JOURNAL OF NATURAL RESOURCES ›› 2010, Vol. 25 ›› Issue (9): 1596-1606.doi: 10.11849/zrzyxb.2010.09.019

• Resources Research Methods • Previous Articles     Next Articles

Study on Evapotranspiration in East Asia Using the BEPS Ecological Model

ZHANG Fang-min1, JU Wei-min2, CHEN Jing-ming3, WANG Shao-qiang4, YU Gui-rui4, LI Ying-nian5, HAN Shi-jie6, J.ASANUMA7   

  1. 1. Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information Science & Technology, Nanjing 210044, China;
    2. International Institute for Earth System Science, Nanjing University, Nanjing 21009;
    3. Department of Geography and Program in Planning, University of Toronto, Toronto, M5S 3G3, Canada;
    4. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    5. Northwest Institute of Plateau Biology, CAS, Xining 810008, China;
    6. Institute of Applied Ecology, CAS, Shenyang 110016, China;
    7. Terrestrial Environment Research Center, University of Tsukuba, Tsukuba, Japan
  • Received:2014-04-04 Revised:2010-07-07 Online:2010-09-20 Published:2010-09-20

Abstract: East Asia is one of the most complicated and disputed areas of carbon and water cycles due to the integrated effect of variable climate and intense human disturbances. Evapotranspiration (ET) is an important component of the carbon-water cycle; however, regional studies of ET in East Asia are still few. This study is to analyze the spatio-temporal distributions of ET in East Asia during 1982 to 2006 using the process-based ecological model BEPS, which was driven by meteorological, soil and remote sensing data at an 8-km resolution. Prior to the regional simulation, BEPS was validated using measured ET in six typical forest ecosystems. BEPS can explain 81.23% of the annual ET and 86.4% of the 10-day ET variations, respectively, indicating that BEPS can accurately simulate ET in East Asia. Simulated annual ET in East Asia shows a gradually decreasing pattern from the southeast and northeast regions to the northwest and southwest desert areas, with the smallest values in the northwestern desert region of China. It also shows that the ratio of ET and precipitation was increasing from the southeast and northeast regions with an average of 0.4 to the northwest and southwest desert region with the values greater than 1.0. The annual total ET in East Asia averaged from 1982 to 2006 was 12045 ×109 m3/a, and China, Pan Southeast Asia and India accounted for 62.4% of the annual total ET. Mean ET per unit area of the study area was 401 mm/a, with the largest values in Pan Southeast Asia (1100 mm/a), and the smallest values in Mongolia (134 mm/a). Relative to the different land cover types, the maximum of the total and mean ET values were the evergreen broad-leaved forests, while the minimum values were both in urban and built-up areas. The whole East Asia region showed a significant increasing trend in ET. Grasslands, savannas, bare land and urban land marked a noticeable increasing trend of ET, yet other vegetation types did not change significantly.

Key words: evapotranspiration, process-based ecological model, remote sensing, terrestrial ecosystems, East Asia

CLC Number: 

  • P467