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491.
R. P. Vedeneyeva 《地理信息系统科学与遥感》2013,50(1):79-83
Measures to improve the effectiveness and informational content of general reference maps and other materials in atlases designed for the general public are outlined. Emphasis is placed upon (a) enhancing the readability and visual appeal of color “landscape” maps, providing a generalized, small-scale aerial view of the region(s) of interest–this through the application of principles of perception and colorimetry–and (b) developing larger-scale “reference” maps maximizing levels of graphic detail without jeopardizing ease of perception–this based on a careful study of general reference maps in atlases worldwide and broadly based testing of users with various levels of map reading skills. Translated from: Izvestiya vysshykh uchebnykh zavedeniy: Geodeziya i aerofotos'yemka, 1985, No. 6, pp. 111-115. 相似文献
492.
L. K. Zatonskiy 《地理信息系统科学与遥感》2013,50(2):148-153
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
493.
A paper devoted to the transformation of cartographic images based on nontraditional systems of scaling (travel time, transport effort, cost, etc.) describes the results of work to develop a more effective algorithm for such transformations, i.e., one which the authors claim provides for the more accurate determination of “transformed” line lengths than possible with earlier methods. Translated from: Izvestiya AN SSSR, seriya geograficheskaya, 1987, No. 4, pp. 105-111. 相似文献
494.
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
495.
Another paper in a series of articles on ecological-geographic mapping (see for example, Mapping Sciences and Remote Sensing, Vol. 31, No. 3, July-September 1994, pp. 185-220) focuses on outlining a concise typology of such maps and providing a brief history of their emergence during the 1970s and 1980s. A subsequent section is devoted to methods and technology used in the compilation of ecological-geographic maps, particularly the multiple variants of data organization, processing, and cartographic representation that can be factored into research design. Translated by Edward Torrey, Alexandria, VA 22308 from: Geografiya i prirodnyye resursy, 1995, No. 4, pp. 10-18. 相似文献
496.
Abstract A procedure for continental‐scale mapping of burned boreal forest at 10‐day intervals was developed for application to coarse resolution satellite imagery. The basis of the technique is a multiple logistic regression model parameterized using 1998 SPOT‐4 VEGETATION clear‐sky composites and training sites selected across Canada. Predictor features consisted of multi‐temporal change metrics based on reflectance and two vegetation indices, which were normalized to the trajectory of background vegetation to account for phenological variation. Spatial‐contextual tests applied to the logistic model output were developed to remove noise and increase the sensitivity of detection. The procedure was applied over Canada for the 1998‐2000 fire seasons and validated using fire surveys and burned area statistics from forest fire management agencies. The area of falsely mapped burns was found to be small (3.5% commission error over Canada), and most burns larger than 10 km2 were accurately detected and mapped (R2 = 0.90, P<0.005, n = 91 for burns in two provinces). Canada‐wide satellite burned area was similar, but consistently smaller by comparison to statistics compiled by the Canadian Interagency Forest Fire Centre (by 17% in 1998, 16% in 1999, and 3% in 2000). 相似文献
497.
Abstract This paper covers the development of a GIS instructional module centered on the reintroduction of the Mexican Gray Wolf in the Southwest, United States. This module is used in an undergraduate geography course on the United States. The paper also reports on how forty‐one students applied the module in trying to find an appropriate location to reintroduce the wolf. 相似文献
498.
