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Estimating surface evapotranspiration using combined MODIS and CBERS-02.data

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science china(Technological sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2. LIU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2. ZHENG Hongsheng4.& CHEN Jiayi4.1. State Key Laboratory of Remote Sensing science, Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 100101, {2. 2. Research Center for Remote Sensing and GIS, Department of geography, Beijing Normal university, Beijing 100875, {2. 3. Graduate university of Chinese Academy of sciences, Beijing 100039, {2. 4. Department of Atmospheric Physics, Peking university, Beijing 100871, {2. 1. State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02.data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2.04. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Study on NDVI-T_s space by combining LAI and evapotranspiration

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science china Earth sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4. YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. Research Center for Remote Sensing and GIS, School of {4., Beijing Normal university, Beijing 100875, {2. 2. State Key Laboratory of Remote Sensing science, Beijing 100875, {2. 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, Beijing 100875, {2. 4. Department of Information Management, College of Information and Electronic Engineering, {2. Agricultural university, Beijing 100083, {2. 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing science Beijing 100875 China 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3 ,HUANG Zhiqin 2. 3, 4.1. The Faculty of geography and Resources science, Sichuan Normal {2., Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 61004., Sichuan, china 3. Graduate {2. of the Chinese Academy of sciences, Beijing 10004., china 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 61004., Sichuan, china The Faculty of geography Resources science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of sciences 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern china

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science china Earth sciences 2006年第8期49卷 881-888页

作者： WANG Jian1 & LI Shuo2.1. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of sciences, Lanzhou 730000, china 2. College of {2., Nanjing Normal university, Nanjing 2.0097, china 1. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. College of geography Nanjing Normal University Nanjing 210097 China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern china. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2.01. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4. were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4. warming scenario.

关键词： climatic changes, snowmelt runoff, SRM model, upper Heihe Watershed, simulating.

Monitoring of rice crop using ENVISAT ASAR data

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science china Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. SUN Guoqing1,3 & PANG Yong4.1. State Key Laboratory of Remote Sensing science, Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 100101, {2. 2. Graduate university of Chinese Academy of sciences, Beijing 100039, {2. 3. Department of geography, university of Maryland, College Park, MD 2.74.0} USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, Chinese Academy of For-estry, Beijing 100091, {2. 1. State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate university of Chinese Academy of sciences Beijing 100039 China 3. Department of geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

Climate instability in the Yili region, Xinjiang during the last glaciation

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Chinese science Bulletin 2000年第17期45卷 1604-1609页

作者： YE Wei, DONG Guangrong, YUAN Yujiang & MA Yingjie1. Xinjiang Institute of Ecology and geography, Chinese Academy of sciences, Urumqi 830011, {2. 2. Department of geography, Zhejiang Normal university, Jinhua 32.004. {2. 3. Institute of Desert Research, Chinese Academy of sciences, Lanzhou 730000, {2. 4. Xinjiang Institute of Meteorological Research, Urumqi 830002. {2. Xinjiang Institute of Ecology and geography Chinese Academy of Sciences Urumqi China Department of geography Zhejiang Normal University Jinhua China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Xinjiang Institute of Meteorological Research Urumqi China

The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the Xinjiang Uygur Autonomous Region. Through the study of the loess section with a thickness of 2..5 m, much useful information about climatic change in this region during the last glaciation was gotten. Grain size analysis of loess samples in the section showed that the climatic change in the Yili region was of instability during the last glaciation and similar to those of the North Atlantic Ocean and Greenland. In correspondence with the Heinrich events, the percentage of the size fraction of loess with grain size less than 10 μm decreased in cold stadials in the Yili region. This result suggests that the westerly wind be strengthened during the cold periods. Compared with the stadials, the content of the loess with grain size less than 10 μm was increased in interstadials, which indicated that the strength of the westerly wind was weakened. It is obvious that the climate was instable

关键词： Yili region last glaciation climate instability.

