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1.
Sodicland reclamation in the Indo-Gangetic plains is being done on a large scale in the states of Uttar Pradesh, Punjab and Haryana in India. However, in certain areas, the reclamation has been reported to be unsustainable and the soils are reverting back to sodicity condition. A study was conducted in one of the reclamation sites of Etawah district for sustainability assessment of sodic land reclamation using remote sensing, Geographic Information system (GIS) and ancillary ground information. Multitemporal satellite data were used for delineation of reclaimed sodiclands and reverted sodic land. Field survey was conducted to find out the various causative factors. Groundwater level information and detailed field survey data were analysed in GIS environment. Results showed that in the reclamation site covering 3,905 ha. in 57 villages of the district, about 27 per cent of reclaimed lands were reverted to sodicity. High water table condition, improper drainage, nearness to canal (within 500 m), and hard pan in the sub-soil were found to be the reasons for unsustainability of reclamation.  相似文献   

2.
LANDSAT-TM has been evaluated for forest cover type and landuse classification in subtropical forests of Kumaon Himalaya (U.P.) Comparative evaluation of false colour composite generated by using various band combinations has been made. Digital image processing of Landsat-TM data on VIPS-32 RRSSC computer system has been carried out to stratify vegetation types. Conventional band combination in false colour composite is Bands 2, 3 and 4 in Red/Green/Blue sequence of Landsat TM for landuse classification. The present study however suggests that false colour combination using Landsat TM bands viz., 4, 5 and 3 in Red/Green/Blue sequence is the most suitable for visual interpretation of various forest cover types and landuse classes. It is felt that to extract full information from increased spatial and spectral resolution of Landsat TM, it is necessary to process the data digitally to classify land cover features like vegetation. Supervised classification using maximum likelihood algorithm has been attemped to stratify the forest vegetation. Only four bands are sufficient enough to classify vegetaton types. These bands are 2,3,4 and 5. The classification results were smoothed digitaly to increase the readiability of the map. Finally, the classification carred out using digital technique were evaluated using systematic sampling design. It is observed that forest cover type mapping can be achieved upto 80% overall mapping accuracy. Monospecies stand Chirpine can be mapped in two density classes viz., dense pine (<40%) with more than 90% accuracy. Poor accuracy (66%) was observed while mapping pine medium dense areas. The digital smoothening reduced the overall mapping accuracy. Conclusively, Landsat-TM can be used as operatonal sensor for forest cover type mapping even in complex landuse-terrain of Kumaon Himalaya (U.P.)  相似文献   

3.
动态矿区DEM生成方法及其在土地复垦中的应用研究   总被引:2,自引:1,他引:1  
首先根据我国矿区土地复垦工作中存在的不足,通过研究提出"动态土地复垦"的概念,并确定了动态土地复垦方案制定的数据基础——动态矿区数字高程模型。动态矿区数字高程模型应该包含煤矿生产对地表的累积影响结果数据和地表的原始地形信息,开采沉陷预计结果可以提供前者,地面测量可以提供后者,经过数据处理可以按时间间隔生成描述塌陷区的一系列数字高程模型(DEM)(准动态),然后运用DEM的空间分析技术提取塌陷区在不同时间段的土地破坏类型、范围和位置数据,并根据这些数据进行动态土地复垦方案决策数据的提取,经实例验证该方法可行。  相似文献   

4.
设计了一种较系统的地貌彩色晕渲图设色方案,根据任意高程范围内的DEM数据,自动采用相应模式,生成了满足专业制图标准的彩色晕渲图。  相似文献   

5.
Abstract

Spaceborne multispectral measurements have been found very useful tool in delineating soilscape boundaries. The Indian Remote Sensing Satellite (IRS 1B) Linear Imaging Self‐scanning Sensor (LISS‐II) data in the form of false colour composite (FCC) prints at 1:50,000 scale covering part of a complex terrain ‐ hard rock intermixed with the alluvium, were interpreted visually for mapping soil resources. The physiography and lithology of the terrain have been found to have a direct bearing on the occurrence of soils. The image elements which are the reflection of surface drainage, land use/land cover, wetness, etc have been helpful in segregating the broad physiographic units into their components. These sub‐divisions were ultimately found to be associated with the characteristic soils. The methodology and results are discussed in detail.  相似文献   

