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Comparison of surface water extraction performances of different classic water indices using OLI and TM imageries in different situations

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Geo-Spatial Information Science 2015年第1期18卷 32-42页

作者： Ke ZHAI Xiaoqing WU yuanwei qin Peipei DU Yantai Institute of Coastal Zone Research Chinese Academy of Sciences17 Chunhui RoadYantai264003China Department of Microbiology and Plant Biology Center for Spatial AnalysisUniversity of OklahomaNormanOklahomaUSA University of Chinese Academy of Sciences 19 Yuquan RoadBeijing100049China

Recently,water extraction based on the indices method has been documented in many studies using various remote sensing data *** them,Landsat satellites data have certain advantages in spatial resolution and *** the successful launch of Landsat 8,the Operational Land Imager(OLI)data from the satellite are getting more and more attention because of its new *** this study,we used the OLI imagery data source to study the water extraction performance based on the Normalized Difference Vegetation Index,Normalized Difference Water Index,Modified Normalized Water Index(MNDWI),and Automated Water Extraction Index(AWEI)and compared the results with the Thematic Mapper(TM)imagery *** test sites in Tianjin City of north China were selected as the study area to verify the applicability of OLI data and demonstrate its advantages over TM *** found that the results of surface water extraction based on OLI data are slightly better than that based on TM in the two test sites,especially in the city *** AWEI and MNDWI indices performs better than the other two indices,and the thresholds of water indices show more stability when using the OLI ***,it is suitable to combine OLI imagery with other Landsat sensor data to study water changes for long periods of time.

关键词： water extraction operational land imager(OLI)data threshold stability water indices

Mapping paddy rice distribution using multi-temporal Landsat imagery in the Sanjiang Plain, northeast China

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Frontiers of Earth Science 2016年第1期10卷 49-62页

作者： Cui JIN Xiangming XIAO Jinwei DONG yuanwei qin Zongming WANG Department of Microbiology and Plant Biology Center for Spatial Analysis University of Oklahoma Norman OK 73019 USA Institute of Biodiversity Sciences Fudan University Shanghai 200433 China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130102 China

Information of paddy rice distribution is essential for food production and methane emission calculation. Phenology-based algorithms have been uti- lized in the mapping of paddy rice fields by identifying the unique flooding and seedling transplanting phases using multi-temporal moderate resolution （500m to 1 km） images. In this study, we developed simple algorithms to identify paddy rice at a fine resolution at the regional scale using multi-temporal Landsat imagery. Sixteen Landsat images from 2010-2012 were used to generate the 30 m paddy rice map in the Sanjiang Plain, northeast China-one of the major paddy rice cultivation regions in China. Three vegetation indices, Normalized Difference Vegetation Index （NDVI）, Enhanced Vegetation Index （EVI）, and Land Surface Water Index （LSWI）, were used to identify rice fields during the flooding/transplanting and ripening phases. The user and producer accuracies of paddy rice on the resultant Landsat-based paddy rice map were 90% and 94%, respectively. The Landsat-based paddy rice map was an improvement over the paddy rice layer on the National Land Cover Dataset, which was generated through visual interpretation and digitalization on the fine-resolution images. The agricultural census data substantially underreported paddy rice area, raising serious concern about its use for studies on food security.

关键词： phenology flooding transplanting ripening,land use

Impacts of ecological restoration projects on agricultural productivity in China

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Journal of Geographical Sciences 2013年第3期23卷 404-416页

作者： qin yuanwei YAN Huimin LIU Jiyuan DONG Jinwei CHEN Jingqing XIAO Xiangming Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Departments of Microbiology and Plant Botany Center for Spatial Analysis University of Oklahoma Norman Oklahoma 73019-5300 USA

The changes in cropland quantity and quality due to land use are critical concerns to national food security, particularly for China. Despite the significant ecological effects, the ecological restoration program （ERP）, started from 1999, has evidently altered the spatial patterns of China＇s cropland and agricultural productivity. Based on cropland dynamic data from 2000 to 2008 primarily derived from satellite images with a 30-m resolution and satel- lite-based net primary productivity models, we identified the impacts on agricultural produc- tivity caused by ERP, including ＂Grain for Green＂ Program （GFGP） and ＂Reclaimed Cropland to Lake＂（RCTL） Program. Our results indicated that the agricultural productivity lost with a rate of 132.67×104 t/a due to ERP, which accounted for 44.01% of the total loss rate caused by land use changes during 2000-2005. During 2005-2008, the loss rate due to ERP de- creased to 77.18×104 t/a, which was equivalent to 58.17% of that in the first five years and 30.22% of the total loss rate caused by land use changes. The agricultural productivity loss from 2000-2008 caused by ERP was more attributed to GFGP （about 70%） than RCTL. Al- though ERP had a certain influence on cropland productivity during 2000-2008, its effect was still much less than that of urbanization; moreover, ERP was already converted from the project implementation phase to the consolidation phase.

