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Construction of lake bathymetry from MODIS satellite data and GIS from 2003 to 2011

Chinese Journal of Oceanology and Limnology 2014年第3期32卷 720-731页

作者：严翼肖飞杜耘 University of Chinese Academy of Sciences Institute of Geodesy and Geophysics Chinese Academy of SciencesKey Laboratory for Environment and Disaster Monitoring and Evaluation

In recent years, sedimentation conditions in Dongting Lake have varied greatly because of signifi cant changes in runoff and sediment load in the Changjiang(Yangtze) River following the construction of Three Gorges Dam. The topography of the lake bottom has changed rapidly because of the intense exchange of water and sediment between the lake and the Changjiang River. However, time series information on lake-bottom topographic change is lacking. In this study, we introduced a method that combines remote sensing data and in situ water level data to extract a record of Dongting Lake bottom topography from 2003 to 2011. Multi-temporal lake land/water boundaries were extracted from MODIS images using the linear spectral mixture model method. The elevation of water/land boundary points were calculated using water level data and spatial interpolation techniques. Digital elevation models of Dongting Lake bottom topography in different periods were then constructed with the multiple heighted waterlines. The mean root-mean-square error of the linear spectral mixture model was 0.036, and the mean predicted error for elevation interpolation was-0.19 m. Compared with fi eld measurement data and sediment load data, the method has proven to be most applicable. The results show that the topography of the bottom of Dongting Lake has exhibited uneven erosion and deposition in terms of time and space over the last nine years. Moreover, lake-bottom topography has undergone a slight erosion trend within this period, with 58.2% and 41.8% of the lake-bottom area being eroded and deposited, respectively.

关键词： MODIS影像地理信息系统水深卫星数据线性光谱混合模型湖泊数字高程模型空间插值技术

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Topography and soil content contribute to plant community composition and structure in subtropical evergreen-deciduous broadleaved mixed forests

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Plant Diversity 2021年第4期43卷 264-274页

作者： Qichi Yang Hehe Zhang Lihui Wang Feng Ling Zhengxiang Wang Tingting Li Jinliang Huang key laboratory for environment and disaster monitoring and evaluation HubeiInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430077China University of Chinese Academy of Sciences Beijing100049China School of Resource and environment Hubei UniversityWuhan430062China

Topography and soil factors are known to play crucial roles in the species composition of plant communities in subtropical evergreen-deciduous broadleaved mixed forests.In this study,we used a systematic quantitative approach to classify plant community types in the subtropical forests of Hubei Province(central China),and then quantified the relative contribution of drivers responsible for variation in species composition and diversity.We classified the subtropical forests in the study area into 12 community types.Of these,species diversity indices of three communities were significantly higher than those of others.In each community type,species richness,abundance,basal area and importance values of evergreen and deciduous species were different.In most community types,deciduous species richness was higher than that of evergreen species.Linear regression analysis showed that the dominant factors that affect species composition in each community type are elevation,slope,aspect,soil nitrogen content,and soil phosphorus content.Furthermore,structural equation modeling analysis showed that the majority of variance in species composition of plant communities can be explained by elevation,aspect,soil water content,litterfall,total nitrogen,and total phosphorus.Thus,the major factors that affect evergreen and deciduous species distribution across the 12 community types in subtropical evergreendeciduous broadleaved mixed forests include elevation,slope and aspect,soil total nitrogen content,soil total phosphorus content,soil available nitrogen content and soil available phosphorus content.

