Showing papers in "Remote Sensing Technology and Application in 2008"

Estimation on Suspended Sedimentation Concentration of Poyang Lake Using MODIS and Hyperspectral Data

Abstract: This study aimed to search for the estimation model for suspended sediment concentration(SSC) using Moderate-resolution Imaging Spectroradiometer(MODIS) of medium-resolution data and using hyperspectal reflectance data to identify the most sensitive hyperspectral band.In this study,the utility of MOIDS data and hyperspectral data for analyzing turbid water was examined in Poyang Lake.The spectral characteristics of water surface with high SSC were determined by hyperspectral measurements during the field survey in seven sample points.The regression analysis using hyperspectral data was the basis of the approach using remote sensing data.A strong linear relationship(R2 = 0.91;n = 25) was established between band 1 MODIS Terra 250 m reflectance and in situ measurements of SSC acquired from different environments in Poyang Lake Basin.The moderate resolution of MODIS 250 m data and the operating characteristics of the instrument provide data well suited for assessing temporal and spatial patterns of SSC in Poyang Lake.Finally,the historical images were analysed using the calibrated model to map the suspended sediments concentrations.Based on monitoring the sequence of suspended sediment concentration during the flood season,the configuration of the back flows of water from Yangtze River can be observed.

Study on Land Use Suitability Assessment of Urban-Rural Planning Based on Remote Sensing——A Case Study of Liangping in Chongqing

Abstract: In this paper,2006 TM image of Liangping is used to land use interpretation.The objective is to analyze and evaluate various impact factors on urban-rural planning land suitability via GIS-based Spatial Analysis method,to construct comprehensive evaluation model of urban-rural planning land suitability(Weighted sum model) and to incorporate the evaluation model to comprehensive land use suitability assessment in the region of Liangping.

Selection of Optimum Periods for Extracting Winter Wheat Based on Multi-temporal Remote Sensing Images

Abstract: Selection of optimum periods of vegetation classification is important for extracting crop planting area.Based on Landsat TM images and Spot-2 images in Beijing,spectral distance between winter wheat and other ground targets was calculated,and the phenological difference of main vegetation types in Beijing was analyzed.Then winter wheat was classified from each individual image or their combinations using maximum likelihood classification algorithm.Finally,based on ground surveyed samples and visual interpretation,the classification results were evaluated by overall accuracy and classification efficiency index for different cases.The results shows that:(1) the optimum periods for extracting winter wheat is early April(rising stage) with an overall accuracy of 92.9%;(2) the optimum combination for winter wheat identification is early April and late May(grain-seeding stage) with an overall accuracy of 94%.

Classification of Urban Land Based on Object-oriented Information Extraction Technology

Abstract: Object-oriented information extraction technology compared with the pixel-based classification method is suitable for classification of high resolution remotely sensed images.Object-oriented image analysis has two key technologies,multi-scale image segmentation and classification technologies based segmentation.Urban area of Huairou was selected as study area,and the purpose is to extract information from QuickBird image using above approach.The conclusions are: ①"pepper and salt" noises are discarded;② 84.82% overall accuracy is achieved while only 73.87% is achieved with traditional pixel-based method.Furthermore,precision of each kind of object information was also improved,particularly for grass,roads and building shadows.

Application of MODIS Data for Monitoring Blue-green Algal Bloom in Chaohu Lake

Abstract: Taking Chaohu Lake as an experimental site,unify the orbit water quality monitor data,using the simple regression and multivariate regression,the semi-empirical models for determinating chlorophyll-a concentration in Chaohu Lake are developed by relating the MODIS 250 meter resolution wave band combinations to chl-a measurementsThen,the distribution of blue-green algal bloom in Chaohu Lake is mappedThe intensity,place and distributed scope of this blue-green algae bloom reflected clearlyThe results of this study show that MODIS image data is useful in Monitoring blue-green algal bloom in Chaohu LakeThe ratio of band 2 to band 1 (r2/ r1) with 250m resolution is suitable to retrieve chl-a concentration because it is well related with chi-a measurements(R= 09093)

Research and Application of the Poyang Lake WetLand Classification Using Remote Sensing

Abstract: Different classification in wetlands is synthesize to classify by remote sensing.Through analyzing trait of the spectrum symbols,different parameter change,space configuration's difference,land-cover's seasonal variability and so on.Different wetlands types adopt different method to distinguish,lastly a synthesis classification method from easy to hard is established effectively.A typical case from PoYang lake.Classification using by this method cann't only lighten a mass of people's work but also improve classification's precision.

