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1.
In the present study, forest type classification using Landsat TM False Colour Composite (FCC) bands 2, 3, 4 has been evaluated for mapping highly heterogeneous forest environment of Western Ghats (Kerala). Visual interpretation of Landsat TM FCC has been carried out to identify bioclimatic vegetation types. For accuracy estimation maps prepared from 1∶15,000 scale black-and-white aerial photographs have been used as ground check data. For comparison aerial photomap classes have been aggregated to match with Landsat-TM-derived map. The classification accuracy of ten major bioclimatic and landcover types was estimated using systematic sampling procedure. The overall classification accuracy of the forest types for the study area was 88.33%.  相似文献   

2.
Soil maps have been prepared hitherto by conventional ground surveys and by using aerial photographs. In this paper, the use of LANDSAT data for preparation of small scale soil maps upto association of sub-group level has been discussed. Typical spectral curves for various soils and landuse categories were given based on the mean spectral levels for each LANDSAT band obtained from Multispectral Data Analysis System (M-DAS). Soil characterization using the multispectral data could be done by both image oriented and numerically oriented approaches. The small scale soil maps thus prepared by using the satellite data could be used for regional planning and as map base for further detailed surveys.  相似文献   

3.
Optimal land use map of Kanholi area, part of Nagpur district,Maharashtra have been prepared using Satellite imagery in 1:1000,000 and 1:250,000 and aerial photographs in 1:60,000 scale with adequate ground checks. The Satellite imagery proved valuable information about landscape characteristics, land use, hydrology and other environmental features. The aerial photographs were used to prepare comparatively large scale land resource association maps in scale 1:60,000 on geomorphology, landuse, soil hydrology. Soil irrigability, land irrigability and land capability maps are also attempted after interpreting soils information collected during field studies. The utility of this technique in preparation of optimal land use map with associated limitations due to scale have been discussed in the paper.  相似文献   

4.
Soils of part of Ukai‐kakarapar Command area, Gujarat (India) have been mapped at 1:25, 000 scale using aerial photographs of December 1977. It was observed that about 36.3% of the area was affected by soil salinity/alkalinity. The test area has been remapped using Salyut‐7 space photographs taken during Indo‐Soviet joint flight in April, 1984. The area affected by soil salinity/alkalinity was found to be substantially higher (80.3%). The earlier mapping using aerial photographs was done when the soil surface was compartively moist (December 1977) as compared to date of Salyut‐7 photography (April 1984), when the soil surface was likely to be devoid of moisture and the salts moved to the surface. To have easy comparision with the map prepared by using aerial photographs, Landsat TM data of December, 1985 was used in which 45.7% of the total area was mapped as salt affected. The extent of area delineated using Landsat TM was higher than that of 1977 but much lesser than the area delineated using Salyut‐7 (MKF‐6M) photographs. This indicated that the increase in the extent of salt affected area in the map prepared using the MKF‐6M photographs might be partly due to actual increase in the salinity/alkalinity and partly due to the seasonal affects. Among the various bands of MKF‐6M, band ‐4 was found to be the best for delineating the salt affected soils. The boundaries were sharper in the FCC and band No.4 of MKF‐6M than in the aerial photographs.  相似文献   

5.
Landsat images have been used in conjunction with topographical and geological information to prepare soil map of Mudhol taluk in Bijapur district, Karnataka state. The map has been compared with the reconnaisance map prepared by conventional method using 1:63,360 scale Survey of India toposheets. The study reveals that more accurate soil maps in terms of boundary delineation and composition of soil mapping units could be prepared by interpretation of Landsat images with adequate ground data. The method can thus be used in revising and improving many of the existing reconnaissance soil maps prepared by conventional method.  相似文献   

6.
本研究的目的是探讨利用遥感影像数据,对县级土壤调查资料进行地区级汇总的制图工作方法。我们依据的制图综合原则是:(1)以现有的土壤图为基础,充分尊重原图上的界线,主要以土层界线重新综合;(2)研究并搞清各种土壤分布规律和它们之间的组合规律,然后进行归并和区分;(3)参照卫星影像特征和判读标志,对某些明显与实地不符之处,以影像和实地调查资料进行修正,有些土壤类型以组合形式表达。本文对利用遥感数据进行制图综合的工作方法进行了详细描述,其中包括:制图单元的综合和比例尺的改变,底图的制作和利用卫星影像对综合后的土壤图进行编制等。研究结果表明,此种方法与常规方法比较,特别是对有一定物质和技术条件的单位(如省级),不仅在土壤调查中,而且在资源调查中皆可采用此种编图技术,收到节省人力、物力和时间的效果。  相似文献   

7.
Wasteland map (1∶100,000) of Rewasa catchment (Sikar district) has been prepared using aerial photographs and Landsat TM imagery. Thematic Mapper data were helpful in identifying the types of wastelands and details could be derived from the aerial photographs. The types of wastelands identified are sands, gullied land, salt affected areas, and barren rocky area. Depending upon the nature of wasteland, suitable rehabilitation measures like plantations, afforestation have been proposed.  相似文献   