关键词： environmental factors Plant community Two-way indicator species analysis Detrended correspondence analysis Evergreen-deciduous broadleaved mixed forests Northwestern of Hubei

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Development of a multi-view and geo-event-driven real-time collaborative GIS

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International Journal of Digital Earth 2022年第1期15卷 134-147页

作者： Sun Yaqin Xu Chen Wu Jinxiong Yuan Hang Shi Haibo Zhan Xiumei Zhang Lin key laboratory of Land environment and disaster monitoring MNR China University of Mining and TechnologyXuzhouPeople’s Republic of China College of Surveying and GeoInformatics Tongji UniversityShanghaiPeople’s Republic of China

Supporting distributed real-time collaborative work has become an important development trend in GIS.It enables group users to cooperate and improve the use of scientific data and collaboration technologies.Real-time collaborative GIS(RCGIS)provides a platform for supporting synchronous collaboration using geospatial data in various forms.Traditional RCGIS generally works on a single map view,which has the disadvantage of collaborative interface confusion.The traditional system-driven mechanism of RCGIS is a computer-interaction event that has the disadvantage of an unfriendly collaborative perception.This paper presents a design and prototype of a RCGIS based on multi-view and geo-event driven mechanisms.The geo-event-driven mechanism provides users with a smoother collaborative perception and interactions that are more natural and friendly.The collaboration process for a GIS that is driven by geo-events is also discussed.A multi-view technique is used to make real-time GIS collaboration more orderly.The paper also proposes a synchronization strategy for public–private views.Finally,walk-through examples are used to demonstrate the use of RCGIS within a web environment.

关键词： Geographical information collaboration real-time multi-view geo-event driven

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Observational Subseasonal Variability of the PM_(2.5) Concentration in the Beijing-Tianjin-Hebei Area during the January 2021 Sudden Stratospheric Warming

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Advances in Atmospheric Sciences 2022年第10期39卷 1623-1636页

作者： Qian LU Jian RAO Chunhua SHI Dong GUO Ji WANG Zhuoqi LIANG Tian WANG key laboratory of Meteorological disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjing 210044China key laboratory of Meteorology and Ecological environment of Hebei Province Shijiazhuang 050021China Beijing Regional Climate Center Beijing 100089China

It is still not well understood if subseasonal variability of the local PM_(2.5) in the Beijing-Tianjin-Hebei(BTH)region is affected by the stratospheric state.Using PM_(2.5) observations and the ERA5 reanalysis,the evolution of the air quality in BTH during the January 2021 sudden stratospheric warming(SSW)is explored.The subseasonal variability of the PM_(2.5) concentration after the SSW onset is evidently enhanced.Stratospheric circumpolar easterly anomalies lasted for 53 days during the January-February 2021 SSW with two evident stratospheric pulses arriving at the ground.During the tropospheric wave weakening period and the intermittent period of dormant stratospheric pulses,the East Asian winter monsoon weakened,anomalous temperature inversion developed in the lower troposphere,anomalous surface southerlies prevailed,atmospheric moisture increased,and the boundary layer top height lowered,all of which favor the accumulation of pollutant particulates,leading to two periods of pollution processes in the BTH region.In the phase of strengthened East Asian winter monsoon around the very beginning of the SSW and another two periods when stratospheric pulses had reached the near surface,opposite-signed circulation patterns and meteorological conditions were observed,which helped to dilute and diffuse air pollutants in the BTH region.As a result,the air quality was excellent during the two periods when the stratospheric pulse had reached the near surface.The increased subseasonal variation of the regional pollutant particulates after the SSW onset highlights the important role of the stratosphere in the regional environment and provides implications for the environmental prediction.

关键词： sudden stratospheric warming(SSW) PM_(2.5) Beijing-Tianjin-Hebei(BTH) East Asian winter monsoon boundary layer meteorological conditions

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Inconsistent seasonal variation of antibiotics between surface water and groundwater in the Jianghan Plain:Risks and linkage to land uses

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Journal of environmental Sciences 2021年第11期33卷 102-113页

作者： Xi Liu Zhi Wang Lu Zhang Weiying Fan Chao Yang Enhua Li Yun Du Xuelei Wang key laboratory for environment and disaster monitoring and evaluation of Hubei Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China University of Chinese Academy of Sciences Beijing 100049China Honghu Lake Station for Wetland Ecosystem Research Chinese Academy of SciencesHonghu 433200China

