substantial proportion of national territories of countries in mainland South and Southeast Asia, are biophysical and socioeconomic entities, regulating the hydrological cycle, sequestrating carbon dioxide, and providing natural resources for the benefit of people living in and outside the watersheds. A review of the literature reveals that watersheds are undergoing degradation at varying rates caused by a myriad of factors ranging from national policies to farmers' socioeconomic conditions. Many agencies—governmental and private—have tried to address the problem in selected watersheds. Against the backdrop of the many causes of degradation, this study examines the evolving approaches to watershed management and development. Until the early 1990s, watershed management planning and implementation followed a highly centralized approach focused on heavily subsidized structural measures of soil conservation, planned and implemented without any consultation with the mainstream development agencies and local people. Watershed management was either the sole responsibility of specially created line agencies or a project authority established by external donors. As a consequence, the initiatives could not be continued or contribute to effective conservation of watersheds. Cognizant of this, emphasis has been laid on integrated, participatory approaches since the early 1990s. Based on an evaluation of experiences in mainland South and Southeast Asia, this study finds not much change in the way that management plans are being prepared and executed. The emergence of a multitude of independent watershed management agencies, with their own organizational structures and objectives and planning and implementation systems has resulted in watershed management endeavors that have been in complete disarray. Consistent with the principle of sustainable development, a real integrated, participatory approach requires area-specific conservation programs that are well incorporated into integrated socioeconomic development plans prepared and implemented by local line agencies in cooperation with nongovernment organizations (NGOs) and concerned people.  相似文献   
292.
Why the Conservation of Forest Genetic Resources Has Not Worked   总被引:3,自引:0,他引:3  
Abstract:  Genetic diversity is indispensable for long-term forest sustainability and is therefore mentioned in numerous binding and nonbinding political covenants calling for action. Nevertheless, there are significant obstacles to the conservation of forest genetic resources. We discuss hindrances to genetic conservation, mainly in Europe. We identified impediments by reviewing the literature and on the basis of the experiences of the authors in this field and their participation in related political processes. The impediments include (1) difficulties in assessing and monitoring genetic erosion and human impacts (e.g., by the lack of markers showing adaptive variation and the lack of record keeping on the use and transfer of forest-tree germplasm), (2) complexities of European national structures that make the development of a common strategy toward forest genetic conservation problematic, (3) lack of effective forest governance in many parts of the world, (4) the general unattractiveness of genes as flagships in raising public awareness, (5) lack of integration of genetic aspects into biodiversity conservation, and (6) the fact that scientists and politicians are often at cross-purposes. To overcome these impediments, forest geneticists and their peers in species conservation have to participate more actively in decision making. In doing so, they must be prepared to face challenges on 2 fronts: participating in political processes and the provision of significant research findings to ensure that decisions with respect to forest genetic diversity are politically implementable and effectively address targets.  相似文献   
293.
What supports the adaptive capacity of watershed governance? Using document review, interviews, and network diagrams, we analyze how structural attributes of a governance network emerged and co-evolved with changes in biophysical conditions in a case study of a small watershed in northeast Ohio. Results indicate that the network governance structure that emerged evolved to become a hybrid of two different structural forms that diversified stakeholder engagement, generated social capital, improved social learning, and stimulated change in management practices, all of which have enhanced adaptive capacity. A significant challenge to adaptive capacity arises, however, as network governance has come to rely significantly on a centralized organization to broker relationships for information and other resources.  相似文献   
294.
An important consideration for any new nuclear build programme is an understanding of the public's viewpoint, as in many countries this can influence the direction of future energy markets. This paper presents a first attempt at understanding public views on the design of new nuclear plants. A survey of 1304 adults in the UK was carried out using a questionnaire developed in this research. The study suggests that the general public are willing and able to express preferences for design aspects of nuclear power plants and that meaningful information can be obtained to inform designers. Responses indicate that public preferences are consistent with current design practice for nuclear power plants. Further analysis reveals that public preferences related to plant design are not influenced strongly by their existing attitudes. Our findings contribute to the literature on the governance of energy supply technologies and the involvement of the public in the innovation process. We argue that involving the public in the design of nuclear power plants is an important aspect of a more transparent, participatory approach intended to improve trust in the governance of future energy supply options.  相似文献   
295.
