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1.
Remote sensing imagery at widely varying scales is used in the analysis of the soil-vegetation cover of the west-central Siberia. Space imagery and smaller-scale air photographs initially are used to divide a study area into basic soil-vegetation complexes based on the criterion of figure outline. The internal structure of the complexes are then analyzed in greater detail, using larger-scale air photographs and a standard interpretation key based on selected field observations. Tonal-textural variations establish the ecological affiliations of separate elements within each complex and their dynamic states at a particular point in time. Translated from: Geografiya i prirodnyye resursy, 1985, No. 2, pp. 112-119.  相似文献   

2.
Procedures for mapping the soil-vegetation structure of West Siberia on the basis of remote sensing images are described. Four principal stages are involved: interpretation of individual structures on the images; determination of the functions of the interpreted structures; classification of soil-vegetation structures; and mapping of the territory by types of soil-vegetation structures (micro-, meso- and microstructures). Particular attention is given to detection of soil-vegetation hydromorphism using remote sensing imagry, important in the swampy Western Siberian environment, and the special problems related to image scale. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1990, No. 1, pp. 138–145.  相似文献   

3.
The authors describe the results of an extensive geomorphologic mapping program for the Kura-Araks Lowland of Azerbaijan, designed to increase the level of background information available for the rational planning and operation of irrigation systems. A particular focus is placed upon the identification and depiction of landforms of the Lowland exerting an influence on hydrogeologic conditions, the ground water regime, and on crop cultivation patterns. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1995, No. 4, pp. 169-171.  相似文献   

4.
A method is described for the mapping of exogenous geomorphologic hazards (mass movements, frost heaving, suffosion, melting of permafrost) in the Lake Baykal area using space imagery. Black-and-white photography from the Salyut-4 space station (1:2,100,000 scale) was used as a base for the preparation of a series of maps depicting natural conditions (morphotectonic and physical geographic regions, faults, climate, dominant exogenous processes) used as a base for compiling a map of planning and engineering measures for the prevention and amelioration of geomorphologic hazards. Translated from: Geografiya i prirodnyye resursy, 1985, No. 2, pp. 59-67.  相似文献   

5.
The basic methodology of structural-landscape mapping is outlined: (a) preliminary delineation, using remote sensing imagery, of macroregions where surface topography corresponds generally to underlying geologic structure; and (b) identification and mapping (at smaller scales) of landscape anomalies within these regions which indicate structural-tectonic disturbances of a particular type (oil-gas traps, for example). Various types of structural-landscape maps are then compared for the purpose of demonstrating both the multiplicity of uses for such maps and the importance of carefully selecting indices for mapping and optimal designs for specific uses, such as oil and gas exploration. Translated from: Izvestiya, Vsesoyuznoye Geograficheskoye Obshchestvo, 1984, No. 3, pp. 218-224.  相似文献   

6.
A procedure is described for the use of nighttime space imagery in the mapping of an urban settlement hierarchy in the Federal Republic of Germany. City “brightness” values provide surrogate measures of urban settlement density, which are then mapped isarithmically. The resulting statistical surface is then divided into regions (first- and second-order settlement systems), and the map compared with one produced by quantitative (cluster analysis) techniques. The two regionalization schemes produce remarkably similar results, although the map compiled from the space image contained a greater number of regions, and was more detailed in other ways. Translated from: Vestnik Leningradskogo Universiteta, seriya geografiches-kaya, 1984, No. 6, pp. 112-114.  相似文献   

7.
A spectral linear-mixing model using Landsat ETM+ imagery was undertaken to estimate fraction images of green vegetation, soil and shade in an indigenous land area in the state of Mato Grosso in the central-western region of Brazil. The fraction images were used to classify different types of land use and vegetation cover. The fraction images were classified by the following two methods: (a) application of a segmentation based on the region-growing technique; and (b) grouping of the regions segmented using the per-region unsupervised classifier named ISOSEG. Adopting a 75% threshold, ISOSEG generated 44 clusters that were grouped into eight land-use and vegetation-cover classes. The mapping achieved an average accuracy of 83%, showing that the methodology is efficient in mapping areas of great land-use and vegetation-cover diversity, such as that found in the Brazilian cerrado (savanna).  相似文献   

