Kalix river

We collected Kalix water from a bridge close to Svartbyn, Sweden (66°15'26.97"N; 22°49'28.38"E) in June 2011. In the period from mid-May to late June rivers in the subarctic region reach a peak flow due to snow melting. The Kalix River drains a catchment (23846 km2) that is rich in peatland (17 – 20%) and coniferous forest (55 – 65%) and is sparsely populated (less than 1% farmland) (Ingri et al., 2005). The water from the Kalix river was collected using an in-situ-pump module with 10 µm filter and one 0.2 µm filter and transported in 1000 l polyethylene tanks to the IOWdistributed into 25 l polyethylene carboys which were then stored frozen at -20°C until use.