The Extraction of Freshwater Marsh Wetland Information Based on Decision Tree Algorithm——A Case Study in the Northeast of the Sanjiang Plain

Abstract: Wetlands are considered an integral part of the global ecosystem.Enhancement of their scientific management informed by quantitative,accurate and repeatable observations of wetlands' landscape would obviously be significant.Taking the northeast of the Sanjiang Plain as a case study,we use classification and regression tree(CART) algorithm for purposes of mining classification rules from training samples.Classification tree model of wetland information extraction was built from these samples through CART algorithm,which integrates spectral,texture and the assistant geographical characteristics.The classification results based on CART algorithm were checked by statistical confusion matrix accuracy assessment using field GPS samples.Validation shows that total classification accuracy is 82.65%,Kappa coefficient is 0.7935.The results had suggested that the accuracy of classification based on the CART algorithm was higher than the MLC supervised classification method.The developed method is portable,relatively easy to implement,and should be applicable in other settings and larger extents.

Drought Remote Sensing Monitoring Based on the Surface Water Content Index(SWCI) Method

Abstract: Soil Moisture and Vegetation Growth are the most important and direct index in drought monitoring,and the spectral interpretation of vegetation and soil are serious factors in the judgment of drought degreeBased on the spectral character of water,recently,a new model of Surface Water Content Index(SWCI) has been put forward,and the index is more sensitive to the surface water content,and suit for regional drought monitoringThe comparative analysis showed that SWCI is more sensitive than NDVI to monitoring surface soil water content,it is available in real-time soil drought monitoring

The Land Cover Classification and Characteristics of Nansihu Lake Based on SPOT5 Remote Sensing Image

Abstract: Two SPOT5 imageries of Nansihu Lake(middle of June,2006) were interpreted to classify the land cover,using ERDAS Imagine and ArcView.As the fishpond and the open water-body were difficult to be distinguished,unsupervised classification and manual interpreting were used.The accuracy of interpretation classification was 83.3% after checking.The land cover classification types were mapped and the area of each type was calculated.The overall area of Nansihu Lake is 1206.9 km2,only 45.54% belongs to open water.Other lands are covered with wetland vegetation,fishpond,farmland and forests,with proportions of 21.06%,15.60%,11.23% and 5.66%,respectively.The land cover characteristics were also analyzed based on the map.To protect the ecological system of the lake,making land by separating the lake should be prohibited and the aquatic agriculture should be regulated through government regulations.

Detection of Robinia Pseudoacacia Planted Forest Canopy Health Using Landsat ETM+ Image Data

Abstract: 通过发展一种基于单景Landsat TM/ETM+数据客观、可靠、简单易行的人工刺槐林冠健康检测方法，为人工刺槐林地健康监测和管理服务。以孤岛林场的一块近乎纯人工刺槐林地为试验区,首先选择当地刺槐完全展叶时的2000年5月2日的Landsat ETM+数据进行几何精校正，并将第6波段重采样为与第1~5和7波段相同的空间分辨率30 m，然后将波段1~5和7波段数据校正到大气顶层反射率以减少传感器和数据获取方面的影响，利用第6波段计算亮度温度。接着进行3种组合的ISODATA非监督分类（健康或轻度枯梢、中度枯梢、重度枯梢或死亡或灌丛、非植被）：波段1~5和7，归一化后的缨帽变换Tasseled Cap Transform（TCT）绿度和湿度成分，归一化后的缨帽变换Tasseled Cap Transform（TCT）绿度、湿度成分和亮度温度。结果发现，增加了第6波段信息（亮度温度）的第3种组合对人工刺槐林冠健康检测更有效。

