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.

Wednesday, July 25, 2012

"I Love the Smell of Calcium Carbide in the Morning!"

Getting ready for chamber
incubations in the field
We successfully measured nitrogen fixation rates in the field last week using the acetylene reduction method.  It was great to be able to see our efforts come together and to be able to make actual measurements in the streams.  One of our methods utilizes calcium carbide to generate acetylene gas, which we collect in a balloon that we then pop to release the gas, after it has been sealed within our gas-tight chambers.  This technique allows us to measure nitrogen fixation rates because the of similar structure of atmospheric dinitrogen (N2) gas and acetylene, which "tricks" the nitrogenase enzyme into converting acetylene into ethylene.  After releasing the acetylene gas into the chambers, we collect gas samples over time and then measure their ethylene content on a gas chromatograph.  We then use the rate of ethylene production to estimate nitrogen fixation rates.  We had great fun generating acetylene gas in a side arm flask and filling a balloon with it.  Unfortunately, it was a little windy and rainy, making it challenging at times – something to get used to with the capricious weather in the Hengill watershed.   The calcium carbide has a unique smell (like old, sweaty gym socks, yuck!), which Bayley enjoyed, prompting the title to this blog entry.  After generating the acetylene, I got some practice collecting gas samples from the chambers, and more practice working with the gas chromatograph when we got back to the lab.  We also processed our algal samples from the chambers, and we will have some precise nitrogen fixation values to compare shortly.   The story behind each of the unique streams we are working with is just beginning to unfold.  The algal diversity between streams is striking and it’s clear at first glance that there are some distinct changes in species composition along the temperature gradient.  It seems like we have some powerful nitrogen fixers inhabiting the streams!  It has been great to get our field measurements going, as working with these methods out in the streams is different from doing them in a lab, and we are still a little clumsy, especially with the challenges presented by the constantly changing weather conditions.  It is very fulfilling to know that we are beginning to put all of our preparations into full use, and that the time we are spending troubleshooting will pay off in a tangible way very shortly.
Dr. Welter with a
chamber full of Anabaena
Me with incubating chambers
Chamber with
acetylene balloon




Monday, July 23, 2012

Positive Identification!

Enteromorpha inside a metabolism chamber
Dr. Welter and Dr. Jim Hood (the postdoctoral researcher running the field project here in Iceland as part of the U.S. team) took me and Delor out to the field to practice the chamber metabolism procedure and run through the field protocol step by step.  The field day was a practice run that would allow us to become familiar with the chambers, get an understanding for how the algae would respond to the chamber conditions, and to collect some samples to observe under the microscope for species identification.  The research team that we are collaborating with here has been placing tiles with attached algae inside the chambers, so the algae are largely stationary and fixed to the tile.  However, we are trying to place large flowing filaments of algae into the chambers and we discovered that there are a few complications.  There is a stir bar inside the chamber that keeps the water circulating, and we found that the algae gets caught as the bar rotates, which inhibits its purpose (see Delor’s Troubleshoot-ology blog as well for some details).  Since this discovery last week, Delor has been trying to create some sort of cage for the stir bar, so that it is able to circulate the water without interacting with the algae.  After trying several different size cages and mesh pouches, I think she has developed the perfect size to contain the stir bar and still allow water to flow!  We have tested it a few times under different conditions, and it seems to be working very well.
Nitrogen-fixing cyanobacteria under the microscope.
Photo by B. Lawrence
Using a survey of samples that we collected across all 13 streams, I have been doing my best to identify the different algal and cyanobacterial species.  Having never worked with algal species, the identification process was challenging.  When we were collecting the samples, Dr. Welter described and showed me the physical characteristics of different nitrogen-fixing species, like Nostoc, Anabaena, and Rivularia.  Having this background information was really helpful in the initial identification, but in order to more definitively classify them, I needed to look at the cells at a microscopic level.  For this, I have had the help of algal identification expert Dr. Paula Furey, a postdoctoral researcher working with Dr. Welter in her lab at St. Kate’s.  I also  studied several scientific journal articles and algal classification keys to give myself a good background and some valuable resources when looking at the species for the first time under the microscope.  Using these tools, I have positively identified nitrogen-fixers in our streams, including Nostoc, Anabaena, and Oscillatoria!!   
            We continued to venture out into the field this past week and I am also happy to report that we successfully measured nitrogen fixation rates.  We placed some of the dominant species from Stream 5 in chambers, collected gas and algal samples, and worked out the procedure for the new isotope method that we will be using in some of our nitrogen fixation surveys.  Delor ran the first set of gas samples, and we can positively say that there is indeed nitrogen fixation occurring in these streams, at what appears to be a high rate, even under the fairly common overcast conditions!! YAY!!  After looking at the samples under the microscope, I was fairly confident that we had identified nitrogen-fixers, but the gas readings have officially confirmed that they are fixing nitrogen gas from the atmosphere.  At first glance, it appears that Anabaena is fixing nitrogen at a much higher rate the Nostoc, but we need further sampling and some additional calculations to know for sure.   We plan to complete full surveys of nitrogen fixation rates in at least two more streams this week, so we will have more data to report soon! 

