Our teacher said that you did an expedition in August, why did you
choose Svalbard?
The project we have "PAME-Nor: DOC turnover in polar microbial food webs." Is a project under the International Polar Year (IPY) so to get funded we have to do research in polar regions. Ny Alesund on Svalbard is the northernmost permanent settlement on earth. It was established as coal mining town but is now only a base for scientific stations. So Ny Alesund is an ideal place for us to do field work in the arctic. You can find a map and many nice pictures from Ny Alesund at http://loonen.fmns.rug.nl/arctic station/towninfo.htm

And here you can read more
http://www.kingsbay.no/bins/site/templates/splash.asp

The work we did this year was a so called mesocosm experiment (meso = medium, i.e a medium sized cosmos).

We filled 10 plastic tanks (mesocosms) with seawater and manipulated them with nutrients (nitrate, phosphate and silicate) and glucose
(carbon source). The purpose of the experiment was to investigate how bacteria and phytoplankton compete for nutrients (N and P).
The underlying hypothesis is that the ecological mechanisms controlling supply of dissolved nitrogen and phosphorous - rather than
the low temperature - is the main mechanism restricting bacterial activity in cold waters as we believe it is also in temperate and
warm regions.

In the attached powerpoint you can see some pictures from the experiment and some of the team at work. This year we were 13-16
participants (some returned when the instruments were installed)

- In general, how long does an expedition take?
"Expedition" sounds very bold - we use to call it "field work", "field experiment" or "cruise" (when we are on a ship). In any case
field work use to last 2-3 weeks, seldom 4 weeks.

- How many expeditions do you do every year?
Two times a year at the most. Each field work generates a lot of samples and data that must be analyzed when we are back home in
the lab and that takes several months.

- How do you collect plankton?
Depending on what kind of plankton and for what purpose we sample.
For zooplankton we may use a net with mesh size (i.e. holes) 60-100 µm (1 µm = 0.001 mm) if we need a large volume
(e.g. for measuring dry weight).

For phytoplankton we use different kind of filters with pore size 1 - 10µm.

Phytoplankton, bacteria and virus (yes bacteria and virus are plankton too) can also be analysed (counted) just by adding a few ml
of seawater to some instruments called flow cytometers. That is we don't have to collect the plankton, we just take a water sample
and analyze it.

- Does plankton have a particularity in polar regions?
You will find different species in polar regions compared to temperate and tropical regions and they are all adapted to the
environment and temperature they live in. In cold water they will typically have fatty acids and proteins (enzymes) that work
better at low temperature, but I don't think they otherwise are very different from those you find in warmer water.

- Why did you choose this job?
I was interested in biology and ecology at high school and I started to study biology at the university. A series of coincidences
(e.g. the popular classes in zoology and marine ecology were full) made that ended up studying microbiology and microbial ecology.
The teachers were great and I had a good time so I was hooked. I took my masters, got a PhD position and stayed on and now my
teachers are my colleagues. In sum, I have done things that I liked and stayed where I found people that where fun to work with.
When you have a good time you will also do a good job.

- Are you working alone or with other researchers?
We have a research team of 14 -16 people (professors, researchers, postdocs PhD students etc). You can find info and images
on our www site:
http://www.bio.uib.no/pages/forskergruppe.php?gid=1012&lang=E

- What's your craziest discovery?
My greatest discovery is that natural seawater is full of viruses, more than 10 millions pr mL or 10 000 000 000 per liter. Back
in 1988 there were some suggestions that virus infecting bacteria (so called bacteriophages) might play a role in natural ecosystems.
Some colleagues and I figured out that if viruses were important it should be possible to see them in the electron microscope
and if we couldn't find them they must be so few that they didn't matter. So we modified the method we used to prepare bacteria
for electron microscopy and with some trial and error we found virus all over. The story was published in the high ranking
scientific journal Nature. Now there are a lot of scientists around the world that are working on different aspects of viral ecology
and we now know that virus play a major role in controlling the marine microbial food, population dynamics, diversity and even climate.

- Have you ever been to Reunion Island to study plankton?
No, but if I had the opportunity I am sure it would be interesting.