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.

Tuesday, June 25, 2013

Latitude 66

Jill, Jackie, Aimee, Allison, Mara, Kyrstin & Anika
It was bittersweet as we left the familiar community of St. Kate’s as some of our fellow friends and classmates (Allison Hutson, Mara Blish and Kyrstin Danielson, alumna Anika Bratt, who is now a graduate student at the University of Minnesota) came to help pack up, get us to the airport, and even help carry our 14 containers to baggage check. We were all geared up and on the plane, and as we took off, we got a clear view (after much rain) of the human-dominated landscape we call home.  It wasn’t long before I looked out my window and saw the Great Lakes followed by the vast open spaces of northern Canada covered in snow and ice.  After several hours flying over the ocean, which was largely blocked from view by clouds, the coast of Greenland began to come into view. Contrary to its name, Greenland is covered with the largest expanses of
Sunset over Greenland
snow that I’ve ever seen.   Although we didn’t have seats facing the sunset, the other side of the plane provided views of a sky striped with shades of blue, purple, and pink that illuminated the clouds as the sun set.   Almost immediately, the sun rose again and the tips of the mountains in Greenland were lit up by the bright sun.    We did not view land again until we ducked down out of the thick clouds and got our first look at Iceland and its moonscape-like quality. 


Since we have been here for several days now, I have had a chance to see more of the unique landscape of Iceland.  The island is geologically young and was formed from volcanic eruptions from a giant volcanic hot spot that sits on the ridge of the Eurasian and American tectonic plates, which are constantly moving away from each other.  This volcanic island has geothermally-heated pools and streams that are naturally warmed as water flows underground through heated rock, warming the water before it emerges at the ground surface.   Iceland is also located close to the Arctic Circle, with the capitol Reykjavík positioned at a latitude of 66° north, where it does not get very warm, even during the summer.   At this high latitude, Iceland experiences incredibly long days during the summer months and even though the sun sets for a couple hours, it never gets truly dark.   This midnight sun allows the locals to take advantage of being outside as much as possible.   

Iceland is certainly also a very unique place to study from an ecological standpoint.  Since the island is so young, the volcanic basalt is very phosphorus-rich, suggesting that the growth of many organisms here is not limited by available phosphorus (an essential nutrient for growth), but instead constrained by a lack of available nitrogen – another essential nutrient.  This provides a good environment for researching nitrogen fixers, which are bacteria that can acquire 
Fields of lupine cover the hillslopes within the city and
surrounding area, all along our drive to the field site.
nitrogen from gas in the atmosphere rather than the surrounding  water, land, or fertilizer in more human-dominated ecosystems.  Here in Iceland, it appears that there are nitrogen fixers everywhere, including the streams (which we will focus our studies on this summer), and even in terrestrial environments - such as the lupines and lichens, and even the mosses, which are very abundant here - all contain or house bacteria that can fix nitrogen from the air.  They are everywhere!

Monday, June 24, 2013

The "Less is More" Approach

The kitchen Jackie and I share 
Upon arriving in Iceland, one thing became apparent immediately. Everything is much smaller. To an American, everything about our apartment is compact and “fun size”. The bathroom appears to be built inside of a storage closet, my bed is the size of a couch, and American hotel rooms have bigger kitchens. We pride ourselves on our space; open living rooms with hardly any furniture, king size beds, and large bathrooms. We, unfortunately, disregard the impact these “necessities” have on our environment. 
Environmental impact is at the forefront of Icelandic thought. This became clear very early in our travels. We were asked to reuse our cups on the flight in an effort to reduce the amount of waste produced. We learned that you will be charged if you need a bag to put groceries in, which encourages people to reuse bags instead of throwing them away. An average cup of coffee here is the same size as a small cup in the U.S. 
My bed for the next 7 weeks


It is not difficult to get around Reykjavík by biking or walking, which helps reduce the amount of waste within the city. Even the garbage cans are smaller here, which helps you recognize just how much you are throwing away. It appears that the choice to be more efficient is collective in Iceland; it’s a way of life not a lifestyle. The idea of preserving the landscape and reducing environmental changes is deeply embedded in Icelandic society. It is a huge shock to be immersed in a culture where “less” does not mean less quality, it is simply less wasteful. 

It is common to hear conversations about reducing waste and terrain conservation, but rarely do you hear about a place where these two ideas are actually carried out. Living in the United States, where the population is large, it can be difficult to believe that one person’s choice to be more eco-friendly will have an impact. It is wonderful to be in a country where this actually happens. Witnessing a country that successfully incorporates these two ideas into its society has changed my perspective on the likelihood that the same can be done holistically in the United States.  

