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A Method for Surface Roughness Parameter Estimation in Passive Microwave Remote Sensing

Chinese Geographical Science 2010年第4期20卷 345-352页

作者： zheng xingming ZHAO Kai Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Surface roughness parameter is an important factor and obstacle for retrieving soil moisture in passive microwave remote *** statistical parameters,root mean square (RMS) height (s) and correlation length (l),are designed for describing the roughness of a randomly rough *** roughness parameter measured by traditional way is independence of frequency,soil moisture and soil heterogeneity and just the ″geometric″ roughness of random *** ″geometric″ roughness can not fully explain the scattered thermal radiation by the earth's *** relationship between ″geometric″ roughness and integrated roughness (contain both ″geometric″ roughness and ″dielectric″ roughness) is linked by empirical *** view of this problem,this paper presents a method for estimating integrated surface roughness from radiometer sampling data at different frequencies,which mainly based on the flourier relationship between power spectral density distribution and spatial autocorrelation *** can obtain integrated surface roughness at different frequencies by this *** "geometric" roughness,this integrated surface roughness not only contains "dielectric" roughness but also includes frequency *** with Q/H model the polarization coupling coefficient can also be obtained for both H and V ***,the simulated numerical results show that radiometer with a sensitivity of 0.1 K can distinguish the different surface roughness and the change of roughness with frequency for the same rough *** confirms the feasibility of radiometer sampling method for estimating the surface roughness *** method overcomes the problem of ″dielectric″ roughness measurement to some extent and can achieve the integrated surface roughness within a microwave pixel which can serve soil moisture inversion better than the ″geometric″ roughness.

关键词： surface roughness passive microwave remote sensing statistical parameter estimation soil moisture radiometer

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An AMSR-E Data Unmixing Method for Monitoring Flood and Waterlogging Disaster

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Chinese Geographical Science 2011年第6期21卷 666-675页

作者： GU Lingjia ZHAO Kai ZHANG Shuang zheng xingming Northeast Institute of Geography and Agroeeology Chinese Academy of Sciences Changehun 130012 China College of Electronic Science ＆ Engineering Jilin University Changchun 130012 China）

Spectral remote sensing technique is usually used to monitor flood and waterlogging *** spectral remote sensing data have many advantages for ground information observation,such as real time and high spatial resolution,they are often interfered by clouds,haze and *** a result,it is very difficult to retrieve ground information from spectral remote sensing data under those *** with spectral remote sensing tech-nique,passive microwave remote sensing technique has obvious superiority in most weather ***,the main drawback of passive microwave remote sensing is the extreme low spatial *** the wide ap-plication of the Advanced Microwave Scanning Radiometer-Earth Observing System(AMSR-E) data,an AMSR-E data unmixing method was proposed in this paper based on Bellerby's *** utilizing the surface type classifi-cation results with high spatial resolution,the proposed unmixing method can obtain the component brightness tem-perature and corresponding spatial position distribution,which effectively improve the spatial resolution of passive microwave remote sensing *** researching the AMSR-E unmixed data of Yongji County,Jilin Provinc,Northeast China after the worst flood and waterlogging disaster occurred on July 28,2010,the experimental results demonstrated that the AMSR-E unmixed data could effectively evaluate the flood and waterlogging disaster.

关键词： passive microwave unmixing method flood and waterlogging disaster surface type classification AMSR-E MODIS Yongji County of Jilin Province

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Classification and Spatial Pattern of Township Development in Liaoning Province, China

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Chinese Geographical Science 2023年第4期33卷 708-718页

作者： LIU Xiaohui zheng xingming LIU Wenxin CHEN Xinyu Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China College of Resource and Environment University of Chinese Academy of SciencesBeijing 100049China Jillin Provincial Joint Laboratory of Changbai Mountain Wetland and Ecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Jillin Jianzhu University Changchun 130118China

The classification of township development types is an urgent problem that requires solution to enable the township to choose an appropriate development *** a township development classification method,we determine the township development types and their spatial patterns in Liaoning Province,*** results showed that the patterns of township development types based on their general advantages had significant spatial *** planting,and livestock and poultry breeding township development types based on general advantages were mainly distributed across the central plain of Liaoning Province,China,and also concentrated in Dandong City−Dalian City along Yellow Sea coast,and in the northwest of Chaoyang *** business and tourism,industry and mining,and residence township development types based on general advantages were distributed mainly along the Shenyang–Dalian Economic Belt in the central and southern Liaoning *** ecology township development type based on general advantages was mainly distributed in the eastern and western Liaoning Province to maintain regional ecological *** development types based on non-advantages were sporadically distributed in the middle and western Liaoning *** on the classification and spatial patterns,the differences between the distribution of twonship development types and the plan for the major functional areas of Liaoning Province were proposed which could provide the basis for the optimization of the major functional areas.