Antibiotics are widely used in humans and animals,but their transformation from surface water to groundwater and the impact of land uses on them remain unclear.In this study,14 antibioticswere systematically surveyed in a complex agricultural area in Central China.Results indicated that the selected antibiotic concentrations in surface waters were higher in winter(average:32.7 ng/L)than in summer(average:17.9 ng/L),while the seasonal variation in groundwaters showed an opposite trend(2.2 ng/L in dry winter vs.8.0 ng/L in summer).Macrolides were the predominant antibiotics in this area,with a detected frequency of over 90%.A significant correlation between surface water and groundwater antibiotics was only observed in winter(R^(2)=0.58).This study further confirmed the impact of land uses on these contaminants,with optimal buffer radii of 2500 m in winter and 500 m in summer.Risk assessment indicated that clarithromycin posed high risks in this area.Overall,this study identified the spatiotemporal variability of antibiotics in a typical agricultural area in Central China and revealed the impact of land uses on antibiotic pollution in aquatic environments.

关键词： Antibiotic pollution Risk assessment Optimal buffer Land use Honghu Lake

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Combined multi-kernel support vector machine and wavelet analysis for hyperspectral remote sensing image classification

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Chinese Optics Letters 2011年第1期9卷 45-48页

作者：谭琨杜培军 key laboratory for Land environment and disaster monitoring of State Bureau of Surveying and Mapping of China China University of Mining and Technology

Many remote sensing image classifiers are limited in their ability to combine spectral features with spatial features. Multi-kernel classifiers, however, are capable of integrating spectral features with spatial or structural features using multiple kernels and summing them for final outputs. Using a support vector machine （SVM） as classifier, different multi-kernel classifiers are constructed and tested using 64-band Operational Modular Imaging Spectrometer II hyperspectral image of Changping Area, Beijing City. Results show that by integrating spectral and wavelet texture information, multi-kernel SVM classifiers can obtain more accurate classification results than sole-kernel SVM classifiers and cross-information SVM kernel classifiers. Moreover, when the multi-kernel SVM classifier is used, the combination of the first four principal components from principal component analysis and wavelet texture provides the highest accuracy （97.06%）. Multi-kernel SVM is therefore an effective approach to improve the accuracy of hyperspectral image classification and to expand possibilities for remote sensing image interpretation and application.

关键词： Image analysis Image classification Image reconstruction Remote sensing Support vector machines Textures Wavelet analysis

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Simulated impacts of atmospheric gravity waves on the initiation and optical emissions of sprite halos in the mesosphere

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Science China Earth Sciences 2019年第4期62卷 631-642页

作者： Jinbo ZHANG Qilin ZHANG Xiufeng GUO Wenhao HOU Haiyang GAO key laboratory of Meteorological disaster Ministry of Education (KLME) Joint International Research Laboratory of Climate and Environment Change (ILCEC) Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster (CIC-FEMD) Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science & Technology

The correlation between atmospheric gravity waves(GWs) and Transient Luminous Events(TLEs) has been poorly studied using both synchronous observations and numerical simulations. To investigate the modulation effects of GWs on TLEs,a troposphere-mesosphere quasi-electrostatic field model is developed in three-dimensional Cartesian coordinates, and the effects of GW perturbations on the initiation and optical emissions of sprite halos are simulated using the model. Simulation results indicate that the atmospheric density at lower ionosphere altitudes becomes inhomogeneous due to GW perturbations, and sprite halos tend to initiate in the GW troughs due to the lower electric breakdown threshold. GW perturbations cause the deformation of sprite halos, strong luminous regions distribute mainly along the GW troughs while optical intensities along the GW peaks is relatively weak. Larger GW perturbations lead to more pronounced deformation of sprite halos, however, stronger lightning discharges in the troposphere result in less optical perturbations of sprite halos. The observed luminous intensities and optical morphology of sprite halos are also affected by the observing orientations and the lightning polarities.

