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Utilizing Landsat tm imagery to Map Greenhouses in Qingzhou, Shandong Province, China

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Pedosphere 2004年第3期14卷 363-369页

作者： ZHAOGeng-Xing LIJing LITao YUEYu-De T.WARNER CollegeofResourcesandEnvironment ShandongAgriculturalUniversityTai＇an271018（China） SoilandFertilizerWorkingStationofShandong Jinan250100（China） AgricultureBureauofQingzhouCity Qingzhou262500（China） DepartmentofGeologyandGeography WestVirginiaUniversityMorgantownWV26505-6300（USA） CollegeofResourcesandEnvironment ShandongAgriculturalUniversityTai＇an271018（China）

To build a rapid and accurate method for greenhouse vegetable landinformation extraction using an index model derived from tm digital data of Qingzhou City, ShandongProvince, based on a systematic analysis of the spectral characteristics of different land use typesin the study area, a subset of the image was first made to eliminate the mountainous region notassociated with vegetable distribution, and then water body pixels were masked. With this the V_Iindex model for greenhouse vegetable land extraction was developed. The index model indicatedgreenhouse vegetable land for Qingzhou in April 2002 was concentrated in the southeast and aroundrural residential areas. Field data used for an accuracy evaluation showed that greenhouse hectaresdetermined with remote sensing were 95.9% accurate, and accuracy for the spatial distribution ofgreenhouse vegetable land cross checked with a random sample was 96.3%. Therefore, this approachprovided an effective method for greenhouse vegetable land information extraction and has potentialsignificance for management of greenhouse vegetable production in the study area, as well as NorthChina.

关键词： greenhouse vegetable land information extraction qingzhou city tm image

A model for the retrieval of suspended sediment concentrations in Taihu Lake from tm images

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Journal of Geographical Sciences 2006年第4期16卷 458-464页

作者： GUANG Jie WEI Yuchun HUANG Jiazhu Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal UniversityNanjing 210097 China

A study was conducted in the Taihu Lake with the aim of deriving a model for the retrieval of suspended sediment （SS） concentrations from Landsat tm images and in situ sampled data. The correlation between suspended sediment concentrations of lake and the reflectance obtained from the tm images is significant. By tm images and in situ sampled data in summer and winter, we obtained a comparative uniform model for the retrieval of suspended sediment concentrations in the Taihu Lake, that is lnSS = a＊（R3/R1）＋ b, where lnSS is the natural logarithm of the suspended sediment concentration, Rl and R3 are the reflectance coincident with the 1st band and the 3rd band in tm images, a and b are the regression coefficients. Furthermore, we analysed the errors particularly to make sure the model is valid. The model is accurate to within 0.33（RMSE）, suggesting that this model may be applicable to predict suspended sediment in the Taihu Lake from tm image throughout the year.

关键词： suspended sediment tm image Taihu Lake

Water bodies extraction from tm images

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Journal of Measurement Science and Instrumentation 2014年第3期5卷 48-52页

作者：杜先荣中北大学信息与通信工程学院山西太原030051 山西省光电信息与仪器工程技术研究中心山西太原030051

Aiming at the problems of high time-consuming, low accuracy and weak versatility of the existing methods of wa- ter extraction based on tm image, this paper combines principal component analysis （PCA） with the modified normalized difference water index （MNDWI） which was improved by XU Han-qiu to construct a false color composite image that could separate water from others easily. This method can realize the water extraction based on tm image by analyzing the spectral characteristics of water in this false color image and establishing a water extraction model. This paper also compares the effi- ciency of this method with MNDWI, （tm2 ＋ tm3） - （tm4 ＋ tm5） and new water index （NWI）, which were applied in the city and mountain of Taiyuan, respectively. The results show that the proposed method can extract water body from tm im- age more rapidly and efficiently and its accuracy is up to 94.03 %. In addition, this method does not require a manual selec- tion threshold, which meets the research reuuirement of high automaticm.

