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.

Wednesday, December 30, 2015

Aquatic Ecology Lab Video

Hello Readers,
It is hard to believe that the semester is coming to a close. I have a new and exciting video production to share! In addition to a very busy semester of video production, our lab has analyzed hundreds of samples and given five presentations sharing our work.

For me, the time has come - graduation. It has been such a heartfelt honor to be a collaborator within St. Catherine University's Aquatic Ecology Lab. I am so very humbled and grateful to have been an integral part of such important ecological research and outreach efforts. I will dearly miss my colleagues and I wish all of the new members of the lab the absolute best!  Happy 2016.


Delor, Jill, Abbi, Bree, and Paula celebrating a great fall semester! 

Be sure to check out our new video - which represents the culmination of my video production efforts this semester.  Hope you enjoy and learn a little bit too!



Wednesday, October 14, 2015

Iceland Summer 2015 in 5 minutes


The Fixation on Ice crew has been back in the United States for almost two months now! Time sure flies! Sample analysis in the laboratory is in full swing, and we have been working on some video production to help visually accentuate our experience! Below is a synopsis of our summer in Iceland in just over five minutes. Take a journey to Iceland with us as we collect samples, explore the country, and have the best time of our lives! Stay tuned for further videos that will include audio from team members. 


Saturday, August 8, 2015

Birthday Bonanza

Taking in the views of the glacial lagoon on our 20th and 21st birthdays!

The undergraduates participating in Fixation on Ice 2015, Bree and Abbi, share the same birthday - July 24th! We were born 365 days apart and to celebrate, we chose to take a trip to Jökulsarlon Glacier Lagoon in southern Iceland. The drive was filled with many “oohs and ahhs,” but watching the floating ice in the glacial lagoon was the highlight of the trip.  In addition to the glacial lagoon, we saw puffins for the first time, walked along a black sand beach on the Southernmost tip of Iceland, and made a few extra stops to admire the amazing waterfalls.  It was truly a breathtaking experience - one we will never forget! It was by far the BEST birthday EVER!

Skógafoss waterfall

July has certainly lived up to our every expectation as the best month ever. Filled with lots of memories and stories to share, we couldnt have asked for a better birthday month! 

Nature’s Fireworks

This glorious photo of the sunset was taken the night of July 4th, near the harbor and downtown Reykjavik. The photo barely captures the beauty we observed with our own eyes. While we are rarely up to see midnight sun set here in Iceland during the summer, we were excited to see that nature provided us with fireworks more extravagant than anything we have ever seen before! It was quite a sight for us to see, especially since our families back in the U.S. were celebrating Independence Day. Iceland - thank you for the spectacular show!





Friday, July 31, 2015

Beyond Google


Long gone are the days of the dictionary, encyclopedia, handheld map, and textbook. When curious minds inquire, they now instead proclaim, “I will Google it”. Google happens to be one of the most widely used search engines in the world. As a highly inquisitive individual myself, I often turn to my iPhone on a daily basis to enter something into Google. After all, knowing how and where to find information is becoming a more important skill than memorization and the internet has made information more accessible than ever before.  What has really struck me about our Iceland research is that the questions we are asking are in fact “beyond Google".

Bree and Abbi preparing chambers

Now, that might sound like common sense – of course you are doing research to gain new knowledge, generate information, and maybe even create paradigm shifts. But this reality hit me like a brick. What do you mean Google no longer contains the answers to my questions about nitrogen fixation, ecological stoichiometry, or metabolic theory?! Of course much is known about these topics and previous research has guided and shaped our questions and hypotheses, but many of the answers remain in the water.

So here I am in Iceland, going “beyond Google.” Our research is in full force as we strive to understand how important biogeochemical processes drive both the structure and function of stream ecosystems. I have learned that the work we have embarked on will provide novel information and that our findings will ultimately shape thinking, teaching, policy, and ultimately add to the wide world of Google. That is all for now! Stay tuned for some exciting results that will take you beyond Google!




