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1.
近34 a青藏高原年降水变化及其分区   总被引:11,自引:6,他引:11  
 对高原地区34 a(1971—2004年)82站共13 883 d的逐日降水量资料进行了统计,用REOF方法进行了分区,并讨论了趋势变化。青藏高原地区属季风降水区,在东亚季风、印度季风、高原季风和西风带系统的影响下,降水的局部特征显著。近34 a来高原上的降水量整体呈增加趋势,从20世纪70年代到90年代初期降水变化不大,90年代中后期开始明显增加,尤其是近3 a增加明显。青藏高原干旱地区降水完全取决于夏季降水量,并且降水的相对变率大。从青藏高原地区年降水的分区情况来看,西藏及四川的西南部降水增加最明显,每10 a增加幅度为54.5 mm,其次是青海的柴达木盆地和青海湖地区及甘肃的河西走廊地区。而青海的东部及三江源地区,祁连山区,四川的西北部地区呈减少趋势。高原上高海拔地区的降水在减少,而低海拔地区在增加。  相似文献   

2.
黄祖宏  王新贤  张玮 《地理科学》2021,41(6):1088-1095
通过夜光发展指数(NLDI)、文化多样性和城市位序规模法则3个维度进行分析,评估不同时期青藏高原地区的人类发展水平。研究表明:① 21世纪以来,青藏高原地区人类发展水平在逐年提升,但是人类发展水平整体上还处于中等偏下水平,区域内部人类发展水平存在一定的空间差异,东南部夜间灯光强度比较高,人口分布集中;② 青藏高原民族多样性较高区域主要沿着藏彝走廊和河西走廊延伸和扩展,多元文化交融地区的夜间灯光强度高,人类发展水平总体呈上升趋势;③ 采用位序规模法则分析由夜光强度构建的城市规模,最大城市规模太小仍然是青藏高原地区城镇体系的突出问题。  相似文献   

3.
近50 a来黑河流域水资源问题与流域集成管理   总被引:6,自引:1,他引:5  
 基于黑河流域器测水文等资料,分析了近50 a来黑河流域水资源形成区——上游山区水资源变化的历史背景和趋势、平原绿洲-荒漠耗水区3个循环带水资源时空变化及区域耗水特征,以及水资源管理政策变化下的流域中下游水环境问题和社会经济系统水循环过程中的水问题,探讨了解决内陆河流域水问题的水资源集成管理和区域可持续发展对策。  相似文献   

4.
以山洪灾害风险评价的多准则决策模型、最大熵模型、信息量模型三种常见模型为研究对象,选取河西走廊和张掖市为地理区划(大中)、市域(小)空间尺度研究区,构建山洪灾害风险评价指标体系,分别完成基于三种模型的两种空间尺度的山洪灾害风险评价制图,基于甘肃省地质灾害调查与区划报告数据从模型验证、空间自相关、精度对比和尺度效应等角度对比分析三个模型应用于不同空间尺度的适应性,并给出优选模型。结果表明:最大熵模型是河西走廊(地理区划)空间尺度上山洪灾害风险评价的优选模型;多准则决策模型不适用于张掖市(市域)空间尺度评价,且三个模型运行结果均没有河西走廊(地理区划)空间尺度上表现良好;三个模型的尺度效应明显,在地理区划空间尺度上应用较良好,缩小至市域空间尺度上模拟结果误差增大;不同空间尺度上,最大熵模型均优于多准则决策模型和信息量模型,适用于地理区划(大中)、市域(小)空间尺度的山洪灾害风险评价。  相似文献   