Sunday, July 22, 2012

Troubleshoot-ology: The Study of Problem-Solving


 Bayley with the gas chromatograph and hydrogen generator
Troubleshooting, as we have quickly learned in our time in Iceland, is a very important part of research.  It is indeed a 'search' with many challenges that require innovation and creativity, and  we are continually thinking through the best way to approach our research questions and finding that we must modify equipment, invent new designs, and rethink our plans to best suit what we see in the field.  There are a myriad of variables to constantly consider, in addition to the unexpected things that can pop up at any moment.  We began our trip with power issues with a few essential pieces of equipment - the hydrogen generator and the gas chromatograph.  Once we were able to move into a different lab, we experienced some trouble getting the gas chromatograph to communicate with a computer. But, after reading and re-reading the fine print for our software driver installation, we were able to get the technology to work for us. We also went into the field with Dr. Jim Hood, the postdoctoral research associate in charge of the field project here in Iceland, to learn the particular methods that the group has been using to make metabolism measurements. It is important that we maintain as many methodological similarities across research teams as possible so we can effectively share the data we acquire. To make metabolism measurements for isolated stream substrates, the team is using large gas-tight Plexiglas chambers that seal at the base, with a hole on the top to accommodate a dissolved oxygen (DO) probe. This will allow us to measure the amount of oxygen that is being produced or consumed as a way of evaluating net respiration and photosynthetic rates by a variety of algal and cyanobacterial assemblages found across the study streams.


Dr. Jim Hood showing off the metabolism chamber
These chambers also use a magnetic fan and a stir bar to simulate water flow within the chambers and keep the water circulating throughout the metabolism incubation (another example of creative trouble shooting). This poses a problem with some of our algal samples however, as some species we have encountered are delicate and tend to float at the top of the chamber where the stir bar is spinning.  If the algae are disturbed too much, they may behave differently than they would in the stream. They may also be broken apart, which would potentially cause them to leak out nutrients, such as nitrogen and phosphorous, which we are planning to sample and evaluate in relation to metabolic rates.  The fans may also block some light. Yet, they do a good job of mimicking flow conditions in the stream, so this may present a light versus flow trade-off in terms of replicating natural conditions, and we will have to make some decisions about the magnitude of these trade-offs and what will be most important for our measurements.  At least the chambers maintain consistent conditions across sites and even if light is reduced somewhat, the chamber design will allow for valid comparisons among streams. We are considering modifying our own gas-tight chambers in order to be gentler on the algae. This comes with its own challenges, including modifying the openings to tightly fit the DO probe. This has been an interesting process as well because the materials we are used to working with back in the United States are not always available in Iceland. This has challenged our creative process and ingenuity, and our design has evolved to suit available materials, which has greatly improved our modifications.  
             There are always many things to consider when designing experimental methods, which is not always apparent within the context of a classroom or teaching lab.  It is amazing how much effort is put into studying complex ecosystems.  Every step needs to be carefully thought out, and even when you think you have everything figured out, new insights can throw you off course.  I have come to deeply appreciate the scientists before me that have developed the techniques we use frequently in the lab, as well as the professors who design experiments that work with time and resource restraints, while keeping the science exciting. It is amazing to be a part of this process to see how important team work and collaboration really is.  When one person has a moment of defeat, another team member can come in and save the day with an innovative idea. The challenges we are experiencing show just how perseverant and tenacious scientists are, and how rewarding it is to work through the trouble spots and find exciting and creative ways to answer our research questions.  I can't wait to see it all come together, and every day we are one step closer to answering our own questions about this complex watershed. 