Sunday, July 26, 2015

One small step for ARA, one giant leap for MIMS and N15


Not a bad day to measure nitrogen fixation on stream 9
We did it! Bree, Delor, Jill and I measured nitrogen fixation rates using acetylene reduction assays (ARA), membrane inlet mass spectrometry (MIMS), and N15 assimilation in 5 streams in the Hengill Valley in Iceland this past week.  Bree has a recent blog post that describes the ARA method, so be sure to check it out.  Now, we have added two additional methods to our research.  The days flew by and I learned a lot about each method and the various steps involved. I enjoyed seeing how the methods differ, but also how each one can help us to determine how much nitrogen fixation is really occurring in these streams!  I am excited to see what the results will tell us once we process our samples. Waiting for them will be the hardest part  - even worse than enduring the black flies in the field!

Stream 11 - finished!


Our task this coming week is to  sample the channel experiment using our three methods once again to measure nitrogen fixation. We will use the same techniques and determination that we had on the natural streams, but in the channel experiment our equipment will be "mini-sized" as we will be sampling from pretty tiny artificial streams - but 30 of them! We are all rested, hydrated, and ready for any weather as we gear up for this next major sampling effort.

Sunday, July 12, 2015

Measuring Nitrogen Fixation: The Acetylene Reduction Assay

Bree and Abbi taking gas samples.
There are often multiple answers to the same question.  Whether or not those answers are parallel and agree with one another is often a different story. We are interested in determining the rate of nitrogen fixation in stream ecosystems and understanding how rates are affected by temperature. The Hengill Valley in Iceland provides us with a unique natural ecological laboratory to ask our questions, with streams that span across a 25 degree Celsius temperature gradient, while maintaining similar flow, light, and water chemistry. However, what is "the true" rate?  Getting this answer is harder than it may first appear.

Nitrogen fixation is a process completed by cyanobacteria.  While they are the only group of organisms capable of this process, they are found all over the world, in water, soil, and sometimes in association with plants (e.g., legumes). Our work in Iceland focuses on species of algae in streams that fix nitrogen. These organisms have a competitive advantage in nitrogen poor environments, including our study streams where stream water is quite nitrogen poor. They are able to take nitrogen gas, which makes up about 78% of the atmosphere, and convert it (by the use of an enzyme known as nitrogenase) to a biologically available form of nitrogen, which is an important building block for amino acids, proteins, and many cellular processes! Think of it this way: if you needed ice cream, but there was none available, you could turn to cream, sugar, and ice and make your own, if you could get the ingredients and had the right equipment to combine them. This is what cyanobacteria do in order to make proteins - they access nitrogen from the air when other sources are not available.  Evolutionarily genius!
Measuring nitrogen fixation rates on stream 11 -
 the water is super cold!

So you may be thinking, “how on Earth can you figure out how much nitrogen gas is being taken from the atmosphere and converted into the biomass of these nitrogen fixing organisms?” Do not worry - I asked the same question.  In fact, I have learned that there are currently three methods that are used to determine the rate of nitrogen fixation. We have started to answer our question with a method known as the acetylene reduction assay. Now before you panic, let me break it down. This method uses acetylene gas as a "stand in" for nitrogen gas.  Recall that nitrogen gas comprises 78% of the atmosphere.  It is typically difficult to measure the uptake of such an abundant substance. We are fortunate, however, that the nitrogenase enzyme also reacts with acetylene gas (acetylene and nitrogen gas have similar triple-bonded molecular structures), which allows us to use it to gain an indirect estimate of nitrogen fixation. 

The video below shows me preparing acetylene gas filled balloons that we insert into a gas tight chamber.  The balloon is then popped to allow the gas to be readily available to the cyanobacteria.  It is important that we shake the chamber to dissolve the acetylene gas in the water. We take gas samples before and after an incubation period of 2 hours. The gas samples are  then run on a gas chromatograph (also in video), which is used to quantify the amount of different gases in the sample. If nitrogen fixation is occurring in the chamber, the concentration of acetylene will decrease while ethylene will increase, which is the gas by-product created from our acetylene when nitrogenase is active. However, there are also two more methods that we are using to measure nitrogen fixation rates.  How will the results from those methods compare to the acetylene reduction assay?  We can't wait to find out! If you have any questions, please leave us a comment, we would love to talk more about nitrogen fixation. More methods to come next week!