关键词： Three-dimensional quasi-electrostatic field model Sprite halos Optical emission Gravity waves

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Land subsidence monitoring by D-InSAR technique

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Mining Science and Technology 2011年第6期21卷 869-872页

作者： Fan Hongdong Deng Kazhong Ju Chengyu Zhu Chuanguang Xue Jiqun China University of Mining ＆ Technology Key Laboratory for Land Environment and Disaster Monitoring of SBSM Xuzhou 221116 China

Nowadays, the researches of using Differential Interferometric Synthetic Aperture Radar (D-InSAR) tech- nique to monitor the land subsidence are mainly on how to qualitatively analyze the subsidence areas and values, but the analysis of subsidence process and mechanism are insufficient. In order to resolve these problems, 6 scenes of ERS1/2 images captured during 1995 and 2000 in a certain place of Jiangsu province were selected to obtain the subsidence and velocities in three time segments by ''two-pass'' D- InSAR method. Then the relationships among distributions of pumping wells, exploitation quantity of groundwater, and confined water levels were studied and the subsidence mechanism was systematically analyzed. The results show that using D-InSAR technique to monitor the deformation of large area can obtain high accuracies, the disadvantages of classical observation methods can be remedied and there is a linear relationship among the velocities of land subsidence, the water level and the exploitation quantity.

关键词： InSAR技术沉降监测干涉合成孔径雷达地下水开采量 D-InSAR 土地地面沉降 INSAR

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Alternation of the Atmospheric Teleconnections Associated with the Northeast China Spring Rainfall during a Recent 60-Year Period

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Advances in Atmospheric Sciences 2023年第1期40卷 168-176页

作者： Zhiwei ZHU Rui LU Shanshan FU Hua CHEN key laboratory of Meteorological disaster Ministry of Education(KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)Nanjing University of Information Science and TechnologyNanjing 210044China

Northeast China(NEC)is China’s national grain production base,and the local precipitation is vital for agriculture during the springtime.Therefore,understanding the dynamic origins of the NEC spring rainfall(NECSR)variability is of socioeconomic importance.This study reveals an interdecadal change in the atmospheric teleconnections associated with the NECSR during a recent 60-year period(1961-2020).Before the mid-1980s,NECSR had been related to a Rossby wave train that is coupled with extratropical North Atlantic sea surface temperature(SST),whereas,since the mid-1980s,NECSR has been linked to a quite different Rossby wave train that is coupled with tropical North Atlantic SST.Both Rossby wave trains could lead to enhanced NECSR through anomalous cyclones over East Asia.The weakening of the westerly jet over North America is found to be mainly responsible for the alternation of the atmospheric teleconnections associated with NECSR during two epochs.

关键词： Northeast China spring rainfall Rossby wave train interdecadal change westerly jet stream

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A Data-Intensive FLAC^3D Computation Model:Application of Geospatial Big Data to Predict Mining Induced Subsidence

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Computer Modeling in Engineering & Sciences 2019年第5期119卷 395-408页

作者： Yaqiang Gong Guangli Guo NASG key laboratory of Land environment and disaster monitoring China University of Mining and TechnologyXuzhou221116China School of environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou221116China

Although big data are widely used in various fields,its application is still rare in the study of mining subsidence prediction(MSP)caused by underground mining.Traditional research in MSP has the problem of oversimplifying geological mining conditions,ignoring the fluctuation of rock layers with space.In the context of geospatial big data,a data-intensive FLAC3D(Fast Lagrangian Analysis of a Continua in 3 Dimensions)model is proposed in this paper based on borehole logs.In the modeling process,we developed a method to handle geospatial big data and were able to make full use of borehole logs.The effectiveness of the proposed method was verified by comparing the results of the traditional method,proposed method,and field observation.The findings show that the proposed method has obvious advantages over the traditional prediction results.The relative error of the maximum surface subsidence predicted by the proposed method decreased by 93.7%and the standard deviation of the prediction results(which was 70 points)decreased by 39.4%,on average.The data-intensive modeling method is of great significance for improving the accuracy of mining subsidence predictions.

关键词： Geospatial big data mining subsidence prediction FLAC3D underground coal mining

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