8.
The use of remotely sensed data in the form of vertical aerial photographs has been in practice since several decades. Launching of Landsat satellites and their capability together multispectral scanner data afforded soil scientists enhanced capability for mapping soils. Technological advances in computer processing of Landsat MSS data coupled with ancillary information provided added advantages. Still difficulties exist in identifying the interference to vegetation and in segregation of narrowly defined soilscapes. Utility of statistical data, obtainable from computer analysis, and an aid in understanding the reflectance characteristics of various types of vegetation and soilscapes has been discussed in this paper. The final output obtained by computer processing compared with existing soil maps of the area registered more future prospects for utilisation of statistics in segregation of soilscapes and vegetation.  相似文献   

9.
The paper describes the details of a comparative study of geological interpretations carried out from Synthetic Aperture Radar (SAR) imagery, Landsat MSS (B & W) imagery and Aerial Photographs, covering 2100 sq km of area in Anantapur district of Andhra Pradesh. The area comprises Peninsular—Gneissic Complex and rocks of Dharwar and Cuddapah Super Groups beside the Quaternary alluvial deposits along the Penneru river and its tributaries. Geomorphologically the areas is represented by denudational, fluvial and structural landforms. The study indicates that the details of the geological and geomorphological maps prepared from SAR imagery and aerial photographs are comparable despite the smaller scale of SAR imagery while the same are not exhibited in Landsat imagery mainly due to its low resolution. Although broad lithological units are possible to be discriminated on SAR as well as aerial photographs, some of the finer rock types viz. gabbroic dykes could be discriminated from the delerite dykes in the SAR imagery due to their different surface roughness. Stereoscopic coverage and enhanced micro-relief of SAR imagery gives better geomorphological details in comparison to aerial photographs. A detailed study of lineaments has also been carried out which shows that in SAR imagery there is over-representation of short lineaments due to enhanced micro-relief and radarshadow effects across the look direction and under-representation of lineaments along the look direction. Landsat imagery is perhaps the best for demarcating lineaments of regional magnitude while aerial photographs are good for depicting shorter lineaments. However, certain lineaments seen in SAR imagery are often not continuously seen on aerial photographs.  相似文献   

10.
Remotely-sensed data products have got unique advantage over conventional data-gathering techniques in the study of urban morphology. The physical parameters like built-up area density, street pattern, population density, urban structure as well as functional characteristics which can be derived from land use/land cover map, are clearly visible on aerial data products. This technique provides synoptic view of the area which makes the study comprehensive and uniform. Sequential aerial photographs and satellite imagery help in studying the growth of urban area and temporal changes in urban structure. These informations are very useful in the planning of city extension. Here an attempt has been made to study the urban morphology of Saharanpur city by using panchromatic aerial photographs on scale 1∶10,000, IRS-1B LISS II geocoded imagery on 1∶50,000 scale and photo-maps on 1∶4000 scale, and the results are very encouraging.  相似文献   

11.
This paper presents a case study of the utility of Landsat MSS imagery for soil resoruces mapping in Silent Valley and its environs covering about 33,000 sq. km. area. A collective approach involving monoscopic visual interpretation of Landsat imagery in conjunction with the lithological and topographical information supported by limited field check has been followed to prepare a soil map on 1:250,000 scale showing sub-groups/association of sub-groups. Future prospect of using spaceborne data for soil mapping has also been discussed.  相似文献   

12.
A section of an Apollo space photo relating to the Magadh area of Bihar state was monoscopically interpreted resulting in six delineations based upon tone and texture variations. Small scale aerial photographs were used for the preparation of soil map of a part of the area using a systematic air photointerpretation procedure; this served as a basis for defining the soil composition of four out of the six space photo analytical units. In respect of the remaining two units-soil information was obtained by reference to an existing small seale soil map of Bihar State. The data thus obtained have been used to prepare a small scale soil map of the selected section of the Apollo space photo. The soil map of the part of the space photo area that is based on support ph: to-interpretation has been found to have the quality and accuracy expected of very small scale soil maps.  相似文献   

13.
The map showing the extent of salt affected and sand dune soils was prepared at 1:50,000 scale using Landsat TM data for March 1987 and compared with the soil map of Kapurthala district based on 1965 aerial photographs and semi detailed survey of the district during 1975–76. The study revealed that in a span of 22 years (1965 to 1986) the area of sand dunes decreased from 22.7 per cent to 2.3 per cent and that of salt affected soils from 20.95 per cent to 4.38 per cent respectively as a consequence of reclamation of salt affected soils and clearing and levelling of sand dunes. Salt affected soils after reclamation have been brought under paddy-wheat rotation. Whereas sand dunes after clearing and levelling, have been brought under wheat or wheat -rice/fodder/oilseed crops.  相似文献   

14.
The use of Landsat imagery at 1:1 M and 1:250,000 and aerial photos on 1:65,000 and 1:20,000 scale have been used to study landuse. It has been possible to achieve identification using Landsat imagery up to utility level ( level 1 and II ) and with the aerial photographs further subdivisions of utility into management and identification (level III and IV) .  相似文献   