5.
Cores of thick leaf spruce from the western Qilian Mountains were subjected to densitometric analysis to obtain data for seven tree-ring parameters (tree-ring width, earlywood width, latewood width, maximum density, minimum density, mean earlywood density and mean latewood density). The chronologies were analyzed individually and then compared with each other. Most of these variables show moderately high values of common variance and mean interseries correlation except latewood and maximum densities. The relationships between the different tree-ring parameters and climate data are also presented. The growth/climate response analyses reveal that the radial growth of thick leaf spruce is the mainly controlled by total annual precipitation (July-June). Herein the residual ring width chronology was used to reconstruct annual (July-June) precipitation of Jiuquan for the period 1768-2009 A.D., and it accounted for 45.0% of the precipitation variance. Multi-taper spectral analysis reveals the existence of significant 11.1-year, 4.9-year, and 2.0- to 3.4-year periods of variability. Spatial analysis shows that the precipitation of Jiuquan has strong common signals for the northern margin of the Tibetan Plateau and Hexi Corridor. Drought events in our reconstruction are compared to the historical archives and other moisture-sensitive tree ring width series in the Hexi Corridor. The results reveal common climatic extremes over much of the Hexi Corridor. Many of these events have had profound impacts on the peoples of the Hexi Corridor over the past several centuries.  相似文献   

6.
河西黑河(弱水)水系的变迁   总被引:4,自引:0,他引:4  
冯绳武 《地理研究》1988,7(1):18-26
中更新世晚期以来黑河流量逐渐减少,由外流河变为内流河,由统一水系变为各自的独立水系,中、下游由地面水和地下水相互转化,不少河道随流量变化及新构造运动影响而改道,从而沿岸新老绿洲互不相连。  相似文献   

7.
水安全评价相关研究已有较多成果,但绝大多数采用P-S-R(压力-状态-响应)及其扩展模型,且评价指标体系的优化校准几乎从未提及.本文将W-SENCE(与水有关的社会-经济-自然复合生态系统)模型引入水生态安全评价领域,从水生态安全的自然属性和社会经济属性方面构建水生态安全评价指标体系,结合模糊系统分析及改进生态位理论对...  相似文献   

8.
论青藏高原范围与面积   总被引:84,自引:4,他引:80  
长期以来 ,种种因素导致学者们对青藏高原确切范围的认识和理解存在差异。根据青藏高原相关领域研究的新成果和多年野外实践 ,从地理学角度 ,充分讨论了确定青藏高原范围和界线的原则与涉及的问题 ,结合信息技术方法对青藏高原范围与界线位置进行了精确的定位和定量分析。得出 :青藏高原在中国境内部分西起帕米尔高原 ,东至横断山脉 ,横跨 31个经度 ,东西长约 2 94 5km ;南自喜马拉雅山脉南缘 ,北迄昆仑山 -祁连山北侧 ,纵贯约 13个纬度 ,南北宽达 15 32km ;范围为 2 6°0 0′12″N~ 39°4 6′5 0″N ,73°18′5 2″E~ 10 4°4 6′5 9″E ,面积为 2 5 72 4× 10 3km2 ,占我国陆地总面积的 2 6 8%。  相似文献   

9.
The architectural parameters of Reaumuria soongorica root system in different habitats of Gansu Province, China were analyzed to examine its ecological adaptability to arid environments. Results show that: (1) Topological indices of R. Soongorica root sys- tem are small in all habitats, and root branching pattem tends to be dichotomous. Also, the indices gradually increase in the Min- qin windblown sand region and the Zhangye Gobi region in Hexi Corridor, which indicates that drought tends to produce her- ringbone-like root branching pattems. (2) Fractal dimension values ofR. Soongorica root system are small and not obvious in the Minqin windblown sand region and the Zhangye Gobi region in Hexi Corridor, with values of 1.1778 and 1.1169, respectively. Fractal dimension values are relatively large in Jiuzhoutai semi-arid hilly and gully region of the Loess Plateau, which indicates that the R. Soongorica root system has better fractal characteristics in this region than in the other regions. (3) Total branching ra- tios of the R. Soongorica root system in arid regions of Hexi Corridor are smaller than that in the Jiuzhoutai semi-arid hilly and gully region of the Loess Plateau. This shows that root branching ability in the semi-arid region is stronger, and it decreases to some degree with increased drought. (4) The root connection lengths of R. soongorica root system are long in all habitats, but there are significant length differences between the different habitats. The root connection length at the Minqin windblown sand region is the longest. It is concluded that R. soongoriea adapts to arid environments by decreasing root branching, decreasing root overlap and increasing root connection length, which makes its root branching pattern tend to be herringbone-like to reduce com- petition in root internal environment for nutrients and to enhance root absorption rate of nutrients, and ensure effective nutrition space. Thus the roots can absorb enough water and nutrients in resource-poor settings to ensure normal physiological requirements.  相似文献   

