Copepods and the methane balance Published 23.10.2011
Copepods might be the organism that could provide climate researchers with a possible explanation as to why the balance sheets on methane and nitrate in the oceans do not add up. At the Greenland Climate Research Center researchers from around the world meet in a creative and inspiring environment to find the answers to the hot topic of climate change.
Inside the bowel of the Calanus
”At last! I´ve got it! Actually, this is not at all easy…….” assistant Anni Glud is smiling with relief. She finally succeeded in attaching a copepod, more specifically a species of the family Calanus Finmarchius, to a small piece of orange moddeling wax and run a minute electrode into its bowel to measure the oxygen content. Something is happening in there. The electrode now starts a needle swinging back and forth on the measurement paper, drawing a picture of the processes in the intestines of Calanus.
Everything is smaller than small and a little shake of the hand will ruin the test. However, its importance is paramount. These tiny crustaceans, the copepods, are one of the most widespread organisms in the oceans of this planet functioning as feeding stock for the entire marine food web. That is why this little fellow is now the focus point of biologists and climate researchers. When temperatures rise, the living conditions of calanus will change in many ways and it will affect all other animals in the food chains of the marine environment.
But why test the processes in the intestines of calanus?
”In general, this is a test of the impact on the conditions of production in an Arctic marine environment when climate change has impacted and the rising temperatures change the sea-ice” explains professor Ronnie Glud from the Greenland Climate Research Center and the South-Danish University Center. Ronnie Glud is a micro biologist and conducts research in the chemistry of the sea-bed and the importance of the sea-ice considering the gas flux between the atmosphere and the oceans.
”One of the reasons for undertaking this research is that our measurements from time to time shows too large an amount of methane in the sea-water for our present models to explain. Methane is one of the so called ”greenhouse gases” that traps the warmth from the sun in the atmosphere. Methane is actually similar to a fart, so it seemed quite logical for us to try to find out whether or not that gas can be produced inside this small animal. Its intestines represent quite a lot of space in the oceans as it is the most common and widespread organism in the marine environment.”
Gasflux in focus
”We had this idea, that the intestines of the copepods might function as small reactors, which produce methane while they in exchange remove nitrate from the sea water. (Nitrate is a fertiliser that bears major impact on the production of algae.) This process can only take places in an environment free of oxygene. So, if we do not find oxygene inside the intestines of calanus, it means that there actually are large oxygene free areas in the uppermost oxidized parts of the oceans, where this kind of production could take place ” continues professor Torkel Gissel Nielsen, DTU Aqua, who specialises in copepods and Arctic plancton dynamics.
Inspiring cross-disciplinary cooperation
The combination of these two areas of research represents the whole point of the creation of the Greenland Climate Research Center. Both of the professors, Gissel and Glud, have their own projects financed by the center. Now they exploit the synergy in this joint project, which is exactly why there are so many different fields of study, as oceanography, microbiology, glaciology, whale research, even the social sciences are represented, in one research center. Here, all scientists are highly specialized and approach the big questions from very different angles.
”The frame work of this center facilitates new research and the emergence of original ideas” explains an enthusiastic Torkel Gissel.”Here we come together and play with these concepts. Professor Hans Peter Grossart from Germany is investigating the genes in the intestinal system of the copepods and Dr. Kam Tang from USA has also joined us at the microscope. He has shown how dead copepods contribute to the movement of carbon down into the sea bed. They might also influence the decomposition of nitrogen. Thus, in this way we conduct a totally different kind of research from what we originally planned and that is research at its absolute best” completes Torkel Gissel.
A significant additional benefit is the cost reduction in both time and money. The object of the studies, Calanus Finmarhius, is out in the fiord, a few meters from the Center. The food for calanus is grown beforehand in the laboratory and the boats and the large guest house at the Institute provide the optimum setting for a creative research environment.
On the door into Professor and Head of Center Søren Rysgaard´s office is a famous quotation of Albert Einstein: “If we knew what we were doing it wouldn´t be research, would it?”
By Kitte Vinter-Jensen, Information Officer at Pinngortitaleriffik/Greenland Institute of Natural Resources
Anni Glud at the microscope Photo: Kitte Vinter-Jensen
Professor Torkel Gissel and Dr. Wang Tang in the laboratory at Greenland Institute of Natural Resources and Climate Research Center Photo:Kitte Vinter-Jensen
PhD Student Kristine E. Arendt grows algae for calanus to eat in controlled conditions in the laboratory Photo: Kitte Vinter-Jensen
Calanus finmarchicus. Photo: Russ Hopcroft, University of Alaska