Sunday, July 15, 2012

All Systems Go - Gearing Up for a Big Field Week

Chambers for metabolism and nutrient uptake measurements.  
A dissolved oxygen probe records continuous changes in 
oxygen concentrations during light and dark incubation.

I am happy to report that the gas chromatograph is fully functional, the column heater is working great, and all of the instruments are operating well in their new location (new photos of our space to come soon!).  We have moved into a space in a genetics lab associated with the agricultural university here and we have met some really great people who are studying the evolutionary lineages and genetic history of wild strawberries as well as barley here in Iceland.  I know Delor in particular is excited to learn more about the molecular techniques that they are using in their work.  We were also in the field this past week, first to collect algal and cyanobacterial samples for further species identification under the microscope, which Bayley has been working on in the lab this week, and to begin our work with the sealed chambers that we will use to measure metabolic rates and nutrient uptake rates associated with different dominant algal assemblages.  We have been really lucky with the weather, but we did learn that even when it isn’t raining, it can be cold and the wind can be really strong….so strong that our equipment, including large storage containers, can blow away!  But it does have its advantages, as the wind takes the black flies with it as well, which does give you a break from the constant fluttering around your eyes, and we occasionally inhale one or two!  I don’t know about Bayley and Delor, but I will certainly tolerate these black flies over mosquitoes any day (there are no mosquitoes here in Iceland – very nice!)!   The flies aren’t so bad and if you keep moving, they do leave you alone.  We also learned that the chambers work really well for measuring metabolic rates, but they do present some challenges for working with fragile floating algal filaments and we are in creative invention mode right now, developing some new ideas and modifications that may work better for the species that we will be primarily studying.  We are gearing up for an intense field week and hope to have some nitrogen fixation rates from some of the warmer streams to report by week’s end.  Fingers crossed for good weather!  We have accomplished a great deal here and we are all excited to see our field planning come to fruition this week.