Abstract Indo_Gangetic Plain (IGP) of India that stretched from the foothills of Himalayas near the Punjab State to the Gangetic delta in West Bengal State was known for highly fertile soil and favorable climatic condition for highest production of rice‐wheat. Appearance of soil salinity in large areas of IGP caused a major concern due to loss of productivity. The salt affected soils maps of India (NRSA 1997) showed vast areas of salt affected soils distributed along the Gangetic Plain covering the States of Haryana, Punjab, Uttar Pradesh, Bihar and West Bengal. In the analogue form, these maps contain voluminous data were difficult to handle without messing the whole dataset. An attempt was made to prepare a digitized database of salt affected soils to facilitate easy access, retrieval and map calculations required for reclamation and management of salt affected soil. The salt affected soils maps on 1:250, 000 scale were digitized for the States of Punjab, Haryana, Uttar Pradesh, Bihar and West Bengal using ILWIS. GIS. The Survey of India topomap was used for geo‐referencing and basemap preparation overlaying thematic layers for administrative and political boundaries, infrastructure, irrigation and drainage and settlements. The attribute data on physiography and the soil characteristics were stored in an attribute table and linked with the digitized polygons to prepare a relational database. Combining geo‐referenced (State) maps of Haryana, Punjab, Uttar Pradesh, Bihar and West Bengal using GIS, a composite map for Indo‐Gangetic plain was prepared. Four Agroclimatic regions (ACRs) and seventeen Agroclimatic zones (ACZs) were identified in the Indo‐Gangetic Plain (The Planning Commission of India) for planning and development of natural resources at regional level. The boundaries of ACZs and ACRs were delineated from the primary (master) database of IGP using ILWIS.GIS. The distribution of SAS polygons at regional and zonal level was delineated superimposing digitized boundaries of ACRs and ACZs over the master database of IGP. The state‐wise, region‐wise and zone‐wise extent of SAS was calculated. Soils were essentially saline at Lower‐ and Middle Gangetic Plain regions but highly variable and complex saline‐sodic in the Upper‐ and Trans‐Gangetic Plain regions. The area statistics showed that maximum SAS area occurred in ACR V (Upper Gangetic Plain) in Uttar Pradesh (UP) followed by ACR IV (Middle Gangetic Plain) in UP and Bihar, ACR III (Lower Gangetic Plain) in West Bengal and ACR VI (Trans‐Gangetic Plain) of Haryana and Punjab. Such database in digital format provides geo‐referenced, easy to access and retrievable, relational database comprising of thematic and attribute information of salt affected soils at state, regional and zonal level to facilitate overlay and map calculation of related data such as water quality, climatic, landform etc, useful for planning and decision making in reclamation and management of salt affected soils in IGP and other similar regions. 相似文献
499.
Salt affected soils occupy significant areas in western and central India manifested by the arid and semiarid climate, sandy/clayey soil texture, absence of natural drainage, and inadequate infrastructure and irrigation development. These soils are productive following reclamation and appropriate management. The National Remote Sensing Agency, Hyderabad (India) published state-wise maps of salt affected soils in India on 1:250,000 scale using a legend that includes physiography, soil characteristics, and the aerial extent of the mapping units. In the analogue form, voluminous data contained in such maps were difficult to handle by users of varied backgrounds. An attempt was made to prepare a computerized database of salt affected soils for easy access, retrieval, and manipulation of spatial and attribute data useful for management of salt affected soils. The salt affected soils maps were prepared, for Rajasthan, Gujarat, Madhya Pradesh, and Maharashtra states, overlaying digitized layers of SAS polygons and the Survey of India basemap using the ILWIS (Integrated Land and Water Information System) software. GIS was used to prepare a composite (master) database of western and central India that showed the extent and distribution of salt affected soils. A relational database was prepared combining the digitized polygons with soil characteristics such as nature and degree of salinity (presence of higher concentration of neutral salts and neutral soil reaction), sodicity (presence of higher concentration of basic salts and alkaline reaction) and ground coverage. The regional and zonal databases of salt affected soils were prepared at a suitable scale overlaying agro-climatic regions agro-climatic zones. Spatial relation of salt affected soils with physiography, climate, geology, and agro-eco-sub-regions were evaluated employing map calculations in GIS. Saline soils were prevalent in Gujarat, and Rajasthan while sodic soils were dominant in Maharashtra and Madhya Pradesh. These were distributed primarily in the arid (B) plain of Rajasthan, alluvial (A) and coastal (D) plains of Gujarat, and peninsular plain (F) of Maharashtra and Madhya Pradesh. It occupied 2,596,942 ha (78%) in the western (Rajasthan and Gujarat) and 733,608 ha (22%) in the central (Madhya Pradesh and Maharashtra) regions. The SAS occupied 3.3 million ha in the western and central region constituting 50% of the total salt affected soils in India. The saline and sodic soils occupied 2,069,285 ha (62%) and 1,261,266 ha (38%), respectively. 相似文献
500.
QuickBird satellite imagery acquired in June 2003 and September 2004 was evaluated for detecting the noxious weed spiny aster [Leucosyris spinosa (Benth.) Greene] on a south Texas, USA rangeland area. A subset of each of the satellite images representing a diversity of cover types was extracted and used as a study site. The satellite imagery had a spatial resolution of 2.8 m and contained 11-bit data. Unsupervised and supervised classification techniques were used to classify false colour composite (green, red, and near-infrared bands) images of the study site. Imagery acquired in June was superior to that obtained in September for distinguishing spiny aster infestations. This was attributed to differences in spiny aster phenology between the two dates. An unsupervised classification of the June image showed that spiny aster had producer's and user's accuracies of 90% and 93.1%, respectively, whereas a supervised classification of the June image had producer's and user's accuracies of 90% and 81.8%, respectively. These results indicate that high resolution satellite imagery coupled with image analysis techniques can be used successfully for detecting spiny aster infestations on rangelands. 相似文献