关键词： general advantage township development type spatial pattern Liaoning Province,China

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Spatiotemporal Changes of Snow Depth in Western Jilin,China from 1987 to 2018

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Chinese Geographical Science 2024年第2期34卷 357-368页

作者： WEI Yanlin LI Xiaofeng GU Lingjia zheng Zhaojun zheng xingming JIANG Tao Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchun 130102China College of Electronic Science and Engineering Jilin UniversityChangchun 130012 National Meteorological Satellite Meteorological Center Beijing 100081China

Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming ***,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse ***,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD *** results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/*** snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air *** correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and *** March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo ***,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.

关键词： snow cover snow depth(SD) climate changes passive microwave(PMW) western Jilin,China

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A novel fine-resolution snow depth retrieval model to revealdetailed spatiotemporal patterns of snow cover in NortheastChina

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International Journal of Digital Earth 2023年第1期16卷 1164-1185页

作者： Yanlin Wei Xiaofeng Li Lingjia Gu xingming zheng Tao Jiang Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchunPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchunPeople’s Republic of China College of Electronic Science&Engineering Jilin UniversityChangchunPeople’s Republic of China

Seasonal snow cover is a key component of the global climate and hydrological system,it has drawn considerable attention under global warming *** several passive microwave(PMW)snow depth(SD)products have been developed since the 1970s,they inherit noticeable errors and uncertainties when representing spatial distributions and temporal changes of SD,especially in complex mountainous *** this paper,we developed afine-resolution SD retrieval model(FSDM)using machine learning to improve SD estimation quality for Northeast China and produced a long-term,fine-resolution,daily SD *** accuracies of the FSDM dataset were evaluated against in-situ SD data along with existing SD *** results showed the FSDM dataset provided satisfactory inversion accuracy in spatiotemporal evaluation,with the root-mean-square error(RMSE),bias,and correlation coefficient(R)of 7.10 cm,-0.13 cm,and ***,we analyzed the spatiotemporal variations of SD in Northeast China and found that snow cover was mainly distributed in the Greater Khingan Range,Lesser Khingan Mountains,and Changbai Mountain *** SD exhibited high-low distribution patterns with the increased *** annual mean SD slightly increased at the rate of 0.029 cm/year during 1987-2018.

关键词： Passive microwave remote sensing snow depth inversion machine learning fine resolution Northeast China

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Effects of Snow Cover on Ground Thermal Regime： A Case Study in Heilongjiang Province of China

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Chinese Geographical Science 2016年第4期26卷 527-538页

作者： LI Xiaofeng zheng xingming WU Lili ZHAO Kai JIANG Tao GU Lingjia Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130102 China Changchun Jingyuetan Remote Sensing Test Station Chinese Academy of Sciences Changchun 130117 China University of Chinese Academy of Sciences Beijing 100049 China College of Electronic Science & Engineering Jilin University Changchun 130012 China

The important effects of snow cover to ground thermal decades. In the most of previous research, the effects were usually regime has received much attention of scholars during the past few evaluated through the numerical models and many important results are found. However, less examples and insufficient data based on field measurements are available to show natural cases. In the present work, a typical case study in Mohe and Beijicun meteorological stations, which both are located in the most northern tip of China, is given to show the effects of snow cover on the ground thermal regime. The spatial （the ground profile） and time series analysis in the extremely snowy winter of 2012-2013 in Heilongjiang Province are also performed by contrast with those in the winter of 2011-2012 based on the measured data collected by 63 meteorological stations, Our results illustrate the positive （warmer） effect of snow cover on the ground temperature （GT） on the daily basis, the highest difference between GT and daily mean air temperature （DGAT） is as high as 32.35℃. Moreover, by the lag time analysis method it is found that the response time of GT from 0 cm to 20 cm ground depth to the alternate change of snow depth has 10 days lag, while at 40 cm depth the response of DGAT is not significant. This result is different from the previous research by modeling, in which the resnonse denth of ground to the alteration of snow depth is far more than 40 cm.

