Abstract
We investigated micro geomorphology, light environments and species composition of riparian vegetation along a montane stream in northern Japan. Vegetation structure was compared between sites around a dam and sites of more up stream.
In sites around the dam, micro geomorphology was relatively homogeneous and the light levels were higher than in sites of more up stream.
In sites around the dam, vegetation paches larger than in sites of more up stream. Species diversity in vegetation paches were not variance, however, species diversity of whole study sites were relatively homogeneous in sites around the dam than sites of more up stream.
In sites around the dam, Pioneer trees such as Alnus and Salix invaded.
In sites around the dam, earth and sand accumulated and river slopes became gentle and stable. These created relatively homogeneous micro geomorphology and large vegetation paches and promoting tree invation.
These changes of environments reflected relatively homogeneous species composition.
