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391.
Agricultural water management is a complex decision-making problem involving multiple criteria of different nature as well as multiple decision agents with different interests. To handle this multiplicity of objectives and interests a pragmatic approach based on compromise programming is proposed in this paper. The methodology is applied to an agricultural water management problem in Tauste, Spain. Public, environmentalist and private decision makers are considered. The approach proposed reveals itself as a pragmatic alternative to other approaches based on aggregate utility functions with very sound theoretical underpinnings but with few possibilities of actually being put into practice. 相似文献
392.
Vinish Kathuria 《Environment, Development and Sustainability》2007,9(2):107-130
The common effluent treatment plants (CETPs) are being propagated as the policy response to circumvent the pollution problem
from the small-scale industries (SSIs), which abound in developing countries. The formation of the CETPs has been hailed as
a collective action or co-operative solution to a common problem involving all the agents responsible for pollution. This
paper investigated the desired criteria for designing an institution aimed at solving a common resource problem and factors
ensuring the smooth functioning or sustainability of the institution. The design criteria and factors are then tested on a
CETP set up in the Indian state of Haryana. The CETP, which was commissioned in 1997 had to be converted to a sewage treatment
plant (STP) as the collective arrangement collapsed. The criteria used in the present analysis are that of Ostrom’s [Governing the Commons. Cambridge, UK, Cambridge University Press, 1990] design principles, whereas the factors considered for sustainability are
the one suggested by Rawls [A Theory of Justice. USA, Harvard University Press, 1971]. The analysis indicates that the Kundli CETP failed in both counts as neither all the
design principles were met nor did the institution fulfil different sustainability criteria. The paper concludes with the
lessons that can be learnt from Kundli’s failure.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
393.
Siamak Rajabi Keith W. Hipel D. Marc Kilgour 《Journal of the American Water Resources Association》2001,37(3):533-546
ABSTRACT: A new screening approach is applied to a large‐scale multiple criteria water management problem to remove actions that cannot possibly be in the best subset. An inherent advantage of the approach is its ability to identify inferior actions by examining them individually, rather than within subsets. In a case study involving the selection of actions to address high water levels in the Great Lakes‐St. Lawrence Basin, two statistical indicators, the mode and the mean, are used to aggregate the opinions of experts and representatives of interest groups on the impacts of actions according to various criteria. Application of the screening approach shows that some of the proposed actions can be removed as they can never be in the optimal subset, thereby reducing the size of the problem. 相似文献
394.
通过筛选敌敌畏、马拉硫磷和对硫磷3种有机磷农药对水生生物的急性毒性数据和乙酰胆碱酯酶抑制效应数据,构建物种敏感度分布曲线进行了比较分析。结果表明,敌敌畏对水生生物的急性毒性和乙酰胆碱酯酶抑制效应的大小顺序为:酶体内抑制效应酶体外抑制效应急性毒性;马拉硫磷和对硫磷的乙酰胆碱酯酶抑制效应数据不足但趋势相似,顺序为:酶体内抑制效应急性毒性酶体外抑制效应。敌敌畏的急性毒性和酶体外抑制效应的5%危害浓度(HC5)分别为2.07μg·L~(-1)和1.53μg·L~(-1),两者相差1.4倍。在水质基准推导中,乙酰胆碱酯酶抑制效应数据对有机磷农药的水生生物基准具有重要的参考价值。 相似文献
395.
太湖生物区系研究及与北美五大湖的比较 总被引:4,自引:1,他引:3
研究太湖水生生物区系特征,分析各类生物区系的变化及其原因,并与北美五大湖相应的水生生物区系进行了比较. 结果表明:太湖共有水生生物146科442种,其中鱼类25科107种,占24.2%; 底栖动物21科66种,占14.9%; 浮游动物37科103种,占23.3%; 浮游植物29科81种,占18.3%; 水生植物34科85种,占19.2%. 总体上太湖各类水生生物的种数和科数差别都不大,鱼类和浮游动物稍多. 北美五大湖各类水生生物的种数分别为鱼类134种、底栖动物165种、浮游动物132种以及浮游植物1 456种,除浮游植物种类较多外,其他3类水生生物的种数与太湖大致相当. 五大湖鱼类以鲑科和鲤科鱼类为主体,分别占鱼类总数的18.7%和20.1%,其中除伊利湖外其他4个湖都是鲑科占优势; 太湖鱼类以鲤科为主体,占鱼类总数的56.1%,这是太湖鱼类区系的主要特征,也是我国淡水鱼类的主要特征,所以鲤科是我国水质基准推导的优先选择物种. 太湖和五大湖中鱼类、底栖动物和浮游动物3类生物所占比例差别不大. 相似文献
396.
