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An analysis is made of conditions believed to be optimum for a stereoscopic survey of the Earth's surface by a synthetic-aperture radar on board a spacecraft. Variants for construction of an orbiting stereosystem and factors contributing to a radiometric mismatch of stereopair images are examined. Analysis and choice of optimum conditions for a stereophotogrammetric survey are oriented toward facilitating the computer processing of radar images for the purpose of obtaining digital terrain models.  相似文献   

3.
An experiment is described in which multiscalar remote sensing imagery is sequentially employed in the detection of various rankings of soil types endemic to the taiga natural zone in the northern USSR. Relief features, vegetation associations, extent of surface water, and drainage patterns visible on imagery at scales from 1:12,000,000 to 1:5,000, also examined at low altitude and in the field at a series of test sites, served as indicators of various soil cover types. Considerable attention is given to an explanation of why these features can be considered valid indicators of taiga soil types as well as to the appearance of the indicators on band-specific (black-and-white) and color composite imagery. Translated from: Izvestiya Akademii Nauk SSSR, seriya geograficheskaya, 1987, No. 3, pp. 87-99.  相似文献   

4.
Atmospheric boundary-layer stratification exerts a considerable influence on side-looking radar imagery of the sea surface in the centimeter range. Characteristic cellular structures present on the imagery under conditions of instability in the atmospheric boundary layer do not appear on images recorded under stable atmospheric conditions. The possibility of observation of dry and moist convection in the atmospheric layer above the water surface is examined.  相似文献   

5.
The use of multitemporal space imagery in the study of vegetation change in a mountainous section of the Azerbaijan SSR is described. Maps depicting both the character and intensity of change are presented, and methods of their compilation described. Translated from: Geografiya i prirodnyye resursy, 1987, No. 4, pp. 174-176.  相似文献   

6.
System corrected multispectral imagery of the Central Afar region in Ethiopia provided by the ERTS-1 satellite was evaluated for the purposes of natural resource inventory under the headings of geology, vegetation, soils and land use. The methods and results of image interpretation are discussed in detail and the following general conclusions may be drawn. The ERTS-1 imagery provides a synoptic view of the region that is very nearly orthographic. A colour composite print of multispectral bands 4, 5 and 7 is superior to any of the individual black and white bands for natural resource interpretation. Exploratory soil, vegetation and land use maps and reconnaissance geological maps can be constructed rapidly. The small percentage of forest and agricultural land in this particular area enhances the geological value of the image. Satellite imagery is a valuable addition to the more conventional forms of aerial photography for agricultural studies provided that the study area covers at least 10 000 km2. Ground control was acquired between October 1972 and May 1973.  相似文献   

7.
The author surveys the use of remote sensing imagery in the study of mass exchange in glaciers, i.e., glacier dynamics resulting from phase changes in the water which they contain. A program of research now underway at the Institute of Geography (USSR Academy of Sciences) in conjunction with the “Priroda” Remote Sensing Center (Moscow) focuses on improving methods of data collection and mapping of glacier dynamics from space imagery, and particularly on identifying natural glacioclimatic zones believed to represent specific mass exchange conditions or regimes. The boundary of glacier nourishment separating areas of accumulation and ablation represents a key glacioclimatic indicator of mass exchange on satellite imagery and aerial photography. Translated from: Geodeziya i kartografiya, 1986, No. 5, pp. 26–31.  相似文献   

8.
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   

9.
The author outlines, in diagrammatic form, a procedure for the joint use of old maps (topographic, land survey, etc.) and current space imagery to compile maps of environmental change. The ancient maps reveal land use and physical conditions which serve as a benchmark for evaluation of subsequent change. Space imagery is useful both in updating the current state of the environment and providing a cartographic base for the preparation of final maps. Selected areas of Moscow Oblast are used as test sites. Translated from: Izvestiya vuzov, Geodeziya i aerofotos' yem-ka, 1985, No. 1, pp. 104-109.  相似文献   

10.
Results are presented of analysis of Landsat MSS imagery for the purpose of assessing damage to northern taiga and tundra vegetation caused by emissions generated by nonferrous metallurgy on northwest Russia's Kola Peninsula. Unlike earlier studies, the present project attempts to provide spatially comprehensive coverage of vegetation impacts, according to a standardized methodology for their assessment. A reduction in the number of feature classes identifiable upon a change from visual interpretation to automated classification based on spectral brightness values made it necessary to test alternative classification procedures (based on brightness ratios and the normalized vegetation index).  相似文献   

11.
本文主要简介秦岭金矿区一些与金矿化蚀变有关的植被景观异常及其遥感影像特征,并结合已知的生物学和植物反射光谱研究成果,对一些植物地球化学异常及有关的植物反射光谱异常的成因进行初步分析。  相似文献   

12.
The authors describe how remote sensing imagery may be employed in the zonation and mapping of the alluvial fans of the Fergana Basin, USSR. Settlement patterns depicted on these maps can then be analyzed by planners and civil defense personnel with a view toward minimizing risks posed by natural hazards endemic to alluvial fans: mudflows and other seismically triggered mass movements. Translated from: Geografiya i prirodnyye resursy, 1987, No. 3, pp. 50-55.  相似文献   

