Groundwater prospective zones in basaltic terrain using remote sensing

Journal of the Indian Society of Remote Sensing - The study aims at investigating the relative role of landforms and lineaments as an integrated unit for the assessment of groundwater availability...     

利用OpenStreetMap数据进行高空间分辨率遥感影像分类

针对高分辨率遥感影像分类样本标注困难的问题,提出了一种利用OpenStreetMap （OSM）数据自动获取标注样本的方法。与现有的利用OSM数据进行分类的方法不同,该方法加入了空间特征以弥补单独使用光谱特征分类的不足。首先,基于OSM数据提供的地物类别和位置信息进行样本标注,为了降低OSM数据中少量错误信息对分类结果的影响,采用聚类分析的方法对样本进行提纯;其次,使用形态学轮廓来提取影像的结构特征,挖掘高分辨率遥感影像丰富的空间信息,与光谱特征相叠加并输入分类器进行分类。试验证明,本文提出的方法能够有效避免人工样本标注所需要的人力物力;同时,联合影像的光谱空间特征能够更好地描述地物特性,得到较高的分类精度。     

月球遥感制图回顾与展望

对月球探测任务、月球遥感制图技术与产品进行综述。从1958年开始,全世界已开展126次(其中70次成功)月球探测工程任务,其中月球遥感制图是其必需的基础性工作。由于月球环境的特殊性,其遥感制图技术与对地观测制图相比具有很大的挑战和更大的难度。目前,中国嫦娥二号轨道器获取的7 m分辨率立体影像是覆盖全月球分辨率最高的立体影像数据,美国月球侦察轨道器LRO任务的激光雷达高度计LOLA数据是精度和密度最高的激光测高数据,LRO NAC影像的分辨率最高(0.5—2 m)但未覆盖全球。在各个探测任务中,基于月球遥感数据和摄影测量技术,已经制作了大量的全球及区域的影像拼图、正射影像图和数字高程模型等制图产品。对月球遥感制图技术发展进行展望,探讨了利用国际多探测任务数据建立新一代控制网和进行精细制图的必要性及技术思路。     

Flood inundation modeling using MIKE FLOOD and remote sensing data

A coupled 1D-2D hydrodynamic model, MIKE FLOOD was used to simulate the flood inundation extent and flooding depth in the delta region of Mahanadi River basin in India. Initially, the 1D model MIKE 11 was calibrated using river water level and discharge data of various gauging sites for the monsoon period (June to October) of the year 2002. Subsequently, the calibrated set up was validated using both discharge and water level data for the same period of the year 2001. The performance of calibration and validation results of MIKE 11 were evaluated using different performance indices. A bathymetry of the study area with a spatial resolution of 90m was prepared from SRTM DEM and provided as an input to the 2D model, MIKE 21. MIKE 11 and MIKE 21 models were then coupled using lateral links to form the MIKE FLOOD model set up for simulating the two dimensional flood inundations in the study area. Flood inundation is simulated for the year 2001 and the maximum flood inundation extent simulated by the model was compared with the corresponding actual inundated area obtained from IRS-1D WiFS image.     

Estimating canopy water content using hyperspectral remote sensing data

Hyperspectral remote sensing has demonstrated great potential for accurate retrieval of canopy water content (CWC). This CWC is defined by the product of the leaf equivalent water thickness (EWT) and the leaf area index (LAI). In this paper, in particular the spectral information provided by the canopy water absorption feature at 970 nm for estimating and predicting CWC was studied using a modelling approach and in situ spectroradiometric measurements. The relationship of the first derivative at the right slope of the 970 nm water absorption feature with CWC was investigated with the PROSAIL radiative transfer model and tested for field spectroradiometer measurements on two test sites. The first site was a heterogeneous floodplain with natural vegetation like grasses and various shrubs. The second site was an extensively grazed fen meadow.     

Web service for biodiversity estimation using remote sensing data

Abstract

This paper presents a technique for the assessment and mapping of land biodiversity by using remote sensing data. The proposed approach uses a fuzzy model that encapsulates different ecological factors influencing biodiversity. We implemented our approach as a web service for the Pre-Black Sea region of the Ukraine.     

