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Spatial distribution of wind erosion and its driving factors in China

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Journal of geographical sciences 2001年第2期11卷 127-139页

作者： ZHANG Guo-ping~1, ZHANG Zeng-xiang~1, LIU Ji-yuan~2.(1. institute of Remote Sensing Application, cas,{2., China 2. institute of geographic sciences and natural resources research, cas,{2., China) institute of Remote Sensing Application CAS institute of geographic {2. and natural resources research CAS

Based on remote sensing and geographic information system, the spatial distribution of nation-wide wind erosion is studied, and the 1∶100 000 national map of soil erosion by wind in China is made. Wind speed, soil dryness,NDVI, soil texture and the slope of land surface are the key factors to wind erosion. The relations between wind erosion and each factor are discussed. The method of principal component is used to pick up the information included in the five factors, and the wind erosion dynamic index (WEDI) is established. Its comparison with theRS/GIS derived data shows thatWEDI can reflect the potential capacity of soil erosion by wind. The dynamic process of the wind erosion is studied to reveal the distribution of the most intense wind erosion regions and the dominant factors in these regions. All these studies may greatly help the mitigation of wind erosion of soil.

关键词： remote sensing geographic information system wind erosion of soil desertification control in China WEDI

Wetland vegetation biomass estimation and mapping from Landsat ETM data: a case study of Poyang Lake

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Journal of geographical sciences 2002年第1期12卷 35-41页

作者： LI Ren-dong1, 2. LIU Ji-yuan2.(1. institute of Geodesy and Geophysics, cas, Wuhan 430077, China {2., cas, beijing 100101 China) institute of Geodesy and Geophysics CAS Wuhan China institute of geographic {2. and natural resources research CAS Beijing China

Poyang Lake is the largest freshwater lake in China. This paper conducted a digital and rapid investigation of the lake’s wetland vegetation biomass using Landsat ETM data acquired on April 16, 2.00. First, utilizing the false color composite derived from the ETM data as one of the main references, the authors designed a reasonable sampling route for field measurement of the biomass, and carried it out on April 18–2., 2.00. Then after both the sampling data and the ETM data were geometrically corrected to an equal-area projection of Albers, linear relationships among the sampling data and some transformed data derived from the ETM data and the ETM 4 were calculated. The results show that the sampling data is best relative to the band 4 data with a high correlation coefficient of 0.86, followed by the DVI and NDVI data with 0.83 and 0.80 respectively. Therefore, a linear regression model, which was based on the field data and band 4 data, was used to estimate the total biomass of entire Poyang Lake, and then the map of the biomass distribution was compiled.

关键词： Poyang Lake biomass wetland vegetation Landsat ETM data

Dynamic change of net primary productivity and fractional vegetation cover in the Yellow River Basin using multi-temporal AVHRR NDVI Data

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Journal of geographical sciences 2002年第1期12卷 29-34页

作者： SUN Rui1, LIU Chang-ming2. ZHU Qi-jiang1 (1. Department of Geography, beijing Normal University, beijing 100875, China {2., cas, beijing 100101, China) Department of Geography Beijing Normal University 北京 100875 institute of geographic {2. and natural resources research CAS 北京 100101

An exponential relationship between net primary productivity (NPP) and integrated NDVI has been found in this paper. Based on the relationship and using multi-temporal 8 km resolution NOAA AVHRR-NDVI data, the spatial distribution and dynamic change of NPP and fractional vegetation cover in the Yellow River Basin from 1982.to 1999 are analyzed. Finally, the effect of rainfall on NDVI is examined. Results show that mean NPP and fractional vegetation cover have an inclining trend for the whole basin, and rainfall in flood season influences vegetation cover most.

关键词： net primary productivity fractional vegetation cover rainfall remote sensing

GIS平台构建在黄河流域水循环研究中的应用

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水土保持学报 2003年第4期17卷 102-104,109页

作者：李道峰丁晓雯刘昌明北京师范大学环境科学研究所水环境模拟国家重点实验室北京100875

探讨了GIS在水文学研究中的一般模式,在构建黄河流域水循环GIS平台时采用GIS与水文模型松散结合方式,基于VisualBasic可视化开发语言,以地理信息系统组件为基本单元,构建了用于存储和管理黄河流域水循环空间和属性数据的平台,并将所涉... 详细信息

探讨了GIS在水文学研究中的一般模式,在构建黄河流域水循环GIS平台时采用GIS与水文模型松散结合方式,基于VisualBasic可视化开发语言,以地理信息系统组件为基本单元,构建了用于存储和管理黄河流域水循环空间和属性数据的平台,并将所涉及到的各类数据统一坐标、统一格式、统一编码储存到平台中,为黄河流域水循环要素分析和水文过程研究提供数据支持。

