We are a group of freshwater ecologists from the Biology Department at St. Catherine University in Saint Paul, Minnesota studying the effect of temperature and nutrient availability on metabolism and nitrogen fixation in geothermally active streams in the Hengill region of Iceland. This is a collaborative research effort with our partners from Montana State University, the University of Alabama, the University of Iceland, and the Institute of Freshwater Fisheries in Iceland. See links to our collaborators labs below.

Thursday, September 19, 2013

10,000 New Ways to Think

Research is a process - it is about discoveries, about making mistakes, taking risks, trying new approaches, and sometimes starting over. We always learn from our mistakes and new approaches, gain some knowledge from the risks, and start over while remembering where we went astray. Thomas Edison once said about the process of inventing the light bulb, “I haven’t failed.  I've just found 10,000 ways that don’t work.” This is the part of research that I love.  I can go to work every day and not necessarily accomplish what I set out to do, but I will have learned something meaningful, even though it may not be what I expected. After days of preparation, packing, and test runs, you get up at 7 am, drive an hour to get to your field site, set up, and run an experiment, and the outcome may be totally unexpected; but, that doesn't mean that the day was a failure.  In fact, through this process of trial and error, we find better and more efficient ways to make our measurements, and ultimately, the outcome and science is better for it!  This process leads us to question our approaches and always be thinking about the unexpected. There are no rules for figuring out an answer, or guidebooks that will tell us in which direction to start. This is why research is such a creative process and requires a lot of flexibility and the ability to think in new ways.

One of the most rewarding experiences that I had this summer was the opportunity to design my own experiment and take charge of all of the details. Curiosity drives research, so I had to first ask myself, what am I curious about?  After the course of a couple weeks in the field using three methods to measure nitrogen fixation, I asked myself, why can’t we use just one method, or what are the advantages and disadvantages of each method, and what can we understand better that will convince us of the accuracy of these methods? Then, I had to devise an array of field measurements using each of our methods that would provide some insight into where the discrepancies between the methods lies. The first day that I was in charge of the field team, I was running on adrenaline, not knowing what the results would reveal, or how the day would go.
I was counting and numbering vials, double-checking supplies, and packing extra everything, just in case. I was the one who had to delegate the tasks and provide the itinerary. I made some mistakes, and miscounted a few vials (which turned out to be a great learning experience in and of itself), but at the end of the day, it was a great success.  I felt accomplished.  We had new and novel data that will help us to better evaluate the methods for measuring nitrogen fixation, which will be an important contribution to the field.  It was gratifying to complete a portion the large international collaborative project that I had designed. It gave me confidence in relying on myself and my own ideas, and brought even more questions to my attention that I hope to pursue in the future as I continue to do more research.

Friday, September 6, 2013

How Did It Get So Late So Soon?

Thumbs up for science!
It’s hard to believe that we are back in Minnesota already. I cannot believe how the time has flown.  It is great to be home, but I found myself having a hard time leaving Iceland. There is so much left to do and experience! I look forward to the day when I can return. The field days are over for now, but the fun in the lab is just beginning.  We were able to accomplish so much this summer and I am looking forward to running samples, as well as analyzing and interpreting the data this fall. 

Four months ago, I would have never dreamed that I would travel to another country for the summer and be able to do cutting edge research with a gorgeous backdrop.  The days were long and sometimes the weather didn't cooperate, but I never felt like I was going to work. I enjoyed the challenges that we were faced with every day and the satisfaction that comes from knowing that no matter the obstacle we faced, we were able to overcome it and find our own creative solution.

One of the final times working with these chambers.  
Oh, how I miss them!

Before this trip, I will admit that I was hesitant and unsure about my abilities as a scientist. This experience has given me the confidence to know that sometimes, more often than not, something isn’t going to work, but I also know that I will figure out how to make it work.  Yes, that is the research process in action and I have a much stronger understanding of the scientific process and the creativity and trial and error involved.

I led an entire research project out in the field this summer; a task I would have never sought out. Prior to this experience, I found myself reading journals and protocols never asking WHY the authors did something in a particular way.  Now, I finish reading an article with more questions than when I started reading.  I think more critically and thoroughly now.   This experience has given me the confidence to understand complex biological processes and has encouraged me to pursue research further. I am excited to begin working with our samples in the lab this semester. I'm eager to see what stories they have to tell us!

