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291.
历史文化遗产作为城市的重要组成部分,与城市的文化、经济、生活具有高度的关联性,其科学合理的保护利用已成为学术界和政府共同关注的热点问题。从城市产业结构调整、用地性质置换等方面入手,以四川省三台县为例进行了实证研究,试图提出一种以经济发展为引导的历史文化遗产保护模式,使其与城市经济协调、可持续地发展。  相似文献   
292.
基于新制度经济学视角的“河长制”评析   总被引:8,自引:0,他引:8  
我国频发的水危机既是水环境作为居住地、供应站功能而引发的生态破坏问题,也是作为废物库功能而引发的环境污染问题.河长制是地方政府为了重新恢复环境三大功能协调运行而发明的一项有效的实用制度.河长制因其简单易行,很快在全国形成扩散效应.河长制是源于地方政府的制度创新,本文运用新制度经济学分析了河长制的优缺点:优点是职责归属明确,权责清晰;是合理的路径依赖基础上的制度创薪;铁腕治污提高治污效率;创新扩散机制值得提倡.河长制本身存在制度缺陷:无法根除委托-代理问题;缺乏透明的监督机制;容易出现利益合谋;忽视了社会力量;行政问责很难落实.河长制综合考虑了地方权力结构与环境现实,充分利用行政长官手中的权力带动地方政府职能转变,推动了具有中国本土特色环境制度变迁的步伐.但河长制具有应急的过渡性,应在发展中扬长避短,不断完善,应通过它形成全社会参与环境管理的机制,建立可持续发展的环境治理制度.  相似文献   
293.
针对特种设备数量和种类不断增多与安全监管力量不足问题,首先阐述特种设备安全监管内涵,分析其涉及的委托代理关系;然后基于委托代理理论构建特种设备安全监管委托代理数学模型,并利用激励相容约束条件讨论监管力度、安全投入、公众信任度等因素对特种设备安全监管效果的影响及内在机制;最后提出进一步提高特种设备安全水平的改进策略.结果...  相似文献   
294.
Ecological systems often operate on time scales significantly longer or shorter than the time scales typical of human decision making, which causes substantial difficulty for conservation and management in socioecological systems. For example, invasive species may move faster than humans can diagnose problems and initiate solutions, and climate systems may exhibit long‐term inertia and short‐term fluctuations that obscure learning about the efficacy of management efforts in many ecological systems. We adopted a management‐decision framework that distinguishes decision makers within public institutions from individual actors within the social system, calls attention to the ways socioecological systems respond to decision makers’ actions, and notes institutional learning that accrues from observing these responses. We used this framework, along with insights from bedeviling conservation problems, to create a typology that identifies problematic time‐scale mismatches occurring between individual decision makers in public institutions and between individual actors in the social or ecological system. We also considered solutions that involve modifying human perception and behavior at the individual level as a means of resolving these problematic mismatches. The potential solutions are derived from the behavioral economics and psychology literature on temporal challenges in decision making, such as the human tendency to discount future outcomes at irrationally high rates. These solutions range from framing environmental decisions to enhance the salience of long‐term consequences, to using structured decision processes that make time scales of actions and consequences more explicit, to structural solutions aimed at altering the consequences of short‐sighted behavior to make it less appealing. Additional application of these tools and long‐term evaluation measures that assess not just behavioral changes but also associated changes in ecological systems are needed.  相似文献   
295.
全球能源经济可计算一般均衡(Computable General Equilibrium Model,CGE)模型是研究低碳政策对能源经济系统影响的主要工具,在国际低碳经济研究领域具有重要作用。全球能源经济CGE模型发展起始于20世纪70年代,经过数十年的拓展已经形成了一批发展成熟且应用广泛的模型平台。我国能源经济CGE模型研究开始于20世纪90年代,研究领域主要聚焦在中国本土与国内区域,而在全球尺度上的模型研究尚处于起步阶段。伴随我国在全球气候治理当中的重要性凸显,中国能源环境问题的研究需要具有国际视野。本文对当前全球能源经济CGE模型的研究现状进行分析,对全球CGE模型的主要作用与特点做出评价,并对典型模型进行比较,在介绍了模型优缺点的基础上对全球能源经济CGE模型的发展趋势与关键问题进行讨论,并对中国未来发展全球模型给出具体建议。全球能源经济CGE模型政策评估的主要优点是评估基于坚实的理论基础,可以根据相关理论判断模型结果是否合理并对政策的作用机制与影响结果做出基于经济规律的解释;以及能源与经济系统整体协调一致的相互作用机制。能源经济CGE模型主要争议性问题包括结果依赖大量参数且参数取值不稳健,以及模型假设过于理想且技术表达抽象。当前能源经济CGE模型研究的关键问题与主要趋向包括:关键参数的实证研究与准确校核、经济系统异质化与细节化描述、技术细节表述与内生化变革以及非理想与不均衡市场条件建模。建议中国开发全球模型应充分借鉴全球先进模型开发的基础与经验,在当前全球模型主流框架下重点研究发展中国家在非理想与不均衡市场环境下经济行为表述的改进,同时注重模型基础数据的整理与重要参数的校核。  相似文献   
296.
