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521.
田东石化工业园区污水处理工程设计规模为5000m3/d采用水解酸化+A/O工艺,该工艺对工业园区污水处理效果好,运行稳定.出水水质优于〈污水综合排放标准〉(GB8978-1996)一级标准,完全满足排入右江的要求.污水处理运行成本1.13元/m3.  相似文献   
522.
扎龙湿地浮游植物群落结构及多样性研究   总被引:3,自引:0,他引:3  
研究扎龙湿地浮游植物群落结构与多样性。经初步鉴定,共发现浮游植物60个分类单位,分别隶属于8门、10纲、14目、24科、41属、60种。浮游植物组成和生物量均显示扎龙湿地浮游植物为蓝绿藻型,多样性的分布具有时空差异,从Shannon-Weaver指数分布可以看出,扎龙湿地处于中营养状态,水质状况为丰水期>平水期>枯水期。  相似文献   
523.
This study provides a method for assessing a multiplicity of environmental factors in red spruce growth in the Great Smoky Mountains National Park (GSMNP) of Southeastern USA. Direct and indirect factors in the annual growth increment are first organized into a schematic input-output envirogram (ARIRS), and this information is then used to construct a simulation model (ARIM). The envirogram represents a structured conceptualization of most environmental factors involved in growth, as developed from relevant literature. This interdisciplinary synthesis distinguishes direct vs. indirect factors in growth and takes account of the systems ecology concept that indirect factors may be as important as or more important than direct ones in regulating growth. The ARIRS envirogram summarizes hierarchically organized, within- and cross-scale, local-to-global interactions, and its construction makes it obvious that growth is influenced by many cross-scale spatiotemporal interactions. More research on genecology is still needed to clarify the role of phenotypic plasticity and adaptive capacity in nutrient cycling, global change, and human disturbance.  相似文献   
524.
孙万国 《生态环境》2011,20(12):1966-1969
科学合理的制度安排必然是建立在对现存制度不合理的批判之上。湿地恢复补偿制度改革必须以现行湿地恢复补偿制度的现实性存在为基础和出发点,通过对现行湿地恢复补偿制度设计的目标和制度缺陷进行理性分析,为新的湿地恢复补偿制度设计与安排提供价值坐标,以保障湿地恢复补偿制度价值的实现。现行湿地恢复补偿制度规定存在着合法性、合理性和权威性等诸多悖论,成为湿地恢复补偿实践产生冲突的制度根源,并已构成当前环境友好型和资源节约型社会实践推进的严重障碍。  相似文献   
525.
利用ISSR分子标记技术对湖北省大贵寺国家森林公园野生青檀(Pteroceltis tatarinowii Maxim.)居群进行遗传多样性分析。用11条ISSR引物对6个青檀居群64个样品进行扩增,扩增片段长度在200bp至3000bp之间,检测到179个位点,其中多态位点165个,多态位点百分率(P)为92.14%。青檀在物种水平上的Nei基因多样性指数(胁)和Shannon信息指数∽分别为0.273和0.423,在居群水平上分别为0.225和0.343,显示出青檀有着较高的遗传多样性。居群间的遗传分化系数(Gsr)为0.192,表明青檀居群间存在着较大的遗传分化;UPGMA聚类分析表明遗传距离与海拔差距有一定的相关性,相邻海拔的青檀居群间遗传距离较近。不同海拔导致的异质生境可能是影响青檀居群遗传分化的主要原因。  相似文献   
526.
In biodiversity hotspots, there is often tension between human needs and conservation, exacerbated when protected areas prevent access to natural resources. Forest-dependent people may compensate for exclusion by managing unprotected forests or cultivating planted woodlots. Outside Bwindi Impenetrable National Park in Uganda, household wood product needs are high and population growth puts pressure on the environment. We investigated the role of privately and collectively managed woodlots in provisioning wood products and supporting local livelihoods. We found that households relied heavily on woodlots for daily needs and as resources during time of need. We also found that locally relevant social institutions, called stretcher groups, played a role in the management of woodlots, providing shared community resources. Privately and collectively owned woodlots support local livelihoods and wood product needs in the region. Long-term management of forests in Uganda should consider the value of woodlots and the mechanisms required to support them.  相似文献   
527.