关键词： tm image water extraction principal component analysis (PCA) modified normalized difference water index(MNDWI)

Estimation of forest parameters based on tm imagery and statistical analysis

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Journal of Forestry Research 2007年第3期18卷 241-244页

作者： CHEN Wen-bo ZHAO Xiao-fan College of Land Resources and Environment Jiangxi Agricultural University Nan Chang 330045 P.R. China Institute of Applied Ecology Chinese Academy of Science Shenyang 110016 P.R. China Graduate School of Chinese Academy of Science Beijing 100039 P.R. China

One of the primary forestry research interests lies in estimating forest stand parameters by applying empirical or semi-empirical model to establish the relationship between the forest stand parameters and remote sensing data. Using remote sensing image and the inventory data from 2 compartments in northeast Florida, U.S.A., this paper explored the correlation between forest stand parameters and Landsat tm spectral digital number （DN） value. Results showed that less than 50% of the total variance could be explained by linear regression models with only either a single band or such vegetation indices as vegetation index （VI） or normalized difference vegetation index （NDVI） as predicators. In consequence, multi-linear regression models which synthesized more predicators were introduced to estimate forest parameters. Regression results were tested in terms of the other group of data, and verification showed a better capability of explaining over 75% variance except for forest density. The weakness and further improvement of prediction models were also discussed in the article. This paper is expected to provide a better understanding of the relationship between tm spectral and forest characteristics

关键词： tm image DN value Estimation of forest parameters Correlation and regression analysis

Interpretation of remote sensing of geological structures and prediction of gold mineralization in Mohe area and its adjacent region

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Global Geology 2007年第1期10卷 88-94页

作者： Ruiqing QIE Linfu XUE Shixiang LIU Yunliang YU College of Earth Sciences Jilin University Changchun 130026 China College of Management Jilin Agricultural University Changchun 130118 China

The authors took the Etm+ multi-spectra data as the data information and correlation coefficient for each band and carried out their information volume *** to certain criteria,the authors also determined the optimum band-combined *** image clarity is improved by various enhancements and fusions *** on remote sensing geological interpretation in detail,the relationship between remote sensing geological characters and gold mine were analyzed *** all kinds of remote sensing structure information,combining other research data,the authors determined mainly ore-controlling ore *** prospective areas of gold ores were determined and furthermore significant finding mine target areas was confirmed.

关键词： tm image linear structure ring structure gold deposit Mohe area

Application of an expert knowledge system in the study of forest spatial patterns

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Forest Ecosystems 2008年第1期10卷 52-55页

作者： LI Chun-yan, ZHANG Xiao-li* Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083, P. R. China Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry University Beijing P. R. China

For the sake of exploring how the pattern of Chinese pine (Pinus massoniana Lamb) community changed after the invasion of the pine wood nematode (Bursaphelenchus xylophilus (Steiner & Buhrer) Niclde) in Zhoushan, Zhejiang Province, we established a test area in the local Chinese pine community. Landsat5 tm images from 1991 and 2006 were integrated with auxiliary data from field investigation and spectral data as additional sources of information. A method of expert knowledge classifier was applied to establish the expert knowledge dataset of the main vegetation cover types from which we obtained a forest type distribution map. The spatial patterns and stability of the forest, before and after the invasion of the pine wood nematode, were analyzed in terms of community patterns. The results indicated that the predominant coniferous forest type changed to a mixed forest. As a result, the forest structure became complex and the interaction between coniferous forest patches became weakened over the period from 1991 to 2006. Therefore, the resistance of the forest eco-system to plant diseases and insect pests and the stability of forest eco-system enhanced.

关键词： expert knowledge system tm image forest pattern stability

A comparative study of the denoising methods of Thematic Mapper images for forest areas

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Journal of Forestry Research 2007年第2期18卷 123-127页

作者：赵正勇王立海东北林业大学哈尔滨150040

The noises of remote sensing images, caused by imaging system and ground environment, negatively affect the accuracy and efficiency in extracting forest information from remote sensing images. The denoising is critical for image classifications for forest areas. The objective of this research is to assess the effectiveness of currently used spatial filtering methods for extracting with forest information related from Landsat 5 tm images. Five spatial filtering methods including low-pass filter, median filter, mean filter, sigma filter and enhanced self-adaptive filter were examined. A set of evaluation indices was designed to assess the ability of each denoising method for flatness, edge/boundary retention and enhancement. Based on the designed evaluation indices and visual assessment, it was found that sigma filter （D=1） and enhanced self-adaptive filter were the most effective denoising methods in classifying tm images for forest areas.

关键词： Denoising Edge/boundary retention Enhanced self-adaptive filter tm image