水平分辨率对DEM流域特征提取的影响   总被引：7，自引：0，他引：7  

易卫华  张建明  匡永生  米丽娜 《地理与地理信息科学》2007,23(2):34-38

选取石质山地与黄土丘陵过渡区宛川河流域作为研究区,利用1∶5万、水平分辨率10~100 m栅格DEM提取流域特征参数进行分析。结果表明:DEM水平分辨率对数字河网的提取精度有影响,提取的流域面积差别很小,河流长度、河道总长、河道坡度以及河网密度有偏差,流域平均坡度变化明显,长度和坡度特征参数的变化导致流域汇流时间及滞时不一致。  相似文献   

Application of <Superscript>137</Superscript>Cs fingerprinting technique to interpreting sediment production records from reservoir deposits in a small catchment of the Hilly Loess Plateau,China   总被引：1，自引：0，他引：1  

Zhang XinBao  Wen ZhongMing  Feng MingYi  Yang QinKe  Zheng JinJun 《中国科学D辑(英文版)》2007,50(2):254-260

According to variations of 137Cs and clay contents, 44 flood couplets were identified in a profile of reservoir deposit with a vertical length of 28.12 m in the Yuntaishan Gully. Couplet 27 at the middle of the profile had the highest average 137Cs content of 12.65 Bq kg-1, which indicated the 1963s' deposits, then 137Cs content decreased both downward and upward in the profile. The second top and bottom couplets had average 137Cs contents of 2.15 Bq kg-1 and 0.92 Bq kg-1, respectively. By integrated analysis of reservoir construction and management history, variations of 137Cs contents over the profile, sediment yields of flood couplets and rainfall data during the period of 1958-1970, individual storms related to the flood couplets were identified. 44 floods with a total sediment yield of 2.36×104 m3 occurred and flood events in a year varied between 1 and 10 times during the period of 1960-1970. 7-10 flood events occurred during the wet period of 1961-1964 with very wet autumn, while only 1-2 events during the dry period of 1965-1969. Average annual specific sediment yield was 1.29×104 t km-2 a-1 for the Yuntaishan Gully during the period of 1960-1970, which was slightly higher than 1.11 ×104 t km-2 a-1 for the Upper Yanhe River Basin above the Ganguyi Hydrological Station and slightly lower than 1.40 ×104 t km-2 a-1 for the nearby Zhifang Gully during the same period. Annual specific sediment yields for the Yuntaishan Gully were correlated to the wet season's rainfalls well.  相似文献   

桩基动力检测技术的现状及存在的问题   总被引：3，自引：0，他引：3  

曹宇春  吴世明  高广远 《上海国土资源》2002,86(1):43-45,60

文章通过对桩基动力检测方法应用现状的简要回顾，分析了桩基高应变和低应变动测的特点和局限性。在此基础上，提出了在桩基检测和测试结果分析中注意的问题。  相似文献   

黑河干流山区流域月蒸发力计算模型   总被引：10，自引：0，他引：10  

陈仁升  康尔泗  杨建平  王书功 《水文》2002,22(6):5-10

研究西北内陆河山区流域的水文循环,对于维持区域可持续发展和生态环境的保护具有重要意义。应用数值迭代方法,对黑河山区流域平均月蒸发力与月平均气温和月降水量的关系进行了探讨。结果表明,山区平均月降水量、月平均气温和月蒸发力之间存在着复杂的非线性关系,降水和气温都是影响蒸发力的一个综合因子。  相似文献   

数字高程模型在流域水文模型应用中的若干问题   总被引：8，自引：1，他引：8  

孔凡哲  芮孝芳 《水文》2002,22(5):1-4

数字高程模型(DEM)在流域水文模型中得到了广泛应用,主要是因为DEM能够自动提取流域水文模型所需要的确定流域排水结构的水文信息。回顾并讨论了DEM在流域水文模型应用中的几个问题,主要包括河网自动提取的方法、DEM中排水方向的确定以及封闭洼地的处理,同时还包括在流域水文模型中应用时DEM的结构类型及尺度问题。由于由DEM生成的模拟河网与流域实际河网间存在一定的差别,最后还讨论了如何对模拟河网进行矫正的问题。  相似文献   

