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161.
ABSTRACT: The problem of nonmatching irrigation and solar power production seasons creates the problem of what to do with the surplus power. The economic law of opportunity cost dictates that substitution for currently commercially purchased power is the best use for this power. This law also allows for new power using enterprises that satisfy specific criteria to be used on the farm before sale of the residual to a local public utility can be considered. Economic and Financial Evaluation of the solar powered irrigation system show that the price of commercially purchased power must reach 9.5 cents per Kwh before the system is feasible under the ideal assumption of complete use of the residual power to substitute for commercially purchased power.  相似文献   
162.
ABSTRACT. As a result of several investigations conducted in the Department of Civil Engineering through the Water Resources Research Center at The University of Tennessee, dating from 1966 to the present, a rather comprehensive surveillance of water quality conditions has been maintained in Forth Loudoun Reservoir on the Tennessee River near Knowville, Tennessee. During the period covered by these investigations, the Knoxville Third Creek Sewage Treatment Plant was upgraded from a primary plant to a secondary (activated sludge) treatment plant. Comparison of the collected data is being undertaken herein to elucidate the impact of these modifications upon water quality conditions in the reservoir. Consideration is given to the improvements of water quality as related to the expenditure for modification of the treatment facilities. In addition, comment is directed toward the public health significance of the water quality conditions determined.  相似文献   
163.
The Sierra Club, which has long fought selected water resource projects that it believes would be environmentally damaging, has come to the conclusion in recent years that much more basic reforms are required in water resources development activities if the demands for environmental quality now evidenced by the American people are to be satisfied. These reforms should not be limited to those that would have a direct effect on the environmental aspects of proposed projects, but also many others long advocated by the economics profession that would have favorable indirect effects. Among the urgent reforms with indirect effects are those involving revision of the procedures used in evaluating proposed projects. These procedures should be revised so that future evaluations will much more accurately reflect the economic and environmental merits of proposed projects. Basic reforms of tax policies are also needed that will eliminate most of the private profit available to those who can persuade the government to increase the value of their land through the construction of water projects. Finally, some additional actions can be taken that will have a direct impact on lessening the adverse environmental impact of water projects beyond the provisions of the National Environmental Policy Act of 1969.  相似文献   
164.
对产生环境污染人的行为的经济学分析   总被引:2,自引:0,他引:2  
本文运用现代经济学原理 ,分析了产生环境污染的人们的行为 ,从而了解人们产生环境污染的行为的深层次原因  相似文献   
165.
Transport users do not currently pay all costs associated with their transport activities and in particular do not pay the costs they impose on the environment. Case studies on Dublin, Amsterdam, Brussels and London have been conducted to evaluate how best to meet the requirement of the European Commission in its fair and efficient pricing aims in the transport sector, i.e. where transport users are made to pay all costs they impose. The paper presents the results of Do Nothing (DN) and Do Something (DS) scenarios for 2005 where in the latter case each transport user pays for all costs they impose including pollution, noise, accidents etc. The Dublin results, from an economics model used in the study, are examined in detail; the findings are compared with those of parallel studies conducted in the other cities to demonstrate the international relevance of this work. The comparison between the DN and DS scenarios indicates that taxes on all transport modes should be increased substantially, particularly in the morning and evening peak periods. As a result of the price increases, travel demand is reduced. A practical example where transport users could be made to pay for all their costs is road use pricing, i.e. charging individuals for the use of road space. The taxation levels suggested in the DS scenario have been used in a road use pricing trial in Dublin, the results of which were published in O'Mahony, Geraghty and Humphreys (Transportation 27, 269-283, 2000), to see if the reductions in the travel requirements of individuals proposed by the economics model are in fact true. The principles of the work presented in this paper are not only relevant to environmental impact management in the transport sector but can also be applied to other sectors.  相似文献   
166.
ABSTRACT: Enforceable standards play a crucial role in the design and implementation of most water quality policies. The impacts of these standards on farm income and nonpoint source (NPS) pollution can provide valuable information to develop economic policies that can improve water quality with minimal loss in income and minimal risk. This study uses an integration of nonlinear programming and a simulation model to assess the impacts of enforceable standards at technology and farm boundary levels. The results indicate that the type of pollutant regulated, enforcement type, and the level of standard had a significant impact on farm income and water quality. Choice of farm boundary standards over technology standards is dependent on the impact of the policy on other NPS pollutants, in addition to the reduction of nitrate and phosphorus pollutants. Enforcing farm boundary standards on nitrates had desirable effects on subsurface and percolate nitrogen and variance in income. Technology standards were uncertain in their effects because of the restriction on the choice of technologies available to farmers. A comparative policy analysis considering incentives, multiple impacts, transaction costs of implementation, and regional consideration is important to an effective policy design.  相似文献   
167.