13.
A method is proposed for analyzing properties of solar radiation at the earth's surface based on satellite observations of cloud cover. It is shown that the amount of incident solar radiation is clearly governed by type of weather conditions and, more specifically, by the quantity and types of clouds. This affords a basis for predicting solar radiation receipt at the earth's surface. Translated by Edward Torrey, Alexandria, VA 22308 from: Vestnik Moskovskogo Universiteta, geografiya, 1989, No. 2, pp. 83–85.  相似文献   

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赣中红壤区TM图像的居民地信息自动提取专家模式研究   总被引:12,自引:1,他引:12  
从遥感信息分析入手,分析了抚州地区居民地在Landsat TM1 TM2 TM3 TM4 TM5 TM6 TM7各个波段上与其它背景地物的可分性。通过对各地物光谱曲线特征进行分析,利用居民地光谱特征与其它地物的差异性,建立条件表达式,即可把该区的居民地提取出来。通过验证,其点位精度达到81%,面积精度达到75%。该研究表明,通过简单模型的建立,可将以水泥顶房屋和瓦顶房屋为主的居民地提取出来。  相似文献   

16.
Feature classification maps derived from visual and automated methods of interpreting band-specific and composite imagery from the “Fragment” multispectral scanning system are compared in the study of vegetation and related features along the Gulf of Riga. The automated method, featuring a two-stage unsupervised/supervised classification algorithm developed at Moscow University (see MSRS, 1984, No. 3, pp. 255-261) provided for enhanced discrimination of wetland areas, farm land, and settlements, as well as for the elimination of extraneous components (especially the above) visually classified as deciduous forest. Translated from: Vestnilk Moskovskogo Universiteta, geografiya, 1988, No. 3, pp. 49-57 by Jay K. Mitchell, PlanEcon, Inc., Washington, DC 20005.  相似文献   

17.
The authors review recent developments in the USSR in the use of remote sensing imagery in the analysis, at the world-regional and local levels, of major relief elements (and structural elements manifest in relief) typical of mountainous country. Keys to their interpretation at a variety of scales are described. Case studies and detailed interpretation of imagery in the Soviet Far East and Central Asia (large-scale) and the Caucasus (intermediate-scale) provide for the identification of all morphostructural elements possible through traditional analysis, and in the latter case, for the first direct detection of transverse (cross-cutting) faults. Translated from: Geomorfologiya, 1988, No. 1, pp. 16-29.  相似文献   

18.
This paper provides a broad overview of current Soviet applications of remote sensing in the performance of forest inventories and related valuational studies, and in the production of derivative thematic maps—in particular, the photostatistical method of forest inventory based on interactive computer-assisted interpretation of satellite imagery and large-scale air photos. The ultimate future objective is the formation of a unified remote sensing-geographic information system for forest management and inventory purposes that will encompass the entire forested area of the country. Advances in the use of satellite imagery in the monitoring of forest fires, insect infestations, and rangeland deterioration have also been made since the late 1970s. Translated from: Geodeziya i kartografiya, 1986, No. 4, pp. 30–36.  相似文献   

19.
The authors present the results of experiments in the use of remote sensing imagery for construction of maps depicting human modification of nature. Four diverse areas within the USSR were selected as mapping sites, providing a broad range of environmental and land-use characteristics for investigation. Human impacts were most effectively mapped for two desert sites. The authors recommend combining satellite imagery with terrestrial spectrometric observations or color-infrared photography in investigations of environmental change in steppeland and forested territory. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1984, No. 6, pp. 11-18.  相似文献   

20.
Wetlands provide habitat for a wide variety of plant and animal species and contribute significantly to overall biodiversity in Ireland. Despite these known ecosystem services, the total wetland area in Ireland has reduced significantly over the past few decades leading to an ongoing need to protect such environments. The EU Habitats Directive (92/43/EEC) has recognised several wetlands types as “priority” habitats. This study concentrates on a subset of the priority habitats focussing on some groundwater dependent terrestrial ecosystems, (in particular calcareous fens and turloughs), as well as raised bogs. Monitoring these sites across the country by field visits is resource-intensive. Therefore, this study has evaluated remote sensing as a potentially cost-effective tool for monitoring the ecological health of the wetlands. Identification and presence of certain vegetation communities can indicate the condition of the wetland, which can be used for monitoring, for example, activities causing degradation or the progress of restoration attempts. The ecological composition of the wetlands has been analysed using open-source Sentinel-2 data. 10 bands of Sentinel-2 Level-2 data and 3 indices, Normalised Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI) and Normalised Difference Water Index (NDWI) were used to create vegetation maps of each wetland using Bagged Tree (BT) ensemble classifier and graph cut segmentation also known as MAP (maximum a posteriori) estimation. The proposed methodology has been validated on five raised bogs, five turloughs, and three fens at different times during 2017 and 2018 from which three case studies are presented. An overall classification accuracy up to 87% depending on the size of the vegetation community within each wetland has been achieved which suggests that the proposed method is appropriate for wetland health monitoring.  相似文献   

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