Submerged aquatic bryophyte flora in the upper and middle reaches of the Yahagi River, central Japan

Abstract

We investigated the species composition and distribution of aquatic bryophytes in the riffles of upper and middle reaches of the Yahagi River, Japan, by longitudinal and cross-sectional observation. Ten species of Bryopsida (mosses) and one species of Hepaticopsida (liverworts) were recorded in this study. A rich flora of bryophytes was observed at the water edges and in the splash zones of large boulders, comparable to previous studies, whereas Ectropothecium obtusulum and Rhynchostegium riparioides were found to dominate in channels where water flows throughout the year. They were commonly found on the submerged riverbed of the Yahagi River, and these two species were more abundant in many study stations below dams.