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221.
我国境内石油行业总体呈现原油开采量上升的态势,为之付出的经济和生态成本也越来越大。开展我国境内石油资源资产负债表的编制工作对于摸清我国石油资源的家底、评估我国石油资源开采的经济—资源—环境综合成本、探讨我国石油开采战略的合理性具有重要的意义。本文首先探讨了石油资源资产负债表的编制方法和框架,构建了集"生态系统服务"、"环境污染"和"资源消耗"三位于一体的"生态负债"账户。其次,收集并整理了重要的污染物处理成本和生态系统服务的价值评估成果,构建了价值化因子数据表。最后,基于2012年数据尝试编制了目前我国的第一份石油资源资产负债表。结果显示,(1)2012年末,我国石油资源的资产总额为1.47×109万元,负债总额为9.03×107万元,所有者权益为1.38×109万元;(2)石油资源资产总额占到当年政府资产总额的14.43%,占政府资源性资产比重达31.12%;(3)石油行业的资产负债率为6.15%,负债权益比达到了6.56%;(4)"生态系统服务"构成了负债的最大比重,达到了98.16%。总的来说,我国石油开采行业整体处于"高资产、高负债、强生态压力和弱可持续性"的状态。从这份资产负债表我们可以看出,我国境内石油开采的生态成本不容忽视。随着资源的不断开发,石油开采的边际生态成本只会越来越大,因此,能指向经济和生态两方面的综合成本应该取代账面成本成为政府进行石油资源开发的决策依据之一。此外,要落实石油资源资产负债表对于生态保护的实际指导意义,我们建议应该将石油资源开采的资产负债率、负债权益比等指标纳入官员的绩效考核体系。  相似文献   
222.
The interprovincial trade embodied carbon emissions plays an important role in the national emission reduction target among China’s provinces. Furthermore, it will affect the smooth start-up of the national carbon trade market as well as the implementation of targets in 2030 for dealing with the climate change. Based on constructed MRIO model, this paper analyzes the embodied carbon emission trade flows among Beijing, Tianjin, Hebei and surrounding regions such as Shanxi, Shaanxi, and Inner Mongolia. The results indicate that six provinces have formed different patterns of carbon trade balance, where Beijing, Tianjin, and Hebei provinces are in a deficit position, while the other three provinces are in a surplus position. Beijing, Tianjin, and Hebei have transferred part of the carbon emissions to the other three provinces, which shows greater heterogeneity among various provinces and provincial different sectors. On basis of the conclusions, this paper puts forward some suggestions on provincial decomposition, responsibility distribution, and provincial collaborative reduction for national emission reduction targets.  相似文献   
223.
环境容量资产的核算是自然资源资产负债表编制中的主要组成部分。本文基于环境容量提出京津冀地区环境资产负债表编制方法,阐明该地区环境资产负债表的编制内容、核算范围以及编制路径,对2013年该地区及13个城市的环境容量资产进行核算,并编制了实物量资产负债表。在此基础上,提出了京津冀地区降低环境资产负债的政策建议,指出我国环境资产负债核算工作逐步规范化、制度化的方向。结果表明,京津冀地区大气及水环境容量均处于严重负债状态,其中,主要大气污染物SO2、NOx和PM2.5环境容量资产负债率分别为-235%、-263%和-316%,主要水污染物COD和NH3-N环境容量资产负债率分别为-414%和-850%。本文研究成果可为京津冀地区资源环境与经济发展决策提供科学基础,同时也可为其他地区开展环境资产核算研究提供参考。  相似文献   
224.
环境多介质空间分异模型能够对持久性有机污染物(POPs)在环境多个介质中空间尺度上的迁移转化和分配过程进行准确、细致和接近真实的描述,是进行POPs的环境多介质归趋模拟和环境风险评价的重要工具.将环境多介质空间分异模型分为环境多介质质量平衡空间区划模型和大气化学传输模型,对目前几种常用的环境多介质空间分异模型GLOBO...  相似文献   
225.
Abstact Simulating hydrologic processes in geologically complex environments is a difficult scientific task since it incorporates high level of uncertainty. Many studies have attempted to accurately quantify the rainfall-water level elevation relationship in freshwater bodies so as to predict flooding and drought events. For this purpose several types of models have been implemented including distributed, black box and conceptual models that often provide efficient results, depending on the availability of reliable data as well as on the level of understanding of the system. Nevertheless, in the particular effort, three different models have been used to describe the relationship between rainfall and water level elevation in Trichonis Lake during the period 1951–1997. A Transfer Function model, a Dynamic Linear Regression and a physically based model, consisting of the lake's water budget equation, its Digital Bathymetric Model and GIS algorithms. These models have been tested to assess their efficiency and applicability in a karstic environment and the aim of the study was to find the best modeling option for developing sustainable water management plans and establishing a flooding/drought warning system in the particular lake catchment. The results indicated that in areas with geologically complex conditions, simple, physically-based models operate better than mechanistic models which usually cannot describe adequately the complexity of the system  相似文献   
226.