397.
水质基准本土环节动物与水生昆虫受试生物筛选 总被引:2,自引:0,他引:2
作为水环境质量评价体系中重要的指示生物类别,水生环节动物和水生昆虫是水生生物基准研究中不可或缺的基准受试生物.参照美国水生生物基准技术指南, 选择我国广泛分布的10种本土环节动物和水生昆虫,搜集、筛选对各水生物种毒性最大的3种污染物,并进行水生生物敏感性分析. 在污染物毒性数据的物种敏感度分布中,若物种的累积概率小于30%则为较敏感,该物种可作为基准研究受试生物. 结果表明:不同生物对污染物敏感性存在差异,颤蚓对有机锡化合物、重金属,苏氏尾鳃蚓对重金属均较敏感;仙女虫、黄翅蜻、四节蜉、扁蜉对各类农药均较敏感;尾盘虫能够在一定程度上指示表面活性剂污染状况. 因此,环节动物颤蚓属、尾鳃蚓属、尾盘虫属、仙女虫属,水生昆虫黄翅蜻属、四节蜉属及扁蜉属均可作为水质基准研究中的受试生物. 相似文献
398.
为建立中国水环境生态学基准体系,并验证其合理性,于2011和2012年夏季,对辽河水系浮游植物群落结构特征进行了调查,并结合所收集到的资料,初步验证了辽河水系浮游植物生物多样性基准值的合理性.两次采样共检出6门169种及变种;细胞密度均值分别为4.91×106,7.04×106个/L,优势类群为硅藻和绿藻.共检出污染指示种59种,其中乙型中污指示种最多,为53种;检出优势种35种,主要为硅藻.综合各生物指标显示辽河水系夏季为富营养型中度污染水体.Shannon指数(H)在1.18~3.56之间,均未达到本文参考的基准值3.65,分析结果显示用于计算基准值所选取的参照点较为合适,通过分析辽河水系及我国其他一些河流的Shannon指数与水质状况,初步认为,该基准值偏高,建议辽河水系设定基准值的下限H=3.29. 相似文献
399.
不同温度和pH下氨氮对河蚬和霍甫水丝蚓的急性毒性 总被引:3,自引:0,他引:3
水环境中氨氮毒性与pH、温度等环境因子密切相关. 采用半静态方法研究不同pH和温度下氨氮对河蚬(Corbicula fluminea)和霍甫水丝蚓(Limnodrilus hoffmeisteri)的急性毒性效应. 结果表明:pH对氨氮毒性影响显著,其中NH3+NH4+对河蚬和霍甫水丝蚓的LC50(半致死浓度)随pH的增加而下降,其变化范围为11.78~83.82 mg/L,并且这2种水生生物对NH3+NH4+毒性的敏感性差异不大;当温度分别为20、25和30 ℃时,NH3+NH4+对河蚬的LC50分别为70.86、37.85和19.14 mg/L,对霍甫水丝蚓的LC50分别为65.88、42.73和21.21 mg/L,20 ℃时NH3+NH4+对河蚬及霍甫水丝蚓的LC50分别是30 ℃时的3.70和3.11倍. 表明水体pH和温度越高,氨氮的毒性作用越强. 通过比较氨氮水生生物基准中的FAV(最终急性值)和试验生物的LC50发现,我国现有的氨氮基准能够很好地保护本土水生物种河蚬和霍甫水丝蚓. 相似文献
400.
Marzena Ucherek 《国际发展与全球生态学杂志》2013,20(1):63-67
Current trends in the development of the world packaging market and the place of ecological tendencies in them suggest the need to analyse the present status of studies on the ecological assessment of packaging materials and packaging. The aim of this study is to present some aspects of ecological assessment of packaging. The methods and criteria of ecological assessment of packaging, including Life Cycle Analysis (LCA) and ecological classification of packaging proposed by COBRO (Polish Packaging Research and Development Centre) in Warsaw were used. The considerations presented in the paper related to the general assumptions of ecological assessment of packaging materials and packaging point to the complexity of the problem and, at the same time, to the immediate interest and importance of studies in this field, particularly in terms of implementing a specific environmental protection policy. 相似文献