Wednesday, July 24, 2013

The TriMethod Tournament

When using 3 methods to
estimate nitrogen fixation, time and
organization of the essence -
and I made sure to keep us on task.
Although it did not involve dragons, mermaids, and hedge mazes full of deadly creatures, we, like Harry Potter in the TriWizard tournament, embarked on a mission that verged on the impossible. It would require skill, perseverance, tenacity, and a little bit of luck.  We have taken it upon ourselves to use not just one, but three different methods in the field to measure nitrogen fixation, which can be intense, especially when dealing with all of them in one day and having to multitask and run them simultaneously. It took all of our focus, along with organization on everyone’s part, to be able to run this smoothly.  Luckily, we had a great team of researchers that worked really well together. I took on the roll of time keeper and task manager and made sure everyone knew what they were doing at which time, because we had time sensitive incubations that were running simultaneously, so there were many things going on at once.

Here, Jill and I are adding 15N2 gas (contained in
the small gray cylinder) to our chambers containing
algae from the different temperature treatments.
Along with the Acetylene Reduction Method (ARA), which I mentioned in a previous post, we were also using a 15N2 method, and a relatively new method called Membrane Inlet Mass Spectrometry (MIMS). All of these methods are a way in which we can measure nitrogen fixation. Unlike the ARA method, which indirectly estimates the rate at which the algae are able to break apart nitrogen gas molecules, the 15N2 method measures the rate at which those nitrogen gas molecules are being incorporated into the biomass of the algae, or, in other words, how much nitrogen did the algae consume and assimilate. In the natural world, there are different “types” of nitrogen atoms, which we call isotopes, but they are exactly the same in every way except they vary slightly in weight. For example, there are 14N and 15N atoms, and in the natural world 14N is much more common in the atmosphere, making it is very hard to track.  In comparison, 15N atoms are very rare, so if we provide a large source of 15N to the nitrogen fixers and they use them, we can use the 15N as a tracer, and track how much nitrogen the algae incorporated into their biomass. So, just like in the ARA method where we inject acetylene into gas tight chambers with algal samples, in the 15N2 method we inject a known amount of 15N2 gas into the chambers instead and allow the algae to incubate for 2 hours to take up this added nitrogen gas where all of the nitrogen atoms are the heavier, and more rare, 15N. However, unlike the ARA method where we collect a gas sample from the chamber at the end, we will directly take the algae from the chamber and use specialized equipment to analyze it for the 15N tracer that we added to the chamber and see how much of it is now in the algae.

It is definitely a coordinated team effort to get all of our
 various chambers set up and running - and in the rain!!
The third method we are using, MIMS, is much simpler in theory, and more direct, than the other methods.   However, the technology associated with this method has only recently become available and it is still very new.  Essentially, we take a water sample from the beginning and the end of the 2 hour incubation with our algal samples. We then preserve the water sample and its associated dissolved gases, which includes N2, and then send it off to be analyzed on a Membrane Inlet Mass Spectrometer (MIMS), which will tell us how many N2 molecules were in the water at the beginning and how many there are at the end. At the end of the incubation, there should be fewer molecules in the water if nitrogen fixation is occurring, as those N2 gas molecules get taken up and incorporated into the algal biomass in the form of proteins and other biomolecules essential for growth.
It's working!  Yes!

So at the end of the day we had spent 10 hours in the field and we were exhausted, but excited to have completed an exceptionally successful day in the field. At the end of the day, I found it to be very satisfying to know that everything that we worked so hard on up to this day had paid off.  And, just wait until you see the data - they are very exciting!!  But, just like the journey of Harry Potter, not all can be revealed at once.  You must wait until the full story unfolds...all in good time.

