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451.
Hughes, Robert M., Alan T. Herlihy, and Philip R. Kaufmann, 2010. An Evaluation of Qualitative Indexes of Physical Habitat Applied to Agricultural Streams in Ten U.S. States. Journal of the American Water Resources Association (JAWRA) 46(4): 792-806. DOI: 10.1111/j.1752-1688.2010.00455.x Abstract: Assessment of stream physical habitat condition is important for evaluating stream quality globally. However, the diversity of metrics and methods for assessing physical habitat condition confounds comparisons among practitioners. We surveyed 51 previously sampled stream sites (0.0-6.3 m wide) located in regions of row-crop agriculture in Oregon, California, North Dakota, South Dakota, Nebraska, Iowa, Minnesota, Pennsylvania, Maryland, and West Virginia to evaluate the comparability of four indexes of physical habitat condition relative to each other. We also compared the indexes to previously calculated indexes of fish and macroinvertebrate condition. The physical habitat indexes included the Stream Visual Assessment Protocol Version 2 of the Natural Resources Conservation Service, the qualitative habitat evaluation index of the Ohio Environmental Protection Agency, the rapid bioassessment protocol of the United States Environmental Protection Agency (USEPA), and a qualitative physical habitat index based on USEPA quantitative physical habitat measurements. All four indexes were highly correlated with each other, but low-to-moderately correlated with biotic index scores for fish and macroinvertebrate assemblages. Moderately high correlations occurred between some macroinvertebrate biotic index scores and quantitative metrics. We conclude that additional research is needed to increase the predictive and diagnostic capabilities of qualitative physical habitat indexes.  相似文献   
452.
关于建设项目环境影响评价问题的探讨   总被引:1,自引:0,他引:1  
论述了建设项目环境影响评价中存在的问题,提出在报告书编制中应改进的方面,并建议修改环境影响评价导则,探讨了环境影响报告书中技术审查形式。  相似文献   
453.
When substance substitution is implemented to reduce the target risk of production processes, countervailing risks may occur. The goal of this study is to analyze the risk trade-off relationships between organic solvents and aqueous agents in the case study of metal cleaning processes. Global environmental impacts and local risks were evaluated for the eight scenarios by life cycle and risk assessments, respectively. The results show that the contribution of the processes using chlorinated solvents to photochemical ozone creation, human toxicity, ozone depletion, and ecotoxicity was larger than processes using aqueous detergents, while the contribution of aqueous processes to eutrophication was larger than chlorinated processes. Neighbors’ health risk around a cleaning site using chlorinated solvents was sufficiently small in all scenarios, whereas ecological risk due to surfactants which are contained in aqueous detergents and emitted to the local aquatic environment should be reduced. Cleansing agents and process facilities should be selected on the basis of the comprehensive analysis of risk trade-off relationships for feasible and cleaner production.  相似文献   
454.
Life Cycle Assessment (LCA) was applied to two smallholder milk production systems in Peru in order to evaluate the environmental burden of milk produced in each. An Andean highland milk production system where livestock feeding is restricted to permanent pastures supplemented with on farm grown ryegrass-clover was opposed to a coastal system with dairy cows fed a diet consisting of fodder maize and purchased concentrate. Milk production levels (kg/cow day) differed considerably with 2.57 for the highland and 19.54 for the coastal system. A Life Cycle Inventory was calculated for the functional unit of 1 kg energy corrected milk (ECM) and the environmental impacts global warming, acidification and eutrophication were estimated for 1 kg ECM, 1 ha and 1 animal, considering the multi-functionality of the system. The highland system was characterized by a high land use (23.1 m2a/kg ECM vs. 1.71 m2a/kg ECM at the coast). Irrigation water and energy were on the other hand used to a much higher amount at the coast (7291 l/kg ECM and 8791 MJ/kg ECM, respectively) than in the highlands (848 l/kg ECM and 0.20 MJ/kg ECM). Global warming potential, acidification and eutrophication were higher for 1 kg ECM produced in the highlands than at the coast by 10.6 kg CO2 equivalents, 6.58 g sulfur dioxide equivalents and 10.63 g phosphate equivalents, respectively. Nevertheless, 5220 kg CO2 equivalents more were emitted per animal at the coast than in the highlands. Also acidification and eutrophication were estimated to be on average 6 and 4 times higher at the coast compared to the highlands when expressed for the functional units of 1 ha and 1 animal.

