Vegetation coverage plays an important role in decreasing soil loss, protecting environment and improving the standard of living. Therefore. it is very necessary to dynamically estimate the soil erosion in large area for guiding the environment protection activities. As the main information resources, remote sensing data can be applied widely for soil erosion estimation. In this paper, the main study focus on the methods of extracting vegetation coverage and estimating soil erosion by using remote sensing data,combining with other investigation information, for Guishuihe Drainage Basin, Yanqing county, Beijing.Firstly, the land-use map and vegetation coverage map of this basin were obtained using TM image and vegetation index model. Secondly, slope map was created from DEM. Thirdly, based on the soil erosion intensity classification, soil erosion intensity map was obtained by overlaying the maps of land-use,vegetation coverage and slope. Finally, soil erosion modulus in this basin was calculated according to the erosion area and intensity. The soil erosion and its spatial distribution were quantitatively analyzed. The result shows that the soil erosion in Guishuihe Drainage Basin is mainly in the very slight and slight degree, the area percentage of these 2 erosion intensities occupies 74.88%; while the erosion of strong and very strong degree are very limited, with an area percentage of less than 2%. The soil erosion modulus for whole basin was estimated as 1 746.1 t/km2·a.
In this paper, the collocated data from the precipitation radar (PR), TMI on the Tropical Rainfall Measuring Mission satellite (TRMM) and the hourly rainfall measurements from surface stations in Henan province of China were used to analyze several statistical algorithms for precipitation retrieval
over land. It is shown that it is hard to establish retrieval algorithm if we only use the regression relation between the hourly rainfall from stations and the microwave brightness temperatures. By using the temporal and spatial matching satellite data, several statistical algorithms have been obtained and then validated. The results show that the new algorithms can obviously improve the retrievals about 10-20% and reduce the error at least 25% for light (<5 mm/h ) and heavy (>10 mm/h) rainfall and yield same low retrieval precision for moderate rainfall (5～10 mm/h) in comparison with the statistical algorithms in the literature. In addition, the regression analysis results also show that precipitation retrieval over land can be improved to some extent by combining the low and high frequency radiometric channels.
Crown is a key part of tree. It' s the main place that photosynthesis has been taken place. It' s also the important energy sources that tree need to grow. So, some researchers often study how to monitor growth of tree, predict trees' life increment and judge the quality of wood, and so on by using remote sensing technique. The appearance of commercial high-resolution satellite data supplies new resources for people to study crown structure of a tree by using remote sensing technique. In this paper, method to detecting tree crown by using QuickBird image that covers the demonstration has been studied. Base on image process, Object-Oriented image analysis method has been taken. The tree crown has been effectively extracted from the QuickBird image by using Fuzzy Classification method that bases on samples. At the same time, it can give some experiment to process high spatial resolution satellite image and make a strong base for promoting the application of high-resolution satellite image in forestry and entironment construction of our country.
By means of digital image processing techniques of color image composing , image fusion,principal component analysis with landsat-7 ETM + image, combined with image recognizing and interpreting technologies based on geology knowledge, geological disasters along Motuo highway,
including debris flow, landslide, active structure, etc., have been completely analyzed, interpreted and mapped by themes in surveying of highway engineering geology with Remote sensing in Motuo of Tibet lied in Namjagbarwa region. The features of active faults along schedule route have been found out, both Palongzhangbu fault zone and Gangrigabu fault zone have a great influence on Cuola tunnel, five big landslides are distributed at both sides of Yaluzhangbu valley which lies in north slope of Namjagbarwa,there arc plentiful of debris flow and rockfall at Pai, Lage-Hanmi, Gangxiang-Bomi along Palongzhangbu and Yaluzhangbu valley, the result has provided enough scientific evidence for selecting highway route , evaluating engineering geology conditions.
Phenological and temporal information can improve crop classification precision greatly. In this paper, multi-temporal Landsat TM images were selected to extract winter wheat planting information in Beijing area. Firstly, four TM images were acquired on April 7, May 1, May 25, June 18, 2003, when winter wheat was at erecting, anthesis, grain filling and milking stage respectively. Secondly, considering the actual crops planting status in Beijing area, the multi-temporal NDVI curves of the main vegetations,including winter wheat, spring maize, clover, nursery, forest, were analyzed and extracted; Thirdly, a logical classification method was designed to extract winter wheat planted area, and the area and distribution of winter wheat harvested in 2003 was successfully remotely sensed with a precision of 96.92%. Finally, the remotely sensed results were compared with the statistical data of winter wheat reaped in 2002, and the winter wheat planting structural adjustment of each county in Beijing was analyzed. The result indicated that multi-temporal and multi-spectral remotely sensed data had obvious technological advantage and important application potentiality in monitoring crop-planting information.