Friday, June 21, 2013

Field Work Begins with an Exciting Experiment

Meet Tanner Williamson - a graduate student from
Montana State U. and his channel experiment.  We will be
working closely with Tanner and undergraduate student
Ellie Zignego to pair N2-fixation measurements with
estimates of algal metabolism and nutrient uptake.
The 2013 field season has officially begun for the St. Kate's crew.   This year, we are working closely with the Montana State team led by Tanner Williamson, a graduate student who is conducting an elegant experiment that will assess the effect of increasing temperature on algal species composition, biomass, and metabolism, as well as nutrient content.  Tanner has been in Iceland since early May and has been working with the University of Alabama team (Phillip Johnson who designed and built the heat exchangers and Alex Huryn who designed and built the incubation chambers) to get this experiment set up and operating well as the peak summer growing season approaches.  We will be working with Tanner to support his measurements and help out wherever we can.  We will also piggyback onto his data collection and measure nitrogen fixation rates during each sampling period so that we can compare nitrogen fixation rates with Tanner's estimates of photosynthesis and respiration across the temperature gradient, as well as the uptake rate of essential nutrients from the stream water, including nitrogen and phosphorus.  

Experimental channels with 5 temperature treatments -
ambient, +5, +10, +15, +20 degrees C.
Three
 channels are maintained at each temperature.
In this experiment, cold water is piped from a nearby cold stream (~ 6 degrees Celsius) and split into 3 separate faucets so to speak - one that remains cold, a second where cold water is passed through a heat exchanger that sits in a warm pool (~ 25 degrees C) which warms the water as it passes through coiled tubing within the pool, and a third pipe that runs the cold water through a heat exchanger sitting within a boiling hot pot (~80 degrees C).   These three "faucets" are then used to create a temperature gradient comprised of 5 temperature treatments - ambient (temperature of the cold stream), +5,+10,+15, and +20 degrees C.  Water at these set temperatures is then piped into small artificial channels, with three channels maintained at each of the 5 temperature conditions, for a total of 15 channels.  These little channels require quite a bit of maintenance on Tanner's part to keep the flow rates consistent and to ensure that the mixing of water from the various inlets maintains the appropriate temperature gradient.  So far, they are working extremely well and have remained steady with consistent temperature increases across the treatments.
Close up of basalt
tiles in the channels
First field day measuring metabolic rates associated
with algae and microbes that have colonized the tiles
after 4 weeks.  It was quite rainy and windy!

We arrived just before the first sampling period, scheduled for 4 weeks after Tanner had placed clean basalt tiles into the channels to provide a colonization surface for the resident algae and microbial community.  Upon inspection you could see that the tiles were beginning to turn green, with a visible effect of the temperature treatments, so it was time to collect the first initial set of data.  Our first planned field day was canceled due to bad weather, which has to be pretty bad to cancel a field day (it was very foggy with low visibility and lots of rain), but we have been out in the field for the past 3 days now and we been fortunate to have sunny skies for the most part.   The first day we measured photosynthesis and cellular respiration on sets of tiles from each of the experimental channels, followed by nutrient uptake (both nitrogen and phosphorus) yesterday and today.  It has simply been beautiful out - so nice in fact, that one might be tempted to think that you no longer need to bring heavy rain gear to the field.  Ah....but one should never give in to such thoughts at Hengill, as sunny skies can turn to cold wind and heavy rain in a blink of an eye!
Beautiful sunny day with Ellie, Tanner, Jill, Aimee,
David and Jackie.  Tile sampling, day 2.
We are also in the process of setting up our gas chromatograph and we expect to measure N2-fixation on the tiles early next week.  So, we are off and running!  More from Aimee and Jackie soon - when they can get a break from field work - but on such a beautiful sunny day it is best to be outside!  In the meantime, hope you enjoy our new slideshow (above) with some  photos from our first week.





Monday, June 17, 2013

We Have Arrived: Fixation on Ice Take Two - 2013

View of the edge of Greenland from the flight
to Iceland.  Photo by Jackie Goldschmidt.
Yes - we have eagerly and successfully returned to Iceland for Nitrogen Fixation on Ice Take Two!  And, I am excited to report that we arrived safely with our 14 checked containers (yes 14 this year!) ready to hit the ground running.   After a busy spring and recent presentations of our work from last summer at the Society for Freshwater Science conference (see posting below), we quickly packed up our gear with some new supplies that will be part of an exciting and elaborate field experiment (more on that later this week).  Aimee Ahles and Jackie Goldschmidt, the two new SCU student participants for summer 2013, did the bulk of the packing and organization and they were invaluable in getting us ready for this year's research adventure.  They will introduce themselves and their experience so far in the coming days.  