8.
Geological mapping of the Vindhyan and Deccan Trap terrain around Jhalawar was accomplished by aerial photointerpretation with limited field checks in parts, by conventional field mapping for part of the area and also by interpretation of LANDSAT imagery. A comparative assessment of the data producing capability and accuracy of these methods is made from the case study. Major geological formations comprising Semri, Kaimur, Rewa and Bhander groups of Vindhyan supergroup, Deccan Trap and recent fluvial sediments are equally interpretable from all three level (i.e. ground, air and space) surveillance data. All the members and units are mappable on air photos and on ground but not on the LANSAT imagery. It is difficult to plot all the flows and flow units of Deccan Trap on a topographic base map during conventional field mapping but these are more or less separable on aerial photos. Structural trends are decipherable by photointerpretation but lineaments are well depicted on LANDSAT imagery. Physical and petrological characters of rocks can, however, only be studied in situ and by laboratory analysis of samples. Aerial photointerpretation techniques can be applied for geological mapping of Vindhyan and Deccan Trap terrain with high degree of confidence and reasonable accurate maps can be generated. LANDSAT imagery are useful for generation of small scale reconnalssance and lineament pattern maps. The best system of mapping such terrain would be photointerpretation with limited field check and collection of essential groundtruth and specimens for laboratory analysis along selected traverses thus minimising the time and cost of survey.  相似文献   

9.
This paper demonstrates how ice-surface relief identified on space imagery can be used in mapping selected elements of the geologic structure of the Antarctic Peninsula. The mapping procedure is based on the fact that all major subglacial relief forms appear, albeit in subdued form, on the surface of slow moving and relatively thin ice sheets. Since subglacial bedrock relief reflects geologic structure, particular surface configurations of ice identified on space imagery can be used as indicators of major structural elements. Examples of the procedure, including imagery of ice relief and corresponding cartographic representations of underlying structure are provided for faults and ring structures. Translated from: Antarktika, AN SSSR Mezhduvedomstvennaya komissiya po izucheniyu Antarktiki, Doklady komissii [USSR Academy of Sciences Joint Commission on Antarctic Research, Commission Report], No. 24. Moscow, 1985, pp. 50-55. An article demonstrating the application of these methods in the compilation of a geologic map for a part of the Antarctic Peninsula will appear in a later issue.  相似文献   

10.
Buildings, as impervious surfaces, are an important component of total impervious surface areas that drive urban stormwater response to intense rainfall events. Most stormwater models that use percent impervious area (PIA) are spatially lumped models and do not require precise locations of building roofs, as in other applications of building maps, but do require accurate estimates of total impervious areas within the geographic units of observation (e.g. city blocks or sub-watershed units). Two-dimensional mapping of buildings from aerial imagery requires laborious efforts from image analysts or elaborate image analysis techniques using high spatial resolution imagery. Moreover, large uncertainties exist where tall, dense vegetation obscures the structures. Analyzing LiDAR point-cloud data, however, can distinguish buildings from vegetation canopy and facilitate the mapping of buildings. This paper presents a new building extraction approach that is based on and optimized for estimating building impervious areas (BIA) for hydrologic purposes and can be used with standard GIS software to identify building roofs under tall, thick canopy. Accuracy assessment methods are presented that can optimize model performance for modeling BIA within the geographic units of observation for hydrologic applications. The Building Extraction from LiDAR Last Returns (BELLR) model, a 2.5D rule-based GIS model, uses a non-spatial, local vertical difference filter (VDF) on LiDAR point-cloud data to automatically identify and map building footprints. The model includes an absolute difference in elevation (AdE) parameter in the VDF that compares the difference between mean and modal elevations of last-returns in each cell.

