In the Dark

    For the past week we have been trying to get our final samples of the summer season here in the Dry Valleys. Our last sampling expeditions have been delayed by weather so the last few days have been all in the lab looking to finish up anything we can.

    Photosynthesis extraction
    Photosynthesis extraction.

    The team has been lightheartedly talking about this part of the data collection for weeks - with a certain ominous subtext. You see, we have taken hundreds of samples this season. We extracted the organisms and identified and counted along the way. Everyone on the team chipped in to get the task done accurately and efficiently. All of this time consuming work has been spread out over time.

    In the geo-chem lab, Meredith and Sarah have been taking every one of those samples and completing the chemical tests which tell us the pH, conductivity, and moisture content of the soils. They have spent many late nights running extracts from soils that are going to be packed up and shipped to their university for analysis of nitrogen, salts, organic and inorganic carbon, and metallic ions.

    But one test has to be run on a tight, uninterrupted schedule. That means, once we have all the samples, we can start. Along with the complex steps and time sensitive nature, it also has to be done in a light-free environment - aka - the dark.

    In most ecosystems, the energy for a food web starts with light from the sun. This light is captured through photosynthesis and used by producers like alga, bryophytes (mosses), and cyanobacteria to make food. These organisms take carbon dioxide from the air and combine it with water and light energy to make molecules that store energy. This is thought to be the source for the carbon that is then used by other organisms to live and grow.

    Meredith walks us through the steps of chlorophyll extraction
    Meredith walks us through the steps of chlorophyll extraction.

    The measurements we are running will tell us how much chlorophyll is in a specific amount of soil. In forests and grasslands this would be insignificant compared to the plants growing above the soil, but in this ecosystem, soil is where the producers live. By measuring the amount of chlorophyll in a soil sample, we can estimate the amount of energy and carbon that is brought into the soil food web through photosynthesis.

    Sarah measuring chlorophyll using a spectrophotometer
    Sarah measuring chlorophyll using a spectrophotometer.

    One of the biggest questions in the Dry Valley ecosystems is where does the carbon come from. Many studies have investigated the question of where different nutrients come from (or are not coming from). There are lots of gaps in our understanding of how different nutrients move through ecosystems. There is much interest in carbon because it is the building block of all life on earth. It is also a crucial component to greenhouse gasses that control the temperature of Earth itself.

    We will never understand every aspect of our ecosystems but our knowledge is cumulative. Each time a new discovery is made here or new understanding is developed from the research, many new questions crop up. These new questions drive the next generation of research. If we can understand how carbon moves through ecosystems better, we can make better models of how the planet functions. Better models shed more light on understanding climate, climate change, and ways to address it. Lots of questions remain for future scientists. As you can tell from the dynamics of our team, there are many young scientists taking up the challenges.

    No Groundhogs to tell us the weather

    It's Groundhog Day eve in the US as I write this. On Groundhog Day we use the signs of nature to make predictions about the changing of seasons. I wonder what change people would note here in the Dry Valleys. One thing we are all noticing is more cloudy days and a sun much lower on the horizon. Maybe, once we understand the Antarctic nematodes better, they too can have a day celebrating their weather predicting abilities...

    Author
    Date
    Location
    McMurdo Station, Antarctica
    Weather Summary
    Cloudy, light snow
    Temperature
    -7°C|19°F
    Wind Speed
    E @ 7
    Wind Chill
    -13°C|9°F

    Comments

    Kaci Kime

    Hey Mr.Henske,
    How long does it take for the test results to come back? Seeing that you took 100 samples it seemed like it took a while.

    Bill Henske

    Hi Kaci-
    Thats a good question. It's hard to time how long it takes to analyze everything about one sample. For each we have to collect 18 different measurements. There are 7 of us working on it and we take turns doing different things. Some parts have to be done all together in batches. Some have to be done right away, some are going to be done in Virginia later this year. Just analyzing one samples animals can take 45 minutes- thats after weighing and extracting. I would estimate about 2.5 human work hours per sample total for all of the measurements. Thats a good thing to think about when trying to decide to take an extra sample or not.

    Parker Woodruff

    Hope your having fun!

    Bill Henske

    Thanks Parker. It is a lot of fun. I do miss plants, animals, and night time.

    Christina Esbeck

    Hello, Mr. Henske
    This is Christina it must be hard working in the dark. Also, I wonder if they would be able to have groundhogs survive in Antarctica long enough to predict the weather. The samples seem cool. I hope you are having a good time in Antarctica. We are looking forward to having you back here though. Also, I got your post card and this is the first stamp I have from Antarctica. Also like you said I am looking at your journal.(:

    Bill Henske

    Hi Christina- It doesn't seem hard to work in the dark until you have to write down all the data in BLACK INK :) We can have a little light, but the less we have, the more accurate our results. A groundhog could possibly live here in the summer if it was being fed but it sure wouldn't be happy. It could not survive the winter at all. Its burrow would just go into the permafrost and the groundhog would freeze solid. Even though they can survive low body temperatures, they can't survive freezing. I look forward to seeing you all soon!

    connor kalagian

    Hello
    what is the coldest it had been there, and have you tried to clime a mountain?

    Bill Henske

    Hi Connor- It's been in the 10s and 20s most days here. What makes it feel really cold is the katabatic winds- the cold winds that flow down from the polar plateau into the valley. Sometimes these winds are 50 or more miles per hour which can suck the hear right out of you. Thats why we always have to have our ECW with us at all times in the field. I havn't climbed a mountain but I have climbed a volcano. There is a "small" cinder cone volcano in McMurdo that over looks the base. We don't spend any time on the tops of mountains because they are the least likely to have soil/ soil organisms. We did do a cool hike up on a glacier but mountaineering requires special gear and training (and more time than we have)

    Gracie Hardesty

    Hi Mr. Henske, does what you do every day vary, or is it mostly running different tests on the same or a few things?

    Bill Henske

    Hi Gracie-
    It changes a lot - we have a big calendar of all the experiments we are running and how long it will take and how we are going to get there. Right now we are finished with all of our samples but need to go out to the Dry Valleys to repair and replace some equipment. Thats one of the best things is that we get to do lots of different things. We have a mix of time in the field and time in the lab. Unlike scientist in country, we don't have any days off. If you are doing work on Antarctic things you have to do as much work as you can while you are able to be here - so the scientists and students try to cram in as much as possible so when they are back home they have all the data and all the samples they will need to finish their work. They can't redo anything or collect any more data for another year- if ever- so a lot of planing goes in to using the time.
    Unfortunately there are things that get in the way- like weather. We have been waiting 3 days for the weather to clear enough to get to our last site of the season. It looks like today we might get there!

    Emma Loos

    How much have you realized that you miss certain things since being there? Also, did you adapt quickly to the light there or did it take a while?

    Bill Henske

    Hi Emma- I adapted to the light right away and I felt really productive with all the daylight but I think it is starting to wear me out. At first I would just sleep with a hat over my eyes. When you are in town, the dorms have these blackout shades that make the rooms really dark to help people sleep. Most people arent getting enough sleep I would say. The main things I miss are friends/family /students, plants and dogs. I didnt miss the internet (after a while) and I dont miss driving everywhere