关键词： snow cover ground temperature lag time analysis spline mean difference between ground temperature and air temperature(DGAT)

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Predicting Surface Roughness and Moisture of Bare Soils Using Multi- band Spectral Reflectance Under Field Conditions

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Chinese Geographical Science 2018年第6期28卷 986-997页

作者： CHEN Si ZHAO Kai JIANG Tao LI Xiaofeng zheng xingming WAN Xiangkun ZHAO Xiaowei Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130102 China University of Chinese Academy of Sciences Beijing 100049 China College of Geoexploration Science and Technology Jilin University Changchun 130026 China

Soil surface roughness, denoted by the root mean square height(RMSH), and soil moisture(SM) are critical factors that affect the accuracy of quantitative remote sensing research due to their combined influence on spectral reflectance(SR). In regards to this issue, three SM levels and four RMSH levels were artificially designed in this study; a total of 12 plots was used, each plot had a size of 3 m × 3 m. Eight spectral observations were conducted from 14 to 30 October 2017 to investigate the correlation between RMSH, SM, and SR. On this basis, 6 commonly used bands of optical satellite sensors were selected in this study, which are red(675 nm), green(555 nm), blue(485 nm), near infrared(845 nm), shortwave infrared 1(1600 nm), and shortwave infrared 2(2200 nm). A negative correlation was found between SR and RMSH, and between SR and SM. The bands with higher coefficient of determination R^2 values were selected for stepwise multiple nonlinear regression analysis. Four characterized bands(i.e., blue, green, near infrared, and shortwave infrared 2) were chosen as the independent variables to estimate SM with R^2 and root mean square error(RMSE) values equal to 0.62 and 2.6%, respectively. Similarly, the four bands(green, red, near infrared, and shortwave infrared 1) were used to estimate RMSH with R^2 and RMSE values equal to 0.48 and 0.69 cm, respectively. These results indicate that the method used is not only suitable for estimating SM but can also be extended to the prediction of RMSH. Finally, the evaluation approach presented in this paper highly restores the real situation of the natural farmland surface on the one hand, and obtains high precision values of SM and RMSH on the other. The method can be further applied to the prediction of farmland SM and RMSH based on satellite and unmanned aerial vehicle(UAV) optical imagery.

关键词： soil surface roughness soil moisture spectral reflectance field conditions stepwise multiple nonlinear regression

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An investigation on microwave transmissivity at frequencies of 18.7 and 36.5 GHz for diverse forest types during snow season

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International Journal of Digital Earth 2021年第10期14卷 1354-1379页

作者： Wang Guangrui Li Xiaofeng Chen Xiuxue Jiang Tao zheng xingming Wei Yanlin Wan Xiangkun Wang Jian Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchunPeople’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijingPeople’s Republic of China Changchun Jingyuetan Remote Sensing Experiment Station Chinese Academy of SciencesChangchunPeople’s Republic of China School of Statistics Dongbei University of Finance and EconomicsDalianPeople’s Republic of China

Forests have invariably been considered as an obstacle in retrieving land surface parameters from spaceborne passive microwave brightness temperature(T_(B))*** quantifying the effect of forests on microwave signals,several models have been ***,these models rarely reveal the dependence of microwave radiation on forest types,which can hardly meet the needs of high-accuracy retrieval of terrestrial parameters in forested regions.A ground-based microwave radiometric observation experiment was designed to investigate the dependence of microwave radiation on frequency,polarization,and forest *** TB at 18.7-and 36.5-GHz for horizontal-and vertical-polarization from the forest canopy was measured at 14 sample plots in Northeast China,along with snowpack and forest structural *** providing fits to experimental data,new empirical transmissivity models for three forest types were developed,as a function of woody stem volume and depending on the frequency/*** proposed models give diverse asymptotic transmissivity saturation levels and the corresponding saturation point of woody stem volume for different forest ***-mean-square error results between T_(B) simulations and Advanced Microwave Scanning Radiometer-2 observations are approximately 3-6 *** study provides an experimental and theoretical reference for further development of inversion models for snow parameters in forested areas.