10.
河西走廊:绿洲支撑着城市化!——与仲伟志先生商榷   总被引:18,自引:5,他引:13  
方创琳 《中国沙漠》2003,23(3):334-336
针对仲伟志先生在《经济观察报》(2002年10月14日)撰写的《河西走廊:城市化覆盖绿洲?》一文的若干观点,提出了自己近年来研究河西走廊得出的基本看法。作者认为,在河西走廊,有绿洲就有城市,有城市就有城市化;城市化不会覆盖绿洲,城市化会推动绿洲更加走向繁荣;水源绝不是城市化的最大瓶颈,城市化更不会制造沙漠;在保护绿洲生态环境的同时,加快走廊城市化发展进程,这是河西走廊生态环境改善和人民生活水平提高的有效途径。绿洲支撑着城市化,合力共筑着河西走廊作为中国西部生态经济走廊的开发与发展。  相似文献   

11.
草地是干旱、半干旱区面积占优势的生态系统,在时间尺度上对其进行生态系统服务价值评估是判断区域生态系统处于改善或退化的主要途径。基于野外调查和遥感分类解译划分的河西走廊荒漠化草地基础数据,首次建立了河西走廊不同类型、不同程度荒漠化草地生态系统服务价值计算和修正方案,评估了第三次(2004年)、第四次(2009年)和第五次(2014年)荒漠化监测期河西走廊荒漠化草地生态系统服务价值动态变化及服务价值结构。结果表明:(1)2004—2014年间河西走廊草地荒漠化呈现轻微逆转趋势,荒漠化草地面积由519.7万 hm2减少至357.7万 hm2;(2)10年间河西走廊荒漠化草地生态系统服务总价值以损失为主,损失量达209亿元;(3)河西走廊荒漠化草地生态系统服务总价值在时空分布、荒漠化类型和程度方面存在显著差异;(4)河西走廊荒漠化草地生态系统服务倾向于气候调节、净化环境和水文调节功能。  相似文献   

12.
In this paper, a variation series of snow cover and seasonal freeze-thaw layer from 1965 to 2004 on the Tibetan Plateau has been established by using the observation data from meteorological stations. The sliding T-test, M-K test and B-G algorithm are used to verify abrupt changes of snow cover and seasonal freeze-thaw layer in the Tibetan plateau. The results show that the snow cover has not undergone an abrupt change, but the seasonal freeze-thaw layer obviously witnessed a rapid degradation in 1987, with the frozen soil depth being reduced by about 15 cm. It is also found that when there is less snow in the plateau region, precipitation in South China and Southwest China increases. But when the frozen soil is deep, precipitation in most of China apparently decreases. Both snow cover and seasonal freeze-thaw layer on the plateau can be used to predict the summer precipitation in China. However, if the impacts of snow cover and seasonal freeze-thaw layer are used at the same time, the predictability of summer precipitation can be significantly improved. The significant correlation zone of snow is located in middle reaches of the Yangtze River covering the Hexi Corridor and northeastern Inner Mongolia, and the seasonal freeze-thaw layer exists in Mt. Nanling, northern Shannxi and northwestern part of North China. The significant correlation zone of simultaneous impacts of snow cover and seasonal freeze-thaw layer is larger than that of either snow cover or seasonal freeze-thaw layer. There are three significant correlation zones extending from north to south: the north zone spreads from Mt. Daxinganling to the Hexi Corridor, crossing northern Mt. Taihang and northern Shannxi; the central zone covers middle and lower reaches of the Yangtze River; and the south zone extends from Mt. Wuyi to Yunnan and Guizhou Plateau through Mt. Nanling.  相似文献   

