EXPANSION MECHANISM OF <i>SALICACEOUS</i> SPECIES FOREST AND ITS MANAGEMENT TECHNIQUE IN THE ASAHI RIVER

The expansion mechanism of Salicaceous species forest in the middle reaches of the Asahi River was investigated by ecological field surveys and experiments. The results of the study show that Salicaceous species take root on a damp riverbed, wither if the riverbed immediately dries. A bank protection effect by Salicaceous species contributes to the stability and the expansion of the bar, and the direction of flood flow and the existence of a dammed up area influence the habitat of Salicaceous species. The control technology and the spatial layout of Salicaceous species forest were proposed based on the obtained inclusive scenario for the expansion of Salicaceous species