We departed at 7:30 pm on June 15th and arrived yesterday at 6:30 am after a spectacular flight over northern Canada, across Greenland, and into Iceland, ending with a smooth landing in Reykjavik.  The most difficult part of the trip was getting our 14 heavy containers full of field and lab gear onto carts and out the doors through customs with just the 3 of us to move it down the narrow corridor with its several sharp 90 degree turns on very little or no sleep.  But, it is hard to sleep when you are flying over such a breathtaking landscape.  It is almost hard to believe
Arrival at Keflavik Airport
it's real!  And, the views are so dynamic, changing minute by minute, it makes it nearly impossible to look away.   I was lucky enough to have a window seat on the north side of the plane with the most amazing views from the edge of the planet at 37,000 feet - not to mention the fact that as we near the longest day of the year in the northern hemisphere - I was able to observe the longest sunset with the most beautiful array of reds and oranges that saturated the clouds below us.  The thick cloud bank absorbed the color in a blanket of light as the sun sank further on the horizon while the clouds dissipated over a period of an hour or so.  Then, just like that, the sun set....for about 15 minutes......and then the sun began to rise and the colorful show played in reverse.  It was simply incredible.  We were also fortunate that the clouds dissipated on the western and eastern edges of Greenland, revealing the rugged mountains and massive expanses of snow and ice, as well as the impressive chunks of floating ice in the surrounding ocean water.  Gratefully, Jackie took some great photos from the south side of the plane as I sat in my seat many rows away, wishing desperately that my camera wasn't tucked away in my bag!  Never again!  
Summer 2013 Crew - David Hernandez (U of Alabama),
Aimee Ahles (SCU), Lillian Benstead (youngest member at 5 years of age),
Tanner Williamson (Montana State U.), Jon Benstead (U of Alabama),
Jill Welter (SCU), Jackie Goldschmidt (SCU),
Dan Nelson (U of Alabama), and Ellie Zignego (Montana State U.)
Jon Benstead (from the University of Alabama) was nice enough to make the drive to Keflavik Airport early in the morning to meet us with all of our gear and help us transport it to the lab.  I was also happy to see that I remembered the routes and roads fairly well and we were able to navigate around the city with ease and get settled into our housing after freeing ourselves from those 14 heavy containers!  Jon and his family (Heidi and daughter Lillian) also invited the whole research crew over for dinner last night and we were treated a feast of roasted lamb, potatoes, and wild mushrooms, followed by a Nerf (foam toy) gun target competition, which apparently is becoming tradition at the Benstead household.  I am also proud to report that the SCU team performed exceptionally well with no sleep and Aimee took first place - a high honor within this crew!  So, all in all, we are off to a great start and we are enjoying spending some time with the team we will work with this summer, which is composed of some returners from last year and some new participants.  It is shaping up to be a great summer!  

Today was Independence Day in Iceland and we enjoyed a great variety of games, plays, and music being performed in downtown Reykjavik, and tomorrow our field work begins.  We leave for the field at 8 am, but we will have more blogs coming shortly, with more details about our trip here, first impressions of Iceland, and our work ahead.  So, stay tuned!  And, thank you, thank you to all of our friends, family, esteemed alumnae and the St. Kate's community that have supported us and made this trip and research project possible.   We will certainly make the most of this opportunity!  Takk fyrir!

Society for Freshwater Science Conference in Florida

The St. Kate's Crew at the Society for Freshwater Science conference - left
to right - Paula Furey, Delor Sander (standing), Jill Welter, and Anika Bratt
In late May, we traveled to Jacksonville, Florida to present the first results from our collaboration in Iceland to the scientific community.  Overall, the Iceland project group gave six presentations, including three from those of us representing St. Kate's.    A fourth presentation also focused on nitrogen fixation was given by a recent St. Kate's alumna - Anika Bratt who is now a Ph.D. student and continues to study nitrogen fixation in the Eel River in California with Jill Welter and Paula Furey as collaborators, as Anika has been following up on some research questions she developed as an undergraduate student at SCU.   All of the group's presentations were well-received and we gained a great deal from our conversations with colleagues in the field, as well as a chance to meet up with our project collaborators and spend more time exploring our collective findings.  Delor gave a presentation focused on a comparison of two of the methods we used to measure nitrogen fixation in Iceland last summer and all reports indicate that she did an outstanding job and took advantage of the opportunity to talk one-on-one with other key scientists who are using similar approaches.  They expressed great interest in our data and initial results  - a great way to lead into our upcoming field season in Iceland which will give us the opportunity to follow up on the feedback we received at the conference. Here is a list of presentations given by our project group:
Delor presenting her poster at SFS - pictured here with
J.S. Ólafsson and 
G.M. Gíslason - our collaborators from Iceland,
and Jim Hood from Montana State U. (left to right).

Delor Sander et al. "Predicting effects of climate warming on N2-fixation and its ecological consequences in aquatic ecosystems:  a comparison of acetylene reduction and 15N2 isotopic methods"

Jill Welter et al. - "Effect of temperature on N2-fixation rates and N2-fixer species assemblages in streams in the Hengill region of Iceland"

Paula Furey et al. - "Composition and abundance of nitrogen-fixing algal assemblages in nitrogen-limited streams along a geothermal gradient in the Hengill region of Iceland"

Jim Hood et al. - "Patterns of nitrogen and phosphorus uptake across a thermal gradient of subarctic streams"

Jim Junker et al. - "Patterns of epilithic CNP stoichiometry across a natural temperature gradient in Icelandic streams"

Dan Nelson et al. - "Experimental whole-stream warming increases algal standing crop but reduces consumer biomass"