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971.
浮游植物是水生态系统中最重要的组成部分,因其对水环境变化敏感而常被用于指示水环境状态,但其对环境的响应受分类方法的影响.为了解洞庭湖浮游植物种群(门、属)和功能群(FG)两种分类法对环境的驱动响应特征和适用性,于2019年3~12月分水期对该湖共进行了4次采样,比较分析了浮游植物种群和功能群的分布特征及其与环境因子的响应关系,并对比了TLI指数、 Shannon-Wiener指数、Q指数等评价方法在洞庭湖的适用性.结果表明,洞庭湖共检出浮游植物6门61属,可划分为23个功能群和9个优势功能群,功能群演替趋势为P/MP/D(3月)■月)■月)■(12月).层次分割结果表明,洞庭湖浮游植物的种群分布与变化受环境因子的驱动大于空间驱动;影响浮游植物种群和功能群的主要环境因子为水温(WT)、高锰酸盐指数、溶解氧(DO)、电导率(Cond)、水位(WL)和总磷(TP),环境因子对两者的独立解释性排序相差不大.RDA分析表明,浮游植物功能群对环境因子的响应要优于浮游植物种群.综合对比分析发现,利用Q指数进行水质评价在洞庭湖水体有较好的适用性.  相似文献   
972.
The study described in this article incorporates stakeholders' views on aquatic invasion processes and combines expert analysis with information from field work into an evaluation exercise. Management scenarios are designed based on available technical data and stakeholders' perceptions. These scenarios are evaluated using the Social Multi-Criteria Evaluation framework employing the NAIADE model. Two evaluations are carried out, technical and social. Social acceptance of different management scenarios, distribution of costs and benefits, and attribution of responsibility are discussed. The case study was carried out on Lake Izabal, a body of water connected to the Caribbean Sea in Northeastern Guatemala. In 2000, local fishermen reported the presence of an alien species in the lake, the macrophyte Hydrilla verticillata. Two years later, this alien species was established around the entire lakeshore, damaging the ecosystem, endangering native species and the subsistence of local inhabitants through impacts on transportation, fishing practices, and tourism.  相似文献   
973.
This paper presents an analysis of the main environmental impact factors (noise, vibration, fumes, dust, vehicle traffic) associated with marble quarrying and processing in the Orosei industrial area and their effects. Solutions are also proposed to prevent, mitigate and, where possible, eliminate the impact on the environment. Using three-dimensional topographic models, the authors simulated quarry and industrial processing development, with projections over the next 10, 30 and 50 years. The aim of these simulations was to establish land management planning guidelines for the optimal and environmentally sustainable development of the Orosei Marble industrial area. Lastly, careful quarry development planning is important both for enhancing LCA and for improving production processes through sustainable technologies that yield green label products meeting environmental performance standards.  相似文献   
974.
The combined influence on the environment of all projects occurring in a single area is evaluated through cumulative impact assessments (CIA), which consider the consequences of multiple projects, each insignificant on its own, yet important when evaluated collectively. Traditionally, future human activities are included in CIA using an analytical platform, commonly based on complex models that supply precise predictions but with reduced accuracy. To compensate for the lack of accuracy in current CIA approaches, we propose a shift in the paradigm governing CIA. The paradigm shift involves a change in the focus of CIA investigations from the detailed analysis of one unlikely future to the identification of the patterns describing multiple potential future changes in the environment. To illustrate the approach, a set of 144 possible and equally likely futures were developed that aimed to identify the potential impacts of forest harvesting and petroleum drilling on the habitat suitability of moose and marten in northeast British Columbia, Canada. The evolution of two measures of habitat suitability (average habitat suitability index and surface of the stands with habitat suitability index >0.5) revealed that the human activities could induce cycles in the habitat dynamics of moose and marten. The planning period of 100 years was separated into three distinct periods following a sinusoidal pattern (i.e., increase - constant - decrease in the habitat suitability measures). The attributes that could induce significant changes in the assessment of environment are the choice of harvesting age and species.  相似文献   
975.