13.
张戬  陈佳  黄馨  王子侨 《中国沙漠》2019,39(1):203-211
城市经济脆弱性作为当前脆弱性研究中的重要领域,为人-地系统耦合研究提供了新的视角,并为城市可持续健康发展提供有益的决策支持和管理方法。依据城市经济脆弱性内涵,基于暴露度、敏感性、适应能力构建了城市经济脆弱性评价指标体系,运用熵权TOPSIS法评价河西走廊地区及区域内五市的城市经济脆弱性,并采用障碍度模型识别影响区域城市经济脆弱性变化的因素。结果显示:(1)2006—2015年,河西走廊地区城市经济脆弱性呈现出先曲折下降(2006—2011年)再波动上升趋势(2012—2015年);(2)河西走廊地区的城市经济脆弱性具有明显的空间特征,经历了东西高、中部低到整体较高的演变过程;(3)阻碍河西走廊地区城市经济脆弱性降低的障碍因子由适应能力逐步转变为暴露度。针对河西走廊地区各市主要障碍因子,提出针对性优化措施。  相似文献   

14.
以甘肃河西地区为研究区,采用耦合协调度模型和农业水土资源匹配系数法分别对河西五市和河西走廊三大内陆河中游地区水土耦合协调情况进行量化研究,并以此为基础通过灰色关联度法分析水土资源耦合协调度影响因素.结果表明:(1)2000-2019年,河西五市水土资源耦合协调度整体提升了 64.65%,由濒临失调转换为初级协调,呈现不...  相似文献   

15.
基于扎根理论研究产业园区集群化发展现状与存在问题。研究发现,园区集群化发展需要园区企业有效利用其显性契约、强化关系契约,提升联合规划、联合解决问题的能力;提升河西走廊产业园区集群化发展水平要运用组织生态学中的内外因视角发现问题,使外因为内因变化提供更好的环境;依照产业园区集群化发展模型,增强企业根植性、创新性和开放性,强化园区企业契约关系,推动集群向创新集群发展。  相似文献   

16.
Water has become a key restricting factor of the urbanization process in developing arid areas. Based on qualitative and quantitative methods, we constructed an integrated indicator system to assess the status of water resources and urbanization system in arid area, and established an AHP model reformed by entropy technology to evaluate the temporal and spatial variations of water resources constraint intensity on urbanization. This model is applied to the Hexi Corridor, a typical arid area in NW China. Results show that, water resources constraint intensity on urbanization in the Hexi Corridor is bigger in the east and smaller in the west. It has changed from the less strong constraint type into the strong constraint type from 1985 to 2005, yet it decreased appreciably in recent years. At present, most areas in the Hexi Corridor belong to the less strong or strong constraint type. Through rational adjustment of water resources and urbanization system, the Hexi Corridor can still promote water resources sustainable utilization and accelerate the urbanization process. This study suggests that the integrated assessment model of water resources constraint intensity on urbanization is an effective method to analyze the conflicts between water resources and urbanization system in arid area.  相似文献   

