The results of geological environment remote sensing investigation and monitoring in the 1970’s, 2000 and 2007

show that new-tectonic activities do exist in Dongting Lake area, the rift basin is still in the tectonic subsidence phase,

and the changes of the geological environment in Dongting Lake area before and after the storage of water in the Three

Gorges Reservoir are obvious. All this indicates the evolution regularity of erosion and deposition in the Dongting Lake,

that is, the East Dongting Lake will continue to become smaller, but the speed will slow down；the South Dongting Lake will

experience deepened scouring, but the area will not become smaller; and the Muping Lake will remain in the original scour

state and continue to suffer silting up, but the speed will slow down. The environmental problem in the Dongting Lake will

become the problem of lower water level and decreased ground water level in dry season instead of the floods and siltation.