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Detection of the urban heat island in beijing using HJ-1B satellite imagery

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Science China Earth Sciences 2010年第S1期53卷 67-73页

作者： YANG Jun1,GONG Peng2,ZHOU JinXing3,HUANG HuaBing2 & WANG Lei2 1 Key Laboratory of Silviculture and Conservation,Ministry of Education,beijing forestry University,beijing 100083,China 2 State Key Laboratory of Remote Sensing Science,jointly sponsored by the institute of Remote Sensing Applications,chinese academy of Sciences and beijing Normal University,beijing 100101,China 3.institute of desertification studies,chinese academy of forestry,beijing 100091 China 1. Key Laboratory of Silviculture and Conservation Ministry of Education Beijing Forestry University Beijing 100083 China2. State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China3. Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China

Satellite images are used extensively in studying the urban heat island(UHI) *** evaluated the suitability of thermal infrared(TIR) data from the HJ-1B satellite for detecting UHI using a case study in *** modified algorithms for retrieving the land surface temperature(LST) from HJ-1B data were *** results were compared with LST images derived from a Landsat TM thermal band and the MODIS LST *** spatial pattern of UHI generated using HJ-1B data matched well with that produced using TM and MODIS *** the two algorithms,the mono-window algorithm performed better but further tests are *** more frequent coverage than TM and higher spatial resolution than MODIS,the HJ-1B TIR data present a unique opportunity to study thermal environments in cities in China and neighboring countries.

关键词： surface temperature NDVI mono-window algorithm single-channel algorithm

Rocky Land desertification and its Driving Forces in the Karst Areas of Rural Guangxi,Southwest China

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Journal of Mountain Science 2008年第4期5卷 350-357页

作者： LIU Yansui WANG Jieyong DENG Xiangzheng institute of Geographic Sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China institute of Geographic Sciences and Natural Resources Research Chinese Academy of Science Beijing loolo~ ChinaGraduate University of Chinese Academy of Sciences Beijing 100039 China

With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst *** desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same ***,in turn,has exacerbated the poverty level in the rural areas of the *** this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2000 and *** also analyzed the driving forces of the desertification and its *** constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new *** new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest China,and also for alleviating poverty in the rural areas in the future.

关键词： Rocky land desertification karstmountain area rural poverty driving force Guangxi Southwest China

Change of surface cover greenness in China between 2000 and 2010

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chinese Science Bulletin 2012年第22期57卷 2835-2845页

作者： LIU Shuang1,4& GONG Peng1,2,31State Key Laboratory of Remote Sensing Science, Jointly Sponsored by institute of Remote Sensing Applications of chinese academy of Sciences,and beijing Normal University, beijing 100101, China 2institute for Global Change studies & Center for Earth System Science, Tsinghua University, beijing 100084, China 3Department of Environmental Science, Policy and Management, University of California, Berkeley, CA94720, USA 4Graduate University of chinese academy of Sciences, beijing 100049, China State Key Laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate University of chinese academy of Sciences Beijing China institute for Global Change studies & Center for Earth System Science Tsinghua University Beijing China Department of Environmental Science Policy and Management University of California Berkeley USA

Surface greenness reflects the situation of vegetation *** index calculated from the Red and Near Infrared bands of remote sensing images,whose values indicate the level of photosynthetic activity,is monotonically related to surface greenness when vegetation canopy does not fully cover the background *** for desert regions,vegetation index is positively correlated with vegetation ***,vegetation index can be used to study the change in greenness of desert *** study collected MODIS Normalized Difference Vegetation Index (NDVI) data from 2000 to 2010 and analyzed their change over China in this *** results showed that an increasing trend of NDVI occurred over 66.84% (OLS fitting) or 64.27% (LAD fitting) of China,indicating that China's greenness is increasing ***,desertification of China *** showing large increase in greenness are found in Shaanxi,Shanxi,Ningxia,Henan,Shandong,Qinghai,and Gansu while regions with large decrease in greenness are found in Northeast Inner Mongolia,South Tibet,Jiangsu,and *** of Qinghai,Gansu,Xinjiang and South Tibet could probably be driven by climate *** of greenness in Northeast Inner Mongolia was related to agricultural *** of greenness in Jiangsu and Shanghai was related to rapid *** factors did not exhibit obvious correspondence to the large increase in greenness in Shaanxi,Shanxi,Ningxia and Gansu,indicating that the changes might have been caused by human *** reduction of desert areas in China could probably have been caused by human management and protection at the national scale.

关键词：中国地表覆盖归一化植被指数植被覆盖度沙漠地区 NDVI 西藏南部气候因素

THE INFLUENCE OF HUMAN BEING ON THE desertification OF ORDOS AND THE POSSIBLE COUNTERMEASURES IN THE FUTURE

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干旱区资源与环境 1993年第Z1期7卷 34-37页

作者： Leng Shuying institute of Geography, chinese academy of sciences, beijing

The Ordos Plateau is a unified geographical region demarcated by the Yellow River’s elbow section on the north and the Great Wall on the south, administratively comprisingthe whole Ih-Ju League of Inner Mongolia, part of Yulin Prefecture of Shaanxi Province,and part of Yanchi County of Ningxia. The unique sandy and denuded landscape of the pla-

关键词： Ordos Plateau Human Activity Land desertification

Simulated multi-scale watershed runoff and sediment production based on GeoWEPP model

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International Journal of Sediment Research 2009年第4期24卷 465-478页