Results

Whereas livestock is mainly responsible for impacts on the environment in the highlands, at the coast both livestock related emissions and forage cultivation play an important role. Furthermore CO2 releases from soybean cultivations heavily contribute to total emissions. Sensitivity analysis indicates that for dairy systems relying on crop by-products as feed the choice of the allocation method is a crucial point in a LCA study. Based on the results of this study, strategies in order to reduce the environmental burden of milk production should focus on an increase of production levels and a reduction of methane emissions from enteric fermentation in the highlands and a modification of the concentrate components replacing soya as the protein source at the coast.  相似文献   
455.
The three basic principles of sustainable development, relating to ecology, economy and society, have long been embedded within national and international strategies. In recent years we have augmented these principles by a further seven considerations giving rise to the so-called 10-tenets of sustainable management. Whilst theoretically appealing, discussion of the tenets to date has been largely generic and qualitative and, until the present paper, there has been no formal and quantitative application of these tenets to an actual example. To promote the concept of successful and sustainable environmental management there is the need to develop a robust and practical framework to accommodate value judgements relating to each of the tenets. Although, as originally presented, the tenets relate specifically to management measures, they may also be applied directly to a specific development or activity. This paper examines the application of the tenets in both of these contexts, and considers their incorporation into an assessment tool to help visualise and quantify issues of sustainability.  相似文献   
456.
对荒漠生物质气化发电进行LCA评价,建立评价模型,在评价过程中选用了燃煤发电系统为参照.研究结果表明,生物质利用过程没有CO2的排放,整个发电周期中仅原料的生产、运输以及预处理过程消耗能量导致CO2排放,因此生物质气化发电方案的排放量远远小于燃煤方案,减排量达到了87%-94%.生物质发电与燃煤发电相比,对环境污染降低程度的总指数为3.68.生物质能源的开发大大削减了化石能源利用带来的环境污染问题,同时也能够缓解能源危机.  相似文献   
457.
我国现行大气环境影响预测评价模型存在以下几个问题:大气混合层高度求算偏低;稳定条件下大气扩散计算结果不合理;模型未考虑非扩散因素影响(干湿沉积、化学转化);非正常排放模型在小风、静风条件下计算结果偏大;熏烟模型计算的不可操作性等。本文针对这些问题提出相应的改进方法,并进行了实例计算。  相似文献   
458.
阐述了规划环境评价中公众参与的意义和作用 ,结合沈阳市浑南新区规划环境评价对规划环境评价公众参与的方式方法及相关问题作了探讨  相似文献   
459.
阐述了替代方案的内涵和作用,分析了城市交通规划EIA的重要性,对城市交通规划EIA中替代方案的确定程序与分析比较方法、公众参与替代方案确定和分析过程中的作用等内容进行了探讨。  相似文献   
460.
The main purpose of industrial ecology is to evaluate and minimize impacts from economic activities of human society. Tourism as one economic activity, results in a full range of environmental impacts, but few applications of industrial ecology to tourism management have previously been discussed. Life cycle assessment (LCA) is used in this research to explore environmental impacts of island tourism, and then the environmental loads per tourist per trip can be found. Penghu Island in Taiwan is taken as an example to examine this new approach. Various environmental loads in transportation, accommodation, and recreation activity sector are all inventoried and calculated here. In summary, per tourist per trip uses 1606 MJ of energy, 607 L of water, and emits 109,034 g of CO2, 2660 g of CO, 597 g of HC, 70 g of NOx. In addition, per tourist per trip also discharges 416 L of wastewater, 83.1 g of BOD, and 1.95 g of solid waste. In terms of energy use, the transportation consumes the largest energy (67%); in particular, the airplane sector. Moreover, per Penghu tourist results in more environmental loads than local people; for example, the amount of solid waste discharge per tourist is 1.95 kg per day, while that of per local people is 1.18 kg. Finally, the advantages and limitations of such LCA approach are also discussed.  相似文献   
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