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361.
Franois P. Brissette Robert Leconte Claude Marche Jean Rousselle 《Journal of the American Water Resources Association》2003,39(6):1385-1396
ABSTRACT: There is a general belief in the public eye that extreme events such as floods are becoming more and more common. This paper explores this hypothesis by examining the historical evolution of annual expected flooding damage on the Chateauguay River Basin, located at the border between the United States and the province of Quebec, Canada. A database of basin land use was constructed for the years 1930 and 1995 to assess anthropogenic changes and their impact on the basin's hydrology. The progressive modification of the likelihood of a flooding event over the same period was then investigated using homogeneity and statistical tests on available hydrometric data. The evolution of the annual expected flooding damage was then evaluated using a coupled hydrologic/hydraulic simulator linked to a damage analysis model. The simulator and model were used to estimate flooding damage over a wide range of flooding return periods, for conditions prevailing in 1963 and 1995. Results of the analysis reveal the absence of any increasing or decreasing trend in the historical occurrence of flooding events. However, a general increase in the annual expected flooding damage was observed for all studied river sections. This increase is linked to an historical increase in damages for a given flooding event, and is the result of unbridled construction and development within the flood zone. To assess for future trends, this study also examined the potential impacts linked to the anticipated global warming. Results indicate that a significant increase in seasonal flooding events and annual expected flooding damage is possible over the next century. In fact, what is now considered a 100‐year flooding event for the summer/fall season could become a ten‐year event by the end of this century. This shows that potential future impacts linked to climate change should be considered now by engineers, land planners, and decision makers. This is especially critical if a design return period is part of the decision making process. 相似文献
362.
ABSTRACT The introduction of the new biomass industry exerts influences that change the interactions among economic sectors by drawing the resources for generating electricity, pricing alterations from the existing market and competitively selling electricity to the power grid. These influences should be described and identified to ensure the benefits to the local economy. In this article, we deem to test the potential of hybrid I-O analysis to analyze the economic impacts and address the change in characteristics of the economic impacts of the biomass power plant. The resource utilization data from the existing biomass power plant located in Kochi Prefecture (Japan) is collected and then analyzed by a hybrid input-output (I-O) analysis. We found that (1) the use of cutoff function could determine the new economy’s structure included the biomass power plant where the allocation of resource in the economy is changed according to the consumption and production of the biomass power plant, (2) The power plant increases the total production of Kochi prefecture’s economy, and this benefit overthrows the negative effect of the loss of resource demand of the existing economic sectors. The use of the hybrid I-O to forecast the economic impacts on the local economy could enhance the decision made by the policymaker. 相似文献
363.
重大自然灾害中灾害链对灾情的巨大放大、累加作用,使灾害链研究备受关注。基于灾害系统理论,以中国汶川"5.12"地震灾害和日本福岛"3.11"地震灾害为例进行了地震灾害链梳理和区域对比,并探讨了不同灾害系统下,孕灾环境和承灾体对灾害链致灾成灾的影响。通过构建承灾体脆弱性与灾情累积关系的概念模型,阐述了灾害链对灾情的放大机制。研究表明:汶川地震具有陆地山区灾害链特征,主要灾害链为地震→崩塌/滑坡→(泥石流→)堰塞湖灾害链和地震→结构破坏→设施受损灾害链;日本地震具有海洋岛屿灾害链特征,主要灾害链为地震→海啸→核事故灾害链、地震→(海啸→)结构破坏→火灾/生命线系统损毁灾害链和地震→滑坡/火山/水库溃坝灾害链等;两场地震灾害中灾害链的成因及灾害链对灾情的放大过程差异显著;福岛地震灾害链危害巨大,使灾情在其他相关国家放大。 相似文献
364.