The BELLR model is calibrated for an extensive inner-city, highly urbanized small watershed in Columbia, South Carolina, USA that is covered by tall, thick vegetation canopy that obscures many buildings. The calibration of BELLR used a set of building locations compiled by photo-analysts, and validation used independent building reference data. The model is applied to two residential neighborhoods, one of which is a residential area within the primary watershed and the other is a younger suburban neighborhood with a less-well developed tree canopy used as a validation site. Performance results indicate that the BELLR model is highly sensitive to concavity in the lasboundary tool of LAStools® and those settings are highly site specific. The model is also sensitive to cell size and the AdE threshold values. However, properly calibrated the BIA for the two residential sites could be estimated within 1% error for optimized experiments.

To examine results in a hydrologic application, the BELLR estimated BIAs were tested using two different types of hydrologic models to compare BELLR results with results using the National Land Cover Database (NLCD) 2011 Percent Developed Imperviousness data. The BELLR BIA values provide more accurate results than the use of the 2011 NLCD PIA data in both models. The VDF developed in this study to map buildings could be applied to LiDAR point-cloud filtering algorithms for feature extraction in machine learning or mapping other planar surfaces in more broad-based land-cover classifications.  相似文献   


11.
With increasing attention being paid to sustainable urban development and human habitation improvement, urban ecological land cover (UELC), i.e., surface water and green space, has played an important role of the highly compact inner urban regions. In this study, we developed an efficient approach for UELC mapping by coupling Sentinel-2 multi-spectral imagery and Google Earth high-resolution imagery. In contrast with the conventional single-source and multi-source imagery-based classification methods, the proposed method respectively achieved the highest overall accuracies of 91.50% and 94.05% in the UELC mapping for two test sites (i.e. Shanghai and Seoul). The proposed method is used for urban surface mapping among six world-class cities. For an in-depth analysis of the landscape structures for inner urban regions, seven landscape metrics are introduced for the quantification of the UELC structure based on the obtained high-precision UELC maps. The result shows that London appears to have the best UELC-induced ecological quality, that is, with high percentage of landscape, area-weighted mean fractal dimension, edge density, Shannon’s evenness index values and a low contagion index value, while Tokyo is exactly the opposite. Several common characteristics found through the statistical analysis are: 1) all the inner-city regions have small UELC coverage (< 50%) and low shape complexity; 2) green space generally contributes more to urban eco-environment than the urban surface water; and 3) all cities show high landscape consistency in the inner urban region.  相似文献   

12.
A quantitative method for mapping the contemporary dynamics of ecosystems is described. Particular reference is to the mapping of the desertification of complex ecosystems of the lower reaches of the Amudar'ya using a time series of four surveys. The types of ecological transitions identified from remote sensing imagery and their frequencies are described. Translated by Edward Torrey, Alexandria, VA 22308 from: Izvestiya Akademii Nauk, seriya geograficheskaya, 1994, No. 5, pp. 112-122.  相似文献   

13.
A brief review paper focuses on Soviet strategies for the use of space imagery, particularly photographic products (1:2,000,000 to 1:4,200,000 scale) from manned spaceflights, in the revision of small-scale general reference maps. Principles for the interpretation and mapping of basic map elements appearing on space photographs are outlined. Space photographs provide for reduction in time spent in map editing and the more correct analysis of the reliability of information and its generalization. A technology of map revision based on the joint use of original photographs and photomaps, with the transfer of revisions from photomaps to map originals, is proposed. Translated from: Geodeziya i kartografiya, 1986, No. 8, pp. 29-33.  相似文献   

14.
The paper outlines a strategy for environmental management based on the joint use of space imagery and existing thematic map sets in monitoring the state of the environment in areas known as territorial human-environment complexes, proposed as regional-level units of nature management. Space imagery is also instrumental in the identification of these complexes prior to the onset of monitoring, a subject which is addressed in some detail at the start of the paper. Most extensive coverage is devoted to the organization and operation of a centralized, interdisciplinary data bank of remote sensing imagery, from which scenes are processed and interpretation maps distributed according to the specific needs of user organizations. Translated from: Geografiya i prirodnyye resursy, 1986, No. 2, pp. 138-142.  相似文献   