Normalisation of multi-date digital remote sensing data using scene statistics

Some of the studies involving digital temporal data require normalisation. Many of the normalisation methods need information on prevailing atmospheric conditions, sensor-related details etc., whereas some other methods use only the information which are within the data set. A study was conducted in Kudremukh Iron Ore miningsite, Karnataka using multi-date data from Landsat MSS of 1976 and 1985. A normalisation method using only the scene statistics of the images is suggested which brings the multi-date data at par. This method is compared with some of the other methods which use only the information content of the data set. Comparison of these methods was made by scattergrams, distance measure etc. By generating scattergrams for various combinations of non-normalised and normalised images, different methods were compared. Based on ground information, some changed and unchanged classes were noted on the various normalised and original images. Using the distance measure for classes in different images, the normalisation procedures were compared. The proposed method turned out to be the best among the methods compared.     

植被光能利用率遥感估算

光能利用率表征植被通过光合作用将所截获/吸收的能量转化为有机碳的效率,是遥感估算植被生产力的关键参数.由于植被分布和气候环境的综合影响,光能利用率表现出显著的空间异质性和时间动态性,光能利用率的不确定性成为后续生产力模型估算精度不高的重要原因.本文以Fluxnet全球通量站点数据和MODIS LAI/fPAR产品为数据...     

Reflectance characteristics of rocks in geological remote sensing

Surface and laboratory measured reflectance data of various rock types were analysed for the possible correlation with Landsat MSS response using statistical methods. It is found that band 6(0.7–0.8 μm) in field and satellite and band 7(0.8–1.1) in field and laboratory data have maximum correlation coefficient.     

Predicting grain protein content of winter wheat using remote sensing data based on nitrogen status and water stress

Advanced site-specific knowledge of grain protein content of winter wheat from remote sensing data would provide opportunities to manage grain harvest differently, and to maximize output by adjusting input in fields. In this study, remote sensing data were utilized to predict grain protein content. Firstly, the leaf nitrogen content at winter wheat anthesis stage was proved to be significantly correlated with grain protein content (R² = 0.36), and spectral indices significantly correlated to leaf nitrogen content at anthesis stage were potential indicators for grain protein content. The vegetation index, VI_green, derived from the canopy spectral reflectance at green and red bands, was significantly correlated to the leaf nitrogen content at anthesis stage, and also highly significantly correlated to the final grain protein content (R² = 0.46). Secondly, the external conditions, such as irrigation, fertilization and temperature, had important influence on grain quality. Water stress at grain filling stage can increase grain protein content, and leaf water content is closely related to irrigation levels, therefore, the spectral indices correlated to leaf water content can be potential indicators for grain protein content. The spectral reflectance of TM channel 5 derived from canopy spectra or image data at grain filling stage was all significantly correlated to grain protein content (R² = 0.31 and 0.37, respectively). Finally, not only this study proved the feasibility of using remote sensing data to predict grain protein content, but it also provided a tentative prediction of the grain protein content in Beijing area using the reflectance image of TM channel 5.     

多源遥感数据支持下的城市生态状况评价

城市生态环境监测具有数据来源广泛、监测要素复杂、服务对象多样等特点,整合可用的资源进行城市生态的综合监测成为目前关注的热点。本文利用高分辨率遥感影像,以及地表覆盖、城市边界等遥感产品,在现有遥感生态指数的基础上,结合黑臭水体指数,构建适合综合评估城市生态状况的集成遥感监测模型,实现对城市生态环境状态的多维度监测。该方法能够较准确客观地反映城市的生态环境质量,理论上补充了基于遥感数据的城市生态环境监测方法,可为城市生态环境监测的信息化建设提供技术支撑。     

行星遥感影像目标识别与分类进展

从行星遥感海量数据中对地形地貌特征进行识别和分类,是行星科学研究中的一项重要基础工作.本文综述了自实施月球和深空探测任务以来,国际、国内采用行星影像数据进行地形地貌识别与分类技术的研究进展.首先,从月球、火星以及其他行星探测任务3个方面,对相关的探测任务和获取的影像数据进行简介.然后,在介绍通用目标识别与分类方法研究进...     

