Satellite-Based Analysis of Evapotranspiration and Water Balance in the Grassland Ecosystems of Dryland East Asia
作者:Xia, JZ (Xia, Jiangzhou)[ 1,2 ] ; Liang, SL (Liang, Shunlin)[ 1,2,3 ] ; Chen, JQ (Chen, Jiquan)[ 4 ] ; Yuan, WP (Yuan, Wenping)[ 5 ] ; Liu, SG (Liu, Shuguang)[ 6 ] ; Li, LH (Li, Linghao)[ 7 ] ; Cai, WW (Cai, Wenwen)[ 5 ] ; Zhang, L (Zhang, Li)[ 8 ] ; Fu, Y (Fu, Yang)[ 5 ] ; Zhao, TB (Zhao, Tianbao)[ 9 ] ; Feng, JM (Feng, Jinming)[ 2,9 ] ; Ma, ZG (Ma, Zhuguo)[ 9 ] ; Ma, MG (Ma, Mingguo)[ 10 ] ; Liu, SM (Liu, Shaomin)[ 1,11 ] ; Zhou, GS (Zhou, Guangsheng)[ 12 ] ; Asanuma, J (Asanuma, Jun)[ 13 ] ; Chen, SP (Chen, Shiping)[ 7 ] ; Du, MY (Du, Mingyuan)[ 14 ] ; Davaa, G (Davaa, Gombo)[ 15 ] ; Kato, T (Kato, Tomomichi)[ 16 ] ; Liu, Q (Liu, Qiang)[ 1,2 ] ; Liu, SH (Liu, Suhong)[ 1,11 ] ; Li, SG (Li, Shenggong)[ 17 ] ; Shao, CL (Shao, Changliang)[ 7 ] ; Tang, YH (Tang, Yanhong)[ 18 ] ; Zhao, X (Zhao, Xiang)[ 1,2 ]
PLOS ONE
卷: 9  期: 5
文献号: e97295
DOI: 10.1371/journal.pone.0097295
出版年: MAY 20 2014

摘要
The regression tree method is used to upscale evapotranspiration (ET) measurements at eddy-covariance (EC) towers to the grassland ecosystems over the Dryland East Asia (DEA). The regression tree model was driven by satellite and meteorology datasets, and explained 82% and 76% of the variations of ET observations in the calibration and validation datasets, respectively. The annual ET estimates ranged from 222.6 to 269.1 mm yr(-1) over the DEA region with an average of 245.8 mm yr(-1) from 1982 through 2009. Ecosystem ET showed decreased trends over 61% of the DEA region during this period, especially in most regions of Mongolia and eastern Inner Mongolia due to decreased precipitation. The increased ET occurred primarily in the western and southern DEA region. Over the entire study area, water balance (the difference between precipitation and ecosystem ET) decreased substantially during the summer and growing season. Precipitation reduction was an important cause for the severe water deficits. The drying trend occurring in the grassland ecosystems of the DEA region can exert profound impacts on a variety of terrestrial ecosystem processes and functions.

通讯作者地址: Liang, SL (通讯作者)
Chinese Acad Sci, State Key Lab Remote Sensing Sci, Jointly Sponsored Beijing Normal Univ & Inst Remo, Beijing, Peoples R China.
地址:
[ 1 ] Chinese Acad Sci, State Key Lab Remote Sensing Sci, Jointly Sponsored Beijing Normal Univ & Inst Remo, Beijing, Peoples R China
[ 2 ] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China
[ 3 ] Univ Maryland, Dept Geog Sci, College Pk, MD 20742 USA
[ 4 ] Nanjing Univ Informat Sci & Technol, Int Ctr Ecol Meteorol & Environm IceMe, Sch Appl Meteorol, Nanjing, Jiangsu, Peoples R China
[ 5 ] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China
[ 6 ] Cent South Univ Forestry & Technol, State Engn Lab Southern Forestry Appl Ecol & Tech, Changsha, Hunan, Peoples R China
[ 7 ] Chinese Acad Sci, State Key Lab Vegetat & Environm Change, Inst Bot, Beijing, Peoples R China
[ 8 ] Chinese Acad Sci, Key Lab Digital Earth Sci, Inst Remote Sensing & Digital Earth, Beijing, Peoples R China
[ 9 ] Chinese Acad Sci, Inst Atmospher Phys, Key Lab Reg Climate Environm Res Temperate East A, Beijing, Peoples R China
[ 10 ] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou, Gansu, Peoples R China
[ 11 ] Beijing Normal Univ, Sch Geog, Beijing 100875, Peoples R China
[ 12 ] Chinese Acad Meteorol Sci, Beijing, Peoples R China
[ 13 ] Univ Tsukuba, Ctr Res Isotopes & Environm Dynam, Tsukuba, Ibaraki, Japan
[ 14 ] Natl Inst Agroenvironm Sci, Dept Agrometeorol, Tsukuba, Ibaraki 305, Japan
[ 15 ] Inst Meteorol & Hydrol, Juulchin, Ulaanbaatar, Mongol Peo Rep
[ 16 ] Hokkaido Univ, Res Fac Agr, Sapporo, Hokkaido, Japan
[ 17 ] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China
[ 18 ] Natl Inst Environm Studies, Ctr Environm Biol & Ecosyst Studies, Tsukuba, Ibaraki, Japan