We are a group of freshwater ecologists from the Biology Department at St. Catherine University in Saint Paul, Minnesota. Our research takes us to Iceland and other arctic regions where we are working to understand how temperature influences nitrogen fixation rates and metabolism in cyanobacterial assemblages. Nitrogen fixation is extremely sensitive to temperature and therefore nitrogen gas from the atmosphere may become more accessible to freshwater ecosystems as the climate warms. We are working to understand the potential ecological and environmental implications of changes in cyanobacteria species composition and nitrogen fixation rates in arctic lakes and streams.

Thursday, January 23, 2014

Exploring Hengill: January 2014

I can't believe that our time in Iceland is almost over.  We have been here just a short time, but we have accomplished a great deal.  We knew that the winter trip would be difficult and every step of the way I was happy that we were well prepared for whatever the weather would bring.  We had enough clothes, food, water, and all of the gear needed - nothing was forgotten - whew!  That certainly helped, but every day was labor intensive and the conditions forced us to be on our toes both mentally and physically. 

The week started with the truck ride of a lifetime with Sveinbjörn Steinþórsson from the Institute of Earth Sciences at the University of Iceland.  It is his job to monitor seismic activity and status of glacier growth and retreat in Iceland and with a job like that, you need a truck that can go anywhere.  It was amazing!  The truck was outfitted with every technological gadget you can imagine, as well as a souped
up hydraulic system to raise and lower the vehicle, and an internal air compressor to fill the tires, after emptying them to help better hug the snow on the mountainous terrain.  It was a blast and we were fortunate to have Sveinbjörn's assistance in getting to our study site as it had just snowed and it was a challenging trip, even for the super jeep.  The snow was very light and grainy and wouldn't stick together, making it difficult to get traction.  But, we made it no problem with the assistance of our experienced guide and enjoyed the ride and the adventure. 

We arrived at the doorstep of our home for the week  - a scout hut that was built during World War II called Þrymheimr (ThrymrThrym; "uproar").   The cabin is named after Þrymr, who is said to have stole Thor's hammer to extort the gods into giving him Freyja as his wife.  However, his plot was foiled by the gods and eventually Thor killed Þrymr - the story of how Thor got his hammer back is told in the poem Þrymskviða.   The cabin is full of character with old wood and 11 bunk beds that are used by scouting groups throughout the year.

The high winds had packed in the front door with snow, so we had to do a little shoveling to extract our entrance, and we were excited to get inside with all of our field gear and equipment and set up shop.  The cabin has no electricity or running water, but it does have a very small fireplace and a diesel heater.  However, the winds were so high the first two days that the gusts would come straight down the chimney and blow out the flame in our diesel heater.   We did what we could with the fireplace, but the damp conditions made it difficult to even get paper to light, let alone our damp wood.  So, we were a bit extra cold the first night and I don't think any of us took our mittens off for long.   We did try a short game of Yatzi by the fire, but I am still learning how to play and I gave up after a bit, but it was fun to sit by the fire and relax a bit after out trek in.   After the second day, the winds subsided and we were able to use both the heater and fireplace and it felt almost luxurious! We joked about the incredible spa treatment in the sauna-like conditions - but really, it was still pretty cold (maybe in the 30's - Fahrenheit that is).    

Aimee and Jackie standing in streams 7 (left)
and 8 (right).
The first hike into the Hengill Valley was probably the windiest of the week - you definitely had to have your goggles on to protect your eyes from the pounding sleet, but at the same time, it was incredibly beautiful.  Due to the fresh and loose snow, our feet broke through the surface quite a bit and we got a good workout with lots of highsteps as we pulled our legs forward through the deep layers.  So, it wasn't an easy hike, but the views were fantastic and the sunrise was a welcoming sight.  The weather improved throughout the day, as well as the rest of the week.

Our first task on day one was to do some exploring - to revisit our study streams, which up until now, we had only seen in the summer.  Now, many of them were covered with snow, and we had no idea what kinds of algae we would find, or if nitrogen fixers would be present under such dark conditions.  First along our path, we encountered streams 5 and 6 - two of our warmer streams.  We jumped in and scanned the rocks - not much algae in stream 5 and little sign of cyanobacteria.  But stream 6 was another story - we noticed the black tinge to the rocks right away - some kind of cyanobacteria, but it wasn't immediately obvious what species we had.  I can't wait to get those samples back home so that Dr. Paula Furey can take a look at them under the microscope and help us determine what it is!

