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1.
A multiscalar approach to mapping soil-vegetation regions from remote sensing imagery is outlined, using the West Siberian Lowland as a study area. At an initial stage small-scale space imagery is used to identify extensive soil-vegetation regions which extend across nearly the entire Lowland. Subsequent analysis focuses on identification and mapping of increasingly smaller units. The dominant criteria used for image interpretation and regionalization vary at each particular level of analysis, changing from vegetation structure and density at the smallest scales to soil “hydromorphism” (waterlogging) and topographic affiliations for intermediate- and large-scale units. Hydromorphic indicators are stressed as most important overall. Translated from: Distantsionnyye issledovaniya rel'yefa Sibiri, A. L. Yanshin and V. N. Sharapov, eds. Novosibirsk: Nauka, 1985, pp. 51-58.  相似文献   

2.
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   

3.
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   

4.
Industry concentrated in cities is a major source of geochemical pollution. It is suggested that this technogenic impact on the environment can be measured by techniques developed in geochemistry. The specific nature of the pollutants can be identified and their levels of concentration (mostly in the soil) can be measured against normal background values. This allows areas of pollution to be classified and mapped in terms of the composition and concentration of pollutants from industrial emissions. Translated from: Voprosy geografii, Vol. 120, 1983, pp. 55-67, by Robert K. Holz and Warren Hamill, University of Texas, Austin.  相似文献   

5.
The authors describe a procedure for the compilation of maps of the avalanche hazard in high-mountain regions of Afghanistan. The basic sources of information include space imagery (photographs and scanner imagery), weather station data, and other geographic information on relief, elevation, location of moisture sources, etc. The methodology features the compilation of series of increasingly more specific and informative maps and graphs regarding the avalanche hazard: terrain types, snow cover depth and seasonal extent, duration of snow cover and its elevational zonation, snow as a factor in avalanche formation, and summary map of avalanche hazard. Translated by Elliott B. Urdang, Providence, RI 02906 from: Materialy glyatsiologicheskikh issledovaniy, 1991, No. 71, pp. 86–93.  相似文献   

6.
7.
G. T. M. 《测量评论》2013,45(9):168-170
Abstract

In chain and traverse surveys areas are frequently required between chain lines and crooked fences. Commonly these areas are computed from offsets measured at equal intervals, which are so much the shorter according as the sinuosity is the greater. Most frequently Simson's Rules are employed for this computation; for (2m+1) offset ordinates, Simson's First Rule may be used; for (3m+1) ordinates, Simson's Second Rule. The First Rule assumes that the fence is made up of arcs of ordinary parabolae; the Second Rule, of arcs of cubic parabolae.  相似文献   

8.
The second of two reports on the use of space imagery in the interpretation of Antarctica's geologic structure applies interpretation procedures described in an earlier article (see Mapping Sciences and Remote Sensing, 1985, No. 1) to produce a geologic map of a portion of the Antarctic Peninsula. Features identified on space imagery and depicted on the map include: a deep pericratonnal fault zone, a Mesozoic fold belt interrupted by a complex system of faults, and ring or annular structures of volcanic origin. Translated from: Antarktika, AN SSSR Mezhduve-domstvennaya komissiya po izucheniyu Antarktiki, Doklady komissii [USSR Academy of Sciences Joint Commission on Antarctic Research, Commission Report], No. 24. Moscow, 1985, pp. 43-49.  相似文献   

9.
Spectral reflectances of artificial pastures are examined at various wavelengths and stages in the grazing/field work cycle to identify inadequately drained, marginally productive sites. Mesophytic pasture grasses and crops on well-drained sites are replaced by more hygrophytic species on poorly drained sites (each group with distinctive brightness values). This relationship, plus less significant spectral differences reflecting grazing intensity and soil moisture content at particular points in time, provided a methodological basis for the study. Poorly drained pastures are most reliably identified in the infrared and visible green portions of the spectrum during the middle of the grazing season. Translated from: Geografiya I prirodnyye resursy, 1988, No. 1, pp. 134-139.  相似文献   

10.
结合实际工作,探讨了外墙共用建筑面积和楼梯与电梯的分摊与计算等问题。  相似文献   

11.
《测量评论》2013,45(25):136-140
Abstract

In a previous article on this subject (Empire Survey Review, January 1937) the writer sought to show that for trigonometrical observations of vertical angles made near noon in the Tropics the coefficient of refraction depends chiefly on height above ground level in the case of stations sited within a few hundred feet above the general level of the ground surface. Indeed, the computed values of the coefficient K show a definite and appreciable increase with “h”, the height of the observing station above ground level; it is usually assumed that K decreases with increase in height above the Mean-Sea-Level surface. From analysis of the results obtained by varying h but holding the heights above Mean Sea Level fixed the writer came to the conclusion that the variations in K could only be due to abnormal values of dt/dh and d2t/dh2, “t” denoting the air temperature. Now it is generally recognized by meteorologists that abnormal lapse-rates of temperature do frequently occur in the lower air layers in the Tropics; but up to the present time no temperature soundings in Nigeria are available. Recently, however, the writer came across the results of the aerological soundings made by an expedition in East Africa during the year 1908. The results of many of the soundings were of no use for the purpose of this paper; many of the observations were not taken at or near noon, and in others counterlapses of temperature in the lower layers indicated that conditions were not normal. A set of observations taken at Mombasa between 10 and 11 a.m. were eventually chosen as offering an example of what might reasonably occur in the lower layers of the atmosphere.  相似文献   