6.
The area around Khodana, Bhiwani district, Haryana forms a part of the semi-arid region of western India. As vegetation is sparse and mainly xerophytic, photointerpretation technology was effectively utilised in bringing out the broad geology and structural pattern of the mature Precambrian terrain, which were ground-checked and correlated with the results of detailed integrated surveys carried out for base metal sulphide mineralisation in the area. A number of shear/fault zones, sub-parallel to the formational contacts and the regional fold axes, could be recognised in aerial photographs and on ground checking, were found to be intensely limonitised. The possibility of direct application of the pyrite-pyrthotite, encountered in drilling through shear zones, in landuse planning has been discussed. Discrete use of the quartzites as road ballasts, building stone and bund material, use of clay-rich pockets within pasture lands or micro-depressions in the surrounding terrain for locally-constructed brick kilns and ochreous material as pigments are some other uses of finite land resources of Haryana State.  相似文献   

7.
Based on the visual interpretation of satellite (Landsat) false colour composite imagery, the entire Haryana State is divided into eleven landform units. Seven major landform units are studied in details with respect to water table fluctuation, ground water quantum and draft. The studies reveal that usable recharge and draft per unit area are maximum in case of area of water seepage and periodic flooding followed by Yamuna and Ghaggar flood plain and upper alluvial plains with occasional sand dunes. The minimum recharge and draft are observed in case of dune areas.  相似文献   

8.
Salinity is creating great problems in the Yamuna Alluvial Plain. State Government is taking steps for reclaiming these lands to increase agricultural production. Impeded drainage, excess canal irrigation, topography parent material, shallow depth and bad quality of ground water are the main factors which are responsible for the genesis of saline soils in the alluvial plains of Haryana. On the arial photographs tonal differences on account of salt concentration in the soil are clearly seen. These differences are aslo associated with physiography and soil conditions which can be easily delineated. The information thus; collected can be used for reclamation of saline soils.  相似文献   

9.
Identification of fractures/lineaments and hydrogeomorphic units is prerequisite for undertaking ground water exploration and development in any terrain. Use of satellite remote sensing techniques coupled with aerial photo-interpretation greatly aid in planning ground water exploration, and pin pointing well sites In this study, airborne and space borne data was used for qualitative evaluation of ground water resources and a critical appraisal of such study in combination with hydrogeological and hydrogeophysical techniques for ground water exploration and development in Keonjhar district of Orissa. The study area has been divided into various geomorphic units based on visual interpretation of Landsat (TM) false colour composite on. 1:2,50,000 scale and the ground water potential of each of the units is qualitatively assessed. Digital image processing techniques such as principal component analysis and brightness index were used for generating classified outputs. The features like valley fills, pediments ete appeared clearly on the classified image. Directional filtering brought out minor fractures/lineaments crisply. The study has revealed the significance of different hydrogeomorptuc units and lineaments in Controlling ground water potential of the area. The findings were corroborated by resalts of drilling and resistivity soundings.  相似文献   

10.
Thar desert spreads in western part of Rajasthan, northern part of Gujarat, and some parts of Punjab and Haryana. The terrain is dominated by slightly sloping plains, broken by some dunes and low barren hills. The area is characterized by low average annual rainfall which is erratic in distribution and intensity. Drought will remain a major hindrance for agricultural production in Thar desert. Due to water stress condition, many watershed based development activities has been adopted by government and non-government organizations for the growth and sustainable development of this region. The need of this hour is preparation of a national level watershed atlas of 1:50,000 scale because majority of thematic maps are being produced presently on same or 1:10,000 scale. The manual delineation of watershed boundary in flat terrain based on topographic map will be time consuming and less accurate in the absence of prominent contour lines. Automated approach for watershed delineation using Digital Elevation Model (DEM) along a suitable algorithm has the advantage because the output is not only less time consuming but also independent from human decisions. Hence, a case study has been carried out in Churu sub-basin part of Indus basin which is located in Thar desert region. Depression less DEM with different spatial resolutions was used as input in hydrology tool of ArcGIS spatial analyst function for characterization of watersheds. The Churu sub-basin has been divided into various numbers of watersheds with an average size of 600 km2. These watershed boundaries have been validated with respect to high resolution satellite imageries (IRS P6 LISS IV), Survey of India toposheets, ancillary data and limited field checks.  相似文献   

