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From the time we arrive in Antarctica to the time we depart, we hurry around working to obtain our samples, get them processed, collect good data, and get the samples prepared for shipping home. Then it’s packing, cleaning, and rushing to get on a plane. The whole month is a whirlwind of science. It’s a blast, but it’s also exhausting.

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The C507 Soil Team in front of the Crary Lab. From left to right: Jessica Trout-Haney (Dartmouth), Dan Bransford (Virginia Tech), Summer Xue (Brigham Young), Tandra Fraser (Colorado State), Diana Wall (Colorado State), Walter Andriuzzi (Colorado State), Ashley Shaw (Colorado State), Jeb Barrett (Virginia Tech), Ruth Heindel (Dartmouth), and Byron Adams (Brigham Young).

I’ll give you the overview of what we did this season: In summary, we sampled five core studies at six different sites, applied treatments to two core studies at three sites, completed lab work on 420 soil samples, serviced meteorological stations, collected samples from aeolian (wind-blown) sediment collectors, and collected additional soil samples from multiple locations for our work in labs back home. Mixed in with this work are repairs to equipment, weather delays, establishing proper communications at field sites, and ensuring work is done in a safe way that preserves the Antarctic environment.

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Diana Wall takes a soil sample near Marr Pond in Taylor Valley. Photo by: Ashley Shaw

The first priority for work is sampling core studies, which are critical to the NSF Long Term Ecological Research program’s mission. So, on nine different trips (both overnight and day trips), we went to the McMurdo Dry Valleys via helicopter to sample our core experiments and long-term study sites. These included the Stoichiometry Experiment, the P3, the Elevational Transects (read about these here or here), the LTM, and the controls from the BEE plots. We bring these soil samples (each one weighs about 500 grams) back to the lab for processing (you can read about our soil extraction process here). Once the nematodes and other critters have been extracted, we use a microscope to help us identify and count every individual animal from each sample. Not only do we study which species are present, but also details about their life history, including their sex and whether they are alive or dead. This gives us information about community trends. At the same time, we are performing soil chemistry measurements to evaluate soil carbon, pH, salinity, phosphorus, and nitrogen. These chemistry data help to indicate which environmental conditions are most (or least!) suitable for life. We also extract and measure chlorophyll-a as a proxy for primary productivity.

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Jess weighing soil for soil chemistry analyses. Photo by: Ruth Heindel

Besides sampling these experiments, we also have to apply treatments to some of the core experiments. This year, we applied treatments to the P3 and the Stoichiometry Experiment. The P3 treatment took place over a couple days, and required Byron, Jeb, and Dan to stay at F6 camp and walk to the experimental plots. You can read about the treatments (here), but in short, this treatment involves pumping water up from Many Glaciers Pond, sterilizing the water, and pumping the water down slope at the subsurface to simulate melt flowing over the permafrost. The Stoichiometry Experiment requires nutrient treatments to be prepared in the lab (you can read about that here), this then requires hauling ~30 carboys filled with nutrient solutions (about 5.6 liters in each carboy) out to our experimental plots and applying those solutions.

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Byron carries carboys full of nutrient solutions to the Stoichiometry Experiment plots in Taylor Valley. F6 camp in the background at right. Photo by: Walter Andriuzzi

We went out on a few more day trips to put in new batteries and check on our meterological stations, take samples from and repair aeolian sediment collectors, and to collect some more samples to take back to our labs at home (for individual projects such as PhD or Masters projects).

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Summer and Byron are happy that the meteorological station in Miers Valley is now fixed and working! Photo by: Ashley Shaw

We are happy scientists –we had great weather with very few delays, our samples are ready to ship home, and all of the data has been collected for this season.

Mission complete!

Written by: Ashley Shaw

Many researchers working in Antarctica study large things. The ice lakes and glaciers are so massive that the glaciologists who study them may find it easier to use airplanes rather than tons as unit of measure. Oceanographers and climatologists track down icebergs larger than some countries. Volcanologists are checking the vital signs of that formidable giant that is Mount Erebus (3794 m above sea level, more than 12 thousand feet). Astronomers look out of the clear Antarctic skies to stars and galaxies.

