Data från: "Effekten av ökad sedimentbelastning och ljusinsläpp på vattendrags primärproduktion, respiration och algsammansättning"

We estimated biofilm biomass as chl α (µg cm-2) in each channel. For all chl α estimates, we used a BenthoTorch, an in-situ, hand-held fluorometric instrument (bbe Moldaenke, Germany). The BenthoTorch estimates chl α and distinguishes between diatoms, green algae and cyanobacteria. Estimates of total chl α from a BenthoTorch compare well with conventional spectrophotometric methods when biofilms are relatively thin, as in our situation. However when quantifying community composition, the BenthoTorch have been shown to overestimate the abundance of diatoms, yet the instrument performs well in factory calibrations against standards. Still, we only used the community composition results to note presence or absence of green algae in the channels. All statistical analyses used the sum of diatoms, green algae and cyanobacteria (i.e. total chl α).

Each channel was equipped with a miniDOT (Precision Measurement Engineering Inc., USA) to record dissolved oxygen. Metabolism was estimated using the single-station diel oxygen method approach where gross primary production (GPP) and Ecosystem Respiration (ER) was estimated using Bayesian inverse modelling.

De experimentella kanalerna finns vid Svartbergets forskningsstation utanför Vindeln i Västerbotten. De undersökta bäckarna finns utanför Nordmaling, Rödånäs, Gräsmyr, Bjurholm och Vindeln.