关键词： GIS 黄河流域水循环研究应用水文学研究地理信息系统

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铁路施工期不同下垫面土壤侵蚀区域差异研究

水土保持学报 2003年第6期17卷 70-73页

作者：李忠武蔡强国吴淑安湖南大学环境科学与工程系湖南长沙410082 中国科学院地理科学与资源研究所北京100101

区域性是地理学的重要特点之一。本研究从区域差异性着手,应用对比方法,模拟研究了辽宁兴城和贵州威宁2.区域在铁路工程施工期工程措施所形成的各类人工地貌的侵蚀产沙、产流特征。结果表明,由于地表自然状况的南北区域差异,导致2.研... 详细信息

区域性是地理学的重要特点之一。本研究从区域差异性着手,应用对比方法,模拟研究了辽宁兴城和贵州威宁2.区域在铁路工程施工期工程措施所形成的各类人工地貌的侵蚀产沙、产流特征。结果表明,由于地表自然状况的南北区域差异,导致2.研究区在工程措施影响下的各类人为地貌的产沙产流具有明显的差异,具体表现为:北部研究区的产沙产流时间迟于南部;相同时间内累积产沙量、产流量则北部小于南部,表现出明显的地域差异性。

关键词：区域性差异性侵蚀产沙

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考虑土地覆被的神经网络径流模拟研究

水电能源科学 2004年第2期22卷 13-15页

作者：尹雄锐张翔夏军刘蕾武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

针对土地利用/土地覆被变化对水文过程的影响问题,应用神经网络,对比研究了加入土地利用/土地覆被因子前后,流域径流模拟预测精度的变化。实例应用表明,考虑土地利用/土地覆被因子有助于提高神经网络模型模拟和预测精度。

关键词：神经网络土地利用/土地覆被变化模拟预测

Relationship between Environmental Pollution of Coal Mine and Spectral Characteristics of Nearby Plants

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Journal of University of Science and Technology beijing 2001年第1期8卷 10-14页

作者： Liqing Lei institute of geographic {2. and natural resources research, Chinese Academy of {2., beijing 100101, China Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

Remote sensing technology, as the most advanced method for collecting data, along with the common ways often used in the past on research of environmental science, was integrated to study the relationship between environmental pollution of coal mine and spectral characteristics of nearby plants. With compositive index and mean reflectivity at near infrared, a regression equation was established, and a conclusion was made that spectral reflectivity can be used to distinguish regions with different pollution degree. Through testing with real status of the research region, it is verified that this kind of integration and conclusion not only are helpful for human being in controlling the movement law of pollutants and the corresponding change of coal mine environmental quality but also bring a new way for the research of environment problems of coal mine.

关键词： remote sensing spectral characteristics reflectivity pollution index compositive index atmospheric pollution

Relationship between erosion and sediment yield in drainage basins of loess gully-hilly areas

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Journal of geographical sciences 2001年第1期11卷 71-79页

作者： CHEN Hao (institute of geographic {2. and natural resources research, cas, beijing 100101, China) institute of geographic {2. and natural resources research CAS Beijing China

From a long-term point of view, the balance between erosion and sediment yield in a drainage system can basically realize, i.e., the delivery ratio can be close to 1. However, substantial variations among individual rainfall events or between annual delivery ratio exist, causing frequent sediment retaining or re-erosion and re-delivery of the retained sediments in a short period of time. Thus the delivery ratio will be 1. The sediment delivery ratio is closely related to the spatial distribution of rainfall and magnitude of rise and fall of peak flood and that of runoff depth in the drainage system. Delivery ratio of single event in a drainage system and changes of delivery capacity of silt-laden runoff in various classes of gullies can be expressed by transformation mechanism of shear force of a single rainstorm event with flood resulting from increase and decrease of peak flood per unit area.

关键词： delivery ratio interaction flood and geomorphology dynamic mechanism rainstorm flood

Soil erosion and management on the Loess Plateau

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Journal of geographical sciences 2001年第1期11卷 53-70页

作者： CAI Qiang-guo (institute of geographic {2. and natural resources research, cas, beijing 100101, China) institute of geographic {2. and natural resources research CAS Beijing China

The Loess Plateau is well known to the world for its intense soil erosion. The root cause for river sedimentation of Yellow River (Huanghe) and its resultant “hanging river” in certain section is soil and water loss on the Loess Plateau. The Loess Plateau has a long cultivation history, hence population growth, vegetation degeneration and plugging constitute the chief reason for serious soil and water loss on Loess Plateau. This paper analyses several successful cases and failures in soil conservation, presents practical soil conservation technique and related benefit analysis, and discusses some effective methods adopted in China in soil erosion control, research directions and future perspectives on Loess Plateau.

关键词： soil erosion control technique management Loess Plateau