Monitoring of Crop Residue Burning in North China on the Basis of MODIS Data

Abstract: Crop residue burning has a great negative impact on the ecosystem and environment in China.Remote sensing can provide abundant information of surface fire and thus support the government to forbid the crop residue burning effectively.Although "Contextual Fire Detection Algorithm" is an automatic fire-detecting algorithm with good accuracy,its fixed parameters and thresholds can not perform well in detecting fires of different kinds or in varied situations.Therefore some of the key parameters are adjusted according to the practical observations,in order to better monitor the surface fire in China.On the basis of data from EOS/Terra-MODIS,the crop residue burning in North China has been monitored from May to August in 2007,the accuracy of which can satisfy the requirement of practical applications.In addition,based on the IGBP classification data,the detected fire pixels are separated into 3 types of biomass burning,namely crop residue burning,forest fire and grass fire.Then the statistics and analysis of several parameters of the 3 types of fire are implemented respectively,on the basis of which the possibility of identifying the type of fire pixels according to their radiant characteristics is discussed.It is concluded that surface classification data is still necessary when identifying the fire pixels.

The Application and Evaluation of Two Methods Based on LSMM Model——A Case Study in Guangzhou

Abstract: Currently,there were lots of methods on urban impervious surface researching,such as Linear Spectral Un-mixing method,Non-linear Spectral Un-mixing method,Matched Filtering method and so on,however, among all these methods the Linear Spectral Un-mixing method was applied popularly and wildly by the researchers.The Linear Spectral Un-mixing method based on Linear Spectral Mixing Model (LSMM) and obtained the proportion of each land types in each pixel through un-mixing each pixel in the remote sensing image.This paper used Purity Pixel Index (PPI) and manual selection method to select end-member and gained the abundance images of each end-member in each pixel and the RSME image by using linear spectral un-mixing method.At last,it obtained the impervious surface weight image of 8 areas in Guangzhou.Besides,this paper analyzed the two end-member selection methods and evaluated the precision of the result from the qualitative standpoint.The result revealed that the method could abtain the impervious surface weight image of 8 areas in Guangzhou efficiently and the manual selection method could gain the weight image with more precision than the PPI method.

Change Detection of Inundation Extent of Poyang Lake Wetland Using Multipolarized SAR Images

Abstract: It has some advantages to detect the inundation extent using Synthetic Aperture Radar(SAR) images.In this paper,Change Vector Analysis(CVA) is a valuable approach for the surface inundation extent.As a result from the case study in Poyang Lake wetland,the multipolarized Envisat ASAR data is used to detect the inundation extent,and the change areas were extracted using the classification method of decision tree.Finally,the potential utility in Change Vector Analysis for change detection of SAR images was discussed.

Differences of Lake Color between Mapangyongcuo Lake and La'angcuo Lake Based on Remote Sensing

Abstract: Lake color is an important index of water optical properties.Because of its special geographical conditions,color of lakes in Qinghai-Tibet Plateau is significantly different.In this paper,Mapangyongcuo Lake and La'angcuo Lake in the south of Tibet were chosen as research.Starting from the image representation of the two lakes' color,remote sensing technology was used to analyze the differences.As shown in the results that,evaporation and recharge of the two lakes were different,so the substance deposition such like salt were different,and then influenced the lake color.This is a new method to research on lakes in Qinghai-Tibet Plateau that are lack of observed data.

Extracting Soil Moisture from Landsat Imagery of Xiamen City Using a Spectral Feature Space Composed of Fractional Vegetation Cover and Land Surface Temperature

Abstract: Soil moisture is an important variable in hydrology,meteorology and agriculture science.In this study,two Landsat TM images of Xiamen city were used to evaluate soil moisture of the city for the years of 1989 and 1996.The extraction of the moisture was based on a spectral feature space composed of fractional vegetation cover and land surface temperature.Furthermore,the change of soil moisture of Xiamen city during the study period was also detected.The study revealed that the moisture of the downtown area in the southeast of Xiamen has increased,while the moisture in the north area was significantly reduced,which is due largely to the urban expansion to this area during the period.

Study on Automatic Extraction of Grand Canal Based on SPOT-5 Image

Abstract: The Grand Canal of China is the longest ancient canal in the world and the alive heritage.As the main artery between the northern and the southern,it plays an important role in history.The Grand Canal is the combination of cultural heritage,intangible cultural heritage and natural heritage.Only by safeguarding the canal well can we realize the goal that Grand Canal can apply the World Legacy successfully.The fact that the spatio-temporal span of Grand Canal is large made the investigation difficult especially in the conventional way.Remote Sensing plays an increasing important role in the contemporaneity archaeology by right of the advantage of advance,convenient and economic.The RS images record the distributing and the status quo of the canal in different courses of history.The article analyses the spectral and spatial feature in order to extraction the canal automatically with the RS and GIS technology.The extraction of canal can provide the information for the application for World Legacy of the Grand Canal and offer the protection layout deciding support.