A 60-year sedimentary record of natural and anthropogenic impacts on Lake Chenghai, China 总被引:1,自引:0,他引:1
Fengyu Zan Shouliang Huo Beidou Xi Jingtian Zhang Haiqing Liao Yue Wang Kevin M. Yeager 《环境科学学报(英文版)》2012,24(4):602-609
Recent sediments from Lake Chenghai, China, were investigated at high temporal resolution to trace both natural and anthropogenic effects on the lake using total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), organic phosphorus (Po), inorganic phosphorus (Pi) and organic carbon and nitrogen stable isotopes (δ13Corg and δ15N) in a 137Cs-dated sediment core. The results indicated that the sedimentary record covers the last 60 years, during which the lake had undergone apparent changes in nutrient sources and productivity in response to nutrient loading. Prior to the late 1980s, the nutrient contents in sediments mainly originated from algae and lake productivity was relatively stable. Since the late 1980s, increasing TOC, TN and TP concentrations together with the change of δ13Corg and δ15N suggested anthropogenic perturbations in nutrient loading and lake productivity. Endogenic nutrients derived from algae and anthropogenic inputs were two important sources of sedimentary nutrients. The anthropogenic nutrients mainly originated from the discharge of industrial wastewater and artificial cultivation of Spirulina after the middle 1980s, and domestic wastewater discharged from Yongsheng County since 1993. 相似文献
365.
煤层气勘探中的生态环境影响及保护对策 总被引:2,自引:0,他引:2
煤层气勘探开发不仅可以消除煤层气对矿井和矿工带来的危害,还可以为社会提供一种洁净、使用方便的新能源和作为化工工业的优质原料。本文通过对山西晋西北煤田煤层气勘探过程进行分析,针对煤层气勘探活动的特点和可能造成对生态环境的影响和破坏,提出了减缓这些影响和破坏的综合防治对策。 相似文献
366.
可持续发展与累积影响评价 总被引:12,自引:0,他引:12
阐述可持续发展概念与内涵,分析可持续发展要求下传统环境影响评价制度的弊端。累积影响评价在概念、目标与方法上与可持续发展一致,探讨了累积影响评价的特点与必要性。 相似文献
367.
气候变化对于桥水库总磷与溶解氧的潜在影响分析 总被引:1,自引:0,他引:1
对于桥水库1992~2011年20年间的气候要素和水质指标进行数理分析,探求气候变化对该库总磷与溶解氧的潜在影响.首先,根据气温MK突变检验和距平分析,将研究期划分为1992~2001低温低风速年和2002~2011高温高风速年两个时段;其次,在应用上改进非参数回归分析法,图示比较两个时段各要素非线性趋势,获取气候要素在两个时段间的季节性变化规律;最后,通过比较两个时段气候要素对水质指标潜在影响的可能性,利用双k值潜在影响判别法揭示潜在影响规律.结果表明,气候要素在各季节的变化有可能对水库总磷和溶解氧浓度造成潜在影响.通过探讨入库负荷和库总磷浓度的年际变化差异,以及观测高温年、低温年水生植物春季物候和总磷浓度,证实春季气温升高降低了水库总磷浓度.该研究为探究气候变化对于桥水库水质的影响机制和规律提供参考依据. 相似文献
368.
369.
废弃餐饮油脂的资源化利用是关乎公众健康和环境保护的重要举措.目前我国废弃餐饮油脂炼制生物柴油的环境效益尚不明晰、国家政策模糊,相关产业发展滞缓.本研究以国内废弃餐饮油脂炼制生物柴油的典型企业为例,利用GaBi软件对废弃餐饮油脂的收集、预处理、酯化和运输等过程全生命周期阶段的资源环境影响进行系统核算,评估其环境效益,以期为国家生物柴油行业发展和相关政策制定提供科学依据.研究结果表明:①整个生命周期过程中,酯化阶段的环境影响最大,各指标占比为52.91%~96.05%,其环境影响主要是由燃煤、用电和甲醇消耗引起;②敏感性分析结果显示,燃煤、用电、甲醇消耗和收集距离的变化对整个生命周期环境影响结果有着较大影响;③废弃餐饮油脂炼制的生物柴油生命周期化石能源消耗16406 MJ·t~(-1)、温室气体排放815 kg CO_2 eq·t~(-1),与石化柴油相比,具有较好的节能和温室气体减排效益. 相似文献
370.