干旱内陆河流域人居环境适宜性评价——以石羊河流域为例(英文)   总被引：6，自引：2，他引：4  

魏伟  石培基  周俊菊  冯海春  王旭峰  王雪平 《地理学报(英文版)》2013,23(2):331-343

The study employs slope,aspect,relief degree of land surface,land use,vegetation index,hydrology and climate,as evaluation indexes to set up the Human Settlements Environmental Index(HEI) model to evaluate the environmental suitability for human settlements in the Shiyang River Basin.By using GIS spatial analysis technology,such as spatial overlay analysis,buffer analysis and density analysis,the environmental suitability of the human settlement spatial situation and spatial pattern are established to analyze their spatial distribution.The results show that the index of suitability for human settlements in the Shiyang River Basin is between 17.13 and 84.32.In general,suitability for human settlements decreases from the southwest to the northeast.Seen from an area pattern,the suitable region is mainly distributed in the Minqin oasis,Wuwei oasis and Changning basin,which are about 1080.01 km 2 and account for 2.59% of the total area.Rather and comparatively suitable region is mainly distributed around the counties of Gulang,Yongchang and north of Tianzhu,which is about 1100.30 km 2.The common suitable region is mainly distributed outside the counties of Yongchang,Jinchuan and most parts of Minqin County,which are about 23328.04 km 2,accounting for 56.08% of the total area.The unsuitable region is mainly distributed upstream and to the north of the river,which is about 9937.60 km 2,accounting for 23.89% of the total area.Meanwhile,the least suitable region is distributed around the Qilian Mountains,which are covered by snow and cold desert and lie in the intersecting area between the Tengger Desert and Badain Jaran Desert.The total area is about 6154.05 km 2,accounting for 14.79% of the total area.Suitable regions for human habitation are mainly distributed around rivers in the form of ribbons and batches,while others are scattered.The distribution pattern is identical to the residential spatial pattern.In addition,the relationships between HEI and other factors have been analyzed.There is a clear logarithmic correlation between the residential environment and population,that is,the correlation coefficient between the evaluation value and population density reaches 0.851.There is also a positive correlation between the residential environment and economy,which reaches an evaluation value of 0.845 between the residential environment and GDP.Results also show that the environment is out of bearing with the existing population in Shiyang River Basin.Spatial distribution of population is profoundly affected by severe environmental problems,such as the expanded deserts,the hilly terrain and the changing climate.Surface water shortage and slow economic growth are bottlenecks for suitable human settlement in the Shiyang River Basin.Combining these problems with planning for construction of new country and the exploitation of local land,some residential areas should be relocated to improve the residential environment.  相似文献   

2021年夏季我国气候异常特征及成因分析     

赵俊虎  陈丽娟  章大全 《气象》2022,48(1):107-121

2021年夏季我国天气气候异常特征突出,极端天气气候事件多,东部主要多雨区在我国北方,降水的季节内变化显著,华南前汛期开始偏晚、江淮流域梅雨和华北雨季开始偏早.东亚大气环流季节内变化对降水异常的空间分布影响较大.6月,东北冷涡活动频繁,导致东北及邻近区域降水异常偏多,黑龙江、嫩江流域发生严重汛情;东北冷涡的异常活跃可能...  相似文献   

淮河流域洪汝河段浅层地下水质量评价方法浅析     

刘海风  邓斌  杨小双 《地下水》2012,(1):20-22

依据2008年度淮河流域洪汝段(河南省域)536组浅层地下水水质化验资料,选取49个评价指标,分别采用内梅罗指数法和模糊数学法进行地下水质量评价,对两种方法的评价结果进行对比浅析,阐述二者的适用条件。结果表明:模糊数学法更好地揭示了水质等级划分上的模糊性,能均衡反映各指标的综合影响,评价结果更符合实际情况,更适用于评价指标较多的水质评价。  相似文献   

广东徐闻地下水供水水质评价     

王双 《地下水》2012,34(6):73-74,139

地下水资源勘查评价项目是"粤北岩溶石山地区和雷州半岛地区地下水资源勘查监测项目"的重要组成部分。根据采回水样的分析结果,对本区地下水供水水质分别采用单项指标评价法和内梅罗综合指数法进行评价,结果得出,浅、中、深地下水局部不同程度遭到污染,要采取有效措施杜绝水源继续遭受污染和预防污染扩散,确保地下水供水安全。  相似文献   

老挝万象沙拉康铁矿地质及成因     

常鸿 《云南地质》2012,31(4):504-507

矿体赋存于中二叠统中上部凝灰岩中。17号饼状铁异常面积大,峰值最高。V1矿体南、北控制545米。V2矿体南西、北东走向控制370米。次级构造发育,厚度大、品位富,为低硫、低磷炼铁用褐铁矿矿石。  相似文献   

