Implovement of habitat for fish
Implovement of habitat for fish
 Kayanuma The old channel restoration work in Kayanuma also aims to improve fish habitat. Shifting from a straight channel to the previous meandering one was expected to restore fish habitat by diversifying channel conditions. Monitoring Results
Restoration work was carried out in 2010 at the downstream end of a reach that had previously been straightened. A survey of fish habitat showed that the straightened channel is wide and shallow, whereas the restored channel is narrow and deep, similar to a natural channel. 
Water depth and flow velocity at each site were compared in detail. SAt KP33.5 in the straightened channel, shallow areas with depths less than 0.6 m accounted for 66%. This site contains many low-velocity areas, with regions where velocity is less than 0.5 m/s accounting for around 30%. While these shallow and slow-flowing areas provide suitable habitat for small fish, they are less suitable for larger fish. At KP32.0 in the restored channel, a wide range of water depths was observed, and flow velocities mainly ranged from 0.7 to 1.0 m/s. The distributions of both water depth and flow velocity in the restored channel have become similar to those in the natural channel.  
The material composition in the restored channel has become similar to that in the natural channel, indicating that the channel environment in the restored reach is now comparable to that in the natural reach. 
 Kushiro Wetland Restoration ProjectKushiro WetlandWetland Restoration Restoration Site 1 : Kayanuma, Old Channel Restoration 1 Restoration Site 2 : Numaoro, Old Channel Restoration 2 Restoration Site 3 : Kuchoro, Sediment Retention Basin Restoration Site 4 : Hororo, Reconversion of Farmland into Wetlands Kushiro Wetland Nature Restoration Council Project Goals Sediment reduction flowing into the wetland Implovement of habitat for fish Restoring Wetland Vegetation History 1 : Wetland Development History 2 : Shift Toward Wetland Conservation and Restoration Peatland |