Seasonal variability in microbial methanol utilisation in coastal waters of the western English Channel

Methanol is ubiquitous in seawater and is the most abundant oxygenated volatile organic compound (OVOC) in the atmosphere, where it influences oxidising capacity and ozone formation. Marine methylotrophic bacteria utilise methanol in seawater as an energy and/or growth substrate. This work represents the first fully resolved seasonal study of marine microbial methanol uptake dynamics. Rates of microbial methanol dissimilation in coastal surface waters of the UK varied between 0.7 and 11.2 nmol l−1 h−1 and reached a maximum in February. Rates of microbial methanol assimilation varied between 0.04 and 2.64 × 10−2 nmol l−1 h−1 and reached a maximum in August. Temporal variability in microbial methanol uptake rates shows that methanol assimilation and dissimilation display opposing seasonal cycles, although overall,