15.
Soil and land resources inventory and their proper utilisation is important for scientific and economic planning. Advances in scientific technology provided more promising base for abstracting information of soil and land resources for evaluating their potentials and efficient utilisation. Aerial photograph since 1940’s and landsat data from 1970’s opened new vistas of knowledge in such a task and proved to be very promising. Extra information with increased accuracy that is possible through these techniques accentuated their wider applications. The merits and demerits of these two techniques over the conventional approach have been discussed. A case study in an area of Mahaboobnagar district, Andhra Pradesh is presented in this paper. Aerial photographs of 1∶20,000 scale and landsat data of 4, 5 and 7 bands and alse Colour Composite in 1:250000 scales have been used for this study. The data acquired through conventional field work at Rapid Reconnaissance survey level is taken as a base for comparison. The study revealed the superiority of Aerial photograph over other techniques whereas visual interpretation of landsat products yielded additional information over conventional method. The time and cost efficiency was found to be in the order of 1∶3∶7 and 1∶6∶18 respectively for landsat, aerial photograph and conventional field work.  相似文献   

16.
大比例尺地形图数据库的更新是一项长期的重要任务。本文分析了1∶2000地形图数据库快速更新的难点,提出了一种航空摄影与卫星遥感、区域更新与要素更新相结合的大比例尺地形图数据库半自动快速更新方法。采用变化检测方法从更新前后卫星遥感影像中提取变化区域和变化要素,然后分别采用面向区域和面向要素的方法从高分辨率航空影像上测量变化地物,最后通过半自动空间实体匹配的方法建立现状库与历史库中要素的回溯关联,从而实现地形图数据库的半自动增量式快速更新。利用该方法对中山市东区的1∶2000地形图进行了更新试验。试验结果表明,引入卫星影像进行自动变化检测后,在航空影像上分区域和要素两种模式采集更新城市大比例尺地形图数据库,效率比传统方法提高25%。  相似文献   

17.
本文论述了空间实验室测量相机(MC)拍摄的彩色红外立体像对在中比例尺地形制图、正射影像地图以及土地资源调查中的应用可能性,给出1:10万和1:20万比例尺的制图例证,表明平面位置和高程精度能满足1:10万比例尺地形图规范要求;1:10万比例尺影像图可以满足专题制图精度要求。 应用数字图像处理技术,将二种来源(MC,MSS)的遥感数据做数字匹配,并进行信息提取、组合、增强和分类等处理,其结果与原始图像比较表明有独特的优越性,与MSS原始数据相比,图像的空间分辨率明显提高,各种类型界线更分明,可分辨类目增多;而与MC原始图像相比,其光谱特性获得改善且能保持原有的空间分辨率。土地利用类型解释精度与MSS和MC原始图像比较分别提高7—20%左右。  相似文献   

18.
In this study the analysis of Saharanpur region has been done at Roorkee University for the development and growth of the region, using Landsat Imagery of November, 1972 (Bands 5 and 7) after enlarging it to a Scale of 1:250,000. Land utilization map (by visual interpretaion) was prepared, on the base map obtained from 250,000 toposheet, interpreting three main element of the image i.e. tone, texture and pattern-Sample verification of the landuses obtained was done by the interpretation of 1:10,000 scale photos for plains and 1:60,000 scale photographs for hilly area and found quite reasonable. Some of the information about population and the distribution of population according to the sizes of the settlements are found by the census report. The road work information is obtained from the toposheet and aerial photographs. After getting this information, hierarchy of settlements, land utilizaton onward settlement, population of the settlements, road conncetions between settlements and the size of the settlements are determined. The strategy for development of Growth centres is thought out and the facilities of these Growth centres are proposed. It has been found that the remote sensing technique gives a hierarchy by which optimum location of growth centres in the region is comparatively very easy, time saving and economical.  相似文献   

19.
The paper summarises a part of the results of an on-going project for quantifying the land use changes in Bhavani basin (Geographic co-ordinates N lat 10°55′ - 11°45′,E Long. 76°30′ - 77°45′). Landsat and aerial data have been used in monitoring the dynamic changes in land use patterns. Visually interpreted Landsat MSS data of two different dates in conjunction with the historic data acquired from the Survey of India topographic maps and field data were used in this investigation. Also land use changes over two test-sites in the basin were studied using aerial photographs. During the study, it has been observed that a direct correlation exists between the rainfall and the area irrigated. The repetitive coverage of the satellite data are found to be quite remarkable, especially the 1:250,000 False Colour Composites (FCC) in assessing rapidly the temporal land use changes of a region at a cheaper cost.  相似文献   

20.
本文讨论了以热带森林植被为主体的再生资源的面积动态变化监测。研究中包括两个部分。首先,我们利用多时相遥感图像对大面积的西双版纳州进行地类判读,系统地分析了森林植被的动态变化。其次,利用Landsat MSS和TM数据对自然保护区的动态变化进行了包含无监督分类和归一化差值植被指数分析的数字图像处理,变化分类也相当符合实际。总的实验结果表明,这种监测方法是很有效的,可在再生资源监测中特别是在森林植被监测中加以推广应用。  相似文献   

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