Statistical analysis of woody debris volume to specify mechanism of recruitment in dam reservoirs in Japan

Abstract

 In order to identify the factors related to runoff of woody debris, we analyzed the relationship between woody debris volume and some parameters which are basin area and inflow discharge by using the data of woody debris volume deposited annually into 1103 dam reservoir across Japan. After quality check of these data, we applied single regression analysis. The results showed that woody debris volume increased logarithmically with inflow discharge. To find further relationship between woody debris volume and other parameters, we applied multiple regression analysis. It showed that woody debris volume is related to forest area, inflow discharge and 5 year daily rainfall.