旅行成本法在我国应用中存在的几个问题   总被引:10,自引:1,他引:9  
我国旅行成本法案例研究多数未分清旅行成本与旅游目的地本身价格的关系,推导的游憩需求曲线是旅行成本-旅游人次模型,而不是旅游目的地本身的价格-旅游人次需求曲线。文章具体说明了区域旅行成本法的基本原理及操作方法,并用乔光华文章数据重新对达里诺尔国家级自然保护区游憩价值进行计算,对旅行成本的构成等问题进行了讨论,得出其消费者剩余为0.9221×108元a/,比原研究中的0.0937×108元a/高出近10倍。认为乔光华等的研究在推断游憩需求曲线时存在方法上的问题,直接将旅行成本和时间价值作为游憩价值不符合旅行成本法的基本原理和公共物品无(或低)市场价格的经济理论。还对调整后的旅行成本数据进行了计算,得到保护区游憩价值为1.3581×108元a/。  相似文献   
168.
基于生态足迹方法的中国生态可持续性分析   总被引:2,自引:1,他引:1  
基于生态足迹和EMD方法,分析了中国1961~2005年生态可持续性的周期性变化,并建立具有周期性波动的非线性动力学模型,预测未来10年中国人均生态足迹和生物承载力的发展趋势。结果发现:44年来,中国人均生态足迹具有明显的4.3年、14.3年和17年3个波动周期,人均生物承载力具有明显的3.5年、8.8年、17.7年和44年4个波动周期;若未来10年中国人均生态足迹和生物承载力均延续过去44年的变化趋势,则2015年人均生态足迹、生物承载力、生态赤字将分别为1.366ghm2、1.108ghm2和0.258ghm2,人均生态足迹和生态赤字较2005年分别下降了0.27ghm2、0.441ghm2,而人均生物承载力增加了0.171ghm2。在保持经济、技术和人民生活水平稳步提高的同时,这种程度的生态超载有可能通过贸易引进生物承载力,通过技术进步、提高管理水平等增加生物承载力得到缓解。  相似文献   
169.
This article proposed the concept of"climate capacity"as a way of measuring human’s adaptiveness to climate change.This article also focused on the related concepts like ecological carrying capacity,water resources carrying capacity,land carrying capacity as well as population carrying capacity.The concept of climate capacity was articulated against a background of global climate and environmental change.Essentially,China’s efforts to adapt to climate change was a matter of improving climate capacity,which is the ecosystem as well as the frequency,the intensity and the scale of human’s social activities that the climatic resources of a particular geographic area were supposed to support.The climate capacity has two components.One is the natural climate capacity,which includes temperature,sunlight,precipitation,extreme climatic events,etc.The other is the derived climate capacity,which includes water resources,land resources,ecological systems,climatic risks,etc.The climate capacity can be developed or be transferred between regions by taking engineering,technology or regime-based adaptive measures.However,these adaptive measures must be implemented under the principle of economic rationalism,ecological integrity,climate protection,and social justice.It is expected that by combining the climate capacity and its threshold value with the assessment of climate change risks,we are able to predict the optimal population carrying capacity and the scale of socioeconomic development,and furthermore,provide policy support for the socioeconomic development strategy and adaptive planning.In the regions with high climate capacity,there is a symbiotic relationship between adaptation and socioeconomic development.But,in the regions with limited climate capacity,irrational development may further damage the environment.Taking the Yangtze River delta,a region with high climate capacity,and a region of Ningxia,a region with limited climate capacity,as illustrative examples,the authors of this article analyzed the policy implications of climate capacity and further made suggestions on the problems of capacitylimited adaptation and development-driven adaptation.This article argued that the concept of climate capacity can not only be used as an analytical instrument of climate change economics,but also it can provide research support for planning regional adaptation and development with climate change impact and risk assessments.  相似文献   
170.
如何揭示利益相关者生态补偿的真实意愿不但是生态系统服务支付研究的难点问题,也是政府及管理部门制定生态补偿政策的关键问题。为此,论文通过对辽河流域中游地区的7个主要城市进行实地调研,采用条件价值评估法,利用同一受访者同时测量其支付意愿值(WTP)和受偿意愿值(WTA)的技术手段来检验其真实补偿意愿,研究结果显示,受访地区居民保护流域生态环境和水资源的WTP为59.39元/(人·a),WTA为248.56/(人·a);同时,针对同一受访者给出的WTP与WTA之间的较大差异性利用回归分析方法,得出其呈现不对称性的主要原因是受访者的收入水平和年龄。最后,在对研究结果进行差异性分析的基础上,提出了辽河流域生态补偿意愿差异性的研究结论和政策建议。  相似文献   
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