The runoff and sediment yield data from the Qiaozidonggou, Qiaozixigou, and Lu’ergou watersheds, in the Loess Plateau of China are used to calibrate and validate the runoff and sediment yield simulated by GeoWEPP model of the WEPP Model at watershed scale. The indices of relative error, R, correlation coefficient, R 2 , and Nash-Suttcliffe efficiency coefficient En s are used to evaluate the model fit. The eco-hydrological responses in the Luoyugou and Lu’ergou watersheds are also forecast based on the WEPP Model. Meanwhile, the relation between vegetation pattern changes and sediment yield in the watershed is discussed, and the responses of runoff and sediment yield in the watersheds concerning forest growth stages are studied. The results show that the relative errors of simulated values of runoff and sediment yield are below 30%, the correlation coefficients are above 0.90, and the Nash-Suttcliffe efficiency coefficients are above 0.80. The simulation results present satisfactory performance, thus, the model could be used to simulate the runoff and sediment yield in these small watersheds. It is also observed that soil erosion tended to become severe as precipitation increased in the watershed, while soil erosion has a decreasing trend as forest cover increases and vegetation pattern is optimized. When the watershed is fully covered by forest, erosion and sediment yield are minimized. When the forest cover is about 30% and evenly distributed in the watershed, the erosion intensity is lower than if the forest cover is collectively distributed in the watershed. Erosion varies with different forest growth stages in the watershed; it is more serious at the young and near planting stage and is the smallest at the mature forest stage.

关键词： GeoWEPP model Eco-hydrological response Watershed runoff Sediment yield Model calibration Erosion modeling

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science China Earth Sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3,4 1National Marine Environmental Forecasting Center, beijing 100081, China 2First institute of Oceanography, State Oceanic Administration, Qingdao 266061, China 3State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, institute of Atmospheric Physics, chinese academy of Sciences, beijing 100029, China 4Graduate University of chinese academy of Sciences, beijing 100049, China 1. National Marine Environmental Forecasting Center Beijing 100081 China2. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China3. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

Research on TemporaI and Spatial Patterns and Dynamic Laws of Soil Water at Eco-tope between Oasis and Desert

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chinese forestry Science and Technology 2002年第2期1卷 31-37页

作者： WANG Bing CUI Xianghui BAO YonghongThe Research institute of Forest Ecology. Environment and Protection chinese academy of forestry. beijing 100091, China

Based on long term and stationary research, the temporal and spatial patterns and dynamic laws of soil water content in Minqin desert area were studied. Some results are as follows:(1)The change of soil water content in different years is not obviously in shrub sand dune of Nitraria sibirica and Tamarix ramosissima, but it was great in shifting sand dune, the maximum is 2.538%; (2)The season dynamics can be divided into three stages: accumulating, consuming and stable; (3) The vertical change of soil wa...

关键词： Minqin desertification soil water content temporal and spatial pattems dynamic laws

Study of spatial distribution of sandy desertification in North China in recent 10 years

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Science China Earth Sciences 2004年第z1期47卷 78-88页

作者： WANG Tao, WU Wei, XUE Xian, SUN Qingwei & CHEN GuangtingKey Laboratory of Desert and desertification, Cold and Arid Regions Environmental and Engineering Research institute, chinese academy of Sciences, Lanzhou 730000, China Department of Environment Engineering, Peking University, beijing 100871, China chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Key Lab Desert & Desertificat Lanzhou 730000 Peoples R China Peking Univ Dept Environm Engn Beijing 100871 Peoples R China

Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in China. Rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North China. Remote sensing monitored results in 2000 showed that the sandy desertified land area has been 38.57× 104 km2. The area of potential to slightly sandy desertified land is 13.93× 104 km2, moderately land 9.977×104 km2, severely land 7.909 ×104 km2 and very severely land 6.756×104 km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100 km2 ·a-1 in 1976-1988 to 3,600 km2 · a-1 in 1988-2000. The basic status of sandy desertification in North China is 'overall deterioration, while local rehabilitation'. Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North China can be restored under the conditions of rational land-use ways and intensity.

关键词： sandy desertified land, spatial distribution, remote sensing monitoring, last 10 years, North China.

Progress in studies of the climate of humid period and the impacts of changing precession in early-mid Holocene

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Progress in Natural Science:Materials International 2008年第12期18卷 1459-1464页

作者： Jianbin Huang~a Shaowu Wang~a Xinyu Wen~a Bao Yang~b a Department of Atmospheric Sciences,School of Physics,Peking University,beijing 100871,China b Laboratory for Desert and desertification,Cold and Arid Regions Environmental and Engineering Research institute,chinese academy of Sciences,Lanzhou 730000,China [a]Department of Atmospheric Sciences School of Physics Peking University Beijing 100871 China [b]Laboratory for Desert and desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

studies on the climate of humid period and the impacts of changing precession in the early-mid Holocene are reviewed in this paper. High-resolution proxy data indicated that the African Humid Period,strong summer monsoon from the Arabian Sea to South Asia, northward migration of ITCZ (lntertropical Convergence Zone) over the northern South America,and the humid period of China appeared in 10.5-5.5 kaBP,10.0-6.0 kaBP,10.5 5.4 kaBP,and 11.0-8.0 kaBP,*** studies proved that summer inso- lation over the Northern Hemisphere increased following the changes of precession in the early Holocene,which increased the land-sea temperature contrasts,intensified the summer monsoon circulation in the Northern Hemisphere,and finally induced a humid climate over the area under the influence of summer ***,modeling results underestimated the increase of precipitation and the degree of northward extension of monsoon rain belt compared with palaeo-environmental *** discrepancies between the modeling results and the palaeo-environmental data may be associated with the changes of North Atlantic circulation,sea ice and veg- etation ***,climate of the humid period was not stable,in which several droughts were inlaid on centennial *** this review,perspectives for further studies of the climate change of the humid period in the early-mid Holocene are also proposed.

关键词： Holocene Humid period Precession Summer monsoon