Many biologists study large and easily recognized creatures such as seals, penguins, and whales. But where we “Wormherders” are conducting research there are no living things that the naked eye can see. We are focusing on much smaller creatures, such as nematode worms. Virtually all soils on Earth host nematodes, but in the Dry Valleys very few species occur, and they are specially adapted to this extreme environment. The same goes for the microscopic algae and the bacteria living in lakes and soils that other teams in McMurdo are studying. Some of the most exciting ecological questions in Antarctica are about very small things indeed.

(Admittedly, even nematodes and microbes may be described as very large by the particle physicists working on “AMANDA”, the Antarctic Muon and Neutrino Detecting Array. There truly is science for all sizes at McMurdo.)

The McMurdo Dry Valleys seem as desolate and lifeless a place as one could conceive. But take a scoop of soil from almost anywhere in the valleys, subject it to an appropriate extraction process, put the resulting water solution under a microscope, and there you go: living creatures, more abundant and active than you might suspect.

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Scottnema lindsayae, one of the most abundant residents of the McMurdo Dry Valleys. A female and a male caught in the act of mating. Photo by Jessica Trout-Haney

Some of us have been busy all day identifying and counting specimens from samples we collected last week. It’s not at all boring as some might suspect, partly because of the beauty of the organisms we look at. Nematodes bend, coil and stretch elegantly on the microscope plate. Scottnema lindsayae, the most abundant, performs what may look like some contemporary dance. Less common but hard to miss, the much larger Eudorylaimus antarcticus flexes slowly, like a microscopic python waking from sleep. A Plectus sp. with its head inside a dead rotifer, busy scavenging on bacteria inside the decomposing body, looks like it has put on a mask to scare the others around it.

Nematodes dominate this playground, but there is more. Rotifers scurry, hop and cartwheel across the plate like pesky children, sometimes playing tug-of-war with nematodes over lumps of organic matter. Even faster than rotifers, a ciliate slides effortlessly, in shape and motion somewhat similar to a flying saucer (or a swimming saucer). Tardigrades move clumsily on their short legs, but don’t be fooled by their cute appearance – they are some of the toughest creatures on Earth.

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Some team members load scientific equipment and supplies on the helicopter that will take them from Lake Hoare Camp to another location in the Dry Valleys. Photo by Walter Andriuzzi

It was not an easy job to collect these biological samples. The helicopter is the only means on transport to get from McMurdo to the Dry Valleys. Flights have to be planned days in advance with the crew, but often they need to be rescheduled due to the unpredictable weather. Once in the Valleys, the Wormherders have to move fast to finish sampling before the helicopter returns (but it also helps against freezing).

Sometimes daily trips aren’t enough. Thankfully for us, there are a handful of well-equipped camping sites in the Dry Valleys. Last week we spent a night at Lake Hoare Camp, managed by Rae Spain and Renee Noffke – a homely, warm place in a land of ice giants and sharp winds. The landscape around the camp is so spectacular that some of our team, despite being quite tired from the day’s work, couldn’t resist the temptation of an after-dinner hike. We walked along Canada Glacier, past mummified seals and ice stalactites, and on to the moraine on the side of the glacier, and eventually we stepped on the glacier (with the appropriate footwear!).

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Lake Hoare Camp, an important logistics base for researchers working in the McMurdo Dry Valleys. Photo by Walter Andriuzzi

There might seem to be a paradox – on one hand the size and majesty of the Dry Valleys, and on the other hand the minuscule beauty of the fauna that inhabits those soils. But such is the greatness of ecology, a science that connects the small and the large, the hidden and the obvious. With a bit of assistance from the weather, we’ll be collecting more samples from the Dry Valleys in the next few days, and who knows what surprises we might find under a microscope. In the meantime, some team members are camping near Lake Fryxell in Taylor Valley, taking care of one of the most exciting ecological experiments undergoing in Antarctica.

by Walter Andriuzzi

Hurray!!! We made it to the field yesterday! We are very happy scientists!

