抄録
An investigation on relationship between sea bottom environment and macrobenthic fauna was carried out at 29 points of Tokyo Inner Bay in different seasons. Concentrations of COD and total sulfide and thickness of sedimentary accumulation in all investigated areas except some coastal areas and waterways were over 30 mg·g-1, 1.0 mg·g-1 and 0.7 m respectively, which suggested that the sediment of the above area had suffered from serious organic pollution. The number of macrobenthic species decreased at the places where concentrations of COD and total sulfide and ignition loss of sediment were over 20 mg·g-1, 0.3 mg·g-1 and 8%. More than 10 species of macrobenthos were hardly observed at the places where COD concentration, ignition loss, total sulfide concentration of sediment and thickness of sedimentary accumulation were over 50 mg·g-1, 14%, 2 mg·g-1 and 1 m, respectively. No macrobenthos was observed in the offshore areas with serious organic pollution and macrobenthic fauna at the places surrounding was very poor in summer. The inner area of central waterbreak, where the sediment condition was comparatively good, could have diverse and rich macrobenthic fauna in spring, however it became an area with no or poor macrobenthos in summer due to the decrease of DO in sea bottom layer.
