River_water_chemistry

\"Measurements started in 1997 and are still on going. From 1997-2011 water samples were taken everyday at 8 am and 8 pm. From 2012-present water samples are taken three times a week at 8 am and at 8 pm. Water temperature and conductivity is measured in situ, using a YSI 30 conductivity meter. Water samples from 8 am are analyzed for pH and alkalinity in the laborratory facilities at the Zackenberg station. Cooled water samples (from 8 am) are transported to Denmark and analyzed in the laboratory at the Department of Geosciences and Natural Resource Management, University of Copenhagen, for the folowing anions and cations: Chloride, Sulfate, Sodium, Magnesium, Potassium, Calcium, Iron and Aluminum. The detection limit for all these ions is 0.1 ppm. Concentrations below this threshold have been set to 0.000. Furthermore a 20 ml subsample is taken once a week from the 8 am water sample. This sample is kept frozen and brought to the Department of Biology, University of Copenhagen, where it is analyzed for dissolved organic carbon, ammonium nitrogen, nitrate nitrogen and dissolved total nitrogen.

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