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关于中国西北干旱区陆—气相互作用及其对气候影响研究的最近进展 总被引:7,自引:6,他引:7
本文综述了中国西北干旱区陆—气相互作用及其对气候影响研究的最近进展。文中不仅回顾了“中国西北干旱区陆—气相互作用观测试验”经过连续12年的观测和多次加强期观测所取得的干旱区陆面过程参数的分析以及边界层和陆—气相互作用特征等的分析和研究,而且综述了应用这些参数来优化有关陆面过程模式的参数化方案和改进有关陆面过程模式的研究;并且,本文还综述了关于中国西北干旱区感热输送特征以及西北干旱区陆—气相互作用对中国东部气候的影响及其机理,并揭示了中国西北干旱区春、夏季具有高感热输送特征,此高感热对中国东部夏季气候变异有重要影响。此外,本文还指出今后在此方面应进一步观测和深入研究的科学问题。 相似文献
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深基坑施工周边管线变形监测分析和处理 总被引:2,自引:1,他引:2
在基坑开挖过程中,由于应力环境改变,造成附近管线位移较大。该工程进行了系统监测,根据监测数据对周边管线的变形进行较系统的分析和变形处理。 相似文献
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随着近几十年河北省经济社会的快速发展、人口增长和城镇化水平的不断提高,产生了大量崩塌、滑坡、泥石流、地面塌陷、地裂缝、地面沉降等地质灾害,影响了河北省经济社会又好又快发展。产生这些地质灾害的主要原因就是人类活动强度超出了当地的地质环境承载能力。为客观分析河北省地质环境承载能力,建立了河北省地质环境承载能力评价指标,并分别进行了河北省地质环境承载能力本底和状态评价。通过对评价结果的研究分析,提出了新的地质环境承载能力状态评价指标和方法,为将来建立多方协同的资源环境承载能力监测预警长效机制提供了参考。 相似文献
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ZHUANG Hanping LU Jialan FU Jiamo LIU Jinzhong Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou REN Chigang ZOU Degang The nd Department of Physics Fudan University Shanghai TIAN Weizhi Chinese Academy of Atomic Science Beijing 《《地质学报》英文版》1998,72(3):299-307
By means of kerogen purification, the proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA), the authors have studied the organic/inorganic occurrence modes of the metallic elements of the Baiguoyuan silver-vanadium deposit hosted in black shale in Hubei Province, China. The result shows that Au, Hg and Ta have a strong tendency to occur organically, with more than 70% of these elements being associated organically. Se, Ga, Ag and Hf are partly associated with organic matter, with more than 20% of them occurring organically. Compared with the above elements, Zn, Cu, As and Sb are weakly associated organically, and tend to be enriched in kerogen. However, Mn, Th, U, V, Co, Cr, Al, Fe and Sc usually occur inorganically. Of the rare earth elements (REE), La, Ce, Tb, Dy, Yb and Lu have stronger ability to be associated with organic matter than Sm and Eu. 相似文献
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为了探讨台湾相思群落生长发育与气候特征的关系,选用11个位于大屿靠海一侧不同地点的台湾相思群落研究对象。通过2016年4—12月对台湾相思标记枝条的生长状况进行长期监测。观测结果表明:11个样点受盐害叶片占比为1.16%~51.48%,受虫害叶片占比为30.27%~59.78%。植株大多受到盐害与虫害的干扰,花数量和花蕾数量处于一个较低的水平。由植物生长状况与气候特征的相关性结果可知,风向和风力随月份变化而变化,12月风力最高达5.93m/s。月份和风向与受盐害叶片占比、受虫害叶片占比均呈现极显著相关性。在开展海岛植被生态修复时,需要注重冬季养护、病虫害防治和筛选抗风、耐盐雾的海岛适生物种。 相似文献
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流域生态补偿研究现状及关键问题剖析 总被引:3,自引:0,他引:3
在流域,因竞争性用水导致上下游之间、人类发展与生态环境之间的矛盾日益尖锐,急需建立健全流域生态补偿机制.通过对国内外流域生态补偿研究进展进行梳理,发现流域生态补偿研究主要集中在流域尺度的补偿计划实施评价、补偿尺度的选择、补偿标准的测算、生态补偿与减少贫困关系、流域生态补偿的空间差异性等方面,其关键问题在于生态补偿主体和对象的确定以及补偿标准的制定;研究认为通过流域断面水量水质及相关利益分析方法来确定补偿主体和对象;而补偿标准则以流域上下游生态损益、机会成本、居民支付意愿分别作为补偿上限、参考值和下限来综合确定.以此为基础,构建流域多种生态要素、多元主体间的流域生态补偿机制研究框架.最后,就流域生态补偿机制构建过程中有待解决的科学问题进行了讨论. 相似文献
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Degang Zhou Rafael Eigenmann Wolfgang Babel Thomas Foken Yaoming Ma 《Theoretical and Applied Climatology》2011,105(1-2):217-228
This study investigates the near-ground free convection conditions (FCCs) based on eddy covariance (EC) measurements at Nam Co station near the Nam Co Lake on the Tibetan Plateau (TP). The spatial and temporal structure of EC measurements at this station is evaluated by using the comprehensive software package TK2 together with a footprint model. The obtained high-quality turbulent flux data are used to study the occurrence of FCCs, which can be detected with the EC system by calculating the stability parameter. Two types of generation of FCCs can be identified. (1) During the wind direction change of a diurnal thermally forced land-lake circulation system in the morning, strongly reduced wind speeds and simultaneously high buoyancy fluxes lead to a period of dominance of buoyancy over shear, and hence, to the occurrence of FCCs. (2) On days with the appearance of clouds, the land-lake circulation is weakened or reversed, dependent on the temperature gradients between the land and the Nam Co Lake. During the period of adaptation of the land-lake breeze to the alternating situation of heating differences, wind speeds decrease and buoyancy again dominates over shear near the ground. These are the situations where FCCs are also detected during the entire day at Nam Co station. The investigation of FCCs regarding the whole measurement period shows that FCCs can be mainly attributed to case (1) during the non-monsoon period, while FCCs are generated by both mechanisms (1 and 2) during the monsoon season. An impact of the FCCs on the near-ground profiles of air temperature and humidity is demonstrated. The FCCs are assumed to play an important role for the land surface-atmosphere exchange processes and the atmospheric boundary layer (ABL) conditions on the TP by providing an effective transport mechanism of near-ground air mass characteristics into upper parts of the ABL. 相似文献
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蓝色海湾整治行动是我国海洋生态文明建设的重大举措之一,通过实施海岸带生态修复、滨海湿地生态修复、海岛海域生态修复,使海洋生态环境质量得以改善,海域、海岸带和海岛生态服务功能得到有效提升。为了客观评价蓝色海湾整治行动的修复效果,文章借鉴我国海洋整治修复项目实践情况,围绕“水清、岸绿、滩净、湾美、物丰”的美丽海洋建设目标,构建了涵盖16个指标的蓝色海湾指数评估体系,从生态环境保护修复和人居环境改善等角度科学反映蓝色海湾整治行动的生态、社会、经济效益,并以第一批温州市蓝色海湾整治行动为例,实施蓝色海湾指数评价。蓝色海湾指数评估体系的构建对于全面掌握全国蓝色海湾整治行动的实施情况,科学指导修复工程的有序实施具有非常重要的意义,能够为我国开展海洋生态修复提供理论支撑。 相似文献