通过对辽河油田公司有关企业开展清洁生产审核,总结出了燃料锅炉量化管理的方法。在自然对流烘干室改造、碱液浓缩炉改造、燃煤锅炉设计效率核准等实例中,该方法可昭示能耗大的"瓶颈"部位,进而为企业制定节能方案、提出具体的节能改造措施提供了科学依据。实践证明:实施锅炉量化管理是企业挖掘节能潜力的重要途径。  相似文献   
227.
A mass balance model for mercury based on the fugacity concept is applied to Lake Superior, Lake Michigan, Onondaga Lake and Little Rock Lake to evaluate model performance, analyze cycling of three mercury species groups (elemental, divalent and methyl mercury), and identify important processes that determine the source-to-concentration relationship of the three mercury species groups in these lakes. This model application to four disparate ecosystems is an extension of previous applications of fugacity-based models describing mercury cycling. The model performs satisfactorily following site-specific parameterization, and provides an estimate of minimum rates of species interconversion that compare well with literature. Volatilization and sediment burial are the main processes removing mercury from the lakes, and uncertainty analyses indicate that air-water exchange of elemental mercury and water-sediment exchange of divalent mercury attached to particles are influential in governing mercury concentrations in water. Any new model application or field campaign to quantify mercury cycling in a lake should consider these processes as important.  相似文献   
228.
Ninety-six riverine runoff samples collected at eight major outlets in the Pearl River Delta (PRD), South China, during 2005-2006 were analyzed for 17 brominated diphenyl ether (BDE) congeners (defined as Σ17PBDE). Fourteen and 15 congeners were detected, respectively, in the dissolved and particulate phases. These data were further used to elucidate the partitioning behavior of BDE congeners in riverine runoff. Several related fate processes, i.e. air-water exchange, dry and wet deposition, degradation, and sedimentation, within the Pearl River Estuary (PRE), were examined to estimate the inputs of Σ10PBDE (sum of the target BDE congeners, BDE-28, -47, -66, -85, -99, -100, -138, -153, -154, and -183) and BDE-209 from the PRD to the coastal ocean based on mass balance considerations. The results showed that annual outflows of Σ10PBDE and BDE-209 were estimated at 126 and 940 kg/year, respectively from the PRE to coastal ocean. Besides sedimentation and degradation, the majority of Σ10PBDE and BDE-209 discharged into the PRE via riverine runoff was transported to the coastal ocean.  相似文献   
229.
泥石流滩地是山区宝贵的土地资源,其农业资源化开发与利用对促进当地社会经济发展和生态环境改善具有重要意义。以蒋家沟流域为例,在野外调查、遥感解译和实验分析的基础上,阐述了泥石流滩地农业资源化的原则和依据,建立了人畜 土地载荷平衡模型,分析了滩地开发利用的依据、效益和途径,并探讨了泥石流滩地未来农业资源化的思路和对策。研究结果表明:(1) 建立的人畜 土地载荷平衡模型反映了流域生态环境特征,能有效评价滩地开发利用的生态效益;(2)流域滩地农业资源化每年可产生500多万元的经济效益,除满足全流域6 418人的粮食需求外,还可提供338 t商品粮,是促进当地脱贫致富和社会经济发展的重要途径;(3)泥石流滩地既是宝贵的土地资源又是灾害的场所,其开发与利用可有效缓解山区人地矛盾,具有良好的生态效益,但需要在加强灾害防治和防灾减灾意识的基础上,进行深度农业资源化开发.  相似文献   
230.
Lake Toolibin, an ephemeral lake in the agricultural zone of Western Australia, is under threat from secondary salinity due to land clearance throughout the catchment. The lake is extensively covered with native vegetation and is a Ramsar listed wetland, being one of the few remaining significant migratory bird habitats in the region. Currently, inflow with salinity greater than 1000 mg/L TDS is diverted from the lake in an effort to protect sensitive lakebed vegetation. However, this conservative threshold compromises the frequency and extent of lake inundation, which is essential for bird breeding. It is speculated that relaxing the threshold to 5000 mg/L may pose negligible additional risk to the condition of lakebed vegetation. To characterise the magnitude of improvement in the provision of bird breeding habitat that might be generated by relaxing the threshold, a dynamic water and salt balance model of the lake was developed and implemented using Monte Carlo simulation. Results from best estimate model inputs indicate that relaxation of the threshold increases the likelihood of satisfying habitat requirements by a factor of 9.7. A second-order Monte Carlo analysis incorporating incertitude generated plausible bounds of [2.6, 37.5] around the best estimate for the relative likelihood of satisfying habitat requirements. Parameter-specific sensitivity analyses suggest the availability of habitat is most sensitive to pan evaporation, lower than expected inflow volume, and higher than expected inflow salt concentration. The characterisation of uncertainty associated with environmental variation and incertitude allows managers to make informed risk-weighted decisions.  相似文献   
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