Monday, July 9, 2012

First Day in the Hengill

Hengill Power Plant - Geothermal source of energy in Iceland
As of July 6th, the instruments were almost set up and the supplies that we ordered here had arrived, allowing us to hook up our carrier gas to the gas chromatograph. The hydrogen generator has been running well, which was a relief since we were nervous about the effect travel might have on it.  We have had a difficult time getting the gas chromatograph up and running, as it seems that the oven is not warming up.  We are hoping that this will be a simple fix.   We are trying to find a better location to set up the instrument to see if we are simply not drawing enough power in our current location and whether that could be contributing to our technical issues.  So, after brainstorming and trying several problem-solving approaches, we decided to take a break from the lab and we went out to the field in the afternoon to see the Hengill watershed for the first time.  It is absolutely beautiful!  The drive to get there is a little frightening, because the watershed is located behind the Hengill Power Plant, and we must drive off-road, around a mountain to get there.  But, it made the trip all the more exciting!  The purpose of the Hengill Power Plant is to meet the increasing demand for electricity and hot water for the Icelandic people.  It is the largest geothermal plant in Iceland and the second largest in the world.  Geothermal energy originates from the heat that is retained within the Earth and can be readily harnessed in areas with high tectonic and volcanic activity, like Iceland, where this heat source is close to the surface.  It is among one of the most cost effective heating and cooling energy source available today and is roughly 25-50% more efficient than traditional (fossil fuel based) heating methods. 
Hengill watershed - our study site
Before we headed for the Hengill watershed, Wyatt Cross, the lead U.S. scientist on this project (a professor at Montana State University), said, “It will be about a 20 minute drive to the site, and then there will be one difficult spot before we get to the streams.”  We all laughed thinking, how bad can it be?  We followed Dr. Cross to the site, and along the way about every two minutes we’d say, “do you think this is the spot he was talking about?”  Well, we said that about 8 times before actually arriving at THE spot where we were driving on the side of the mountain, almost parallel to the ground because the road is not filled in!  It was a little unsettling, but we made it just fine.  Whew!!  Dr. Welter is convinced that it will be an easy fix; all we have to do is get some shovels and fill it the spot with dirt and rocks.  It’s going to take a little elbow grease, but I have a feeling we will be fixing this spot in the road before the summer is over because she did not like driving over it yesterday.  
Dr. Welter holding Nostoc
The watershed is so vast; rocky mountainsides covered with moss and tundra grasses are visible in every direction among the streams that emerge from the hill slopes. We were able to drive close to research stream one, and we walked the rest of the way to see all 17 streams.  One of the many reasons this project is taking place in Iceland is due to the natural temperature gradient among the streams within the watershed.  We measure the water temperature in each stream to see the true variation and I was the temperature taker on Thursday.  Using a digital thermometer, I placed the reading end into the water and after a few seconds the temperature would stabilize, indicating the stream’s water temperature.  Not a challenging job, but very necessary and essential to our research.  Variation in temperature plays a role in the development of certain algal species and affects their growth rate, and we saw incredible variation in the abundance and diversity of species across the streams.  Each stream we observed looked completely different, not just because of location, temperature, and size, but the variation among algal species was incredible.  Dr. Welter was identifying Nostoc, Anabaena, and many other nitrogen fixers left and right; they are all over the place!  I am going to focus a majority of my time on identification of the different species and looking for growth patterns to better explain their variation across the watershed.  Upon first glance, it seems that the warmer streams contained more nitrogen fixers than the cooler streams.  I am excited to discover which species inhabit the streams and determine what other factors could be influencing the growth rates of the cyanobacteria in this amazing place!  

Environmental Consciousness: a Way of Life


Downtown Reykjavik
From the moment we set eyes upon Iceland it was clear that the people placed a high value upon the land that they live on. Just looking at the edge of the island from the plane, there was more vegetation than pavement. As we moved in closer to the landing strip, we could see clustered cities - even these views were intertwined with ribbons of foliage. We learned quickly that the geography of the land is tightly intertwined with everyday life in all places except for the busiest streets in the heart of the city. Even the town square in Reykjavík has a large patch of grass with chairs set out to lay in the sun for public use. Every front and back yard has splashes of color from rich flower beds planted along the edge of every property line. Our own flats at the University of Iceland have miniature green roofs on lower sections of the roof. The more suburban streets have beautiful rock fences low enough to the ground to accentuate the growth of bushes and flowers that spill into neighboring yards and walkways. In the layout of the city there is careful consideration to live with nature, not to cast it aside. This reflects the cultural attitude that seems always to be mindful of overarching environmental issues.
Our building, complete with a green roof
This eco-friendly mindset was apparent as soon as we got on the plane to head overseas. We were asked to save our beverage glasses if we requested a drink refill from the flight attendants to minimize our production of waste. Here in Iceland, customers in stores are always charged for plastic bags. Even though the charge is relatively minimal, it still is enough to encourage people to bring their own bags. Every time that we are checking out at a store, the cashier asks us if we really want a bag, as if the expectation is that we will not. To my surprise, a Simpson’s comic book I found at the grocery store even discussed environmental issues in the first few frames, with a concern for recycling old electronics. Even the washing machines are much smaller than the ones that we are used to, using less water per load of clothes. We also drive by a hydrogen fueling station daily, something we would never see in the United States. It is inspiring how committed Icelandic culture is to living with a minimal impact on their ecosystem. Though it is not perfect, it shows how well working together (and responsible environmental policies and cultural practices) can change the harmful effects that people can have on the world around them. 

