A Study on Relationships Between Space Units and Biotic Communities

The authors tried to clarify the relationships between space units and biotic communities of man made off-stream ponds by a case study. An experimental pond excavated in the reed wetland located in Mitinoku Lakewood National Government Park, Miyagi Prefecture, north-east part of Japan. The construction work completed in March of 1996. Both aboitic and biotic condition data were collected from July 1996 toFebruary 1997. Consequently, four different types of space units were identified as followings.(1) type 1; shallow, high speed stream, gravel bottom(2) type 2; shallow, low speed strem, sand botto(3) type 3; shallow, extremly low speed stream, mud bottom(4) type 4; deep, extreamly low speed stream, mud bottom.These four types of space units were identified mainly by stream velocity and depth of water. And each types had their own species composition of benthic fauna classified by life forms. Identification andmapping of physio-bio (phyisiological and biological) space units are useful for management or recreation of ponds and streams for benthic fauna.