17.
干旱区水资源对城市化约束强度的时空变化分析   总被引:16,自引:0,他引:16  
鲍超  方创琳 《地理学报》2008,63(11):1140-1150
水资源对城市化的约束力已经成为干旱缺水地区决定城市化发展速度, 进而决定城市化和社会经济发展规模的重要外营力之一, 科学度量并探讨其时空变化, 对水资源可持续利用与城市化正常推进具有重要意义。以定性与定量分析相结合的方法建立了水资源对城市化 约束强度的综合测度指标体系, 采用熵技术支持下的层次分析法构建出水资源对城市化约束强度的综合测度模型, 并对1985-2005 年河西走廊水资源对城市化约束强度的时空变化进行了分析。结果表明, 河西走廊水资源对城市化的约束强度在空间上总体表现为自东向西逐渐减小, 在时间上表现为由较强约束类型变为强约束类型, 总体呈不断增加态势, 但近年来略有缓解。虽然河西走廊水资源开发利用潜力综合指数与城市化系统综合发展指数都较低, 面临缺水和发展的双重矛盾, 但目前河西走廊大部分地区水资源对城市化的约束强度仍属于较强或强约束类型, 仍然能够通过合理调控实现可持续发展。  相似文献   

18.
干旱区水资源对城市化约束强度的综合评价模型   总被引:7,自引:3,他引:4  
Water has become a key restricting factor of the urbanization process in developing arid areas. Based on qualitative and quantitative methods, we constructed an integrated indicator system to assess the status of water resources and urbanization system in arid area, and established an AHP model reformed by entropy technology to evaluate the temporal and spatial variations of water resources constraint intensity on urbanization. This model is applied to the Hexi Corridor, a typical arid area in NW China. Results show that, water resources constraint intensity on urbanization in the Hexi Corridor is bigger in the east and smaller in the west. It has changed from the less strong constraint type into the strong constraint type from 1985 to 2005, yet it decreased appreciably in recent years. At present, most areas in the Hexi Corridor belong to the less strong or strong constraint type. Through rational adjustment of water resources and urbanization system, the Hexi Corridor can still promote water resources sustainable utilization and accelerate the urbanization process. This study suggests that the integrated assessment model of water resources constraint intensity on urbanization is an effective method to analyze the conflicts between water resources and urbanization system in arid area. Foundation: Knowledge Innovation Project of the Chinese Academy of Sciences, No.KZCX2-YW-307-02; China Postdoctoral Science Foundation; K. C. Wong Education Foundation, Hong Kong Author: Bao Chao (1978–), Ph.D, specialized in urbanization and water sustainable utilization.  相似文献   

19.
Modern dust storms in China: an overview   总被引:4,自引:0,他引:4  
This paper discusses the sources, spatial distribution, frequency and trend of dust storms in China. Most dust storms in China originate from one of three geographic areas: the Hexi (River West) Corridor and western Inner Mongolia Plateau, the Taklimakan Desert, and the central Inner Mongolia Plateau. Dust is most likely from deteriorated grasslands, Gobi, alluvial, lacustrine sediments and wadis at the outer edge of deserts. But deserts themselves contribute only slightly to the dust storm directly. Two geographic areas frequently have dust storms: one is in the western Tarim Basin, a ground surface of deteriorated land and wadi, but it only affects its neighboring areas, and the other one is in the western Inner Mongolia Plateau, a ground surface of Gobi, alluvial and lacustrine sediments, but it causes most of the dust storms in north China. Generally speaking, dust storms have reduced in most regions of China from the 1950 to 2000. Dust storms are highly correlated with human activities and climate changes.  相似文献   

20.
为了对中国\!三北\"防护林工程重点建设区河西走廊的防风固沙林工程建设成效进行客观评估,选取4期Landsat MSS、TM/ETM数据,在GIS技术支持下对1978-2007年期间面状林地的动态进行遥感监测。监测结果表明,整个研究区林地面积呈先下降后上升趋势,表现为1978-1990年林地面积明显减少,1990-2000年林地面积大幅度上升,2000-2007年林地呈缓慢上升状态;在不同空间范围内,山区各县林地变化较为缓和,平原区各县林地变化较为明显。在此基础上,分析不同林地变化特征,得出人为因素是本地区林地变化的主要原因。  相似文献   

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