| Woody vegetation on floodplains has recognized as several problems for river management such as flood control in Japan. Willow， bamboo， and black locust trees are dominant species and expand with high reproductive abilities by their roots in river environments. River administrators therefore need to establish methods to restrain the spread of riparian forests to keep enough river flow capacity for reducing the risk of flooding. In this study， we conducted logging operations combined with different treatments such as ring-barking and uprooting on riparian forests of above three dominant species along three rivers for evaluating the effects of logging operations with treatments on the regeneration. Our results showed that the ring-barking pretreatment decreased by 60% of the number of new ramets from stumps compared to non-ring-barking pretreatment in the willow and by 30% in the black locust.The uprooting posttreatment showed the greatest decrease (93%) of new ramets from stubs， which left behind under the ground， compared to non-uprooting treatment in the bamboo， but there was no significant difference between with and without uprooting posttreatment in the black locust. By combining treatments before and after logging operations， we have possible to decrease cost for reducing the risk of flooding. |
