Effects of tidal stage and sun angles on intertidal benthic microalgal productivity

Abstract

Measurements of microalgal production were obtained from subaerially exposed cores collected from low-intertidal muddy sediments in North Inlet Estuary, South Carolina. Microalgal productivity at low tide was twice that at high tide (mean difference 52%) and was significantly correlated with diurnal and tidal periodicities. Production values ranged from 28.0-460.5 μmol O2 mg chl a-1 h-1 and maximum rates were achieved during mid-afternoon low tides. Although other physiological and abiotic factors also influence benthic microalgal productivity, much of the short-term variability in production rates may be simply attributed to migratory rhythms within estuarine sediments. -from Authors