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261.
刘颖昊  刘涛  郭水华 《环境工程》2012,(Z2):437-439
钢铁产品性能的提高往往会增加其制造环节的环境负荷,但是在很多领域的使用过程中,高性能钢材相对于普通钢材,更有利于环境。因此评估钢铁产品改进的环境效益需要一个系统化的科学方法———生命周期评价(LCA)。从钢铁产品全生命周期视角,讨论了钢铁产品性能提升与环境影响的关系,阐述了如何利用LCA方法评估钢铁产品全生命周期环境绩效,并列举了宝钢利用LCA方法评估钢铁产品性能改进环境效益的两个案例:某变压器采用性能更高的B30P110取向硅钢片取代原B30G130取向硅钢片,其生命周期碳减排15.1%;宝钢钢制二片罐用镀锡钢板从0.28mm经过6次减薄到0.225mm,使钢罐生命周期碳排放降低14.5%。  相似文献   
262.
Abstract: Ecosystem services are being protected and restored worldwide through payments for ecosystem services in which participants are paid to alter their land‐management approaches to benefit the environment. The efficiency of such investments depends on the design of the payment scheme. Land features have been used to measure the environmental benefits of and amount of payment for land enrollment in payment for ecosystem services schemes. Household characteristics of program participants, however, may also be important in the targeting of land for enrollment. We used the characteristics of households participating in China's Grain‐to‐Green program, and features of enrolled land to examine the targeting of land enrollment in that program in Wolong Nature Reserve. We compared levels of environmental benefits that can be obtained through cost‐effective targeting of land enrollment for different types of benefits under different payment schemes. The efficiency of investments in a discriminative payment scheme (payments differ according to opportunity costs, i.e., landholders’ costs of forgoing alternative uses of land) was substantially higher than in a flat payment scheme (same price paid to all participants). Both optimal targeting and suboptimal targeting of land enrollment for environmental benefits achieved substantially more environmental benefits than random selection of land for enrollment. Our results suggest that cost‐effective targeting of land through the use of discriminative conservation payments can substantially improve the efficiency of investments in the Grain‐to‐Green program and other payment for ecosystem services programs.  相似文献   
263.
Agricultural conservation easements (ACEs) involve the significant expenditure of public funds through either tax benefits and/or direct public expenditures. The selection of agricultural parcels for conservation should, therefore, maximise net public benefits to the extent possible within financial constraints and the need for agricultural viability to maintain working landscapes. Some programmes select agricultural parcels for conservation easements based only on agricultural viability and/or land cost, however, without explicit consideration of the many other public benefits often associated with ACEs. This paper illustrates application of a method for increasing the public benefits of agricultural conservation easements through a case study in the northern San Joaquin Valley of California. The method is a strategic planning process that incorporates both a GIS-based quantitative assessment and a more qualitative assessment. Such an approach is a supplement to – rather than a substitute for – the more science-based Landscape Evaluation and Site Evaluation (LESA) approach developed by the US Soil Conservation Service (SCS) and cost-minimisation approaches that emphasise economic considerations. However, we show that public land use planning and regulatory policies are essential for agricultural conservation. Acquisition strategies in isolation will not be successful without complementary public regulatory policies.  相似文献   
264.
从环境效益、技术可行性、经济效益及对生产的影响等方面进行清洁生产审核效果分析和评价。介绍了风城油田作业区自实施清洁生产以来,审核工作开展情况,物料与能耗分析;筛选出无费方案2个、低费方案6个、中费方案4个、高费方案2个,实施率分别为100%、100%、50%和100%。结论如下:节约电能1209.19万kW·h/a,节约天然气2739.25×10~4m~3/a,减少CO_2排放27682.84 t/a,减少NO_2排放645.22 t/a,减少SO_2排放17.35 t/a,减少烟尘排放396.90 t/a,减少固体废物排放0.12t/a,清洁生产方案将产生经济效益达4263.32万元/a。  相似文献   
265.
本文对生态工业园的概念及其建设的重要作用作了介绍。以大连经济技术开发区生态工业园的建设为例,探讨了生态工业园的建设方法,并分析了生态工业园建设所带来的经济效益,从而阐明了生态工业园建设对于发展循环经济的重要战略意义。生态工业园建设是我国发展循环经济、实现经济社会可持续发展的战略选择。生态工业园建设应围绕主导产业构建生态工业产业链,实现区内资源循环利用并运用产业生态管理。  相似文献   
266.
Resource purchasing funds have become a major tool for environmental protection and resource conservation. These funds use various strategies to target resources for conservation, the choice of which may lead to striking differences in environmental performance. This paper develops an analytical framework to analyze the impact of alternative targeting strategies on different interest groups, including consumers, producers, labor, and environmentalists. We show that ignoring the output price effect of purchasing funds reduces environmental gain and in some cases may make a purchasing fund counterproductive, and we argue that the optimal design of targeting criteria must consider the price feedback effect.  相似文献   
267.