Sunday, July 21, 2013

Nitrogenase Activity and Temperature

While being here in Iceland, Jackie and I both have a great opportunity to develop a research project.  Over the past couple of weeks I have noticed that particular species of nitrogen fixers are growing in select stream temperatures.  For example, “Rock” Nostoc -  Nostoc c.f. pruniforme (Kützing) Hariot, is only found in colder stream temperatures, while “Pink” Nostoc, - Nostoc spongiaeforme Agardh ex Born Flah, is found in warmer streams.  It was interesting to see such a distinct species preference to temperature.  I started to wonder what would happen to these species if the stream temperature that they are acclimated to were to change.
"Rock" Nostoc - Nostoc c.f. pruniforme
            It is well documented that global temperatures are increasing (NASA 2013). All organisms, in general, have several physiological processes that are regulated by temperature-dependent enzymes including cellular respiration, photosynthesis, and for a special group, nitrogen fixation.  Enzymes have a threshold for both cold and hot temperatures. As Jackie mentioned in the previous post, The Number, a select group of organisms have the ability to obtain and use nitrogen gas from the atmosphere, which is unavailable to non-nitrogen-fixers. These organisms are called cyanobacteria and they have a specific enzyme, called nitrogenase, which allows them to do this.  Nitrogenase functions to break the triple bond in nitrogen gas to yield ammonium, which is then used by the cyanobacteria to build biomolecules essential for growth.  Fixing nitrogen is an energetically expensive process and, therefore, not advantageous in nitrogen-rich environments.  However, the streams we are working in are not nitrogen rich, and many species of cyanobacteria are definitely present, with some clear shifts in species composition across the temperature gradient.  Given these observations, I began to wonder, how does temperature affect nitrogenase activity in different aquatic cyanobacteria species?  Is the rate strictly driven by temperature, or have these species adapted to certain stream temperatures in ways that lead to differing relationships between temperature and nitrogen fixation rates among the different species? Can cyanobacteria found inhabiting cold streams rapidly increase nitrogen fixation rates in warmer streams and vice versa?
            In order to investigate this question, we will be doing a reciprocal transplant experiment. We will collect dominant cyanobacteria (mostly Nostoc pruniforme) found in cold streams (~10˚C) and transplant them into both colder (~5˚C), warmer (15˚C), and hot (25˚C) streams. We will do the same for Pink Nostoc - Nostoc spongiaeforme, whose resident mean stream temperature is about 15˚C, as well as other dominant cyanobacteria species.  By the end of the transplants, cyanobacteria from each of their resident streams will be relocated to other streams spanning this temperature gradient, with 5-6 replicates for each species. I know I mentioned previously, that temperatures are increasing, so why put samples into colder temperatures?  Assuming nitrogenase reacts to temperature like other enzymes, its activity rate should decrease in colder temperatures and increase in warmer temperatures, up to some threshold.  Placing the dominant cyanobacteria species across a wide temperature gradient and measuring their nitrogen fixation rates will help us to better interpret and understand the relationship between temperature and enzymatic activity and where and under what conditions we should find each species.
"Pink" Nostoc - Nostoc spongiaeforme
  The goal of this experiment will be to see how these different species respond to different temperatures, and their ability to acclimate to a new environment. It is important to know the temperature threshold these species can withstand and how nitrogen fixation rates are likely to change in a warming world. If their temperature threshold is limited, it might be possible that in coming years, community composition will shift due to rising temperatures which could lead to species being out competed or lost entirely. Nitrogen-fixers play an important role in ecosystems where nitrogen is limited because they provide a source of nitrogen for other organisms, which feeds back on the ecosystem as a whole by influencing photosynthetic rates, the production of invertebrates and fish, and how other elements like carbon and phosphorus cycle as well.

Sunday, July 7, 2013

"The" Number

We found algae!
We finally had some decent weather after days of rain and wind, and we were able to go out and make our first measurements of nitrogen fixation on the tiles associated with the channel temperature experiment. Algae (and all photosynthetic organisms) typically acquire their source of nitrogen from the soil and water around them, but some species, called cyanobacteria, are able to acquire it from the atmosphere. The species that can do this have an enzyme called nitrogenase that can break apart the two nitrogen molecules in nitrogen gas (N2), the most abundant gas in the atmosphere. They then use the nitrogen to build amino acids and other nitrogen containing molecules for growth. 

This summer we are planning to measure nitrogen fixation with three different approaches as a comparison of the methods, as well as to use them as a check against each other.  For
Chemical conversion of nitrogen fixation (left) and
how it compares to acetylene reduction (right).
our first sampling day, we only used one method, which is called the Acetylene Reduction Assay, or ARA. The ARA method involves making acetylene gas, which we do in the field using calcium carbide and water in a flask, and then collect the gas in either a balloon or syringe. We then inject the acetylene gas into gas-tight chambers with the algal samples and then take an initial and final sample of the gas in the chamber. During the incubation the algae in the chamber are breaking the triple bond between the two carbon atoms in acetylene to produce ethylene (see diagram), which is similar to the chemical reaction in nitrogen fixation (see diagram), and we are able to measure production of ethylene gas and use this as a measure of how much nitrogen the algae are fixing. 