Friday, June 26, 2015

24-hour mission


By: Abbi White, Bree Vculek, and Hilary Madinger            

Last night we spent the night under the Icelandic midnight sun camping at our Hengill sampling sites. It was an unbelievably beautiful night! Sunday afternoon was a rare Icelandic sunny day and the night was a continuous sunset. We were even visited by Jill and Jon who delivered pizza, falafel, and chocolate (Sirius chocolate, an Islandic treat). Perhaps our experience wasn’t quite rustic…
The mission for our trip was to try collecting diel (24 hour - hence the overnight camping) water samples to calculate net nitrogen fixation. Every hour we collected water samples, temperature, and air pressure from the stream in two different places. When we are all done sampling, the water samples will fly back to Wyoming with Hilary to be analyzed on a membrane inlet mass spectrometer (MIMS). Then we will run the data through a model to estimate  net nitrogen fixation. The basic idea of how the model works is that using the temperature and air pressure measurements we can calculate what the expected dissolved gas concentrations of the stream would be if it was in equilibrium with the atmosphere. But streams are not at equilibrium because there are biological processes changing the dissolved gas concentration. So we will compare the dissolved gas concentration in our water samples with the concentration we expect due to temperature and pressure alone and the difference in the dissolved nitrogen = net nitrogen fixation!

Since we collected hourly samples, we also had time to do a bit of exploring in the valley. We went for a midnight hike up one of the mountains, kept our feet warm with mud from a hotpot, drank water from a spring head, and embraced nature for a night. We also squeezed in some additional stream measurements to help with our analysis. Overall, we had a great time together sampling and camping and highly recommend the experience. Now we are anxious to see how the results look.

Tuesday, June 16, 2015

Your Majesty


Upon my initial arrival to the Hengill Valley stream site, I felt as if I had stepped onto another planet. The rolling hills, volcanic rock, boiling and steaming earth, and shades of green, brown, and gold graced the landscape and captivated my attention. The smoky gray fog glistened with mystery. The land is majestic. The cool, crisp, mesmerizing breeze and running water quickly snapped me out of my trance and we proceeded to prepare the experiments that will be our summer's work.



Hengill Valley, Iceland
Fieldwork has always been my favorite part of research, which is a clear indication of my love for the field of ecology. Water? Sand? Mud? Count me in! Not only is our field site one of the most beautiful places I have ever laid my eyes on, I find the unpredictable weather, the physical and mental intensity of experimental innovation, and the long days away from civilization, to be quite appealing.




Photo by Jim Hood.  Experiment where we are warming
a cold stream to 5 different temperatures, while also adding
nitrogen to some to see how the algal communities respond.
All using geothermal heat!
So far, I have spent much of my time in the field working with the team on the stream channel experiment. This has been a big job, and it has been exciting to be a part of it. I have greatly enjoyed learning some engineering, plumbing, and aquatic ecology from Dr. Jim Hood (who arrived in Iceland in early May to get this experiment up and running) from Montana State University. I am repeatedly mesmerized by the geothermal activity of the Earth, and the way we can channel that energy to experimentally vary water temperatures.


Checking out the N-fixers in one of our warm streams with
Jill and Abbi.

Back in the lab, we have been prepping for the nitrogen fixation measurement procedures and practicing our technique.  We are anxious to get our sampling underway!  Soon....

We will start that part of our work next week.

Monday, June 8, 2015

Home Away from Home

I never tire of this view from the plane window as we make our way from the Twin Cities to Iceland.  In fact, despite the late hour, I can never sleep and always have my camera at the ready, as deep night flips to bright day before my eyes.  Then, Greenland comes into view, if we are lucky enough to have clear skies.  The clouds usually break as we cross from sea to land over Greenland, but sometimes it is difficult to discern the snow covered peaks from the clouds and I have to stare long and hard out the window before I discover that yes, I can see Greenland below!  I hope to visit there someday soon and expand some our research questions to aquatic environments in Greenland.  What an amazing place it must be.


Greenland comes into view.
Iceland continues to captivate me - an amazing country, people, and place to get to  know.  I am reading the Icelandic Sagas and continue to work on my Icelandic with local friends and the scientists at the Institute of Freshwater Fisheries, but some sounds and syllables seem impossible to replicate.  I will not give up...