Village level crop inventory using remote sensing and field survey data

This paper presents results of a pilot study in six villages located in the states of Haryana, Rajasthan and Madhya Pradesh, to evaluate accuracy of crop area at village level estimated by IRS - LISS-I1I data with respect to detailed field survey carried out by National Sample Survey Organization. The selected villages were located in Karnal, Kota and Bhopal districts which represented single dominant wheat crop as well as wheat-mustard and wheat-gram situation, respectively. Accuracy assessment of remote sensing based estimate with field survey of NSSO showed relative deviation in wheat estimate ranging from 3.72 percent for Mainmati village in Karnal district in Haryana to 22.65 percent fo Ranpur village in Kota district of Rajasthan. It was found that relative deviation in area estimation is inversely poportional to the crop proportion in that village. Observations of over estimation at low crop proportion and underestimation at higher crop proportion was explained by simple budgeting of relative proportion of ommision and commision errors. The study demonstrates that on the average, 90 percent crop area accuracy is possible with LISS-II1 data and the adopted approach.     

Landscape analysis for pedo-geomorphological characterization in part of basaltic terrain,central India using remote sensing and GIS

In the present study, an attempt has been made to analyse IRS-ID LISS-III satellite data in conjunction with field observations for geomorphological mapping and pedo-geomorphological characterisation in Mohgaon area of Nagpur district, Maharashtra. Analysis of satellite data reveals distint geomorphological units viz., plateau top, isolated mounds, linear ridges, escarpments, plateau spurs, subdued plateau, rolling plains, pediments, narrow valleys and main valley floor. Soil profiles, studied on different identified landforms, showed variation in site and morphological charactaristics. Moderate soil erosion occurs on plateau top, isolated mouds, plateau spurs, rollinmg plains and pediments. Severe erosion was identified on escarpments and subdued plateau and narrow valleys suffer very slight erosional hazards. Moderately well drained soils were found on rolling plains, pediments, narrow valleys and main valley floor. Well drained soils were noticed on plateau top and plateau spurs. Very shallow soils were found on the plateau top and isolated mounds. Shallow soils are found in linear ridges, escarpments, plateau spurs and rolling plains. Moderately deep and deep soils are found on subdued plateau, pediments and main valley floor. The landform-soil relatioinship reveals that the soils on the plateau top and isolated mounds are very shallow, well drained, clay textured. The soils on the narrow valleys and main valley floor are deep, moderatly well drained, and clayey in texture. It also indicates that landform-soil processes are governed by physiographic position, drainage, slope and erosion conditions of the area. The present study reveals that the analysis of remotely sensed data in conjunction with field observations in GIS will be of immense help in geomorphology mapping, analysis of landform-soil relationships and generation of their geo-spatial database.     

Urban cadastral mapping using very high resolution remote sensing data

With growing urban expanses, one of the pre-requisites for effective governance is Urban Information Systems (UIS) with content down to individual properties (and individuals). The basic input i.e., a map, in UIS should show individual property boundaries showing the plan outline of all structures existing within, at a scale of 1:1000 and larger with sub-metre to centimeters planimetric and geometric accuracy. With very high resolution remote sensing data of the order of 1m available in hand, it is possible to prepare maps with high resolution spatial content. The present exercise demonstrates a method of preparing a geometrically and planimetrically accurate urban cadastral map on very large scale for a small area of about 5 sq km. IKONOS merged data with 1m resolution is used for the purpose. Mapping was done in conjunction with on-site measurements and sketches. Guides are used to maintain shape symmetry and accuracy of buildings and other features. Working out cost of mapping per unit area is another objective in the present exercise. For want of fully or semi-automatic methods of information extraction from very high resolution remote sensing data, it is imperative that mapping should be carried out in conjunction with some on-site measurements wherever necessary.     