12.
《测量评论》2013,45(17):165-169
Abstract

Brought up as we are in the British Empire in a world of difficult weights and measures, we come to regard them as inevitably complex and laborious, and only when we come into direct contact with professional and business men of foreign nations is it brought home to us how pathetically foolishwe are in sticking to systems of mensuration that have not resulted from deliberate thought but have evolved from the vagaries of mensuration in history. At the commencement of our instruction in arithmetic we are informed (to quote Workman's text-book) that “when we put down a list of the number of inches that make a foot, the number of feet that make a yard, and the number of yards that make a mile, we get what is called a Table of Long Measure. Similar tables are needed for other measures. The following tables must be learnt thoroughly by heart. They are all the measures which are really needed, though a great many more are in use and will be mentioned later.” Here follows, without a word of apology, a page of historical antiquities in the shape of our tables, each one a self-contained entity, seemingly priding itself on having no connexion whatever with any other.  相似文献   

13.
《测量评论》2013,45(73):119-130
Abstract

1. This new method of adjusting air photographs numerically to a uniform scale on a final map grid has already been described by the writert, where it concerns a large block-adjustment. The method to be described in this paper is the application of the same principle to the adjustment of photographic strips, covering narrow land areas and coastlines.  相似文献   

14.
G. M. T. 《测量评论》2013,45(23):49-53
Abstract

That admirable annual, The Surveyor (Ceylon), was generously forwarded to us some months ago. In this issue, vol. 2, no. 4, p. 93, there is given the solution of a question on resection in an examination paper. Since the solution appears rather laboured and the problem is interesting in itself and by no means valueless, it seems not out of place to attempt a simpler and more obvious answer.  相似文献   

15.
G. T. M. 《测量评论》2013,45(21):427-428
Abstract

For the sake of the junior reader we may repeat an old and simple investigation. Let us suppose that the paper on which a map is printed undergoes a regular expansion p in one direction, say the X direction, and another regular expansion q in the Y direction, perpendicular to the former; it is required to know the effect of these expansions on the area of any parcel on the map. Note that, so far as the mathematics are affected, X and Y are not necessarily parallel to the margins of the sheet; we shall take them here as axes of any rectangular coordinate system. The symbols p and q are regarded as ratios, so that 100p and 100p represent the percentage expansions; if the paper contracts instead of expanding, no more is necessary than to change the sign.  相似文献   

16.
The author, in a review of Ye. Ye. Shiryayev's book, Cartographic Presentation, Transformation, and Analysis of Geoinformation, addresses several issues in the automation of cartography—in particular what he perceives as a growing tendency to underestimate the importance of understanding the information being portrayed on maps. A formalistic (strictly quantitative) view of generalization that focuses on preservation or minimization of the loss of information on an initial map ignores the potential for the creation of new knowledge through the abstraction and elimination of information about lower-order systems. Salishchev criticizes Shiryayev's method of “raster digitizing” on such formalistic grounds, and because of its lack of visual quality and purported indiscriminate application within cartography. Shiryayev's reply to Salishchev's comments appears in the following paper of this issue. Translated from: Geodeziya i kartografiya, 1985, No. 11, pp. 59–61.  相似文献   

17.
A method is proposed for the calculation, based on the Goudriaan model, of estimates of various combinations of spectral radiance coefficients Pi which are optimal for interpretation of soil color and moisture, vegetation cover density, above-ground reserves of phytomass, and color and orientation of phytoelements. These estimates correspond rather closely with actual measurements obtained from the field. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1986, No. 4, pp. 75-79.  相似文献   

18.
《测量评论》2013,45(47):30-35
Abstract

In the Empire Survey Review for October 1938 (iv, 30, 480) a simple demonstration of the condition to be satisfied for conformal representation was given. This condition may be expressed by the equation w = f(z), where w and z are complex variables representing corresponding points in the w-plane and z-plane respectively, and f(z) is an analytic function of z.  相似文献   

19.
《测量评论》2013,45(58):152-153
Abstract

In vol. iv, nos. 29 and 30, of the E.S.R., there appeared an article by Mr. D. R. Hendrikz on the “Adjustment of the Secondary Triangulation of South Africa”. He shows that, in applying the Schols method of orthomorphic transmission to the adjustment of a secondary net to a primary triangle, the secondary sides suffer small displacements.  相似文献   

20.
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