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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science china Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3,4. ZHANG Hucai2. WANG Weiguo3 & AN Chenbang3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 2.0008, {4. 2. Nanjng Institute of {2. and Limnology, Chinese Academy of sciences, Nanjing 2.0008, {4. 3. Environment and Resources College, Lanzhou university, Lanzhou 730000, {4. 4. Beijing Normal university, Beijing 100875, {4. 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng Institute of geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal university Beijing 100875 China

With the support of 18 AMS-14. data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 4..2.to 11 ka B.P. in the Jingning area. Over the period of 4.―2. ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2. ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Study Progress and Trends of Strategic Environmental Assessment in china

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Chinese Journal of Population,Resources and Environment 2009年第2期7卷 76-82页

作者： Cai Chunmiao1,2. 3, Shang Jincheng4.1. Northeast Institute of geography and Agroecology, Chinese Academy of sciences, Changchun Jilin 130012. {2. 2. Department of geography, Harbin university, Harbin Heilongjiang 150086, {2. 3. Graduate School of Chinese Academy of sciences, Beijing 100039, {2. 4. College of Urban and Environmental science, Northeast Normal university, Changchun Jilin 13002., {2. Northeast Institute of geography and Agroecology Chinese Academy of Sciences Changchun Jilin 130012 China Department of geography Harbin University Harbin Heilongjiang 150086 China Graduate School of chinese Academy of sciences Beijing 100039 China College of Urban and Environmental science Northeast Normal University Changchun Jilin 130024 China

Strategic environmental assessment (SEA) in china has developed rapidly since it was introduced into china in the 1990s. Chinese government promulgated the Environmental Impact Assessment Law of china (hereinafter referred to as the EIA Law) in 2.02. In this law, it is stipulated clearly that regional and sector plans should be assessed. Through investigating materials and analyzing literatures, this article analyses the practical and academic study achievements of SEA in china that have been achieved since the EIA Law was implemented, probes into the current situation of the main level of SEA in china-plan EIA, then summarizes the development characteristics, and eventually, puts forward the development trends of SEA in china. The research conclusions can offer the foundations for comprehending systematically the progress of SEA in china.

关键词： strategic environmental assessment plan environmental impact assessment china study progress characteristics development trends

Sediment change under climate changes and human activities in the Yuanjiang-Red River Basin

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science Bulletin 2007年第S2期 164-171页

作者： HE DaMing~(1+) REN Jing~(1,2. FU KaiDao~1 LI YunGang~1 1 Asia International Rivers Center of yunnan university,{2. 650091,{4. 2.College of tourism and geography science,yunnan Normal university,kunming 650092.china

Both the climate change and human activities are the major Influence factors to the sediment change In mountainous *** on the over 4. years' record,suspended sediment loads（SSL）change at the Manheo gauging station in the lower reaches of Yuanjiang River（upper Red River）.In this paper,the variation of the sediment and its drivers were analyzed through different methods such as synchronous data comparison,traditional correlation,linear regression,and Granger *** results show that （1）the general trend of the annual average sediment concentration（SSC）and SSL at Manheo station is increasing from the 1960s to the 1990s,and there is a quick change period after 1984.（2.the SSL and SSC at Manhao station,during different periods of the 1960s,1970s,1980s and 1990s,are 1.87,2.4., 3.12.3.63 kg/m3,and 2..7×10～6,4..3×10～6,4..1×10～6,60.3×10～6 t/a,respectively;（3）the correlation analysis end the Granger causality test proved that the climate changes in the catchment were the main driving factors to the sediment variation in the period of 1960s and 1990s,but the influence by the mountain- ous human actions on the sediment change is stronger than that by the local climate changes in the 1970s and 1980s;（4.the correlation between the sediment changes and the forest coverage change is negative,which further proves that the sediment changes are strongly affected by the human activities in the basin.

关键词： sediment change Granger causality test Yuanjiang River the Longitudinal Range-Gorge Region