关键词： ecological restoration agricultural productivity remote sensing Grain for Green Reclaimed Croplland to Lake

Continued Increases of Gross Primary Production in Urban Areas during 2000-2016

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Journal of Remote Sensing 2022年第1期2022卷 98-111页

作者： Yaoping Cui Xiangming Xiao Jinwei Dong Yao Zhang yuanwei qin Russell BDoughty Xiaocui Wu Xiaoyan Liu Joanna Joiner Berrien Moore III Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475001China School of Geography And Environmental Science Henan UniversityKaifeng 475004China Department of Microbiology and Plant Biology Center for Earth Observation and ModelingUniversity of OklahomaNormanOKUSA Institute of Geographical Sciences and Resources Chinese Academy of SciencesBeijing 100101China College of Atmospheric and Geographic Sciences University of OklahomaOK 73019USA Agroecosystem Sustainability Center Institute for SustainabilityEnergyAnd EnvironmentUniversity of Illinois Urbana-ChampaignUrbanaIL 61801USA NASA Goddard Space Flight Center GreenbeltMD 20771USA

Urbanization affects vegetation within city administrative boundary and nearby rural *** primary production(GPP)of vegetation in global urban areas is one of important metrics for assessing the impacts of urbanization on terrestrial *** date,very limited data and information on the spatial-temporal dynamics of GPP in the global urban areas are *** this study,we reported the spatial distribution and temporal dynamics of annual GPP during 2000–2016 from 8,182 gridcells(0.5°by 0.5°latitude and longitude)that have various proportion of urban *** 79.3%of these urban gridcells had increasing trends of annual GPP during *** urban area proportion(%)within individual urban gridcells increased,the means of annual GPP trends also *** results suggested that for those urban gridcells,the negative effect of urban expansion(often measured by impervious surfaces)on GPP was to large degree compensated by increased vegetation within the gridcells,mostly driven by urban management and local climate and *** findings on the continued increases of annual GPP in most of urban gridcells shed new insight on the importance of urban areas on terrestrial carbon cycle and the potential of urban management and local climate and environment on improving vegetation in urban areas.

关键词： Urbanization urban continued

Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s

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Journal of Geographical Sciences 2014年第2期24卷 195-210页

作者： LIU Jiyuan KUANG Wenhui ZHANG Zengxiang XU Xinliang qin yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Institute of Remote Sensing and Digital Earth CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Chengdu Institute of Mountain Hazards and Environment CAS Chengdu 610041 China Northeast Institute of Geography and Agricultural Ecology CAS Changchun 130012 China Wuhan Institute of Geodesy and Geophysics CAS Wuhan 430077 China Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China Xinjiang Institute of Ecology and Geography CAS Urumqi 830011 China Institute of Soil Science CAS Nanjing 210008 China Nanjing Institute of Geography and Limnology CAS Nanjing 210008 China

Land-use/land-cover changes （LUCCs） have links to both human and nature inter- actions. China＇s Land-Use/cover Datasets （CLUDs） were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM／ETM＋ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes （LUCs） across China indicated a significant variation in spatial and temporal characteristics in the last 20 years （1990-2010）. The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included （1） an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; （2） shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; （3） continuous transformation from rain-fed farmlands in northeast China to paddy fields; and （4） effective- ness of the ＂Grain for Green＂ project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate

关键词： satellite remote sensing land-use change characteristics spatial pattern China

Annual Maps of Forests in Australia from Analyses of Microwave and Optical Images with FAO Forest Definition

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Journal of Remote Sensing 2021年第1期2021卷 134-144页

作者： yuanwei qin Xiangming Xiao Jean-Pierre Wigneron Philippe Ciais Josep G.Canadell Martin Brandt Xiaojun Li Lei Fan Xiaocui Wu Hao Tang Ralph Dubayah Russell Doughty qing Chang Sean Crowell Bo Zheng Kevin Neal Jorge A.Celis Berrien MooreⅢ Department of Microbiology and Plant Biology Center for Earth Observation and ModelingUniversity of OklahomaNormanOK 73019USA ISPA UMR 1391INRA Nouvelle-AquitaineBordeaux Villenave d’OrnonFrance Laboratoire des Sciences du Climat et de l'Environnement LSCE/IPSLCEA-CNRS-UVSQUniversitéParis-Saclay91191 Gif-sur-YvetteFrance CSIRO Oceans and Atmosphere CanberraACTAustralia Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Department of Geography National University of Singapore1 Arts LinkKent RidgeSingapore 117570 Department of Geographical Sciences University of MarylandCollege ParkMDUSA Division of Geological and Planetary Sciences California Institute of TechnologyPasadenaCA 91125USA O’Neill School of Public and Environmental Affairs Indiana University Bloomington702 N Walnut Grove AveBloomingtonIN 47405USA College of Atmospheric and Geographic Sciences University of OklahomaNormanOK 73019USA Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