绿色经济新理念及中国开展绿色经济研究的思考   总被引:2,自引:0,他引:2  
联合国里约20周年世界峰会的重要内容之一是倡导绿色经济。绿色经济的概念最早在1989年由英国环境经济学家Pearce提出,但现在的绿色经济却具有全新的意义。本文基于参加联合国有关绿色新政和绿色经济的政策咨询和研究报告,论述了绿色经济的基本背景、三重效益、研究模型以及绿色经济与生活质量的关系,对如何开展中国绿色经济研究进行探讨。首先,文章认为在深入探讨绿色经济前,需要了解当前发展绿色经济的基本背景,明确为什么要发展绿色经济、什么才是我们所需要的绿色经济,以及怎样促进绿色经济发展三个基本问题。其二,绿色经济与褐色经济的情景模拟表明,绿色经济发展模式具有更好的三重底线效益。联合国的T-21模型对过去40年(1970-2010)及未来40年(2010-2050)进行了绿色情景与褐色情景两种模拟,认为在自然资本的环境收益方面,绿色经济发展情景下自然资本的退化得到了基本遏制,而褐色经济发展情景下自然资本的退化会进一步增强;在物质资本的经济收益方面,绿色经济发展情景下,2020年以前经济增长率(2.5%)会低于褐色经济(3%),但从长期平均增长率看绿色经济发展模式(2.5%)可以带来比褐色经济发展模式(2%)更好的经济增长;在人力资本的社会效益方面,在2030年以前绿色经济发展情景下就业机会有小幅减少,但长期来看,绿色经济能够创造与褐色经济同样多的就业机会,甚至可以有小幅的增加(0.6%)。其三,绿色经济研究模型表明,绿色经济投资于自然资本可以实现所需要的经济社会发展与自然资本消耗的脱钩。绿色经济假说是:将资金投资于提高资源能源效率与扩大自然资本两个方面,是否能够导致更好的经济社会发展。基于该理论假设,联合国等国际组织将自然资本引入生产函数,建立了Threshold-21模型,证明绿色经济即投资于自然资本可以实现所需要的经济社会发展与自然资本消耗的脱钩。其四,绿色经济发展模式不仅有利于经济增长,同时能够增加生活质量。绿色经济假说,强调了绿色投资对生活质量有正的影响。通过生态绩效模型、结构方程模型以及典型案例研究等三种方法进行分析,研究表明:减少自然资本消耗可以减少生态环境的治理成本和维护成本、维持与增加自然资本对人类的功能;可以提高自然资本的生产效率,用较少的自然资本投入达到社会稳定所需要的人造资本;可以提高人造资本的服务效率,用一定的物质存量为更多的人服务。其五,开展深化中国绿色经济理论与绿色发展模式的系统研究。联合国等国际组织倡导的绿色经济可以给我们发展中国的绿色经济带来新的启示,笔者认为对中国绿色经济理论与绿色发展模式开展深入和系统的研究,应该包括理论内涵、实证分析、发展情景、行动领域、政策体系等五个依次递进、前后照应的研究模块。  相似文献   
268.
Mangi SC  Rodwell LD  Hattam C 《Ambio》2011,40(5):457-468
Shortly after the implementation of a marine protected area (MPA) in Lyme Bay in 2008, inside which scallop dredging and bottom trawling is prohibited, a socio-economic impact assessment was initiated. This article presents the initial findings from this study. The aim was to understand the costs and benefits to fishermen and fish merchants of establishing the MPA. These were assessed using a combination of primary and secondary data. The results indicate that the impacts of the closure differ according to the gear type and the fishing location used by the fishermen. Static gear fishermen who fish inside the closed area have seen changes in terms of increased fishing effort, mostly because they have been able to increase the number of crab and whelk pots they deploy. The effects of the closure on static gear fishermen who fish outside the closed area has been reported in terms of increased conflicts with towed gear fishermen who now fish regularly in their traditional grounds. Fishermen using towed gear on the other hand have been impacted through displacement effects as they have been forced to look for other fishing grounds outside the closed area. Most fish merchants and processors initially claimed that they were heavily impacted by the closure but when they were interviewed 1 year after the closure they suggested a more stable picture. Preliminary analyses of landings data indicate that the introduction of the MPA has so far had minimal impacts on the average incomes and financial profits of fishermen and fish merchants. This conclusion, however, reflects a short-term view as the impacts of the closure of Lyme Bay are likely to be felt for a long time to come.  相似文献   
269.
Phosphorus recovery from wastewater has become a necessity for sustainable development because phosphorus is a non-renewable essential resource, and its discharge into the environment causes serious negative impacts. There are no economic incentives for the implementation of phosphorus recovery technologies because the selling price of rock phosphate is lower than phosphorus recovered from sewage. The methodologies used to determine the feasibility of such projects are usually focused on internal costs without considering environmental externalities. This article shows a methodology to assess the economic feasibility of wastewater phosphorus recovery projects that takes into account internal and external impacts. The shadow price of phosphorus is estimated using the directional distance function to measure the environmental benefits obtained by preventing the discharge of phosphorus into the environment. The economic feasibility analysis taking into account the environmental benefits shows that the phosphorus recovery is viable not only from sustainable development but also from an economic point of view.  相似文献   
270.
新疆和田地区人工柽柳生态修复工程生态效益监测初探   总被引:1,自引:0,他引:1  
通过在和田地区生态修复项目设立样方,监测生态修复项目实施后所取得的生态效益.结果表明,生态修复项目实施后,能够降低项目区的风速,提高温度和相对湿度;提高植被盖度;改善土壤理化性质,但由于项目实施时间较短,作用不是非常显著;生态修复项目的实施取得了较好的生态效益.  相似文献   
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