15.
Different image processing algorithms have been evaluated in the context of geological mapping using Landsat TM data. False color composites, the principal component imagery, and IHS decorrelation stretching method for Landsat-5 TM data have been found useful for delineating the regional geological features, mainly to provide the maximum geological information of the studied area . The study testifies that using which image processing yields best results for geological mapping in arid and semiarid regions by preserving morphological and spectral information. Generally, the studied area can be divided into three main geological units: Basaltic intrusive rocks, Metamorphic with varying intensities and Sedimentary rocks.  相似文献   

16.
The authors describe how remote sensing imagery can be employed in the identification of different types of chernozem soils in a predominantly agricultural zone (forest steppe), where natural vegetation (normally one of the best vegetation indicators) has been largely displaced by farm fields. A multi-stage methodology is outlined whereby small-scale imagery is used to delineate large regions of similar bioclimatic-geologic characteristics, from which areas of similar soil formation conditions are distinguished. Multispectral and multitemporal space imagery then is employed to detect less salient ecological-soil differences that can affect phototone and image texture. Translated by Edward Torrey, Alexandria, VA 22308 from: G. V. Dobrovol'skiy and V. L. Andronikov, eds., Aerokosmicheskiye metody v pochvovedenii i ikh ispol'zovaniye v sel'skom khozyaystve: sbornik nauchnykh trudov [Remote Sensing Methods in Soil Science and Their Utilization in Agriculture: A Collection of Scientific Works]. Moscow: Nauka, 1990, pp 103–109.  相似文献   

17.
Different image processing algorithms have been evaluated in the context of geological mapping using Landsat TM data. False color composites, the principal component imagery, and IHS decorrelation stretching method for Landsat-5 TM data have been found useful for delineating the regional geological features, mainly to provide the maximum geological information of the studied area. The study testifies that using which image processing yields best results for geological mapping in arid and semiarid regions by preserving morphological and spectral information. Generally, the studied area can be divided into three main geological units: Basaltic intrusive rocks, Metamorphic with varying intensities and Sedimentary rocks.  相似文献   

18.
The authors outline the general policy governing the use of remote sensing in Siberian mineral exploration—as a tool in the structural-geomorphologic mapping of potential mineral-bearing locations. Such maps are used to infer geologic structure (and endogenous conditions for mineral formation) and the character of contemporary exogenous processes (and conditions of transport and concentration of mineral residues) from geoindicators in surface terrain visible from space. Uses of space imagery in the study of seismic activity and engineering geomorphology are also described. Translated from: Kompleksnyye aerokosmicheskiye Issledovaniya Sibiri, A. L. Yanshin and L. K. Zyat'kova, eds. Novosibirsk: Nauka, 1984, pp. 5-14.  相似文献   

19.
The relative abundance and distribution of trees in savannas has important implications for ecosystem function. High spatial resolution satellite sensors, including QuickBird and IKONOS, have been successfully used to map tree cover patterns in savannas. SPOT 5, with a 2.5 m panchromatic band and 10 m multispectral bands, represents a relatively coarse resolution sensor within this context, but has the advantage of being relatively inexpensive and more widely available. This study evaluates the performance of NDVI threshold and object based image analysis techniques for mapping tree canopies from QuickBird and SPOT 5 imagery in two savanna systems in southern Africa. High thematic mapping accuracies were obtained with the QuickBird imagery, independent of mapping technique. Geometric properties of the mapping indicated that the NDVI threshold produced smaller patch sizes, but that overall patch size distributions were similar. Tree canopy mapping using SPOT 5 imagery and an NDVI threshold approach performed poorly, however acceptable thematic accuracies were obtained from the object based image analysis. Although patch sizes were generally larger than those mapped from the QuickBird image data, patch size distributions mapped with object based image analysis of SPOT 5 have a similar form to the QuickBird mapping. This indicates that SPOT 5 imagery is suitable for regional studies of tree canopy cover patterns.  相似文献   

20.
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