11.
Progress in the Development of a High Performance Airborne Digital Sensor   总被引:1,自引:0,他引:1  
Joint development work by LH Systems and Deutsches Zentrum für Luft- und Raumfahrt (German Aerospace Center) has produced encouraging results using forward, nadir and backward looking linear arrays on the focal plane to provide panchromatic imagery and geometric information, supplemented by further arrays to acquire multispectral imagery suitable for both high precision photogrammetric mapping and image processing for interpretative purposes. The geometric characteristics of line scanner imagery necessitate line-by-line rectification for aircraft tilts and shifts. Satisfactory execution of this process is enhanced by using supplementary data from high performance, on-board GPS and inertial measurement systems. Similarly, high demands are placed on other sub-systems, such as the camera mount, lens, electronics and storage technology. In addition to rectification for aircraft tilts and shifts, rectification for terrain characteristics is also required in order to generate colour and false colour composite images, since the various multispectral arrays are in different places on the focal plane. The special geometry affects triangulation. Thereafter, the imagery can be processed using existing software packages from both photogrammetry and remote sensing.
The concept has been demonstrated in several successful test flights and the production model is scheduled for market introduction at the ISPRS Congress in July 2000. The imagery from the new sensor will fulfil many market requirements between the highest resolution film imagery (<0.1 m) and high resolution space imagery (1m to 10 m). The sensor's unique blend of multispectral information with high quality geometric information will give rise to numerous new applications.  相似文献   

12.
The AP190 analytical stereoplotter has been employed for two research projects concerned with the urban and suburban environment. In the first project, the suitability of the AP190 was assessed for comparing height readings between stereomodels of colour diapositives and colour paper prints, for collecting height data for a digital terrain model and for producing a land use map using a stereopair of part of Edinburgh under well controlled conditions. The second project dealt with the densification of minor control points by means of the BLOKK aerial triangulation package, followed by the digital mapping of a suburban area planned for land readjustment in Bangkok.  相似文献   

13.
施显健  任超  周吕  黄远林  梁月吉  朱子林 《测绘科学》2021,46(2):146-151,164
为了更好地监测和掌握深圳填海区地铁工程结束后地铁沿线的地面沉降情况,该文利用TS-InSAR技术和20景2017年8月15日—2019年3月14日的Sentinel-1A SAR数据,借助POD精密定轨星历和ASTER GDEM V2分别去除轨道误差和地形相位,反演了深圳填海区2017—2019年地表沉降时间序列,并在此基础上重点分析了填海区地铁沿线地面沉降的时空演变规律以及地面沉降成因。结果显示,填海区各地铁沿线的地面沉降特征较为明显,最大沉降速率为-17.52 mm/a。其中,宝安中心、前海湾、深圳湾区段地铁沿线的地面沉降趋势较为严重,其地面沉降呈现逐渐增强和扩散趋势。  相似文献   

14.
LiDAR系统测量成果精度检测   总被引:1,自引:0,他引:1  
王晓辉  胡伍生  刘行波 《测绘工程》2007,16(3):67-69,73
LiDAR技术可直接获取三维地表地形数据,具有传统摄影测量方法和地面常规测量技术无法比拟的优越性,已成为获取高时空分辨率地球空间信息的一种全新技术手段,引起了国内外学者的极大关注。LiDAR技术在地形测绘、环境监测、三维城市建模等诸多领域具有广阔的发展前景和应用需求。文中采用试验数据,检测并评价Li-DAR系统生成的DEM、DOM精度,探讨其在基础测绘中的应用可能性,具有现实意义。  相似文献   

