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971.
为探究人口规模、收入水平、消费倾向、节能政策和技术等因素对中国城镇生活能源消费的影响,基于拓展的STIRPAT模型并运用2000~2013年中国省际面板数据对各影响因素的效应进行评估。结果显示:城镇生活能源强度、城镇居民消费倾向、人均可支配收入、城镇化率、总人口、政策综合力度6个因素的增长率每变化1%,将会引起城镇生活能源消费量增长率0.9322%、0.8537%、(0.559 2+0.169 2 ln DI)%、0.599 8%、0.408 0%、-0.012 0%的变化,表明除节能政策外,其余5因素均正向促进城镇生活能耗增长。其中生活能源强度对城镇生活能耗影响最大,节能政策虽会抑制城镇生活能耗增长,但作用较为微弱。政府需继续加强节能政策综合实施力度,从而实现生活能源消费领域的节能减排。 相似文献
972.
21世纪充满着挑战,当世界上还有许多国家需要解决基本的生存问题之时,又要面对过去因单一的经济利益驱动而过度开发带来的环境问题、温室效应问题、资源危机问题等,人类要继续发展下去,就必须面对并尽可能解决这些问题。就解决温室效应问题而引出的低碳消费话题进行了一次调查问卷。调研获得的相关数据的结论,有助于南京市政府职能部门采取相应政策和措施,这样就可以引导南京市居民树立低碳消费理念,使南京市居民实施低碳消费行为。 相似文献
973.
The Sustainable Consumption and Production policy is a key objective in the renewed European Union (EU) Sustainable Development Strategy (SDS). EU countries implement the targets of Sustainable Consumption and Production policy at different a level. Nevertheless, SDS targets are concerned more with production than consumption side. In addition, analysis of the carbon footprint data, which was supplied by the Global Footprint Network, showed that in all EU countries consumption-based carbon footprint caught-up and exceeded the level of production-based carbon (except Denmark and Estonia) during 1993–2010 period. The significant absolute decoupling in terms of carbon footprint from production-based perspective was observed in Belgium, Denmark, Sweden, Slovakia, Poland, United Kingdom and Germany, meanwhile from consumption-based perspective only in Denmark, Estonia and Germany. Moreover in Spain, Portugal, Italy and Croatia the consumption-based carbon footprint grew faster than economy in general. Results imply that EU should put more focus on consumption side in terms of Sustainable Consumption and Production policy and measures taken. A commitment to reduce the environmental impact from consumption-based perspective should be more addressed covering values and lifestyles. 相似文献
974.
Integrated Coastal Zone Management (ICZM) aims to promote sustainable management of coastal zones based on ecosystem and holistic management approaches. In this context, policies have to consider the complex interactions that influence the fragile equilibrium of coastal ecosystems. Beaches represent both valuable and vulnerable natural resources because of the various ecosystem services they provide and their sensitivity to climate change and sea level rise.We present the first comprehensive digital record of all Black Sea beaches and provide a rapid assessment of their erosion risk under different scenarios of sea level rise. Through the digitisation of freely available remote-sensed images on the web, we provide broad information on the spatial characteristics and other attributes of all Black Sea beaches (e.g. photo-based visual estimation of the sediment type, presence of coastal defences, urban development). These data have been assembled and stored in full Spatial Data Infrastructure (SDI) – allowing spatial queries, visualisation and data sharing – and are therefore particularly interesting to feed/supply web-GIS portals (coastal atlases) for visualisation purpose, spatial queries or spatial indicators calculations.The resulting Black Sea beaches database contains 1228 beaches, with a total coastline length of 2042 km with an area of 224 km2. The majority of the Black Sea beaches have been found to have small widths (61% have maximum widths less than 50 m), whereas 47% of all beaches presented coastal defence schemes, suggesting an already serious beach erosion problem.The erosion risk of the Black Sea beaches was assessed through the comparison of their maximum widths with estimations of the sea level rise-induced retreat by an ensemble of six 1-D analytical and numerical morphodynamic models. Following more than 17,000 experiments using different combinations of wave conditions, beach sediment textures and slopes and 11 scenarios of sea level rise (up to 2 m), the means (best fits) of the lowest and highest projections by the model ensemble were estimated; these were then compared to the maximum widths of the Black Sea beaches. The analysis showed that sea level rise will have highly significant impacts on the Black Sea beaches, as for a 0.5 m sea level rise 56% of all beaches are projected to retreat by 50% of their maximum width. For a 0.82 m sea level rise (the high IPCC estimate for the period 2081–2100) about 41% are projected to retreat by their entire maximum width, whereas for 1 m sea level rise about 51% of all Black Sea beaches are projected to retreat by (drowned or shifted landward by) their entire maximum width, if the high mean of the model ensemble projections is used.Results substantiate the risk of beach erosion as a major environmental problem along the Black Sea coast, which therefore needs to be taken into account in any future coastal management plans, as a matter of urgency. As these scenarios consider only sea level rise, they are considered to be conservative. Although the present results cannot replace detailed studies, the database and projections may assist Black Sea coastal managers and policy makers to rapidly identify beaches with increased risk of erosion, valuate accordingly coastal assets and infrastructure, estimate beach capacity for touristic development purposes, and rapidly assess direct and indirect costs and benefits of beach protection options. They also provide the necessary inputs to advance discussions relevant to the Black Sea ICZM. 相似文献
975.
Per Mickwitz Mikael Hildén Jyri SeppäläMatti Melanen 《Journal of Cleaner Production》2011,19(16):1779-1787
This special issue of the Journal of Cleaner Production addresses system transformation by examining progress, stumbling blocks and opportunities for sustainable consumption and production in a specific country, Finland, set within a global context. The articles present and analyse top-down policy efforts, bottom-up efforts by municipalities, activities by companies and actions by consumers. They provide material for discussions on the shift from sustainability planning to enhancing system transformation, on the implications of globalisation for system boundaries, on the transformation of complex systems, on learning processes and on methods of assessing transitions. Without providing a singular solution, the articles show that issues of sustainability should be explored in different ways within different contexts, and experimented with. There is a continuous need for transformations and reflexive learning, since conditions are likely to become very different, not least due to climate change. The notion of change and transformation will be high on the agenda of the Rio+20 conference, as will similar efforts to promote large-scale transformations of consumption and production. 相似文献
976.
977.
选取决策树作为支持向量机多类分类方法,选择径向基核函数建立了生态环境质量决策树支持向量机评价模型,基于遗传算法实现了惩罚因子、核函数参数的自适应优选,并运用建立的模型对我国主要省市生态环境质量进行了评价。研究结果表明,该方法可以较好地实现生态环境质量评价。 相似文献
978.
The 11 th Five Year Plan has divided national functional zones in the basic unit of county-level administrative region. Af- ter implementation of national Major Function-oriented Zones (MFOZ) at prefec... 相似文献
979.
基于信息熵的城市居民家庭能源消费结构演变分析——以无锡市为例 总被引:28,自引:1,他引:27
受能源赋存状况及经济发展水平影响,不同地区之间的能源消费结构往往存在很大差别,对其结构演变很难用一个具体的指标来衡量。论文通过信息熵的引入,试图来解决这个问题,并最终取得了满意的效果和结论。对无锡市1990~2002年间城市居民家庭能源消费结构的熵值演变特征进行动态分析后发现,1994年前后,无锡市城市居民家庭能源消费结构信息熵的变化呈现出截然相反的特征,并且与城镇居民实际可支配收入及人均能源消费总量变化高度相关。在深入分析其演化特征和原因的基础上,对无锡市城市居民能源消费结构的演化方向作出了展望。 相似文献
980.