Littoral shelter forest is very important for the ecological environment protection. Zhangzhou is coastal of Fujian province, which has a coastal line of 682 km. Therefore the construction of littoral shelter forest is very important for its ecological environment and the development of economy. TM images were used the most in environment application today. The article used remote sensing technology and Landsat TM images to distill littoral shelter forest information in 1998 and 2000 and analysed the results.Supervised classification and texture information were also applied in this paper. The final results indicated that littoral shelter forest is good as a whole but it has been some reduced during the study years. The local government should take some measures to strengthen the construction of the littoral shelter forest.Thus the littoral shelter forest can make full use of ecological, economic and social advantages. At the same time, the thesis classified the tree species and the result revealed that the littoral shelter forest of zhangzhou is mainly composed of seven species: Casuarina equisetifolia, Pinus elliottii, Acacia confusn,Pinus massoniana, mangrove,Pinu sthunbergii and nonage reproducing area. It is obvious that using multitemporal TM images to monitor littoral shelter forest is more quickly and efficiently than conventional methods.
TM data is used to extract the geological and mineralization information of Tongkuangyu copper deposit and its periphery. The image processing method is band ratio, principle component analysis and then the color composite image is formed. After the comprehensive study of ore-bearing strata, ore controlling faults and ring image features, metallogenic prognosis is made for the inner and outer of Tongkuangyu copper deposit. The remote sensing basis provides a new method to enlarge the exploration area in the outer of Tongkuangyu copper deposit.
Beijing will hold the 2008 Olympic Games. The main venue locates in northern Beijing, where there are villages, residential houses and commercial buildings. In order to help Beijing Olympic committee on the planning of housebreak and monitoring the construction implementation, supported by the project of Science and Technology Olympic Game and the Knowledge Innovation Project of Institute of Institute of Remote Sensing Applications (IRSA, CAS), IRSA used the airplane to obtain true color photos in July 2001, 2002 and 2003 respectively in order to monitor the progress of the housebreaking in the area. This paper introduced the change detection methods and the land use changes from 2001 to 2003 were statistically analyzed by the interpretation of the mosaiced photos, which show clearly the location of the housebreaking area, as well as the amount of houses or buildings. Until now 718 mu of houses or buildings remains to be broken down in near future. According to our plan for every June or July from 2004 to 2008,we will take airplane photos to detect construction progress and present the photos to the public.
Multispectral polarimetric imagery can provide several parameters of the man-made targets, including spectrum, intensity, state of polarization, and shapes. Among these, the state of polarization is additional useful information. It will help to improve the capabilities of the target detection and
recognition. Recently, an experimental multiband polarized CCD camera has been built in our laboratory.It can obtain the polarimetric imaging information at four bands subsequently. Here, We use one kind of man-made target as an experimental sample. Many digital polarization imaging data were acquired in the field and the laboratory. Thereby the Stokes parameters I, Q and U were calculated according to the measured radiance images of three polarization directions at 0o, 60o and 120o relative orientation of the transmission optic axis of the linear polarizer. At last, the angle of polarization (AOP) image and intensity image were derived from Stokes parameters, respectively. These images were only analyzed at 443 nm
waveband. The median filtering and single threshold method were adopted in angle of polarization image processing. Moreover, the vector images of the target were obtained. The result indicates that the properties of the man-made target and the background were characterized clearly by using the AOP parameter. The smooth surface of man-made target shows the coincident feature in AOP image. On the contrary, the surface of grass is unorderly. Indeed, it is the very function of the AOP image, which we want to illustrate. Hence, it shows that the AOP image can describe the different of surface orientations.Also, it may enhance the contrast between the man-made target and grass background. In a word, this new method based on the angle of polarization parameter can be used to discriminate the target from the background when we interpret the image of the polarized remote sensing.
Partial differential equation filters are well-known for their good processing results, but we must first solve an important question on optimal parameters selection because it affects the denoising results and the stability of the equation directly, which include the selection of diffusivity and optimal stopping time. This paper gets a right optimal stopping time in linear model by analyzing its analytical solution, and also decides the selection of diffusivity and optimal stopping time in nonlinear model from the aspects of both theory and application. The practical experiment results show that the selected parameters are best.
Sub-pixel classification is a tough issue in remote sensing field, the application of its calculation result is at primary, probation stage although many kinds of software and algorithm can be used to process this problems. After retrospecting the basic theory and methods of dealing with unmixing pixels, this paper made an introduction to the principles, algorithms, parameter setting and computing process of three Sub-pixel calculation methods (those are ILWIS3.0' s Linear Unmixing, Erdas8.5' s Sub-pixel Classifier,eCognition3.0' s Nearest Neighbor); conducted a case study of flood monitoring in Poyang Lake region with image data (scan time is August 11, 1998) of channels 1, 2 of NOAA AVHRR using the aforementioned three kinds of software and methods, the classified results are displayed in this paper.Second, a theoretic, practical and analytic comparison study was made of these three software and Sub pixel calculation methods in the aspects of Basic principles, Parameters to be set, Application fields and
their respective drawbacks. Finally recommended was the author' s opinion on the use (spatial assignment of sub-pixels of each pixel) of the calculation results (percentage of sub-pixels in each pixel) with these three Sub-pixel calculation methods in a hope to provide some reference to future similar application study to the RS scientists.