We have a great team here this year from St. Kate's, Montana State University, and the University of Alabama, and I am really excited to work with such an energetic and dedicated crew. We have some big experiments in front of us and  more troubleshooting to do following the long winter, but, I look forward to the greening of the landscape that is starting to emerge, as well as the explosion of cotton grass, and the upcoming results of our work.  It is going to be a great summer.  



Hengill Valley - home away from home.
We have a big week coming up that will involve lots of intensive sampling with the whole team, as well as some camping at our field site.  Unfortunately, it also looks like we may encounter a lot of rain (see the forecast link on our blog site).  But, at least we will have light!  Current day length here is over 20 hours, but it never completely darkens.  So, that will help make navigating the streams at night easier, even though we may be pretty wet!  We will report back on our progress soon.  Here's to hoping for some good weather!

Friday, June 5, 2015

Summer Coming Slowly This Year


Delor working on the sidechannel experiment.
Yes, it is sunny, but cold!
We have arrived in Iceland for the 2015 field season and summer is slowly trying to catch up with us.  It has been a long and snowy winter in Iceland and this summer is expected to be a relatively cold one. That said, we have had some wonderfully sunny days this past week.  As a result of the intense winter, many of our streams remained covered with snow and ice longer than anticipated and our experiments are running a little behind schedule.  So, this has meant that the team (primarily Jim Hood and the early crew that has helped to set up the experiments) has been constantly occupied with hard field work to get things set up and underway.  The St. Kate's crew has been scattered among the various efforts since our arrival and we don't even have a team photo to post yet, as all of us have been in different locations and out in the field on different days.  But, spirits are strong and we are having fun.  The St. Kate's team is enjoying Iceland, getting to know the Icelandic scientists and the larger team, and learning much about the work to come.  

Delor and Jim tinkering with the temperatures
in the header tanks that feed water to the channels.
Delor will be in charge of running the streamside channel experiment where we are warming a cold stream to 5 different temperatures and 6 levels of nitrogen enrichment.  As a result, she has been working with Jim Hood to get this experiment set up and to learn the ins and outs of managing the flows, temperatures, and nutrient additions so that she can troubleshoot the experiment as needed throughout the summer.  I was happy to hear from them as they returned from the field quite late last night that the experiment is now fully up and running.  This is a huge accomplishment and we are grateful to them for their amazing work on this.  So, it looks like we are now officially underway.

Tomorrow, we also start adding 15N (a heavy naturally occurring isotope of nitrogen that can be used to track the movement of nitrogen in our streams) to 4 of the streams in Hengill that span our temperature gradient.  We will sample the stream intensively over the next 5 days and continue sampling over the course of the summer to monitor the movement of our isotope through the bacteria, algae, and invertebrates. So, we are ramping up and the team is learning all of the procedures needed for the sampling.  We can feel the calm before the sampling storm.....


Bree hiking close to the channel experiment site.
While the landscape is still a bit brown and snowy,
the hot pots are steamy! 

Bree and Abbi arrived last Sunday and immediately went to the field to help with the channels.  They had a chance to do some hiking that day as well, and just yesterday they spent some time exploring Reykjavik.  They will be crucial members of the team this summer and I am excited to get our sampling underway this week.  In fact, we will be camping out at Hengill a few nights this week to collect diel samples - we will be collecting gas samples from the streams every hour for 24 hours and helping to check the 15N drips.  So, more to follow soon and we will be sure to get a few team photos!  
View of Reykjavik from the top of the Hallgrimskirkja.  

Thursday, June 4, 2015

The Summer of Firsts


Exploring the Old Harbor in Reykjavik
and taking in the views of the mountains.

Putting a final close to my sophomore year and wrapping up the short summer break I’ve been spending in Minnesota for the past two weeks, I am beginning to pack my belongings, in effort to prepare myself for the unpredictable weather in Iceland. I am eager and overwhelmingly excited to be able to join the 2015 Iceland research team. I never imagined that I would be sitting here writing about my soon to be first research experience, first international travel experience, and all of the other firsts I will be encountering in only a few days. I hope to grow not only as a biologist, but also as a student so that I can gain new skills that I can bring back to Minnesota when we are through with this summer’s research project.

