Coarse particulate organic matter exports and characteristics during flood events

Abstract

Quantity and quality of exported coarse particulate organic matter was investigated in Nakatsugawa River, the second order stream in Saitama Prefecture during 5 flood events occurred between 2005 and 2008. Average drift density was ranged from 0.21 g m-3, 1.52 g m-3 and 2.84 g m-3 (dry weight) for winter, summer and autumn flood, respectively. Drift density was weakly correlated with discharge. However, lignin contents in leaf was higher in flood magnitude, and correlated with discharge. Based on the quality, exported CPOM was significantly different among the flood events as classified by the discriminant analysis. Flood timing and magnitude are highly affected the quantity and the quality of exported CPOM.