Immersed in Iceland

Now that we have been in Reykjavík for a week, we have had many encounters with the local people.  The culture of Iceland is unique and exciting, and the people are very welcoming and love to interact with tourists.  Nearly everyone speaks perfect English (often better than our own) and is excited to be able to practice with us. We are trying to learn Icelandic phrases and folks around town have been very patient with us, and often willing to go over the same words many times until we can say them correctly.  People’s names are especially interesting because many of them have ties to Norse mythology and majestic animals.  I have already met people named after the bear, wolf, and eagle.  The language is beautiful, but it is spoken very quickly and fluidly, which makes it difficult to pick up on.  It will take some hard work and tenacity in order to communicate effectively.
Outdoor "night" life
in Reykjavik 
When walking through town, everything is compact and efficient. The houses often have a cottage-like feel and have beautifully landscaped yards. They are very close together with a small patch of grass in the front or back used for gardening, grilling, and other outdoor activities. The people of Iceland love the sun and seem to spend every possible moment outside to soak it up before winter sets in and the days shorten.  People are always out and about, walking and biking late into the evening during the summer when the sun refuses to set.  While it is light all day and night there are few restrictions on outdoor activities and everyone seems to be taking advantage of this to the fullest. Our apartments at the University of Iceland are very close to the heart of Reykjavík, making it easy to become immersed in city life. There are many coffee shops with some of the best espresso I have ever had in my life. Even the 24 hour convenience store has coffee that surpasses what I am used to drinking (See Bayley’s blog Culture, Coffee and the 1011). At the cafés, all of the cakes that are offered have a heavenly homemade aroma and are good to the last bite. One day, there was even pecan pie offered that was made by an employee’s grandmother! It feels as though every time you enter a shop you are being invited into somebody’s house and treated like a guest of honor.
A decorative roundabout
Driving in the city was a bit of an adventure when we first got here. The roads are much narrower then we are used to, and sometimes it seems that the slightest swerve could easily bring you into a neighboring lane, or even off the road. There are also many roundabouts which took some time to get used to.  All of the roundabouts have two lanes, and we did not know for the first few days that the inner lane has the right-of-way. Frequently cars would dart in front of us, startling us every time. I am very glad we have Dr. Welter to bring us around town, as she is a little more experienced at driving than Bayley and I are. As they say, you have to be tough to live in Iceland and navigating through the city by car is no exception.
Icelandic people spare no opportunity to learn about your culture and invite you into their own, making strong ties and a comfortable environment to explore. I have never felt more welcome in a foreign place. There are very many people from all over the world, making Iceland a great central melting pot for a variety of cultures. We are able to learn a lot about the world and our place in it, opening many doors for a variety of interactions that I never thought would be possible. Before we arrived, my impression of this land was so different from what we are discovering. It seemed like Iceland would be remote and entrenched in its own way of life because all we knew was the natural, outdoorsy side of the culture and how distinct is was from the rest of the world. Icelanders hang on to their unique culture, while still finding a way to assimilate all different people into their amazing way of life. 