15.
马静谨  李强 《测绘工程》2007,16(2):27-29,32
对于大规模地形而言,地形网格的实时动态绘制速度和质量一直是人们关注的重点。地形漫游在仿真、模拟、虚拟现实、游戏等领域都有广泛的应用。该文在研究多种层次算法的基础上,采用一种地形瓦片重组数据结构的方法实现实时高帧率的绘制大规模地形。分析了地形场景数据管理与实时调度,视相关多层次细节模型与可见性判断以及分层数据组织和瓦片数据绘制等关键问题,并给出了相应的解决方法,改进了视景体裁切重组地形数据的方法。实验结果表明该方法在保持地形逼真的前提下,有很好的绘制网格帧率和实时动态交互效果。  相似文献   

16.
随着无人机与新型航拍技术的发展,无人机倾斜摄影技术在大范围地形数据采集过程中发挥了重要作用,三维测绘相关研究得到了极大的促进。而针对水利行业所需的水上地形与水下地形一体化生产过程的研究相对较少。本文布设统一控制点,采用固定翼无人机倾斜摄影测量技术进行水上地形测绘,应用RTK配合测深仪在船上进行水下河道三维地形数据采集,对于涉河建筑物采用BIM软件进行参数化建模。最后,针对水上地形数据,水下河道地形数据及建筑物三维模型进行融合处理,得到水上水下一体化三维河道场景,搭建Cesium平台进行三维展示。其研究成果可为水上水下一体化测绘与可视化提供技术帮助,有助于推进智慧水利的应用发展。  相似文献   

17.
The accuracy of topographic correction of Landsat data based on a Digital Surface Model (DSM) depends on the quality, scale and spatial resolution of the DSM data used and the co-registration between the DSM and the satellite image. A physics-based bidirectional reflectance distribution function (BRDF) and atmospheric correction model in conjunction with a 1-second DSM was used to conduct the analysis in this paper. The results show that for the examples used from Australia, the 1-second DSM, can provide an effective product for this task. However, it was found that some remaining artefacts in the DSM data, originally due to radar shadow, can still cause significant local errors in the correction. Where they occur, false shadows and over-corrected surface reflectance factors can be observed. More generally, accurate co-registration between satellite images and DSM data was found to be critical for effective correction. Mis-registration by one or two pixels could lead to large errors of retrieved surface reflectance factors in gully and ridge areas. Using low-resolution DSM data in conjunction with high-resolution satellite images will also fail to correct significant terrain components where they occur at the finer scales of the satellite images. DSM resolution appropriate to the resolution of satellite image and the roughness of the terrain is needed for effective results, and the rougher the terrain, the more critical will be the accurate registration.  相似文献   

18.
地景模型的简化与快速绘制方法研究   总被引:2,自引:0,他引:2  
在分析地景模型数据特点的基础上,提出了地景模型简化的判决准则,并根据该则提出了基于视点的区域数据抽取与简化方法以及基于法矢量的细节模型简化方法。实验结果表明,使用该方法数据压缩量大,绘制速度快,且逼真度无明显变化。  相似文献   

19.
针对PDA硬件配置低,运算能力差等弱点,本文提出了一种基于PDA的三维地形实时绘制的优化方法。在地形数据装载到PDA之前,我们对其进行预处理:顶点坐标转换,计算法向量等并将数据根据PDA的显示特点进行分块;地形数据实时绘制过程中,我们采用假光照,背面消隐,多索引机制等方法进行优化处理。最后,在PDA上完成了实验论证工作,实验表明经过该方法处理后较明显的降低了地形绘制的响应时间,并给出了测试数据。  相似文献   

20.
李禹  计科峰  吴永辉  粟毅 《遥感学报》2009,13(2):232-237
该文引入差分盒维法来计算高分辨率SAR图像车辆目标的一种新的鉴别特征,即间隙度特征,可以用来定量评估车俩目标感兴趣区域内像素幅度的不规则程度和间隙尺寸,以此消除杂波虚警.基丁散射中心理论分析了车辆目标和自然地物后向散射强度分布的差异性,并从理论上推导出间隙度特征具有对相干斑噪声不敏感的特点,由此构成了SAR图像车辆目标鉴别处理的一个尺度不变特征.采用MSTAR车辆目标数据和背景杂波数据检验了所提特征的鉴别性能,并与Hausdorff维数的鉴别性能做了比较,结果显示间隙度特征具有较好的鉴别性能,可以去除大部分的自然地物虚警和非车辆类人造目标干扰,鉴别虚警率较低.  相似文献   

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