Different types of terrain would lie on the different site in the spectral space, which is the basic theory for remote analysis and recognition. Commonly, feature distill and analysis of mutispectral image is based on single pixel, texture, transformation, however, the essential feature-reflect spectral curve is not described directly in these algorithms. Since 1980' S, a new algorithm of binary encoding was put forward and applied in multispectral match recognition, new algorithm of TM image processing will be found based on this algorithm of feature distill. In this paper, a new algorithm for spectral shape description based on multi-threshold binary encoding is put forward, The key of this algorithm is that the range of terrain mutispectral is devided into several little gray range, what is called“multi-threshold”,each band is compared with several thresholds, then a binary code based on multispectral shape description is set up. And then this new algorithm is apllied in classifiction, information distill and change detect. The new algorithm is proved effective Through remote image experimentation.
The linear mixed mixture is a commonly accepted model for hyperspectral data processing. As the important parameter of the linear mixed mixture, endmember represents a certain ground component whose spectral is changeless comparatively. Over the past years, several techniques have been developed for accomplishing the determination of the endmembers in the literatures. Aimed at the disadvantages of these existing methods, this paper presents an automatic endmember extraction algorithm based on RMS error analysis. The new algorithm overcomes the insufficiency of other methods and needs less prior information. Not only the mean spectrum of the imagery is extracted, but also the anormaly is reserved.This algorithm also depends on the linear mixed mixture, it is executed directly on the data with no previous dimensionality reduction. The mean spectrum of the data is chosen to start the process, and then,a series of constrained unmixing operations is performed, each time selecting as endmembers the pixels that minimize the remaining RMS error in the unmixed image. This process is continued until the required number of endmembers is found or the unmixing error is below some threshold. The results of simulated and real hyperspectral data show the validity of the algorithm by a detailed comparative analysis with PPI.
Split-window algorithm is the main method to retrieve the LST by thermal infrared data. In this paper, we deduce a new Split-window algorithm which can be used to retrieve LST by using MODIS data on the basis of the common form of split window algorithm. Land surface emissivity and atmospheric transmittance are the two key parameters which are used to retrieve LST. As MODIS image has the lower resolution and vegetation, soil and water are the main three ingredients for MODIS image, we can estimate the land surface emissivity according to the ratio of three ingredients. We can estimate the atmospheric transmittance on the basis of the relationship between atmospheric transmittance and water content. At last we use this new Split-window algorithm to retrieve LST in JiangSu, and the graph of LST indicate the space difference, urban heat islaud effect and different ground object types.
Two key problems are solved in the first period of digitalizing the scanned Topographic Map.Traditional method, using image processing software, follows such steps: firstly select the reference point one by one and input their coordinates, secondly correct the whole map. This method is applicable to all kinds of images, but is not a special one for Topographic Map. And in the lab where super scanners are usually not available, another step is needed after correction and that is to patch together the topographic maps. In this paper, based on the analyses of the distortion characteristic of scanned topographic map, an experienced formula is put forward, and a special topographic map' s correction and patching software is developed with visual C++. The advantage of this software is that when correcting the images, there is no need to input the reference points' coordinates one by one any more, and indeed it offers a convenient and quick method to patch the images. Both absolute and relative examinations show that the range of error is less than 0.3%.
The classification of remote sensing is a process that all the pels in the image are separated into some species by their characters. The normal ways are Surpervised classification and Un-supervised classification. Supervised classification need enough prior knowledge. Un-surpervised classification is a process of clustering, which is separated or incorporated by some rules, it does not require the prior knowledge. But the traditional un-surpervised classification has some falts, for example, the lower precision,the coarse result, such as K-means, isodata. In this paper, a method, K-means in the Gauss and Rayleigh Distribution is introduced. From the result, we can find that the impact is more clear than traditional K-means.
Campus, as a miniature of city or area, has special characteristics itself in management of information. Campus geographic information system(CGIS) fills the defect of information management which there were no spatial data but only do attribute data. As we know, remote sensing(RS) data also have special characteristics which other data forms can' t comparable to,and become the main origin of CGIS data. At the same time they have put forward a new problem of the data fusing with GIS data. With the combination of JLUCGIS we expounded the structural model of JLUCGIS in this paper. Then, we solved the problem of data fusing and analyzed the interactive operation between the aerial RS image and GIS vector map, and finally gave the realization of JLUCGIS and the development of CGIS in the future.