Culture, Coffee, and the 1011


One of many 1011's in Reykjavik
We arrived in Iceland just one week ago and have already experienced so much of the culture.  Everything is much smaller here - most of the cars are compact, the appliances look like they’ve been shrunk, the beverages are in skinnier bottles, and the coffee cups appear kid-sized.  In the U.S. everything is super-sized, as our consumer culture suggests that, “bigger is always better.” I was just unaware of how much larger everyday items are at home.   These size adjustments not only save space in the smaller living arrangements, but have an environmental impact as well.  The machines and appliances require much less power to operate, use smaller amounts of water or fuel, and the beverage containers require less raw materials to produce.    The city of Reykjavik is also very pedestrian friendly; lots of people are out riding their bikes, walking and riding scooters, which contributes to their environmental efforts.  Many of the businesses and shops in the city close around 6 or 7 pm regularly, besides the 24-hour grocery stores, the 1011 (a popular local convenience store chain), and some restaurants.  The 1011 would be comparable to a 7-11 in the United States, except it has a much fancier coffee maker.   We see one every few blocks and apparently their coffee is quite good, even from the convenience store.  I have not tried
The fabulous coffee maker at the 1011 -
best cappuccino EVER!
it because I do not drink coffee, but all of the Americans here, including Dr. Welter and Delor, say that it is exceptional.  I have no trouble believing that since the coffee machines in convenience stores and at the office seem to be fancy espresso machines.  They are quite large, but they grind the beans once you’ve made your drink selection, so it is freshly brewed for each person.  It appears that the Icelanders take their coffee quite seriously; it is a very integral part of their culture and social life.

Wednesday, July 4, 2012

We Have Arrived!

Minneapolis-St. Paul Airport - Departure
We arrived safely, although we all had some difficulty getting internet access in the first 24 hours after our arrival, so we haven’t had a chance to post new blogs about our early adventures in Iceland.  Now that we are beginning to settle in, we should be able to post more entries as there are already many stories to tell!  Travel to the airport from St. Kate’s with our 13 checked bags and containers was amazingly smooth – thanks mostly to Bayley’s family for transporting our 500+ pounds of equipment to the airport and then helping us get it to the check in counter at Iceland Air.   Thank you, thank you!   While the counter attendants were a bit surprised to see so much equipment, they were also extremely helpful and they processed our baggage in what must have been record time.  The whole process was extremely smooth and we were off to great start.  The flight was also extremely smooth and the sights were extraordinary out the window of the airplane.   The lakes in Canada were visible as well as the rugged peaks of Greenland peeking through low lying clouds – it was spectacular!  At one point, I looked out my window on the south side of the plane to see a full moon and dark star-filled sky, and then glanced over to the window on the other side of the plane to see the sun rising quickly and brightly at the very same time.  It was literally night on the south side and morning on the north as we moved northward toward Iceland.  I have never experienced anything quite like it.  Bayley was quick to learn a few Icelandic greetings from the flight attendant, including “takk”, which which means “thank you”, and so far, every time she has used it, it has been appreciated and brought forth many smiles.  Our Icelandic colleagues have encouraged us to ask questions about the language and to try to learn as best we can, although American collaborators who have now been in Iceland for a couple of years now say that it is still very difficult to learn.  But, we are trying and having great fun and everyone we have met has been very supportive!   We went grocery shopping for the first time and I stared at the wealth of dairy options in the cooler for about 20 minutes before asking a few people to help me identify coffee creamer.  Once I asked, several people shopping for dairy got involved and offered several recommendations and helped me to find what I needed.  So, it is Rjómi – but I wouldn’t have had a clue without some help!  With help from Jim Hood and Jon Benstead, both U.S. researchers working on the project here, we were able to get all of our equipment from the airport to the Veiðimálastofnun – the government lab where we are working with collaborators from the U.S. and Iceland, and to begin to get settled into our living quarters.  It was a really long first day and we were 
Keflavik Airport in Reykjavik - Arrival in Iceland with all of our stuff!
definitely feeling the effects of the jet lag and lack of familiarity with our surroundings as we tried to navigate driving in the city our first day.  We definitely got lost –I mean, really lost – but we figured it out (often with some help) and I am so proud of all that we accomplished in our first day here.  Sleep was well deserved once it came!  After some sleep, the road navigation became much easier and we are feeling like pros getting around now.  We have space at the lab where we are currently in the process of setting up our instruments and trying to make sure that everything is working properly after the trip.  We had a couple of setbacks with the gas chromatograph today, but we are hoping that we will be able to troubleshoot that tomorrow, but more updates coming on that soon!  Fingers crossed! Tomorrow, we will make our first visit to the streams in the Hengill with the research team.   We can’t wait to see the streams!!  More stories soon!