Then, we hiked on to streams 9 and 10.  Both were covered with snow and we chose a couple of spots to carefully dig holes to get a look at the streams below.   In fact, as we hiked across the landscape, we had to be careful where we stepped and to anticipate the locations of the streams and holes underneath the snow so that we didn't fall through.   Amazingly enough, the first holes that we dug on both streams 9 and 10 revealed rocks covered with Nostoc pruniforme - and they looked healthy and thriving.   So, the week was off to a great start.  We now know that cyanobacteria are thriving under the dark and snowy winter conditions in the Hengill Valley - but what are they up to under all of that snow?  More on that soon....




Fashionable Dishwashing Gloves - Great for Field Work

Very fashionable red and yellow rubber gloves.
 This past week we had a chance to do winter sampling in Iceland. We were using methods that we used in the summer to once again measure nitrogen fixation in streams in the Hengill watershed in Iceland, but this time we were in some different weather conditions. While we were out in the field we experienced rain, snow, sleet, and plenty of darkness that we had to learn how to work with. The sampling methods we use are very labor intensive and can be challenging in any weather, and even more so in harsh conditions. Yet, by the end of the week, we were pros at dealing with variability in weather. We also learned that trash bags, rubber gloves that go up to your elbows, ski goggles, face masks, and dish washing gloves can be very fashionable.
Snow sculptures - a good activity while waiting for our
sample incubations.
    Many of the streams were completely or partly covered with thick sheets of snow.  Once we dug down to where the stream was, the snow was sometimes over our heads. It seems odd that photosynthetic organisms, which rely on the sun, are still surviving, even thriving, under six feet of snow, but this added to our curiosity and fueled us to find out what they are doing under all of the snow.
    Snow seems to bring out the kid in all ages.  While spending everyday outside surrounded by snow, we seemed to find ourselves engaging in some "snow fun" during periods of down time while our samples were incubating.  We constructed our favorite snow animals, built a snow castle, and engaged in some snowball throwing and shovel sledding.  It really is hard to not love snow. 
Yes there is a stream down there -
and yes we found nitrogen fixers!
    Currently we are running samples back at the lab and working towards finding out if the nitrogen fixers we encountered under the snow are fixing nitrogen from the atmosphere under the most extreme winter conditions and hopefully will have part of the story soon. Our trip this January is a short one and is going by very fast, so we are working very hard to make sure we get everything done before we leave that needs to be completed.




Sunday, January 19, 2014

We Have Returned from Field Sampling

A quick update - we have returned from our six day sampling trip in the Hengill region and all is well.  We had a great week and we have many stories to tell through the blog in the coming days.  Until we get a chance to do some writing, enjoy our new photo album above from our amazing week.

Sunday, January 12, 2014

What We've Been Up To

This last semester has busy with lab work and data analysis. Working in the lab for an extended period of time was a new experience for me and after spending the majority of my day in the field for an entire summer, it took some adjusting. When we returned to Minnesota, we had dried algal samples that needed to be prepared for analysis. This consists of taking a small amount of the dried algal sample, pulverizing it into a fine powder, then measuring out a microgram of powder to be put into a tiny tin capsule and finally using forceps to manipulate it into a ball shape. At first this process was daunting, taking me several minutes to complete just one sample, but toward the end, I could finish a sample in under one minute. These samples are extremely important because they will show how much N15 was incorporated into the algal biomass which will tell us how much nitrogen it fixed. Once we had this information, we were able to start our data analysis. There is nothing more exciting than to see hours of hard work in the field morph into data points which ultimately turn into a graph that represents an entire project. I enjoyed the challenge of trying to interpret my data and to better understand the story they are trying to tell. 
We are currently back in Iceland for two weeks to see what species of nitrogen fixers are present and at what rate they are fixing in a winter environment. This past week we have been packing our gear and triple checking to make sure we have everything we will need. We will not be able to drive into our field site everyday, like we did in the summer.  Instead, we will be driven in by a super jeep to a remote cabin in Hengill where we will stay for five days. This cabin will not have electricity or running water which will definitely make this trip an adventure.