灌注桩结合三轴止水及内支撑的基坑围护设计     

姚萍  赵升峰  章新 《岩土工程技术》2012,26(4):173-176,180

深基坑是一项理论复杂,学科综合性较高及风险较大的工程。工程中经常出现支撑体系失稳、围护结构失稳、坑壁漏水、坑底隆起等现象。以上海某深基坑工程为对象,分析了深基坑围护方案的选型要点,总结了深基坑围护设计中关键的计算与验算内容。最后对比分析了设计计算结果与实际监测数据结果,证明了所采取的围护形式的有效性,希望能为今后类似工程提供一些借鉴和参考。  相似文献   

内波、内潮汐沉积形成过程中内波传播方向与沉积物搬运方向相反的定量解释   总被引：1，自引：0，他引：1       下载免费PDF全文

李琳静 《沉积与特提斯地质》2012,32(2):44-48

本文从海洋物理学角度出发,以内波波动理论为基础,通过建立两个不同密度的水层界面上的两层模型的波动方程对内波的传播特征进行定量解释。通过定量解释表达式可知：内波在两个不同密度的水层界面上传播时,两层内波流之水平速度方向相反,保持通过海底的整个截面的流通量为零。在密度界面之下,波谷处内波流的运动方向与内波前进方向相反,由于波谷相对于波峰更接近于海底,即波谷处截面积较小,故波谷下方的流速较波峰下方的流速大,容易形成与内波前进方向相反的单向优势流动,这种单向优势流动搬运沉积物的总趋势与内波的前进方向相反。  相似文献   

香格里拉小中甸冈达概组下段岩石化学特征及构造背景分析     

吕劲松  肖渊甫  邓江红  王涛  程超杰  龚婷婷  于海军  邓元兵 《地质与勘探》2012,48(6):1214-1220

香格里拉小中甸冈达概组下段(Pg1)分布于金沙江构造带与义敦岛弧之间的中咱微陆块,属中甸基性火山岩带。本文研究中咱微陆块南部冈达概组下段,该地层主要由玄武质角砾凝灰熔岩、微晶玄武岩和玄武质角砾凝灰岩混层组成,具有富碱、高钛、轻稀土强烈富集的特征,是地幔低度熔融的产物,属大陆板内张裂型火山岩,与东邻区的峨眉山玄武岩(Pe)有相似的地球化学特征,反映两者的地幔源区具有亲缘关系,与地幔柱活动有关。  相似文献   

内出进洞方式对浅埋偏压隧道洞口段围岩稳定性影响研究          下载免费PDF全文

杨超  张永兴  黄达  娄勇 《水文地质工程地质》2012,39(4):49-54

厦蓉线水都高速平寨隧道左洞洞口受施工条件、浅埋和偏压等因素的影响,采取了中横洞内出的进洞方法。现场监测成果表明施工取得了良好的效果。为研究该进洞方式对洞口浅埋偏压段围岩稳定性的影响,利用FLAC3D程序对平寨隧道施工过程进行三维仿真分析,比较中横洞内出和正面开挖两种进洞方式下左洞洞口围岩变形和应力变化情况,结果表明中横洞内出方案对近洞口约24m范围内围岩影响较小,为较优方案。  相似文献   

Early Cretaceous Paleomagnetic Results of the Simao Area in the Indochina Block and Its Tectonic Implications     

ZHANG Haifeng  TONG Yabo  WANG Heng  YANG Zhenyu 《地质学报》2012,86(6)

对印支地块思茅地区的早白垩世红层开展详细的岩石磁学和古地磁学研究,获得镇沅剖面特征剩磁方向Ds=52.4°,Is=45.5°,κ=77.9,α95=6.3°;普洱剖面特征剩磁方向Ds=46.2°,Is=46.6°,κ=50.9,α95=5.6°;江城剖面特征剩磁方向Ds=8,6°,Is=42.2°,κ=117.1,α95 =4.0°.对普洱和江城剖面进行E-I磁倾角偏低检验,结果显示江城剖面不存在磁倾角偏低,普洱剖面由于偏角较分散,导致其伸展方向出现假象,推测的磁倾角偏大,出现实测磁倾角偏低的假象.思茅地区各采样剖面之间的磁偏角差异表明,块体内部发生过差异性旋转变形,其变形的过程不仅受控于边界深大断裂,也与内部小断裂的活动有密切关系.若进一步考虑华南地块白垩纪可能存在的磁倾角偏低现象,则该结果说明印度支那地块思茅地区白垩纪以来相对于华南地块向南滑移量为570±310km,接近构造地质研究推测的红河大断裂左行滑移最.  相似文献