航天遥感立体测绘小卫星目标跟踪与角度测量     

李世忠  王仁礼 《测绘学院学报》2001,18(1):29-32

随着现代小卫星技术的不断发展成熟，利用该技术为地球观测服务将成为一件远景可观，意义深元的事情，文中针对舆型航天遥感立体测绘微小卫星的需求，结合单脉冲测角原理给出了航天遥感测绘小卫星地面站面线系统的整体分析与设计。  相似文献   

黄土丘陵沟壑区作物生产潜力影响因素分析——以王家沟流域为例   总被引：2，自引：0，他引：2  

李忠武  蔡强国  唐政洪  吴淑安  朱远达 《地理研究》2001,(5)

针对黄土丘陵沟壑区土壤侵蚀非常严重、作物产量低而不稳以及农业生产力水平低下的特点 ,本文首先分析了近几年来王家沟流域不同种类和不同年份作物生产力变化的特征 ,然后在地理信息系统 (GIS)技术支持下 ,利用基于土壤侵蚀条件下的YIELD作物生产力模型并结合各作物的实际观测资料 ,从降雨量、气温等气象因素以及地膜覆盖、施肥、梯田等耕作措施两方面分析了该小流域作物生产力变化的原因 ,结果表明在气象因素 (大气降水 )和土壤侵蚀的共同影响下 ,土壤水分和养分的变化是影响该区域作物生产力变化的主要制约因素。  相似文献   

黄土丘陵沟壑区小流域降雨入渗产流点面转化   总被引：7，自引：6，他引：7  

袁建平  蒋定生 《地理科学》2001,21(3):262-266

在充分考虑小流域土壤入渗速率点面转化及地表结皮等影响因素在内的基础上 ,提出了小流域土壤入渗速率点面转化公式 :fm=fn×Sn/S×an×bn。以纸坊沟小流域为例 ,将实测的流域土壤入渗速率值 (点渗值 )利用上式进行转化 (面渗值 ) ,并与流域径流出口观测站由降雨径流观测值根据水量平衡原理推算出的面渗值进行对比 ,平均相对误差仅为 2 .42 %。初步得出流域土壤面渗率与不同治理度、年内 5～ 9月降雨总量间的单因子和复合因子高精度回归方程 ,为流域综合治理后的水资源量变化趋势提供一条量化途径  相似文献   

Conceptualising State‐Controlled Resort Islands for an Environment‐Friendly Development of Tourism: The Maldivian Experience     

Manfred Domroes 《Singapore journal of tropical geography》2001,22(2):122-137

The Maldives host a sophisticated and competitive international tourist industry which has replaced fishing as the dominant economic activity. With their rich tropical reef ecosystems and the abundant biodiversity of their marine environment, a total of 86 uninhabited islands had been converted into Resort Islands by the end of 2000. Resort Islands are equipped with comprehensive facilities for accommodation, food, recreation and leisure. They are also strictly reserved for foreign tourists and guarantee complete privacy. This gives the benefit of averting conflicts of acculturation with local islanders. In the arena of impacts on the physical environment, however, the consumptive leisure lifestyle of the tourists has been harmful to the Resort Islands as seen in sewage, garbage and waste pollution, as well as reef destruction and beach erosion. While the government of the Maldives takes great effort to harmonise tourism and the environment, the growth of mass tourism in the last 20 years has engendered grave environmental impacts. For future sustainable development of the Resort Islands, the tourists' environmental awareness must be increased to promote greater responsibility for the protection of the fragile coral and reef ecosystems of the Maldives.  相似文献   

金属矿地震散射波场的数值模拟研究   总被引：7，自引：0，他引：7  

孙明  林君 《地质与勘探》2001,37(4):68-70

地震方法用于寻找石油、煤田等沉积层控矿床已取得许多成功经验和大量的成果；对于金属矿可依据微扰理论，通过地震波散射响应的强弱推断矿体。模拟实验结果表明，散射波相干性的好坏与杂乱散射体的不均匀性有关；不均匀性越强，产生的散射相干性就越好。  相似文献