S-W denotes the WBIF from the soil eDNA sample (riparian zone) to the water eDNA sample (river). SL1, SL2, SL3, SL4, SL4b, SL5m, SL5, SL6 and SL6b denote the sampling transections. S-W_SL1 denotes the WBIF from the riparian zone to the river at SL1. 201904, 201906, and 201909 indicate the groups that were sampled in April, June and September 2019, respectively. Transport capacity indicates the proportion of soil microbes that were transported into the river. Environmental filtration indicates that the proportion of soil microbes that could not be kept in rivers. Transportation effectiveness indicates the proportion of soil microbes that could be detected in rivers.