Landscape change of riparian forest and its stand structure in the eastcoast plain of Lake Biwa

Riparian forest along river in the plain area, especyally in urban area or its fringe, may contain various function for enviromental conservation. It seems, however, that they are reducing by urban deveropment. The survey and investigation were made in order to obtain the landscape change of riparian forest and its vegetative structure, in case of Shiga prefecture. Results are as follows:(1) Riparian forest has been reducing for 100 years, especially in the urbanized area.(2) In the lower area of the river, bamboo forest grows and into the upper area, woody forest can occur.(3) Bamboo forest is changing into mixed forest with broad-leaved trees.(4) Pine forest is also changing into broad-leaved tree forest.(5) The mixed forest has a diverse structure, in which at the forest crown deciduous tree is dominant, and at the lower level evergreen grows. Such a mixed forest is expected to have a various function for environmental conservation, for instance, as a recreation forest.