This summer I will experience my first research opportunity, with the support of Dr. Jill Welter and all of the wonderful collaborators I will be joining, as we take on the challenges the Hengill region has in store for us.  This is my first chance to get hands on experience doing fieldwork and I am excited, nervous, and very unsure of what to expect. I hope to gain confidence and knowledge, so that I am able to use this in my studies at St. Catherine University and also when I am out in the field working on both my own research project and the contributing to the larger group research project as well. And, this is another “first”- I will get the opportunity to take on my own research project! I will be studying ecological stoichiometry. I am still piecing together the details of my project, but it is coming along!

Waiting to get picked up at Reykjavik
Excursions to join the research team!


This summer I will also have my first international travel experience outside of the United States. In preparation for the trip, I applied for my first passport and my first stamp will be from Iceland! This summer I will learn to adapt very quickly to a new style of living along with the weather, people, environment, and attempt to sleep in the land of the midnight sun.  I am so excited for this opportunity, which will allow me to experience a part of the world that I would otherwise not have had a chance to visit. Since I know I will have so many more first experiences in Iceland, I look forward to sharing my collection of firsts when we arrive in the beautiful country! Wish us luck as we embark on a thrilling and intense summer of research, laughter, hard work, fun, and adventure!

Friday, May 15, 2015

Transition, Translation, and Transformation

Transition:
            The academic regimen is composed of transitions: from major to major, class to class, topic to topic, and in my case, from lakes to streams. I was introduced to the Welter lab in the summer of 2014 on a Minnesota lake project. After a lovely summer in the field, we have analyzed exciting and novel results! I thoroughly enjoyed the research process from designing a project, working hard long days in the field, all the way to the analysis of results! 
            I am continuing this process as a new collaborator with the work in Iceland. This opportunity will allow me to engage on a professional level and experience the entirety of the scientific process. I have fallen in love with the highs and lows of the research experience and am eager to continue to collect data and answer globally important questions. I have transitioned into preparatory work for our summer 2015 research in Icelandic streams. The transition has been smooth, as both of my aquatic ecology research projects have some parallels in methodology and nutrient cycling dynamics, but strike contrast in flow velocity. This exciting new challenge adds a twist to my familiarity of the low flow associated with lakes. In my transition to streams, I have researched, proposed and developed a project, which includes looking at how metabolism and nitrogen fixation of both nitrogen fixing and non-nitrogen fixing organisms vary over a temperature gradient. I am excited to continue learning, and growing as a research scientist! 

Translation:

Icelandic proverb: Af gódu upphafi vonast góður endir.

English translation: A good beginning makes a good ending.

Drilling holes in incubation chambers
            Dr. Jill Welter and I are currently funded through St. Catherine University’s Assistantship Mentoring Program. With this funding I have had a jumpstart on writing my proposal, learning laboratory procedures, and constructing field supplies necessary for the Iceland stream project. I am so appreciative and grateful for the time and effort I have been able to put forth towards this research endeavor.
            Like the process of translation, the comprehension and understanding of such a rigorous and intense project takes time, hard work, and patience. This academic semester I have gained confidence in reading and analyzing scientific literature pertaining to stream ecology, familiarity to essential laboratory techniques, and project methodology and logistics. The research preparatory process has been vital in my comprehensive and quantitative reasoning skills that will be useful in the data collection and sample analysis days to come. It has been a good beginning, and I am excited to flow through this journey into the world of stream ecology.

Transformation:

Nine bins and counting...
Iceland provides a unique, natural, ecological laboratory useful to research the effects of increased stream temperature on biological processes and species composition. The Iceland stream project has been, and continues to be transformative in ecological science. With an increase in average global temperature at the forefront of ecological concern, this project will broaden our knowledge on how temperature change may affect biological processes in a variety of ecosystems. Not only is this work transforming the field of ecosystem ecology, but that of my undergraduate research experience. Already, I have been transformed. I have gained the assurance to take initiative and to formulate and question ideas central to the field of freshwater aquatic ecology. I am greatly looking forward to witnessing all that Iceland has to offer, and the adventures and transformations to come! Our bins are packed, our flights are booked, and we are ready for research - hopefully Iceland is ready for us!