Several models have been developed to assess the biological integrity of aquatic systems using fish community data. One of these, the target fish community (TFC) model, has been used primarily to assess the biological integrity of larger, mainstem rivers in southern New England with basins characterized by dispersed human activities. We tested the efficacy of the TFC approach to specify the fish community in the highly urbanized Charles River watershed in eastern Massachusetts. To create a TFC for the Charles River we assembled a list of fish species that historically inhabited the Charles River watershed, identified geomorphically and zoogeographically similar reference rivers regarded as being in high quality condition, amassed fish survey data for the reference rivers, and extracted from the collections the information needed to define a TFC. We used a similarity measurement method to assess the extent to which the study river community complies with the TFC and an inference approach to summarize the manner in which the existing fish community differed from target conditions. The five most abundant species in the TFC were common shiners (34%), fallfish (17%) redbreast sunfish (11%), white suckers (8%), and American eel (7%). Three of the five species predicted to be most abundant in the TFC were scarce or absent in the existing river community. Further, the river was dominated by macrohabitat generalists (99%) while the TFC was predicted to contain 19% fluvial specialist species, 43% fluvial dependent species, and 38% macrohabitat generalist species. In addition, while the target community was dominated by fish intolerant (37%) and moderately tolerant (39%) of water quality degradation, the existing community was dominated by tolerant individuals (59%) and lacked intolerant species expected in the TFC. Similarity scores for species, habitat use specialization, and water quality degradation tolerance categories were 28%, 35% and 66%, respectively. The clear pattern of deviations from target conditions when observing fish habitat requirements strongly suggests that physical habitat change should be a priority for river enhancement in the Charles River. Comparison of our target and existing fish communities to those from a comprehensive study of Northeastern fish assemblage responses to urban intensity gradients revealed very similar results. Likewise, comparison of our TFC community and affinity scores to those of other TFCs from similar regions also yielded similar results and encouraging findings. Based on the positive results of these comparisons, the utility of the findings from the inference approach, and the widespread adoption of the TFC in the Northeast US, it appears that the TFC approach can be used effectively to identify the composition of a healthy fish community and guide river enhancements in both highly urbanized and non-urbanized streams and rivers in the Northeast US.  相似文献   
976.
任静  于鲁冀 《四川环境》2011,30(6):149-154
改革开放以来,在我国经济快速发展的同时,产生了巨大的环境问题,为此,原国家环保总局审时度势,开展了创建国家环境保护模范城市的活动。本文对“创模”考核指标的调整情况进行概括,从总体情况、所属行政区、所属行政区级别、面积4个方面对目前“环保模范”城市状况进行了深入地分析,并对日后的“创模”工作进行了展望。  相似文献   
977.
目的是建立粉尘职业卫生监督量化分级管理指标体系,为企业的粉尘职业危害防治提供依据。对象与方法是以59名国内职业卫生领域专家为研究对象。通过编制的调查表,让专家依据各指标的重要程度打分。国内职业卫生领域符合条件的专家以电子邮件方式发送调查问卷70份,收回调查表59份。利用变异系数法,计算每一指标的平均分、变异系数和满分比,评价信度和效度,最终筛选确定粉尘企业职业危害监督量化分级管理的指标体系。结果如下,59名专家积极系数84.3%,8项一级指标和69项二级指标的平均值均超过2.5,变异系数均在50%以下,满分比均介于0-1之间,8项一级指标的克朗巴赫值均大于0.6,相关系数介于0.249-0.705之间。除预防措施和粉尘危害项目存在的问题外,其余均具有统计学意义。结论为企业粉尘职业危害监督量化分级管理指标体系经筛选包括8项一级指标和69项二级指标。  相似文献   
978.
本文以平遥县城及周边区域环境空气质量监测结果为依据,采用具有全局优化的遗传算法(GA)对平遥县及周边区域大气环境质量污染现状进行评价。用大气污染危害指数的普适公式和参数优化后的污染危害指数公式确定污染危害指数的取值范围与评价级别之间的对应关系,由此得出较符合平遥县及周边区域实际的评价结果,同时针对具体情况对此结果进行简单的分析。  相似文献   
979.
中部六省区制造业地理集中度分析   总被引:1,自引:0,他引:1  
中部六省区在我国经济社会发展格局中占据重要地位.采用Eillison和Glaser设计的公式计算了中部六省区制造业17个行业从2007-2010年间的地理集中指数.通过对地理集中指数的分析发现,中部六省区制造业存在“小范围小幅度集中,大范围大幅度扩散”现象,且集中主要存在于化学纤维制造业、化学原料及化学制品制造业和专用设备制造业这些技术和资本密集型行业.从制造业17个行业扩散大于集中的现象可见,中部六省区目前还处于聚集效应的下降阶段.  相似文献   
980.
以可持续发展相关理论为基础,利用系统工程的理论和方法建立了河北省县域可持续发展指标体系及其评价标准,并在全省范围应用,对全省136个县(市)可持续发展能力做出了评价。结合评价结果,阐述了河北省县域可持续发展能力的特征,提出了河北省县域可持续发展的方向和思路。  相似文献   
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