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After getting the lab all set up and prepared to run our soil samples, the whole group set off for our first trip out to the Dry Valleys. We split up and boarded two different helicopters- this is the first group heading out to cross the McMurdo Sound into Taylor Valley.
Our first sight from the air is our home away from home, McMurdo Station. Everything we need is located here, from our lab, dorms and cafeteria, to exercise gyms and libraries. It feels sort of like a very small college town, but looks very different.
We fly across the Ross Ice Shelf in helicopters in order to reach our study site, the McMurdo Dry Valleys. The distance traveled averages around 50 miles and takes approximately 40 minutes. We wear protective helmets, and of course always wear our seat belts! Below is Nick, happy to be on his first helicopter ride.
Our flight takes us over frozen McMurdo Sound and the largest sea ice shelf in Antarctica, the Ross ice shelf. Below, you can see that the mountains rise directly from the icy ocean. Why are the mountains only partially snow covered, even though Antarctica is so cold?
Cracks in the sea ice begin to develop as the water and ice are heated by the relatively warm rays of the summer sun. You can see a few of these cracks below as we approach the continent.
Soon enough, we enter Taylor Valley and immediately white ice gives way to rocky soil. These ecosystems are the coldest and driest on Earth, and no higher plants are capable of surviving here. The picture below reveals the stark Dry Valley landscape.
We touch down on the helicopter or “helo” pad and unload our gear for the day’s fieldwork, which includes our backpacks, soil sampling equipment, personal items such as food and also survival bags which include emergency supplies should be become detained in the field. Then, the helo departs and we go about our experiments until they return to transport us to McMurdo.
Upon our arrival on the south side of Lake Hoare, our leader, Dr. Diana Wall, gave us an introduction to the various long term experiments that have been going on in this area. Dr. Wall (below, at left) has been studying soil ecology in the Dry Valleys for decades, as this year marks her 19th season on the Ice. Her dedication and scientific achievement have been acknowledged by the naming of a Dry Valley in her honor!
After some planning, we broke up into groups in order to take soil samples and apply experimental treatments to certain plots of soil. Below are soil warming chambers that are part of an investigation into the biotic effects of increased soil temperature, water and carbon addition. Why would we choose these particular treatments and be interested in their effects on soil biota (living things in the soil)?
The Dry Valley soil ecosystems are extremely fragile, and great care must be taken when we are in the field. We walk single file on established paths so that we minimize our effects on the belowground communities. Here, our team travels down a Taylor Valley trail.
As we walk around, we notice that the scale here is quite astonishing and humbling. We humans seem so small compared to the daunting mountains and glaciers. It is fascinating that microscopic nematodes are capable of thriving in such a place!
In order to evaluate the effects of climate change on soil biota, long term monitoring projects are in place that track the nematode abundance and distribution from year to year. The picture below shows four members of our team taking soil samples from one of these long term experimental sites. Lake Hoare and Canada Glacier are in the background.
When our fieldwork is done for the day, the helicopters arrive again and we are treated to more spectacular views on the return trip. Here you can see an iceberg in the distance, one of many that we flew past on our way back to McMurdo. What a day!