Although Dutch cities were among the forerunners in local climate policy, a systematic overview on climate mitigation and adaptation policy is still missing. This study aims to fill this gap by analysing 25 Dutch cities using indicators for the level of anchoring in policy, organisation and practical implementation as well as multi-level relations. Since Tilburg, Amsterdam, Den Haag and Rotterdam show a higher performance than other Dutch cities, these four cities are used as reference cities. The findings suggest that structural integration of climate mitigation and adaptation is limited in Dutch cities. The study points at three recent trends in local climate governance in the Netherlands: (i) decentralisation within municipal organisations, (ii) externalisation initiatives that place climate policy outside the municipal organisation and (iii) regionalisation with neighbouring municipalities and the provincial government.  相似文献   
296.
This article examines the continuities and changes in newspaper coverage of urban flood governance in Tabasco, southeastern Mexico, where highly destructive floods have made flood risks a socially sensitive and politically contested public issue. The analysis draws upon post-Foucauldian critical discourse analysis, paying special attention to different actors’ discursive strategies to further their agendas amid the shifting forms of environmental governance. We argue that in recent years, discourses that promote integrated flood governance, based on cultural adaptation and social resilience instead of technological control, have become prominent in the media presentation of flood governance. These discourses endorse neoliberal views of flood governance as an issue of public–private co-governance and civil self-responsibility while being reluctant to consider flood risk from the perspective of the uneven distribution of vulnerabilities or as an issue of human rights.  相似文献   
297.
湟水河小流域地下水脆弱性评价   总被引:1,自引:0,他引:1  
湟水河地处西北高原干旱地区,针对其流域地下水的特点,选取包气带介质、水位埋深、含水层介质、含水层厚度、净补给量和地形坡度共6个指标并运用三标度AHP法为各个指标赋予权重,构建了改进的DRASTIC模型。运用改进DRASTIC模型对湟水河的小流域范围的地下水脆弱性进行了评价。结果表明,湟水河沿岸的部分地区和西堡村附近地下水脆弱性高,地下水易受到污染。与传统DRASTIC模型相比,改进模型与实际情况更加吻合。  相似文献   
298.
本文通过对地方政府在农村环境治理中的职能定位,以及地方政府在农村环境治理中职能失效的原因分析,依据农村环境保护的相关立法和实践,重新梳理和配置地方政府的农村环境管理职能,从而探索农村环境治理的真正出路。  相似文献   
299.
Nature-based solutions (NBS) for mitigating climate change are gaining popularity. The number of NBS is increasing, but research gaps still exist at the governance level. The objectives of this paper are (i) to give an overview of the implemented NBS for flood risk management and mitigation in Germany, (ii) to identify governance models that are applied, and (iii) to explore the differences between these models. The results of a hierarchical clustering procedure and a qualitative analysis show that while no one-size-fits-all governance model exists, polycentricism is an important commonality between the projects. The study concludes by highlighting the need for further research on traditional governance model reconversion and paradigm changes. We expect the findings to identify what has worked in the past, as well as what is important for the implementation of NBS for flood risk management in future projects.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01412-x) contains supplementary material, which is available to authorized users.  相似文献   
300.
在分析2017年3月至2018年2月汉丰湖水体氮磷营养盐质量浓度季节性变化的基础上,利用氮磷化学计量摩尔比评估水体氮磷养分限制状态.结果表明:湖体TN、DN和NO3--N平均质量浓度分别为1.60、1.25和0.91 mg·L-1,三者季节变化过程相似,均呈现出冬季最高、夏季最低的特点.NO3--N对水体TN贡献较大,NH4+-N和NO2--N质量浓度维持在较低水平且变化平稳.TP、DP和PO43--P平均质量浓度分别为0.13、0.09和0.06 mg·L-1,TP和DP质量浓度变化相似,呈春夏季升高,秋冬季先降低再升高的趋势,而PO43--P质量浓度则波动降低.TN/TP范围在11.07~56.02之间,均值为29.23,TN/TP呈季节性波动变化,最高值出现在冬季,最低值出现在夏季.汉丰湖水体多数时间适宜藻类生长繁殖,少数时间处于N限制状态,极少数时间处于P限制状态.降雨径流、肥料使用、污水排放和水生生物活动等因素皆会影响TN/TP的季节变化,同时根据汉丰湖水质特征提出保护建议.  相似文献   
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