| Abstract Even when anthropogenically altered, riverfloodplains continue to contribute to biodiversity. Thisstudy examined the distribution of freshwater mussels inrelation to environmental factors in waterbodies in the terrestrialized floodplain of a lowland river. Mussels were captured, and environmental measurements were taken in November of 2013 and 2014 in quadrats established in three floodplain waterbodies (FWBs), which were solated from the main river channel. Among the three FWBs, mussel abundance was highest in a shallow FWB (depth range 18-45 cm) that had intermediate conditions of mud depth and fine sediment rate. Mussel abundance showed a hump-shaped relationship with water depth (the peak 45-50 cm) and mud depth (the peak 8-12 cm). Mussel abundance was also negatively related to the abundance of benthic litter. Litter abundance was ositively related to branch abundance and the presence of tree cover, and negatively related to the distance to tree cover, indicating that benthic litter was derived from riparian trees. Our results indicate that relatively shallow (B 50 cm) FWBs with moderately accumulated mud, which are not scoured even during flooding, appear to be suitable habitats for mussels. Moreover, it is possible that riparian trees negatively impact mussel distribution in FWBs. Possible short-term measures for improving mussel habitat in FWBs may include the elimination of riparian trees and benthic litter. |
