The lecturer will provide various topics about nature, and we will exchange opinions with the participants. It will be held once a month from July to November.

*Image is for illustrative purposes only

■Lecturer: Mr. Kazuo Yabe (Professor Emeritus, Sapporo City University; President, Japanese Society of Wetland Science)

■Title: "Recent Changes in the Plant Communities of the Bibi River and Lake Utonai – A Report on the Results of the Bibi River Nature Restoration Project –"

■Lecture Content
In the Bibi River and Lake Utonai basin, significant changes have occurred in aquatic plant communities, river channels, and wetlands due to water level fluctuations and increased nutrient loads. At Lake Utonai, with the re-rise in water level after a drop, Sugimamo, which prefers shallow areas, has decreased, and the communities have changed to those dominated by Hozakinofusamo and Sekishomo. In the Bibi River, increased nitrogen and phosphorus concentrations led to an overgrowth of Kusayoshi, which blocked the river channel, but submerged plants such as Baikamo have recovered due to improved flow velocity from channel width adjustments.

Furthermore, on the northwestern shore of Lake Utonai, rewetting of the wetland is progressing due to water level management, and the community structure is showing a trend of recovery. These results indicate that appropriate management of water levels and flow velocity is effective for ecosystem regeneration.