关键词： Forest transmissivity snow woody stem volume microwave radiometry HUT

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A Cloud Framework for High Spatial Resolution Soil Moisture Mapping from Radar and Optical Satellite Imageries

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Chinese Geographical Science 2023年第4期33卷 649-663页

作者： GUO Tianhao zheng Jia WANG Chunmei TAO Zui zheng xingming WANG Qi LI Lei FENG Zhuangzhuang WANG Xigang LI Xinbiao KE Liwei Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Changchun Jingyuetan Remote Sensing Test Site Changchun 130102China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China China Centre for Resources Satellite Data and Application China Aerospace Science and Technology CorporationBeijing 100094China College of Geoexploration Science and Technology Jilin UniversityChangchun 130026China School of Geomatics and Prospecting Engineering Jilin Jianzhu UniversityChangchun 130118China

Soil moisture plays an important role in crop yield estimation,irrigation management,*** sensing technology has potential for large-scale and high spatial soil moisture ***,offline remote sensing data processing is time-consuming and resource-intensive,and significantly hampers the efficiency and timeliness of soil moisture *** to the high-speed computing capabilities of remote sensing cloud platforms,a High Spatial Resolution Soil Moisture Estimation Framework(HSRSMEF)based on the Google Earth Engine(GEE)platform was developed in this *** functions of the HSRSMEF include research area and input datasets customization,radar speckle noise filtering,optical-radar image spatio-temporal matching,soil moisture retrieving,soil moisture visualization and *** paper tested the performance of HSRSMEF by combining Sentinel-1,Sentinel-2 images and insitu soil moisture data in the central farmland area of Jilin Province,*** Normalized Difference Vegetation Index(NDVI)based on the Savitzky-Golay algorithm conforms to the crop growth cycle,and its correlation with the original NDVI is about 0.99(P<0.001).The soil moisture accuracy of the random forest model(R 2=0.942,RMSE=0.013 m3/m3)is better than that of the water cloud model(R 2=0.334,RMSE=0.091 m3/m3).HSRSMEF transfers time-consuming offline operations to cloud computing platforms,achieving rapid and simplified high spatial resolution soil moisture mapping.

关键词： soil moisture(SM) Google Earth Engine(GEE) Cloud Computing Platform High Spatial Resolution Soil Moisture Estimation Framework(HSRSMEF) remote sensing Sentienl-1 Sentinel-2 Northeast China

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Rapid Diagnosis with FISH for Chromosomal Abnormality of Fetal Pyelectasia

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Wuhan University Journal of Natural Sciences 2008年第2期13卷 252-256页

作者： HUANG Fenghua zheng xingming ZHANG Yuanzheng XIAOLiping LIN Li Department of Obstetrics and Gynecology ZhongnanHospital Wuhan University Wuhan 430071 Hubei China Department of Urology Zhongnan Hospital WuhanUniversity Wuhan 430071 Hubei China

Fluorescence in situ Hybridization （FISH） was used to investigate whether the chromosome of the fetus prenatally diagnosed as pyelectasis was normal or not. Amniotic fluid was taken from the pregnant woman whose fetus was detected with pyelectasia by prenatal examination. The chromosome of the amniotic fluid cell without culture was examined with FISH. The result shows that compared with the traditional amniotic fluid cell culture, FISH has the advantages of more rapid, higher sensitivity and specificity, and was 10-12 days earlier to complete the diagnosing than the traditional method. The fetuses detected chromosomal abnormality in each groups were induced during the middle and late trimester, while those fetuses with normal chromosome continued pregnancy, the rate of spontaneous disappearance of pyelectasia decreased as the severity of pyelectasia increased. FISH can satisfy the urgent need in the clinical prenatal diagnosis due to its rapidity to determine whether fetus with pyelectasia was accompanied with chromosomal.

关键词： fluorescence in situ hybridization fetus pyelectasia chromosomal abnormality amniotic fluid cell

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