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301.
The use of intermediate-scale space imagery in the analysis of current and ancient deforestation is exemplified by a case study in the southwestern quarter of East Germany, an area heavily deforested as a result of mining and agricultural activities. More specifically a mosaic of 1:1,000,000-scale Landsat imagery was used to compile a series of maps (of modern landscapes, forests, land use), the comparison of which provided an inventory of the causes and extent of deforestation over the study area. This in turn permitted linkages between losses of forest cover and other environmental problems to be identified. Translated by Jay K. Mitchell, PlanEcon Inc., Washington, DC 20005 from: Geografiya i prirodnyye resursy, 1988, No. 1, pp. 165-173.  相似文献   
302.
An effort is made at developing a theory of map readability, defined as the process of the user's representation of the information of the map in his/her own mind. This can be estimated quantitatively by surrogate measures, which include the speed of map comprehension and accuracy of map interpretation. Levels of psychological representation of map information are incorporated to determine at what stage particular aspects of map knowledge are understood. Thus what readability entails, and the approaches used to measure it (what types of things are comprehended, how fast, and how accurately) will depend upon the level of representation. Translated from: Vestnik Leningradskogo Universiteta, seriya 7 [geologiya, geografiya], 1988, No. 1, pp. 32-37.  相似文献   
303.
Specific criteria used in the compilation of large-scale maps of erosion-prone areas are defined and evaluated for tracts of land representing a number of different agricultural cover types. Formulas are derived which facilitate the mapping of such areas based on such readily observable morphometric characteristics as slope length and steepness. Translated by Edward Torrey, Alexandria, VA 22308 from: Vestnik Moskovskogo Universiteta, geografiya, 1988, No. 5, pp. 25-31.  相似文献   
304.
Shortcomings in the representation of bottom relief features on topographic maps of the continental shelves are examined, with particular attention given to submarine ridges and related features, the symbolization of which on such maps has been entirely ineffective. Specific recommendations are given on the form and color of symbols which can be used in upgrading the graphic impact of maps depicting such relief forms. Translated by Edward Torrey, Alexandria, VA 22308 from: Geodeziya i kartografiya, 1989, No. 1, pp. 35–40.  相似文献   
305.
A Siberian geographer outlines the major aspects of a program to map the climatic and ecological state of ecosystems in the Lake Baykal region of southern East Siberia. A methodology for the classification of micro- and mesoclimates is outlined that is based on the structural characteristics of the underlying terrain surface, the character of air flows into the region, and extensive study of natural conditions in the region. Translated by Edward Torrey, Alexandria, Virginia from: Geografiya i prirodnyye resursy, 2000, No. 2, pp. 104-112.  相似文献   
306.
This paper explores how such characteristics as the polarization of reflected radiation, the angular characteristics of its reflectance, and its thermal properties can be used to supplement conventional remote sensing studies of the condition of the vegetation cover. One possible application is clarified by means of an experiment testing the relationship between the degree of polarization of radiation reflected from cultivated cotton fields and the condition of the crop in those fields. Empirical data demonstrate that changes in the geometric structure of (and reflectance from) fields occurs when cultivated plants are subjected to stress (disease or moisture deprivation). Translated by Edward Torrey, Alexandria, VA 22308 from: L. N. Vasil'yev, ed., Kosmicheskiye metody izucheniya biosfery [Remote Sensing Methods in the Study of the Biosphere]. Moscow: Nauka, 1990, pp. 77–82.  相似文献   
307.
The authors elaborate upon the “multiplicity principle” in remote sensing, i.e., the need for repeated imaging at a variety of scales, spatial resolutions, spectral bands, and times of imaging in order to attain the maximum information possible. They then explore the ways it can be applied in agricultural research, through two different image comparison and interpretation strategies. A detailed example is presented of the use of a multitemporal imaging strategy for the recognition of several agricultural crops from false color composite imagery. Translated by Edward Torrey, Alexandria, VA 22308 from: G. V. Dobrovol'skiy and V. L. Andronikov, eds., Aerokosmicheskiye metody v pochvo-vedenii 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. 47-55.  相似文献   
308.
The authors describe strategies for the utilization of digital image processing in the compilation of soil maps at scales of 1:1,000,000 and 1:25,000 for the trans-Volga region of Russia. Particular attention is devoted to an exploration of the effects of variations in soil humus content, texture, and degree of erosion upon spectral brightness coefficients. Results of the mapping demonstrate the promise of digital image processing in the differentiation of a number of chernozem soil subtypes. Translated by Edward Torrey, Alexandria, VA 22308 from: 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. 214–225.  相似文献   
309.
Two general approaches for compiling maps of components of the water-ice budget in regions of glacier nourishment are compared and the resulting maps are analyzed. The compilation of raw data is based on field measurements rather than remote sensing information. Translated by Edward Torrey, Alexandria, VA 22308 from: Materialy glyatsiologicheskikh issledovaniy, 1991, No. 72, pp. 94-102.  相似文献   
310.
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   
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