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1.
An analysis made of the worldwide existing geoinformation systems (HydroSHEDS, CCM, Ecrins, WBD, etc.) suggests that there are as yet no models of adequate quality for the basin boundaries of small rivers in the European part of Russia. For the territory of the European part of Russia with a total area of more than 4 mln. km2 the GIS technology tools were used to construct the electron vector map of river basins and their interbasin spaces. The map thus obtained displays the basins of first-order rivers for a given level of generalization (sc 1:1 000 000). The GMTED2010 model was used as the digital elevation model. A total of 63 553 basin geosystems were identified on the map, averaging 68 km2 in area. Accuracy verification of identifying the basin boundaries showed a good agreement of areal and geometric characteristics of the method used with expert approach. In test areas, the men difference of the indicators of the area of the basins identified automatically and by use of the expert approach made up 3.6%. For areas with weakly dissected lowland topography this error does not exceed 5% while it is about 2% in areas with relatively dissected elevated topography. The basin geosystems thus identified are operational-territorial units with respect to which the geospatial data base is generated to characterize the natural-resource potential of the European territory of Russia. An example is provided for the generation of the geospatial database containing hydrological information covering 1763 hydrological stations collecting streamflow data.  相似文献   

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We examine the methodological issues and some results of landscape mapping of the Upper Yenisei basin (the Nazarovskaya, Kanskaya, Minusinskaya and Tuvinskaya depressions) at a scale of 1:1 000 000. A fragment of the map of the geosystems is provided, and the territory’s landscape structure is described.  相似文献   

5.
Natural-resource space (NRS) is a set of resource-containing components of geographical environment as taken in a spatiotemporal continuum. We suggest different types and levels of NRS: global, national, regional and local; space of homogeneous resources, and territorial combinations of natural resources, and others. Borders are identified as really existing transitional zones between NRS of different types and levels, and institutional boundaries. Ecological-resource space is singled out, given a connectivity of national and regional NRS, with portions of transboundary geosystems going beyond their boundaries.  相似文献   

6.
Landform classification is one of the most important procedures in recognizing and dividing earth surface landforms. However, topographical homogeneity and differences in regional-scale landforms are often ignored by traditional pixel- and object-based landform classification methods based on digital elevation models (DEMs). In this work, a drainage basin object-based method for classifying regional-scale landforms is proposed. Drainage basins with least critical areas are first delineated from DEMs. Then, terrain derivatives of mean elevation, mean slope, drainage density, drainage depth, and terrain texture are employed to characterize the morphology of the drainage basins. Finally, a decision tree based on the topographical characteristics of the drainage basins is constructed and employed to determine the landform classification law. The experiment is validated in the landform classification of regional-scale loess areas in China. Results show that clear boundaries exist in different landforms at the regional scale. Landform type in a specific region shows significant topographical homogeneity under its specific regional geomorphological process. Classification accuracies are 87.3 and 86.3% for the field investigation and model validation, respectively. Spatial patterns of classified landforms and their proximity to sediment sources and other factors can be regarded as indicators of the evolutionary process of loess landform formation.  相似文献   

7.
Using conventional visual interpretation in lineament analysis presents two main problems. The first is subjectivity, introduced because of the bias of various interpreters. The second problem is that lineaments detected from satellite images are constrained by the direction of the illumination source. Since lineament identification mainly involves recognition of diagnostic morphological features, the use of digital elevation can contribute significant information about these features. Further, in generating images using digital elevation data, the direction of illumination can easily be controlled. Thus, the use of digital elevation data offers the possibility of revealing features not apparent in regular satellite images.We discuss a sequential line detection method for extraction of linear features from digital elevation data. In this method, raw elevation data is used for generating shaded relief images using the Lambertian reflection model, wherein the illumination direction is controlled by the user. The Directional Segment Detection Algorithm (DSDA) is used for detecting linear topographic features in user-defined trends. Locational information about these linear features is stored in the computer as coordinate pairs amenable to editing and subsequent analysis. Finally, three-dimensional terrain models are generated by combining the digital elevation data and satellite images. The experiments were carried out using digital elevation data of southwest Japan and Landsat MSS data.  相似文献   

8.
Urban clusters are the expected products of high levels of industry and urbanization in a country, as well as being the basic units of participation in global competition. With respect to China, urban clusters are regarded as the dominant formation for boosting the Chinese urbanization process. However, to date, there is no coincident, efficient, and credible methodological system and set of techniques to identify Chinese urban clusters. This research investigates the potential of a computerized identification method supported by geographic information techniques to provide a better understanding of the distribution of Chinese urban clusters. The identification method is executed based on a geographic information database, a digital elevation model, and socio-economic data with the aid of ArcInfo Macro Language programming. In the method, preliminary boundaries are identified accord-ing to transportation accessibility, and final identifications are achieved from limiting city numbers, population, and GDP in a region with the aid of the rasterized socio-economic dataset. The results show that the method identifies nine Chinese urban clusters, i.e., Pearl River Delta, Lower Yangtze River Valley, Beijing-Tianjin-Hebei Region, Northeast China Plain, Middle Yangtze River Valley, Central China Plains, Western Taiwan Strait, Guanzhong and Chengdu-Chongqing urban clusters. This research represents the first study involving the computerized identification of Chinese urban clusters. Moreover, compared to other related studies, the study’s approach, which combines transportation accessibility and socio-economic characteristics, is shown to be a distinct, effective and reliable way of identifying urban clusters.  相似文献   

