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991.
基层环境监测站承担着大量监测数据来源的责任,监测数据的质量不容忽视,但基层环境监测站普遍存在对仪器期间核查忽视的问题,严重影响数据质量的可靠程度,所以应根据仪器的性能和使用情况,在规定的时间间隔内,使用相应的核查方法,对仪器进行期间核查,及时预防和发现不合格的仪器并避免误用,保证监测结果持续的准确性、有效性,以维护环境监测站和客户的权益。  相似文献   
992.
From the perception of human populations, we can assess the changes occurring in certain landscapes and the factors that cause those changes. Such studies have proven helpful in increasing the knowledge of the history of a landscape, recognizing past formations and projecting its future. Our research objective was to determine how a landscape dominated by the palm tree Attalea speciosa, a species of ecological, economic, and cultural importance, has been changing over time by synthesizing and comparing historical documents and local perceptions. This study was conducted in Araripe Environmental Protection Area, Northeast Region, Brazil. To understand local landscape change, we interviewed active harvesters in four communities in which A. speciosa use has been documented. Historical documents were evaluated as a complement to the interview data. According to local informants, areas previously used for cultivation and animal husbandry that were abandoned or decimated by droughts in the region may have fostered the expansion of a monodominant A. speciosa forest. Furthermore, other forms of landscape management resulting from human population growth may also have affected the current and past distribution of this forest.  相似文献   
993.
草原生态补偿:生态绩效、收入影响和政策满意度   总被引:2,自引:0,他引:2  
草原生态保护补助奖励机制的第一轮实施期(2011-2015)即将结束,系统地评估草原生态保护补助奖励机制,对于完善下一期补助奖励机制具有重要的借鉴意义。本文利用2014年内蒙古自治区阿拉善左旗、四子王旗、陈巴尔虎旗三个旗县的470户牧户样本数据,从生态绩效、收入影响、政策满意度三个方面对草原生态补偿政策(即草原生态保护补助奖励机制)进行了评估。生态绩效评估结果表明:草原生态环境得到了一定的改善,草原利用方式更趋合理,平均牲畜超载率下降明显,但超载过牧的现状没有得到根本的转变,样本调研旗县2011-2014年减畜任务达成比例为42%,总体减畜任务达成情况一般。收入影响评估结果表明:平均每户理论收入影响为-8 607元,草原生态补偿标准偏低,需要在原有基础上提高35%;平均每户的实际收入影响为16 686元,牧民没有严格按照政策要求进行完全的减畜;草原生态补偿标准不只是单纯标准偏低的问题,同时也有标准差别化问题,需要在不同地区之间做出调整。政策满意度评估结果表明:草原生态补偿政策的满意度为57%,其中陈巴尔虎旗的政策满意度最高,为87%;四子王旗其次,为62-63%;阿拉善左旗最低,为18-32%。政策满意度与实际收入影响之间存在显著的相关关系,实际收入影响正向越大,政策满意度越高。牧民对草原生态补偿政策的政策满意度越高,并不意味着草原生态补偿的政策设计和执行就越好,政策满意度越高,实际收入影响正向越大,但生态效果可能不佳。  相似文献   
994.
分析了当前国内外几种渗滤液处理技术中存在的问题,以及渗滤液处理技术的发展方向。指出渗滤液处理技术应根据工程建设要求,并将渗滤液处理系统与垃圾焚烧系统结合起来确定,今后的发展方向和研究重点应放在渗滤液处理系统中的污泥处理系统、沼气净化及利用系统、膜系统浓缩液处理系统上。  相似文献   
995.
