Abstract
An aquatic plant is classified into an emergent plant, a floating-leaved plant, and a submerged plant according to a life form. The submerged plant occupied most aquatic plants in the plain lakes.However, it declines nationally from the middle of the 1950s, and has disappeared in many lakes now. This research aimed to the reconstruction of the distribution area before a decline of the submerged plant which becomes important in natural restoration of a lake, using the U.S. aerial photograph taken in 1947.