In the helicopter on the way to F6, we passed over the icebreaker, USCGC Polar Star. This ship is cutting a channel for the resupply vessel to reach McMurdo Station in a few weeks. It’s amazing that the ship can break through several meters of sea ice! Also, if you look closely, you can see one of our stoichiometry treatment carboys (lower right corner) safely tucked away in the helicopter. Photo: Ashley Shaw

In the helicopter on the way to F6, we passed over the icebreaker, USCGC Polar Star. This ship is cutting a channel for the resupply vessel to reach McMurdo Station in a few weeks. It’s amazing that the ship can break through several meters of sea ice! Also, you can see one of our stoichiometry treatment carboys (lower right corner) safely tucked away in the helicopter. Photo: Ashley Shaw

Yesterday, Tandra, Andy, Matt, and Ashley went to F6 near Lake Fryxell to apply treatments to the stoichiometry experiment. It took us a little over two hours to complete our mission. First, we carried the full carboys from the helo pad to the plots. And at 25lbs per carboy, they get heavy! After setting up all of our supplies near our experiment plots, we carefully filled the pouring containers with the correct nutrient treatment. Then, we slowly applied the nutrient solutions to the correct treatment plots. After each one has been poured out onto the correct plot, the pouring container has to be refilled and poured out again on the next plot! We do this 8 times for each treatment (48 times!), because each of the 6 treatments that requires pouring has 8 replicates.

At the stoichiometry plots at F6 yesterday. Matt (L) is happy that we’re out in the field and getting some work done. Andy (R) prepares supplies for the treatments. If you look closely, you can see the plots that have already been treated (they’re wet!) and the stakes that mark the plots. Photo: Ashley Shaw

At the stoichiometry plots at F6 yesterday. Matt (L) is happy that we’re out in the field and getting some work done. Andy (R) prepares supplies for the treatments. If you look closely, you can see the plots that have already been treated (they’re wet!) and the stakes that mark the plots. Photo: Ashley Shaw

Today, Byron, Zach, and one of our Italian colleagues are on standby to visit New Harbor at the mouth of Taylor Valley for an algae and moss project. Tomorrow, Ashley, Andy, Matt, and Tandra are heading to South side Lake Bonney to treat the second set of stoichiometry plots and to sample the BEE control plots (read about that experiment here).

We got some help from the Artist-in-residence, Lily (far-right). She and Matt (right-center) are filling the containers. Tandra (left) heads out with a full pouring container to treat one of the plots, Andy (left-center) waits for the next pouring container. Photo: Ashley Shaw

We got some help from the Artist-in-residence, Lily (far-right). She and Matt (right-center) are filling the containers. Tandra (left) heads out with a full pouring container to treat one of the plots, Andy (left-center) waits for the next pouring container. Photo: Ashley Shaw

 

Written by: Ashley Shaw

The weather was better yesterday, but we still did not get out of McMurdo Station due to the backlog of helo flights from Friday and over the weekend. We are on the helicopter manifest for today, but now it’s snowing, windy, and there’s low visibility. If some nicer weather returns this afternoon, we may still get to the field today.

View from the helicopter while flying into F6. Photo: Ashley Shaw

View from the helicopter while flying into F6. Photo: Ashley Shaw

Later today (or maybe tomorrow), we will be going to the F6 site near Lake Fryxell to treat the stoichiometry experiment. The stoichiometry experiment was designed to help understand which elements are the most limiting to Antarctic soil communities. Additionally, this experiment looks at how landscape history (both Nitrogen deposition and Phosphorus weathering) affects the response of soil organisms to nutrient additions. We have two contrasting sites: Fryxell lake basin and Bonney lake basin. At the Fryxell site (that will be treated today), soils have high native Phosphorus content, but low Carbon and Nitrogen. Contrastingly, the Bonney site soils have high native Nitrogen content, but low Carbon and Phosphorus. We plan to go to Bonney for treatment in a few days.

Treatments are:

  1. Control – nothing added
  2. Control – water added
  3. Nitrogen added
  4. Phosphorus added
  5. Carbon added
  6. Carbon and Nitrogen added
  7. Carbon and Phosphorus added

First we prepared all of the treatments described above in the lab. This consists of filling carboys with water plus the nutrient that needs to be added. We take these out to the field with us and add these solutions to the treatment plots.

Prepared stoichiometry treatments line the hallway of the Crary Lab waiting to be deployed to the field. Photo: Ashley Shaw

Prepared stoichiometry treatments line the hallway of the Crary Lab waiting to be deployed to the field. Photo: Ashley Shaw

Next week, some people from our group will head back out to Fryxell and Bonney to measure soil respiration, or the amount of CO2 coming out of the soils. This gives us an idea of the level of biological activity in the soil and the treatment effects on this biological activity.

Written by: Ashley Shaw

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