Tobacco Field Monitoring and Classification Method Study in Mountainous Area

Abstract: Tobacco is one of the important crops in our country and brings the significant irreplaceable effect into playing in countrywide economic growth.So the monitor and scientific management of tobacco fields is especially important to us.At present, the study of tobacco remote sensing monitoring is less both at home and abroad.In this paper, we try to obtain tobacco field and area by remote sensing with Yunan Province Hong He State Tobacco County as example.We adopt rejecting interfering tobacco field information classification method of supervision while monitoring and get an ideal result.Simultaneity, we also offered the suggestion of further improving classification precision.

Analysis of the Spectrum Feature of Different Vegetable in Tengchong County of Yunnan Province

Abstract: The measure and analysis of the spectrum of vegetables is very important for applying remote sensing in identifying vegetable.The spectrum data of the different vegetables such as Chinese cabbage,garden pea,cattle vegetable,verdure,garlic,onion,parsley are gotten by using SE590 hyper-spectral radiometer in Tengchong county of Yunnan province.The spectrum curves of the vegetables are made based on the spectrum data.The spectrum feature is analyzed based on the spectrum data.The first order derivative transfer was carried out in the spectrum data.The first order derivative feature is analyzed.It is shown that:The vegetables can be divided into two groups according to their reflectivity during 400nm to 679nm.The first group with higher reflectivity includes Chinese cabbage,garden pea,cattle vegetable,verdure.The second group with lower reflectivity includes onion,garlic and parsley.Each vegetable can be differentiated from each other according to the peak value,valley value and slope of their spectrum curves,and their reflectivity value in the first group.Each vegetable can be differentiated from each other according to their reflectivity values during 726nm to 1 100nm in the second group.The unique first order derivative feature can be used to identify Chinese cabbage,garden pea,garlic,onion and parsley.

Research on Copolarized Correlation Characteristic from Bodunqi Alluvial Fan Using Full-polarized SAR Data

Abstract: Paleoclimate can be extricated from alluvial fan by using full-polarized Synthetic Aperture Radar(SAR).Polarization coherence ρ is an important parameter to characterize the ground scatterers(|ρ| is polarization coherence coefficient,the phase of ρ is phase difference).In this paper,the distribution of ρ is extricated from Bodunqi Alluvial Fan using Shuttle Imaging Radar-C(SIR-C) L band fully-polarized data.The results show that ρhhvv(ρ between Shh and Svv) can well characterize the alluvial fan.Besides,we researched the relationship between ρ and ground parameters of Bodunqi Alluvial Fan such as roughness and moisture in this paper.It indicates that the phase difference between Shh and Svv and the |ρ| between Srr and Sll can be affected by ground parameters.

Applying Geo-data Mining to Analysis Spatial Variance Characters of Urban Land Surface Temperature

Abstract: In this paper,the main city of Shanghai is chosen as the study target,based on Landsat ETM+ images.Using Mono-window Algorithm to calculate land surface temperature,spatial variance of land surface temperature is analyzed by applying the Geostatistical method.The results show that the spatial difference of land surface temperature is significant and asymmetric distribution of east-west direction.The land surface temperature of Pudong area is obvious lower than Puxi area.The lowest temperature zone is located at the junction of the southern part of Pudong District and Nanhui District,but the highest temperature zone is distributed in Puxi area,including city centre along the Huangpu River,the southern of Baoshan District and northern of Putuo District.The land surface temperature is between highest and lowest temperature in other districts.From the view of the spatial variance of land surface temperature,at the lesser spatial scales,spatial heterogeneity caused by random factors is larger proportion of the total,and spatial autocorrelation is unconspicuous.With the scale augmenting,the spatial heterogeneity caused by random factors share decrease and spatial autocorrelation increase.When the grain size is 180m and 540m,the land surface temperature has the moderate degree of the spatial autocorrelation,and when the grain size increases to 1080m,the spatial autocorrelation of land surface temperature is obvious.

