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111.
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Land application of broiler litter is a common disposal method due to its value as a fertiliser substitute, but presents potential environmental problems because of nutrient runoff. Composting has been suggested as an alternative due to the formation of more stable organic components. The land application of fresh and composted broiler litter are compared as alternative disposal methods. The costs of land application of broiler litter are dominated by spreading because of low nutrient densities relative to commercial fertilisers. Composting broiler litter before land application appears to be substantially less economically attractive than land application of fresh broiler litter because of high costs of production and higher spreading costs due to even lower nutrient density. However, when environmental constraints are placed on the phosphorus concentration from hayfield runoff, composting becomes a more attractive alternative. Composting becomes more viable as the land base for application becomes smaller relative to broiler production; as alternative disposal costs for litter become higher; and as environmental constraints become stricter. 相似文献
113.
Lisa A. McDonald Grace M. Johns 《Journal of the American Water Resources Association》1999,35(3):579-592
ABSTRACT: Successful watershed management requires consideration of multiple objectives and the efficient use of scarce public and private resources. One way to address these multi-faceted issues is through Social Benefit-Cost Accounting (SBCA). SBCA is a systematic method of addressing complex social and economic issues relevant to proposed watershed management projects. Benefits of using this technique include: benefits and costs of watershed projects are better understood; politically sensitive issues tend to be put into perspective; and stakeholders' interests are placed on a level playing field. An example from Bogota, Colombia demonstrates how SBCA can be used to value the benefits and costs of a proposed project. By addressing the benefits and costs to all stakeholders, the design of watershed management programs can be improved to achieve goals in a cost-effective manner. 相似文献
114.
Upton Hatch Shrikant Jagtap Jim Jones Marshall Lamb 《Journal of the American Water Resources Association》1999,35(6):1551-1561
ABSTRACT: Climate change has the potential to have dramatic effects on the agricultural sector nationally and internationally as documented in many research papers. This paper reports on research that was focused on a specific crop growing area to demonstrate how farm managers might respond to climate-induced yield changes and the implications of these responses for agricultural water use. The Hadley model was used to generate climate scenarios for important agricultural areas of Georgia in 2030 and 2090. Linked crop response models indicated generally positive yield changes, as increased temperatures were associated with increased precipitation and CO2. Using a farm management model, differences in climate-induced yield impacts among crops led to changes in crop mix and associated water use; non-irrigated cropland received greater benefit since irrigated land was already receiving adequate moisture. Model results suggest that farm managers will increase cropping intensity by decreasing fallowing and increasing double cropping; corn acreage decreased dramatically, peanuts decreased moderately and cotton and winter wheat increased. Water use on currently irrigated cropland fell. The potential for increased water use through conversion of agriculturally important, but currently non-irrigated, growing areas is substantial. 相似文献
115.
Jonathan I. Eisen‐Hecht Randall A. Kramer 《Journal of the American Water Resources Association》2002,38(2):453-465
ABSTRACT: The primary objective of this study was to perform a cost‐benefit analysis of maintaining the current level of water quality in the Catawba River basin. Economic benefits were estimated using a stated preference survey method designed to value respondents' willingness to pay for a management plan to protect water quality in the Catawba basin over time. From the surveys conducted with 1,085 area residents, we calculated an annual mean willingness to pay of $139 for the management plan, or more than $75.4 million for all taxpayers in the area. Over the five‐year time horizon in which respondents were asked to pay for the management plan, this resulted in a total economic benefit of $340.1 million. The Watershed Analysis Risk Management Framework model was used to estimate the amount of management activities needed to protect the current level of water quality in the basin over time. Based on the model results, the total cost of the management plan was calculated to be $244.8 million over a ten‐year period. The resulting cost‐benefit analysis indicated that the potential benefits of this management plan would outweigh the costs by more than $95 million. 相似文献
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基于经济学视角的职业健康规制问题研究 总被引:1,自引:1,他引:0
张秋秋 《中国安全科学学报》2010,20(5)
用经济学分析工具对现有的职业健康规制进行探讨,研究规制机构、企业和劳动者三方行为主体的博弈,通过分析存在的问题,提出解决职业健康规制的对策。在理顺职业健康规制体制,健全机构的同时不断完善法规体系。同时,加强对劳动者职业健康的保障,完善第三方介入机制,并且加大对违规企业的处罚力度,提高对劳动者的赔偿。不断强化企业作为职业健康责任主体的意识,推进职业危害防治技术创新,培养"以人为本"的职业健康安全文化观念。 相似文献
118.
环境经济学在中国的发展 总被引:11,自引:0,他引:11
夏光 《中国人口.资源与环境》1999,9(1):22-26
本文讨论了环境经济学在中国的发展过程,并对新时期环境经济学面临的理论和现实问题进行了展望。在新的时期,环境经济学应更加注重以环境问题表现的社会利益结构和利益均衡的实证分析,并对满足可持续发展要求的宏观经济政策变革和微观环境管理提供理论支持。 相似文献
119.
铅酸蓄电池由于含有大量的重金属成分,属于危险废物,如果不进行妥善处理,将对环境和人体健康产生严重威胁,但铅酸蓄电池又具有较高的回收利用价值,因此对废旧铅酸蓄电池的合理有效回收利用有着极大的必要性。比较了国内外铅酸蓄电池回收利用体制,提出我国废旧铅酸蓄电池回收行业的发展建议,为此类二次资源的合理有效利用提供借鉴。 相似文献
120.
工伤保险行业差别费率确定方法探讨 总被引:2,自引:0,他引:2
制定合理的行业差别费率对于工伤保险基金的稳定、促进企业改善安全生产状况具有积极作用.我国工伤保险制度处于起步阶段,有些地区对行业差别费率厘定进行了探索,但费率与风险的关联性不强,影响了低风险企业参加工伤保险统筹的积极性.本文针对工伤统计数据缺乏的现状,分析了现阶段工伤保险行业差别费率确定方法的研究现状,重点讨论了确定行业风险等级的3种方法,即聚类分析法、风险系数测评和模糊风险评估法的应用过程以及优缺点;另外,强调了在确定行业风险指数时,应注意根据不同事故类别的严重度来确定各风险因素指标的权重大小.最后,应用风险评估理论分析工伤保险行业差别费率的运作机理,提出应用工伤赔付支出费用计算行业差别费率的数学公式,此公式原理清晰、操作方便,且有利于各统筹地区根据实际情况划分行业差别费率. 相似文献