The Australian governmental agencies reported a total of 149 million ha forest in the Food and Agriculture Organization of the United Nations(FAO)in 2010,ranking sixth in the world,which is based on a forest definition with tree height>2 ***,we report a new forest cover data product that used the FAO forest definition(tree cover>10%and tree height>5 meters at observation time or mature)and was derived from microwave(Phased Array type L-band Synthetic Aperture Radar,PALSAR)and optical(Moderate Resolution Imaging Spectroradiometer,MODIS)images and validated with very high spatial resolution images,Light Detection and Ranging(LiDAR)data from the Ice,Cloud,and land Elevation Satellite(ICESat),and in situ field survey *** new PALSAR/MODIS forest map estimates 32 million ha of forest in 2010 over ***/MODIS forest map has an overall accuracy of~95%based on the reference data derived from visual interpretation of very high spatial resolution images for forest and nonforest cover *** with the canopy height and canopy coverage data derived from ICESat LiDAR strips,PALSAR/MODIS forest map has 73%of forest pixels meeting the FAO forest definition,much higher than the other four widely used forest maps(ranging from 36%to 52%).PALSAR/MODIS forest map also has a reasonable spatial consistency with the forest map from the National Vegetation Information *** new annual map of forests in Australia could support cross-country comparison when using data from the FAO Forest Resource Assessment Reports.

关键词： forest Forest PALSAR

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21世纪初中国土地利用强度的空间分布格局

地理学报 2016年第7期71卷 1130-1143页

作者：刘芳闫慧敏刘纪远肖向明秦元伟中国科学院地理科学与资源研究所北京100101 美国俄克拉荷马大学微生物与植物生物系空间分析中心俄克拉荷马诺曼73019 复旦大学生物多样性科学研究所上海200433

土地利用强度直接反映了人类活动对自然生态系统的影响程度,成为全球环境变化的重要驱动力,也是土地利用可持续程度的重要测度指标。当前土地科学研究主要关注土地覆被变化及其对生态环境的影响,而土地利用强度的高分辨率时空表达尚在... 详细信息

土地利用强度直接反映了人类活动对自然生态系统的影响程度,成为全球环境变化的重要驱动力,也是土地利用可持续程度的重要测度指标。当前土地科学研究主要关注土地覆被变化及其对生态环境的影响,而土地利用强度的高分辨率时空表达尚在探索阶段。本文基于土地利用栅格成分数据、遥感数据、社会经济数据等空间化指标要素,根据地表被人类活动干扰程度及其可逆性分为人工地类、半人工地类、半天然地类、天然地类4个一级类型;依据耕作强度、人口密度等人类活动强度指标分为22个二级类型,获得空间分辨率为1 km的中国土地利用强度图。21世纪初全国人工地类、半人工地类、半天然地类和天然地类的面积比例分别为0.71%、19.36%、58.93%和21%,人口分布密集的东南部土地利用强度类型多样,且整体高于人口稀疏的西北部;随着经度的增加,土地利用强度类型由以天然地类和半天然地类为主转变为半天然地类和半人工地类为主;东部省市区土地利用强度高于中、西部,西部省市区土地利用强度最低;土地利用强度类型呈区域性集聚分布。与已有研究相比,该研究有效刻画了中国土地利用强度的空间异质性,有助于深入理解人类与自然生态系统的交互格局及其生态环境效应,为可持续土地利用政策的制定提供科学依据。

关键词：土地利用强度分类系统空间分异可持续性中国

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中国森林覆盖度产品的差异性及不确定性分析

生物多样性 2015年第6期23卷 830-834页

作者：秦元伟董金玮肖向明俄克拉荷马大学微生物与植物生物系、空间分析中心美国诺曼俄克拉荷马73019 复旦大学生物多样性科学研究所中国上海200433

森林具有气候调节、水源涵养、生物多样性保护等诸多生态服务功能（Millennium Ecosystem Assessment,2005;van der Werf et al.,2009）,同时减少毁林和森林退化也是减缓温室气体排放协议REDD＋的重要内容（DeF ries et al.,2007;Grassi... 详细信息

森林具有气候调节、水源涵养、生物多样性保护等诸多生态服务功能（Millennium Ecosystem Assessment,2005;van der Werf et al.,2009）,同时减少毁林和森林退化也是减缓温室气体排放协议REDD＋的重要内容（DeF ries et al.,2007;Grassi et al.,2008）。为了改善日益恶化的生态状况,提高森林资源的蓄积量,自20世纪70年代以来,中国实施了六大林业重点工程,包括天然林保护工程、“三北”和长江中下游地区等重点防护林体系建设工程、退耕还林还草工程、京津风沙源治理工程、野生动植物保护及自然保护区建设工程以及重点地区速生丰产用材林为主的林业产业建设工程。在森林砍伐和林业工程的双向驱动下，如何准确地监测中国森林覆盖度及其时空变化成为一大挑战。

关键词：天然林保护 Millennium 毁林生物多样性保护气体排放不确定性分析水源涵养野外调查数据遥感数据数据空间

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美国军事高等教育思想管窥

高等教育研究学报 2003年第2期26卷 13-15页

作者：秦元伟国防科技大学高等教育研究室硕士研究生410073

本文从斯巴达教育和雅典教育的创造性整合、科学教育与人文教育的有机融合两个方面对美国军事高等教育思想作了初步探讨,并从中得出对我国军事高等教育的启示。

关键词：军事高等教育思想