碳(C)、氮(N)、磷(P)是土壤重要的营养元素,其生态化学计量特征可以反映土壤供肥能力和质量状况,在揭示生态系统稳态机制中具有重要作用.水盐环境对河口湿地生态化学计量特征具有重要影响,但土壤C、 N、 P生态化学计量特征对水盐环境变化的响应仍不清楚.以黄河口湿地为研究对象,采用土柱移位培养法,将淡水湿地土壤分别移位至不同潮滩部位(高潮滩、中潮滩和低潮滩)的盐沼湿地,研究水盐环境对C、 N、 P生态化学计量特征的影响.结果表明,移位23个月后,淡水湿地土壤含水量(SWC)和电导率(EC)与C、 N、 P生态化学计量特征均发生了不同程度的变化.土壤SWC在高潮滩和中潮滩降低(P<0.05),在低潮滩升高(P<0.05); EC在3种潮滩上均有不同程度的升高(P<0.05).土壤有机碳(TOC)和全氮(TN)在高潮滩显著降低(P<0.05),全磷(TP)则在中潮滩和高潮滩显著降低(P<0.05); C∶N在高潮滩和中潮滩及C∶P和N∶P在高潮滩显著降低(P<0.05); C、 N、 P生态化学计量比在低潮滩变化均不显著(P>0.05).水盐环境主要...  相似文献   
528.
正A wetland with attractive plants hosting birds and other wildlife is an esthetically pleasing prospect that is gaining popularity as a way of stabilizing or remediating metalcontaminated soils and sediment(Weber and Gagnon,2014;  相似文献   
529.
湖泊湿地是我国的重要湿地生态系统,具有许多经济价值和社会服务功能,合理开发和利用湖泊湿地资源有利于促进我国广大湖区的可持续发展。结合有关东部平原地区湖泊湿地的研究,提出该区湖泊湿地的恢复与可持续发展对策,指出湖泊湿地的恢复应坚持生态、经济和社会可持续发展的原则,并根据具体的生态环境状况来进行,旨在为恢复与保护湖泊湿地的实际操作提供科学依据。  相似文献   
530.
Economic impact analysis (EIA) of outdoor recreation can provide critical social information concerning the utilization of natural resources. Outdoor recreation and other non-consumptive uses of resources are viewed as environmentally friendly alternatives to extractive-type industries. While outdoor recreation can be an appropriate use of resources, it generates both beneficial and adverse socioeconomic impacts on rural communities. The authors used EIA to assess the regional economic impacts of rafting in Grand Canyon National Park. The Grand Canyon region of northern Arizona represents a rural US economy that is highly dependent upon tourism and recreational expenditures. The purpose of this research is twofold. The first is to ascertain the previously unknown regional economic impacts of Grand Canyon river runners. The second purpose is to examine attributes of these economic impacts in terms of regional multipliers, leakage, and types of employment created. Most of the literature on economic impacts of outdoor recreation has focused strictly on the positive economic impacts, failing to illuminate the coinciding adverse and constraining economic impacts. Examining the attributes of economic impacts can highlight deficiencies and constraints that limit the economic benefits of recreation and tourism. Regional expenditure information was obtained by surveying non-commercial boaters and commercial outfitters. The authors used IMPLAN input-output modeling to assess direct, indirect, and induced effects of Grand Canyon river runners. Multipliers were calculated for output, employment, and income. Over 22,000 people rafted on the Colorado River through Grand Canyon National Park in 2001, resulting in an estimated $21,100,000 of regional expenditures to the greater Grand Canyon economy. However, over 50% of all rafting-related expenditures were not captured by the regional economy and many of the jobs created by the rafting industry are lower-wage and seasonal. Policy recommendations are given for increasing the regional retention of rafting expenditures and for understanding both the beneficial and adverse impacts that accompany outdoor recreation in rural areas.  相似文献   
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