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991.
基于信息扩散与自助法的旱灾风险评估模型──以安徽为例 总被引:4,自引:0,他引:4
旱灾风险管理是抗旱减灾的科学手段、干旱及旱灾研究的重要方向,定量评估旱灾风险是旱灾风险管理的核心内容。为降低各种不确定性因素影响下旱灾风险评估结果的误差,提高结果的可靠性,提出运用信息扩散法估计旱灾损失的超越概率,结合自助法的区间估计算法,建立基于信息扩散与自助法的灾害风险评估模型,用不同置信水平下旱灾损失对应超越概率的置信区间来反映旱灾风险。将该模型运用于安徽省农业易旱地区干旱灾害风险评估,计算并确定在置信水平为0.75时安徽省易旱地区的旱灾风险区间评估结果合理、可靠,可为抗旱规划提供科学的决策依据。 相似文献
992.
根据辽宁省1976-2006年逐日降水和暴雨灾害损失数据,基于自然灾害风险理论,利用PPD(可能性-概率分布),分析不同等级暴雨发生的可能性;通过建立灾损指标体系获得暴雨灾损指数,结合Arc GIS技术,进行了辽宁省暴雨灾害风险评价与区划。结果表明:1辽宁省暴雨发生的可能性,随暴雨等级的增加而降低,主要发生一到四级暴雨,五级暴雨很少见,而发生2~5级暴雨概率基本由东南向西北递减(一级由西北向东南递减);2全省而言,暴雨灾害损失及风险与暴雨发生可能性区域分布特征总体吻合,即呈现南高北低、东高西低、由东南向西北递减的趋势;3PPD适用于风险分析中计算致灾因子发生的可能性,因为以该模型为基础的研究结果与近年来辽宁省暴雨发生风险事实一致。 相似文献
993.
土地可持续利用水平是相关指标综合作用的结果,每一个指标都从不同侧面反映了土地资源可持续利用的程度。根据土地利用的特点,借鉴国内外专家确定评价指标体系的经验,选取了自然、环境、社会经济3方面的指标,利用模糊综合评判的方法对湖北省3年的土地利用水平进行了评价。结果显示,虽然湖北省土地持续利用水平较低,但是在1990、1997、2004年呈上升趋势,与实际情况相符,验证了该评价方法的实用性。 相似文献
994.
Zhong Taiyang Huang Xianjin Li Lulu Wang Chen 《中国人口.资源与环境(英文版)》2006,4(1):54-64
In the first, the paper gave a retrospective analysis on the comprehensive assessment of circular economic development. According to the requirement of improving resource & environment efficiency, the paper designed an analytical framework for a comprehensive assessment of regional circular economic growth, which consists of the goal, object and technical line of the comprehensive assessment of regional circular economic development. Given that, the paper discussed the criterion for choosing the assessment index, the approaches of index's weighing determination, the means of data standardization, and the reference system of assessment index value and so on. According to the framework of regional circular economic development evaluation, the paper made a comprehensive evaluation of Jiangsu Province's circular economic development. The result shows that from temporal change, Jiangsu Province's circular economic development had different stages; from the spatial comparison, there is variance among different regions, which could be divided into different types according to the spatial variance and the relation between the development of circular economy and the aggregative index number. There was a remarkable correlation between circular economic development level and GDP or the 2nd industry GDP. Finally, the ?aper gives some suggestions on how to promote the development of drcular economy in Jiangsu Province. 相似文献
995.
996.
四川省固定资产投资现状与对策 总被引:3,自引:0,他引:3
分析了四川省固定资产投资的现状及原因 ,提出了增大投资力度的四条建议 ,并对 2 0 0 0年四川省固定资产投资进行了多方案预测。 相似文献
997.
The paper analyses the periodical characteristics of the economic development of Shandong Province by using the minimum variation analysis model. The analysis shows that the economic development process of Shandong Province has short, medium and long cycles respectively for 6, 12, 19 years, and the fluctuation of the economic development becomes gentler with time passing by. The fluctuation of macro-control policy, investment and consumption are the main reasons of the economic fluctuation. 相似文献
998.
BRANDON P. ANTHONY 《Conservation biology》2008,22(6):1497-1505
Abstract: The importance of biodiversity as natural capital for economic development and sustaining human welfare is well documented. Nevertheless, resource degradation rates and persistent deterioration of human welfare in developing countries is increasingly worrisome. Developing effective monitoring and evaluation schemes and measuring biodiversity loss continue to pose unique challenges, particularly when there is a paucity of historical data. Threat reduction assessment (TRA) has been proposed as a method to measure conservation success and as a proxy measurement of conservation impact, monitoring threats to resources rather than changes to biological parameters themselves. This tool is considered a quick, practical alternative to more cost‐ and time‐intensive approaches, but has inherent weaknesses. I conducted TRAs to evaluate the effectiveness of Kruger National Park (KNP) and Limpopo Province, South Africa, in mitigating threats to biodiversity from 1994 to 2004 in 4 geographical areas. I calculated TRA index values in these TRAs by using the original scoring developed by Margoluis and Salafsky (2001) and a modified scoring system that assigned negative mitigation values to incorporate new or worsening threats. Threats were standardized to allow comparisons across the sites. Modified TRA index values were significantly lower than values derived from the original scoring exercise. Five of the 11 standardized threats were present in all 4 assessment areas, 2 were restricted to KNP, 2 to Limpopo Province, and 2 only to Malamulele municipality. These results indicate, first, the need to integrate negative mitigation values into TRA scoring. By including negative values, investigators will be afforded a more accurate picture of biodiversity threats and of temporal and spatial trends across sites. Where the original TRA scoring was used to measure conservation success, reevaluation of these cases with the modified scoring is recommended. Second, practitioners must carefully consider the need and consequences of generalizing threats into generic categories for comparative assessments. Finally, continued refinement of the methodology and its extension to facilitate the transfer of successful conservation strategies is needed. 相似文献
999.
安徽沿江中心城镇“轴—辐”物流网络构建研究 总被引:7,自引:1,他引:6
21世纪“轴—辐”物流网络作为合理高效的空间系统,已经成为开放型经济体系发展的重要支撑,以安徽沿江地区为案例地进行“轴—辐”物流网络的理性实证研究具有较强的理论价值和实践指导意义。在分析国内外“轴—辐”物流模式研究概况的基础上,诠释了“轴—辐”网络系统规模效益、集聚效益和空间效益等竞争优势及其负面效果。依据现有的资料、实地考察情况,选取了10项指标,运用R型因子分析法对安徽沿江地区41个中心城镇的物流中心性指数进行定量计算、评价,依此遴选合肥、芜湖和安庆三市作为安徽省沿江地区物流中心。最后依据三轴和完全覆盖原则、时间最短原则、多重枢纽配置原则等构建了干线通道和支线通道,形成安徽沿江地区中心城镇“轴—辐”物流网络。 相似文献
1000.
安徽沿江地带投资环境综合研究 总被引:1,自引:0,他引:1
苏勤 《长江流域资源与环境》1997,6(4):302-307
改善投资环境吸引外资是经济发展的重要内容。安徽沿江地带是长江经济带重要的组成部分,对安徽沿江地带投资环境进行了分析与评价,并就进一步完善沿江地带宏观投资环境,推动经济联合发展提出了建议与措施。 相似文献