Acadia National Park was one of the 14 sites included in the Park Research and Intensive Monitoring of Ecosystems network (PRIMENet). For eight years the EPA monitored ultraviolet (UV) radiation at this site, with the National Park Service (NPS) sponsoring a total climate and air monitoring station. Under the auspices of PRIMENet, research projects were initiated that investigated the effects of UV on amphibians, determined watershed mass balances, and developed a model of deposition along an elevational gradient. The monitoring data and research results have been used by park management to protect vegetation and water resources from ozone and deposition. These data are now being used to develop a “vital signs” monitoring program under the NPS’ Inventory and Monitoring Program. These data sets have been used in regional, national and international programs to protect human health and resources from air pollution. Public outreach has been accomplished through web site resources and via the Schoodic Education and Research Center.  相似文献   
996.
Safe amendment rates (the predicted no-effect concentration or PNEC) of seven organic wastes were estimated from the species sensitivity distribution of a battery of soil biota tests and compared with different realistic amendment scenarios (different predicted environmental concentrations or PEC). None of the wastes was expected to exert noxious effects on soil biota if applied according either to the usual maximum amendment rates in Europe or phosphorus demands of crops (below 2 tonnes DM ha−1). However, some of the wastes might be problematic if applied according to nitrogen demands of crops (above 2 tonnes DM ha−1). Ammonium content and organic matter stability of the studied wastes are the most influential determinants of the maximum amendment rates derived in this study, but not pollutant burden. This finding indicates the need to stabilize wastes prior to their reuse in soils in order to avoid short-term impacts on soil communities.  相似文献   
997.
Selenium and total and organic mercury were determined in the liver and kidney of franciscana dolphin (Pontoporia blainvillei) incidentally caught in fishing nets along two Brazilian coastal areas (southeast and south). Regional differences in the concentrations of these contaminants were observed in P. blainvillei. Liver showed the highest organic and total mercury. In general, samples of individuals collected at the southern of Brazil had the highest concentrations of selenium and total and organic mercury. No significant gender differences were observed. Growth stage influenced the accumulation of these contaminants in both organs, and hepatic concentrations increased with the body length, according to the sampling area. Molar mercury and selenium concentrations in liver were significantly correlated, with a Se:Hg ratio close to 4. The among-site differences we found may be related to differences in preferred prey, bioavailability in the marine environment, environmental conditions, or these individuals may belong to distinct populations.  相似文献   
998.
高锰酸盐指数在线自动监测仪的现状与问题   总被引:4,自引:0,他引:4  
高锰酸盐指数在线自动监测仪,已在全国水质自动监测系统中得到广泛的应用,厂家对该产品生产日趋成熟,相关标准逐步出台,仪器性能基本达标。但在实际应用过程中,该仪器仍有许多问题需要进一步认识与改进。文中从标准溶液、终点判定、国家标准、干扰、比对、自动标定等几个方面,分析了该仪器存在的问题,并提出了相关建议。  相似文献   
999.
固定源废气监测工作的若干问题探讨   总被引:2,自引:0,他引:2  
从监测工况、测点位置、采样过程、结果计算等方面,结合实际经验,对大气固定污染源的监测工作中存在的一些疑难问题进行了探讨。  相似文献   
1000.
There is concern that elevated levels of selenium found in the source water of a newly formed wetland park in Las Vegas, Nevada, may have detrimental effects on local wildlife. In this study, we collected and analyzed water samples monthly for a three year period from the inflow and outflow of the system. We also gathered dominant aquatic plants and selected terrestrial plants and analyzed the water and plant tissues (root, shoot, leaf and flower) for selenium by high resolution Inductively Coupled Plasma Mass Spectrometer. Except for storm events and the introduction of an alternative low selenium content source water during summer low-flow conditions, selenium in the water was relatively stable. The concentration in the outflow tended to be slightly lower than the inflow. Concentrations of selenium in the dominant plant taxa in this wetlands were typical of ecosystems in the western United States and varied by taxa, tissue type, localized conditions (e.g., contact with selenium-laden water), and to a lesser extent, seasons. Selenium in the aquatic plant spiny naiad (Najas marina) was relatively high and may pose an ecological risk to wildlife during the late spring and summer. Additional work is underway investigating aquatic food chain accumulations of selenium as well as mass balance of selenium in the system.  相似文献   
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