Application of Semivariogram Texture Distilling for Remote Sensing Image Classification

Abstract: In the methods of improving the classification precision of remote sensing images,adding textural information as an expanded eigenvector into feature space is a pretty useful methodIn this paper,the author extract texture using spatial connections between geo-objects,then put it into the classification processThis experiment shows a nice resultThrough the problems encountered in this experiment,we discussed the appropriate scope of this methodology

Research on Filtering Methods of InSAR Processing

Abstract: The quality of interferogram will directly affect phase unwrapping,so interferogram filtering,which eliminate noise and improve quality of interferogram,is an important step of InSAR.In this paper,we studied several filter methods used in InSAR,including azimuth and range direction filter,multi-look filter,medium filter,gradient-based adaptive filter and Goldstein adaptive filter.

Evaluation on Fusion of CBERS-02B CCD and HR Images

Abstract: CBERS-02B carries a high-resolution and panchromatic HR camera and a multi-spectral CCD sensor.HR is high spatial resoluted and CCD is high spectral resoluted respectively.A intergrated and precise image can be acquired by fusing these two images.HSV、HPF、Brovey、IHS、SFIM and Wavelet transform are used to fuse Beijing'image of CBERS-02B HR and CCD.Through preservation of spatial detail and spectral information,fusion results are evaluated qualitatively and quantificationally.Several appropriate transforms are gained then.

Primary Studies on Estimating Soil Moisture in Deep Layer of Farmland by Remote Sensing in Yizheng

Abstract: 8-day composite MODIS temperature product MOD11A2 and 16-day composite MODIS NDVI product MOD13A2 were combined to construct Ts/NDVI space and the TVDI(Temperature Vegetation Dryness Index) was obtained.Every 16-day soil moisture in 40cm depth in different seasons in Yizheng was retrieved by TVDI.When compared with the soil moisture in 40cm depth measured simultaneously with satellite in the field,the mean error was 11.83% and minimum error reached 4.30%.The soil moisture distribution map shows that there were two high-value soil moisture areas,located in the Yangtze River alluvial plains in the southern part of Yizheng and the corner plains in the northwest part of Yizheng.The greater of the mean soil moisture is,the smaller of the difference between its high value and low value in the region.

Geolocation Method for FY-3 MWHS' Remote Sensing Image

Abstract: FY-3 MWHS scans the Earth's surface by mechanically rotating the antenna around X-axis.This research presents a geolocation method for FY-3 MWHS' remote sensing image based its scan geometry.It creates the spatial relationship model between the sensed data and the Earth based coordinate system,according to MWHS' sensing geometry and the sensor's attitude and position.This method is also including an algorithm of satellite orbit computation,which is used to get the satellite's instantaneous velocity vector from its position vectors.This method has been applied to FY-3 MWHS' remote sensing image geolocation.The geolocation result and error analysis use the land/water mask.Compared the geolocation results with the true remote sensing image,it shows that this method for MWHS' remote sensing image achieves pixel geolocation accuracy.

Study on Crops Classification Based on Multi-temporal NDVI and Characteristic Bands

Abstract: Spectral and temporal information can improve crops classification precision greatly.In this paper,4 multi-temporal TM SPOT images were selected on Youyi farm in Heilongjiang province.We used the NDVI as a new band information by extracting the NDVI information on the correspond time.By analyzing the spectral and time feature of the objects on each band,we designed a decision tree classified arithmetic.Finally,after series value division and mask management,the areas and distributions of dadou、yumi and shuidao were successfully remotely sensed with an overall accuracy of 98.67%.

Supervising the Salted Land Distribution of Hetao Irrigation Area in Inner Mongolia by Using Remote Sensing

Abstract: Land saltilization is a very important symbol of soil deterioration.It demands a lot of human efforts,materials and time to have an extensive study.While by remote sensing technology,the exact information about salted land distribution can be obtained in an efficient way at a low cost.After establishing a training sample,through the IRS-P6 saltilite photography,based on the pictures which are classified according to maximum likelihood,this essay analyzes the distribution of salted land in Hetao irrigation area of Inner Mongolia and gives an intensive evaluation.