Posted by Michelle:
Angie and I traveled to Egersund to sample lakes in the high nitrogen deposition region of Norway. We visited a total of 7 lakes, collecting zooplankton and trace greenhouse gases from all lakes, but sediment (mud) from only 6 lakes. One lake was unusually clear and the dredge I use to collect mud was no match for macrophytes (aquatic plants) at 10m. Much to our surprise, we found no Daphnia in the first 5 lakes. Rather, these lakes were full of copepods and globs and globs of Holopedia. Fortunately there were Daphnia in the last 2 lakes we sampled – Saglandsvatnet and Revsvatnet. 5 of the 7 lakes we visited were also sampled by the Elser lab in 2007, so it was nice to revisit areas I had already seen.
Angie survived her first round of limnological field work and has developed quite a talent with the zooplankton net. I should also note that we sampled 5 lakes on 13 June, our first day in the field. Note to self: never sample 5 lakes in one day!
We are back in Oslo and will start the laboratory portion of our work. Angie will analyze the zooplankton for concentrations alkaline phosphatase, an indicator of phosphorus limitation. I will conduct nutrient enrichment bioassays with the mud. Stay tuned for more details of our lab work.