Table of Contents Author Guidelines Submit a Manuscript
Advances in Meteorology
Volume 2015 (2015), Article ID 148913, 7 pages
http://dx.doi.org/10.1155/2015/148913
Research Article

Influence of the Three Gorges Project on the Water Resource Components of Poyang Lake Watershed: Observations from TRMM and GRACE

1Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China
2Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, China
3State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430079, China

Received 11 December 2014; Revised 24 March 2015; Accepted 8 April 2015

Academic Editor: Charles Jones

Copyright © 2015 Xiaobin Cai et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The Three Gorges Project (TGP) has received many criticisms about its potential effects on the changes in the downstream ecosystems. Poyang Lake is the largest body of water downstream of the TGP, and it is not immune to these changes. TRMM and GRACE data were introduced in this study to estimate river-lake water exchange, from which the hydrological responses of Poyang Lake could be identified. A significant decreasing trend of the runoff coefficient has been observed since 2003, resulting in 6.02 km3 more water discharge from the lake into the Yangtze River than under normal conditions. No significant interannual changes occurred in the water level or local precipitation, and GRACE observations revealed that groundwater discharge appeared to be the most likely compensation for the water loss. A novel approach, namely, the groundwater abnormality index (GAI), was developed to depict the water exchange using GRACE and surface water observations. Lower than normal GAIs were found between 2003 and 2005, reaching a minimum of −29.26 in October 2003, corresponding to ten times of the mean GAI during 2006–2012, clearly indicating a significant water exchange in Poyang Lake Basin from groundwater to surface water after the TGP impoundment.