Author(s): Kazuhiro Azami; Takashi Asaeda; Kazhumi Tanida

Linked Author(s): Takashi Asaeda

Keywords: No Keywords

Abstract: In limited-water-level reservoirs, areas along the reservoir shoreline are often exposed within the drawdown zone when water levels are reduced from normal to limited levels during the flood season. To prevent erosion and to conserve the landscape, test plantings and landscaping along the shoreline have been implemented at some dam reservoirs. The establishment of vegetation within the drawdown zone contributes to the conservation of both the landscape and wildlife habitat. The distribution, habitat, and seed dispersal period of willows such as Salix subfragilis were investigated at the Miharu Dam reservoir in northeastern Japan. Eight willows species were found around the Miharu Dam, but S. subfragilis dominated within the drawdown zone. Field survey results beginning in 1995 indicated that the size of the S. subfragilis community increased after initial impoundment. Although many of the other Salix species disperse seeds prior to the drawdown period, S. subfragilis disperses during and after drawdown in the spring; thus, when water levels are lower than normal, its seeds are supplied to the newly exposed zones that provide suitable habitat for Salix seedling establishment. Our results suggest that S. subfragilis dominated because of water-resistant properties and the timing of the seed dispersal period.

DOI:

Year: 2018