9.
This paper further develops the ideas of V. B. Sochava’s Siberian school of thematic mapping concerning an integral approach in generating synthesis and assessment maps of the habitat on objective grounds confirmed by quantitative calculations. Maps of the natural environment display the invariant structure of the sites of a territory and their variable states. Integral indicators of the state of environment combine differentquality spatial information on the geographical location of the sites having regard to the scientific principles of qualimetry. An unbiased calculation of integral indicators is ensured through the use of the method of principal component analysis. The first principal component characterizes a maximum of variation in information on the geosystem, and the second component refers to a stable environment background. Their difference for each location corresponds to the potential of geosystem variability. The resulting integral indicators are displayed on assessment cartograms. The entire array of independent principal components is used for a classification of geosystems using the method of k-means clustering to create the typological map of the territory. Calculations are based on data for forest management of the Slyudyanka Leskhoz within the boundaries of the Slyudyanka municipal district of Irkutsk oblast. The territorial norm of the geographical environment corresponds to geosystems of the mountain-taiga belt of the Siberian stone pine and larch taiga on different-aspect slopes. Negative deviations from the norm are induced by high-mountain goletz and subgoletz geosystems on steep slopes, and positive deviations correspond to flat interfluves and gentle slopes.  相似文献   

10.
Urban clusters are the expected products of high levels of industry and urbanization in a country, as well as being the basic units of participation in global competition. With respect to China, urban clusters are regarded as the dominant formation for boosting the Chinese urbanization process. However, to date, there is no coincident, efficient, and credible methodological system and set of techniques to identify Chinese urban clusters. This research investigates the potential of a computerized identification method supported by geographic information techniques to provide a better understanding of the distribution of Chinese urban clusters. The identification method is executed based on a geographic information database, a digital elevation model, and socio-economic data with the aid of ArcInfo Macro Language programming. In the method, preliminary boundaries are identified according to transportation accessibility, and final identifications are achieved from limiting city numbers, population, and GDP in a region with the aid of the rasterized socio-economic dataset. The results show that the method identifies nine Chinese urban clusters, i.e., Pearl River Delta, Lower Yangtze River Valley, Beijing-Tianjin-Hebei Region, Northeast China Plain, Middle Yangtze River Valley, Central China Plains, Western Taiwan Strait, Guanzhong and Chengdu-Chongqing urban clusters. This research represents the first study involving the computerized identification of Chinese urban clusters. Moreover, compared to other related studies, the study's approach, which combines transportation accessibility and socio-economic characteristics, is shown to be a distinct, effective and reliable way of identifying urban clusters.  相似文献   

11.
基于数字高程模型的水系提取算法   总被引:1,自引:0,他引:1  
介绍基于地表径流漫流模型从数字高程模型 (DEM )提取水系的一系列算法。这套算法完成下述功能 :洼地的识别和填充、平地的抬升、水流方向的确定、上游集水面积的确定和河流栅格网络的生成以及水系的生成和水流线等级的确定。  相似文献   

12.
雅鲁藏布江流域海拔高差约达7 000 m,气候条件复杂、生态系统类型多样,植被格局空间变化显著.笔者基于1:100万植被类型图、SPOT_VEGETATION NDVI数据集和数字高程模型(DEM),综合运用GIS空间分析技术,提取与定量分析了流域主要植被类型、空间分布特征,并结合海拔梯度、气候条件变化探讨了流域植被格局与NDVI空间变化的耦合关系.结果表明:(1) 雅鲁藏布江流域植被类型包括针叶林、阔叶林、灌丛、荒漠、草原、草丛、草甸、高山植被等11个植被型组,21个植被型,其中米林宽谷的植被型最多,自下游至上游的山南宽谷、日喀则宽谷及马泉河宽谷随着海拔梯度的变化,植被类型多样性总体呈下降趋势.(2) 随着海拔的增加,植被型组和植被型的个数均呈先增大后减小的趋势,以海拔3000~4 000 m和4 000~5 000 m最多,流域植被格局的垂直地带性显著.(3) 流域植被格局与NDVI变化表现出较好的空间一致性.针叶林、阔叶林和草丛等3个植被型组的NDVI值均以10-12月最大,其余8个植被型组的NDVI值均以7-9月最大、1-3月最小.海拔3 000 m是流域尺度植被格局变化的一个转折点.  相似文献   