Hilkert Colby, Elizabeth J., Thomas M. Young, Peter G. Green, and Jeannie L. Darby, 2010. Costs of Arsenic Treatment for Potable Water in California and Comparison to U.S. Environmental Protection Agency Affordability Metrics. Journal of the American Water Resources Association (JAWRA) 46(6):1238–1254. DOI: 10.1111/j.1752-1688.2010.00488.x Abstract: The United States (U.S.) federal standard for arsenic in potable water systems is only the second water quality standard in which the U.S. Environmental Protection Agency (USEPA) administrator used “discretionary authority to establish a less stringent standard” based on the results of cost-benefit analyses. Based on the findings that a “standard of 3 μg/l would be feasible but not justified,” the revised maximum contaminant level (MCL) lowered the allowable arsenic concentration from 50 to 10 μg/l in 2002. In 2009, approximately 145 systems in California were out of compliance. The objectives were to gather performance and cost data from arsenic treatment systems in California to compare with data from the USEPA demonstration sites as well as with the USEPA affordability metrics for drinking water. The median cost of compliance with the revised arsenic MCL for the 36 surveyed systems was $1.95/1,000 gallons (2008 dollars), which is 69% of the average cost of delivered tap water in the U.S. in 2008 ($2.81/1,000 gallons). Additionally, 22% of the surveyed systems in California paid more than the maximum predicted cost of compliance with the revised arsenic MCL ($5.05/1,000 gallons). The largest variation in cost was seen in the systems that treated <500 gpm. For the systems utilizing adsorption, systems obtained between 20 and 80% of the expected bed volumes prior to breakthrough, indicating the need for better prediction of performance.  相似文献   
297.
Texas water resources, already taxed by drought and population growth, could be further stressed by possible listings of endangered aquatic species. This study estimated potential economic impacts of environmental flows (EFs) for five freshwater unionid mussels in three Central Texas basins (Brazos, Colorado, and Guadalupe‐San Antonio Rivers) that encompass 36% of Texas (~246,000 km2). A water availability model projected reductions in water supply to power, commercial and industrial, municipal, and agriculture sectors in response to possible EFs for mussels. Single‐year economic impacts were calculated using publicly available data with and without water transfers. Benefits of EFs should also be assessed, should critical habitat be proposed. Potential economic losses were highest during droughts, but were nominal (<$1 M) in wetter years — even with high EFs. Reduced supplies to San Antonio area power plants caused worst‐case impacts of a single‐year shutdown up to $107 million (M) during drought with high EFs. For other sectors in the study area, water transfers reduced worst‐case losses from $80 to $11 M per year. Implementing innovative water management strategies such as water markets, conjunctive use of surface water and groundwater, aquifer storage and recovery could mitigate economic impacts if mussels — or other widely distributed aquatic species — were listed. However, approaches for defining EFs and strategies for mitigating economic impacts of EFs are needed.  相似文献   
298.
This article assesses the sustainability potential of the urban water systems in Europe (UWSE) following their modernisation. A decade after implementation and close to the first deadlines, modernisation efforts seem to have not been (totally) successful. This article examines the ability of governance to achieve sustainability and poses the question of how modernisation develops a particular “terrain” more or less favourable to sustainability. We use the Institutional resource regimes framework which has been dedicated to determining the potential for sustainability of natural resources regulation. Conclusions show that the modernisation of UWSEs offers a path for progress which though necessary is insufficient due to a lack of coherence between policy design and the regulatory system. Globally, the development of regulation goes hand in hand with increasing inconsistencies that reduce the efficiency of the reform.  相似文献   
299.
Tax-aversion reduces the likelihood that price rationing can be a politically viable tool for environmental protection. We examine the case of the classic Pigouvian tax to control a negative externality, and consider how recycling the revenues, labeling of the tax and information about its purpose affects the support for taxation. We test the support for taxation within a single-price market experiment, in which purchases by some buyers impose external costs on others. Observing behavior consistent with tax-aversion, we also find that recycling the revenues to more narrowly targeted groups seems to increase support for taxation. In the absence of narrow revenue recycling, labeling a Pigouvian instrument as a ‘tax’ may significantly lower the likelihood of voter support.  相似文献   
300.
Huang, Biao, Christian Langpap, and Richard M. Adams, 2011. Using Instream Water Temperature Forecasts for Fisheries Management: An Application in the Pacific Northwest. Journal of the American Water Resources Association (JAWRA) 47(4):861‐876. DOI: 10.1111/j.1752‐1688.2011.00562.x Abstract: Water temperature is an important factor affecting aquatic life within the stream environment. Cold water species, such as salmonids, are particularly susceptible to elevated water temperatures. This paper examines the potential usefulness of short‐term (7 to 10 days) water temperature forecasts for salmonid management. Forecasts may be valuable if they allow the water resource manager to make better water allocation decisions. This study considers two applications: water releases from Lewiston Dam for management of adult Chinook salmon (Oncorhynchus tshawytscha) in the Klamath River and leasing water from agriculture for management of steelhead trout (Oncorhynchus mykiss) in the John Day River. We incorporate biophysical models and water temperature distribution data into a Bayesian framework to simulate changes in fish populations and the corresponding opportunity cost of water under different levels of temperature forecast reliability. Simulation results indicate that use of the forecasts results in increased fish production and that marginal costs decline as forecast reliability increases, suggesting that provision and use of such stream temperature forecasts would have potential value to society.  相似文献   
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