Biocide treatment for mosquito control increases CH4 emissions in floodplain pond mesocosms

Shallow lentic freshwater aquatic systems are globally important emitters of methane (CH 4 ), a highly potent greenhouse gas. Previous laboratory studies indicated that bioturbation by chironomids can reduce CH production and increase oxidation enhancing oxygen transport into sediment. Thus, reduction in chironomid density application biocides for mosquito control, such as Bacillus thuringinesis var. israelensis (Bti), have the potential to affect emissions. We evaluated effect 41% larvae abundance due Bti applications on dynamics aquatic-terrestrial transition zones 12 floodplain pond mesocosms (FPMs) (half treated, half control). short-term (2 months) seasonal effects measuring emissions, dissolved concentrations, rates spring, summer, autumn, winter. On average, emissions from zone treated FPMs were 137 % higher than those control FPMs. The lack differences mean between suggests associated decreased sediment promoted Our findings point biogeochemistry through alterations abundance, highlight underestimated role invertebrates biogeochemical cycling these ecosystems.