Analysis of population dynamics using satellite remote sensing and US census data

The population dynamics from 1991 to 2006 for the seven-county Twin Cities Metropolitan Area (TCMA), Minnesota, USA, was analysed in this study. Per cent impervious surface areas (%ISA) for 1991, 1999 and 2006 were derived from Landsat Thematic Mapper (TM) images and were modified using two different masking methods. The modified %ISA images of 1991 and 1999 were correlated with 1990 and 2000 census block group data of the ‘two highly developed counties’, ‘five suburban counties’ and ‘all seven counties.’ Populations of both years were then modelled, assessed and compared. Next, the statistical models based on the 1999 %ISA and 2000 census data were applied to the 2006 residential %ISA image to estimate the 2006 population. These 2006 estimates were compared with census county-level population projections for 2006. In comparison to Method A, which uses ‘adjusted %ISA images’ by masking out highway centrelines and areas that have greater than 75% imperviousness, Method B based on ‘pure residential %ISA image’ has higher coefficient of determination (R ²) and much lower, consistent mean absolute relative errors (MARE). For both methods, the strongest R ² and lowest MARE values between modelled population density and true density were found in the five-county model, followed by the seven-county model. The two-county model ranks last in terms of model performance for both years. In general, populations for the two highly developed counties were underestimated whereas the opposite was true for the five suburban counties. Population was most accurately estimated based on data from counties with the same or similar characteristics. By comparing the 1990/1991 and 1999/2000 models, we also found that the rate of population density per unit of impervious surface declined from 1991 to 1999. High accuracy was achieved when applying the 1999/2000 model to predict the 2006 population, suggesting that the relationship between per cent imperviousness and population density were relatively stable between 1999 and 2006.     

Derivation of indices using remote sensing data to evaluate cropping systems

This paper presents the work done in Bathinda District of Punjab state of India for evaluating the cropping system efficiency using multi-date, multi-year and multi-sensor satellite based remote sensing data along with various spatial and non-spatial collateral data. Three efficiency indices, such as Multiple Cropping Index (MCI), Area Diversity Index (DI), Cultivated Land Utilization Index (CLUI), have been worked out to characterize the cropping systems. The salient findings point out that, the MCI has, increased remarkably. A further increase is possible by only taking a third crop. The ADI has increased in kharif (rainy) season, due to introduction of rice in the cotton belt, however in rabi (winter) season the ADI has reduced nearly to one, showing it to be a mono-cropped situation. The CLUI is low (> 0.5) in many blocks, showing there is a great scope to improve it. Since in summer the land is remaining unutilized, a summer crop can very well be taken up to improve it.     

Geomorphological analysis for inventory of degraded lands in a river basin of basaltic terrain using remote sensing and GIS

In recent years, the use of remotely sensed data and Geographic Information System (GIS) applications has been found increasing in a wide range of resources inventory, mapping, analysis, monitoring and environmental management. Remote sensing data provides an opportunity for better observation and systematic analysis of terrain conditions following the synoptic and multi-spectral coverage. In the present study, the geomorphological analysis reveals that various denudational and depositional landforms have been analysed and mapped. The soil depth ranges from extremely shallow in isolated mounds to very deep in the pediplains. Based on the slope gradient, morphometry, soil depth, vegetation cover and image characteristics of standard FCC imagery of IRS-1D LISS-III data, four categories of eroded lands i.e., very severe, severe, moderate and nil to slight have been identified and mapped. The integrated analysis of slope, geomorphology and degraded lands layers in GIS revealed that the pediplains, rolling plains and subdued plateau are associated with very severe land degradation and accounts for 6.05%, 3.85% and 3.47% of total area respectively. The analysis of percentage of degraded lands at geomorphic sub unit level indicates that severe land degradation process is dominant in the dissected ridges, isolated mounds, escarpments and plateau spurs. The remote sensing data and GIS based detailed geomorphological and degraded lands analysis ensure better understanding of landform-eroded lands relationship and distribution to assess the status of land degradation at micro geomorphic unit for reclamation, geo-environmental planning and management. Similar study also helps in the areas of natural resource management, environmental planning and management, watershed management and hazards monitoring and mitigation.     

基于多源遥感的沼泽湿地水文边界界定方法研究

湿地边界的界定研究是湿地科学的基础研究.湿地水文特征是界定湿地边界的唯一可靠标准.论文以洪河自然保护区为试验区,围绕湿地水文特征指标,构建了沼泽湿地的"淹埋深-历时-频率"阈值研究的理论和方法,并利用沼泽植被边界处的长时间序列的"水位-历时"过程线反演了湿地的"淹埋深-历时-频率阈值",并利用该阈值界定了湿地水文边界,...