Interactive comment on “ Temperature thresholds for Arctic plankton community metabolism : an experimental assessment ” by J . M . Holding

a sufficient number of parameters associated with the plankton community to unambiguously evaluate the community response to temperature. For example, the authors don’t provide any information about nutrient concentrations. There is no mention of nutrient additions so I assume that the populations had to exist on whatever nutrients were available at the time of collection. Given a 15-day incubation period, it is very likely that nutrients in some of the treatments may have been exhausted. Is it possible that this might explain the reduction in chlorophyll in the 9 and 10 degree treatments? We don’t know because nutrient data were not presented. In addition, phytoplankton biomass was only characterized using measurements of chlorophyll and heterotrophic biomass wasn’t characterized at all.’

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