Mass Balance of Biofilm in the Hikiji River

Abstract

This study aimed to estimate the role of biofilm in riverine mass balance by measuring the content of total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP). The river biofilm samples were collected from the alumina boards we installed in the riverbed in the Hikiji River. The observed growth rates of the biofilm were 0.012 ± 0.005 mgC cm^-2 day^-1, 0.0048 ± 0.0018 mgN cm^-2 day^-1, and 0.0007 ± 0.0003 mgP cm^-2 day^-1. The C:N:P mole ratio was 48:15:1 (n = 23, C/P = 48 ± 15, N/P = 15 ± 3). The respiration amount of the producers and the consumers in the biofilm was reducing 55~60 % of the TOC in the biofilm.