Colonization and recovery of lotic epilithic communities: A metabolic approach

Abstract

Community respiration and net primary productivity measurements from precleaned and disturbed substrates of various sizes were collected to examine the colonization and recovery rates of lotic epilithic communities in situ. The assumptions and limitations of the technique for monitoring metabolic recovery are discussed. The results indicate that substrate size and heterogeneity affect the rates of metabolic recovery; metabolic recovery of the heterotrophic community component generally occurs before the autotrophic; following a physical disturbance 13–21 days are required for metabolic recovery while pre-cleaned mixed and homogenous large sized substrates require 15–21 days; a temporary summer metabolic equilibrium appears to exist in the Sheep River, the duration of which is dependent on abiotic environmental variables. Future metabolic studies should include structure and composition measurements to attain maximum information on the recovery of epilithic communities.