Working on getting "the" number.
Over the years, the ARA method has been modified and refined for better results while still trying to keep the procedure fairly simple. This summer, we are collaborating with another project and we are measuring nitrogen fixation on tiles that have been colonized with algae.  As part of this effort, we had to modify the ARA method again for use with custom chambers that were built for the project. This came with several challenges that involved some creative thinking and problem-solving skills, which are essential skills to have when conducting research. The physical act of research is easy; going out in the field, collecting data using technical instruments, putting samples of water and algae into vials, and following previously thought out methods.  However, it is naive to think that’s all there is to research. As Jill always says, “It’s easy to get 'a' number, but more challenging to get 'the' number”. What she means is that it’s easy to go out into the field, spends hours collecting data, and reading numbers off of instruments, but the hard part is deciding what that number tells us, and if we used correct and precise methods for obtaining the actual number that represents part of the answer to our question. For example, when we are trying to figure out how to make gas-tight chambers we have to think like a gas molecule and really channel our inner Sherlock Holmes to make sure we are getting good data, but at the same time not be biased.

So far, our research has been really frustrating, impossibly complicated, and infinitely
Excited after a day in the field of
hiking and looking at algae.
rewarding. I love a good challenge and this research is important in helping us understand how whole ecosystems work, which we can then use to help gauge how they are going to be affected by human activity. There is still so much we don’t know about our world and the ecosystem services we depend on for survival. I am starting to see how easy it is to build an entire career’s worth of work in research. I feel invested and driven by curiosity and I am really looking forward to seeing where it takes me.

Friday, July 5, 2013

"Re" Search

The last couple of days have served as a great reminder that when a problem arises with a critical part of an experiment, rarely is there a single solution. I thought that when an experiment was about to begin, all of the details were worked out, and the only tasks left were to collect data and analyze it.  Wrong. It has been said on several occasions that “once you smooth out the kinks, data collection is a breeze”. Finding the kinks is easy; it’s the solution that’s tricky.
The 300mL chamber that will be used
 to measure nitrogen fixation
One of our methods requires the use of an air-tight chamber. On the surface, it sounds like an easy task. Only once you try to actually make a chamber air tight do you realize the difficulty.  In our collaboration with Tanner Williamson, we are using chambers that have been designed especially for this experiment. These chambers hold only about 300 mL of water, which is ideal for measuring biological processes on a small amount of algae. The small chamber volume is important because the tiles that we are measuring nitrogen fixation on are barely a cubic inch in size. The added bonus of these chambers is that it has a recirculating fan that circulates the water within the chamber and mimic stream movement. The double-edged sword is that these chambers only have one opening. The chambers that were used in our work last year had two openings; however, those chambers were much larger (2 liters) which makes measuring nitrogen fixation more difficult. The benefit of having two openings comes into play when we are required to simultaneously add gas and remove water using two different ports. These new chambers posed two problems: being air-tight and only having one opening.
Deciding to address the gas-tight issue first, we attempted to cap the opening of the chamber with a rubber septum. It turns out that this is extremely hard to do, as you are essentially forcing an object against a positive pressure gradient. Even though we managed to get the septum on, the chambers were over-pressurized and some airspace remained inside the chamber. Plan B involved a simpler method. Underwater there should be no air, thus removing the problem of trapping air inside the chamber and over-pressurizing. Placing the septum over the top of the chamber while the septum and chamber are submerged creates a chamber that is free of air.
Using a chamber with only one opening has a few challenges within it. We are required to add gas and remove water at the same time for one of our methods. This technique becomes difficult to do when the only way into the chamber is through the septum at the top (about the size of a quarter). Two insertions (one for the gas, the other for the water) requires two people. We also have to insure that we are not pulling out the newly injected gas as we are removing water from the chamber. We then had to address the issue of which insertion would work best for injecting the gas. In other words, should we inject the gas at the top of the chamber or at the bottom? To answer this, we added blue food coloring to the chamber, with the fan running, and observed the flow pattern of the water. The food coloring instantly moves toward the fan and begins to dilute.  Based on this, we decided it would be most beneficial to add the gas at the top of the chamber and pull the water out from the bottom.
     Several hours of critical thinking mixed with trial and error resulted in these problems being solved. At the end of the day, it is extremely gratifying to have created a solution to a problem that at the beginning of the day seemed unfix-able.   These challenges have helped me to understand that critical thinking and creativity go hand in hand during research. 

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.
 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"