13.
Presented are the technique and results of studying the landscape structure of the north-west of Western Siberia on the basis of the Hansen mosaic dataset consisting of elements covering the entire territory of the Earth. To study this area used a synthesis of classical methods of thematic system mapping as described in the doctrine of geosystems of V. B. Sochava, and automated interpretation of remote sensing data and mapping using GIS technologies. The method of geoinformational mapping of the landscape structure with the use of MultiSpec and Quantum GIS software programs for the purpose of drawing up real-time raster landscape maps is shown. In drawing up the map and the legend, the principle of geomic system-hierarchical representation of the territory as a complex multi-level “bottom-up” structure from topological-level geosystems (groups and classes of landscape facies) to regional-level geosystems (geoms, groups and classes of geoms) was used. Compilation of operational raster landscape maps of the north-west of Western Siberia involved multilevel automated interpretation of the Hansen mosaic dataset and mapping of areas (clusters) on images with different brightness characteristics, with the landscape structure of key areas and stationary physical and geographical profiles. A characteristic of this approach also implies using a dynamic classification of geosystems based on the study of their variable states. Such an approach permits a monitoring of changes in landscape structure and its areas and the intensity of anthropogenic impacts on forest and marsh landscapes, and determination of permissible pressure on geosystems in areas with high technogenic pressure of the oil and gas complex represented by the north-west of Siberia. An automated processing of data based on a supervised classification of territorial objects allows for the elimination of inaccuracies arising in visual image interpretation. Raster landscape maps can be used both for a further generation of vector maps and as a real-time information base for purposes of environmental management and protection.  相似文献   

14.
分布式水文模型结合遥感研究地表蒸散发   总被引:7,自引:5,他引:2  
地表蒸散发是研究土壤-植被-大气系统水热平衡的关键因子。用改进的DHSVM分布式水文模型对汉江上游子午河流域蒸散发进行模拟。根据流域特点,主要进行TM遥感数据的大气校正和几何校正,在此基础上得到叶面积指数和土地覆盖等地表参数;再利用GIS技术基于DEM求出坡度、坡向和地形指数等因子。分析了蒸散发时空分布特征,表明日尺度蒸散发空间分布差异较大。初步验证了结果,表明模型在中国典型湿润区小流域取得较好效果。  相似文献   

15.
《Geomorphology》1988,1(2):131-141
A method of generating drainage networks and catchment boundaries from gridded ground elevation data (a digital terrain model) is presented. The method includes an algorithm for coping with localised low points in the data. The paper suggests two objective ways of comparing the conventionally mapped with the automatically generated drainage network. Emphasis is placed on the way that this approach is capable of benefiting a variety of hydrological applications, in particular the automatic estimation of flow statistics from catchment characteristics.  相似文献   

16.
Digital elevation and remote sensing data sets contain different, yet complementary, information related to geomorphological features. Digital elevation models (DEMs) represent the topography, or land form, whereas remote sensing data record the reflectance/emittance, or spectral, characteristics of surfaces. Computer analysis of integrated digital data sets can be exploited for geomorphological classification using automated methods developed in the remote sensing community. In the present study, geomorphological classification in a moderate- to high-relief area dominated by slope processes in southwest Yukon Territory, Canada, is performed with a combined set of geomorphometric and spectral variables in a linear discriminant analysis. An automated method was developed to find the boundaries of geomorphological objects and to extract the objects as groups of aggregated pixels. The geomorphological objects selected are slope units, with the boundaries being breaks of slope on two-dimensional downslope profiles. Each slope unit is described by variables summarizing the shape, topographic, and spectral characteristics of the aggregated group of pixels. Overall discrimination accuracy of 90% is achieved for the aggregated slope units in ten classes.  相似文献   

17.
程东亚  李旭东 《地理研究》2020,39(6):1427-1438
研究流域人口分布与地形的关系,有助于了解地理环境对人口分布的影响。以贵州省乌江流域为研究区,基于DEM数据和人口数据,提取海拔、坡度、起伏度等地形因子,研究人口分布与地形因子的关系。研究结论:① 人口数量在海拔800~1400 m的地区超过60%,人口密度在1000~1200 m的地区最高。② 人口数量与人口密度随着坡度上升总体呈下降趋势。③ 人口密度在起伏度小于50 m的地区超过1000人/km 2,人口密度随着起伏度上升总体呈下降趋势。  相似文献   

18.
We examine the sequence of changes in the structure of the geosystems of the Primorsky Range (Baikal region) for the last 6000 years, based on a continuous recording of fluctuations of the vegetation reconstructed from spore-pollen complexes of a high peat bog. We determined the chronological timeframe of paleogeographical events. The study showed that there occurred a radical structure transformation of the geosystems in the mid-late Holocene, along with a recurrence of similar landscape transformations caused by the instability of natural conditions.  相似文献   

19.
The structure and dynamics of geosystems in the northwestern part of Western Siberia is considered using the Kazym-Lyamin interfluve, based on the landscape-assessment map for the middle part of the Khanty-Mansi Autonomous District. The study used the landscape structural-dynamical approach and the methods of studying the spatio-temporal dynamics of taiga geosystems.  相似文献   

20.
Using the glaciers of the Munku-Sardyk massif as an example, we examine the patterns of changes of glaciological landscapes as revealed through instrumental observations. We present the quantitative parameters of the dynamics of nival-glacial geosystems obtained by using state-of-the-art remote sensing and GIS analysis facilities. Interesting new features reflecting the state of geosystems are described, and particularizing geoinformation calculations and a mapping are performed for a subsequent monitoring of their state.  相似文献   

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