SYNERGY OF LOW AND MEDIUM RESOLUTION ENVISAT ASAR AND OPTICAL DATA FOR LAKE WATERSHED MONITORING: CASE STUDY OF POYANG LAKE (JIANGXI, P. R. CHINA)

摘要

Poyang Lake, one of the most regularly flooded areas in China, can be considered as a key natural flood control and reduction element within the Changjiang middle basin. Within the Flood DRAGON Project, part of the MOST-ESA DRAGON Programme, Poyang Lake's water extent was monitored based on 64 ENVISAT low and medium resolution ASAR and MERIS Full Resolution data, over a two and half year period. It's the first time that such an amount of ENVISAT data was exploited in monitoring inland lake water extent variations. This original integration approach permitted: lake-surface variation analysis, yearly submersion-time estimation, and the recognition of three hydrological sub-systems. The results highlight the great potential of ENVISAT and more largely of Earth Observation Medium Resolution data in monitoring and managing large inland water bodies. This approach can be applied worldwide in a global climate change context.