Tuesday, March 26, 2024

Back in Punta Arenas

We made it back to Punta Arenas yesterday! Luckily the weather was nice, and the plane could fly on schedule. We have enjoyed a comfortable bed with a nice shower and, best of all, fresh food!

As you can see, that is much fresher (and greener) than the typical Escudero meal!

Today we are sorting the samples and cargo to make sure they are properly stored and ready to ship back to the United States. We are starting at the INACH lab where they were stored overnight. 

Luckily, it is “safety first!” at the INACH lab!

Next, we will take it all to the U.S. warehouses where it will be processed for shipping home. We are almost done with our work!

Sunday, March 24, 2024

Packing

We have been busy packing up all of our samples. They require all of our cargo the day before our flight back to Chile is scheduled. That’s been tricky because we were still processing the last of our samples! But, we have a managed to get it all done. Now, the only thing left to do is all of the paperwork for the shipments!

Most of our time at Escudero is spent in this main building where the labs, dining area, and meeting rooms are. It is painted to celebrate many of the themes of Antarctic research conducted here. (But, it does not feature any soil organisms! What an oversight) The flag mast in front of the building always flies the Chilean flag at the top, and then flags from all other countries who are represented here. You can see the American flag on the left in honor of Hannah and me. We also have a Brazilian, an Ecuadorian, and Colombians here. It is an international group!

Now, we can relax a bit while we wait for our fight tomorrow… fingers crossed the weather cooperates!

Saturday, March 23, 2024

Wrapping up the science

Today was our last day of field work. (We are scheduled to leave Escudero on Monday!)

Our main task was to take down an experiment we set up soon after our arrival. One of our questions is how moss influences the soil to provide a habitat for organisms. A main way moss can have that influence is by insulating the soil and protecting it from the harsh temperature fluctuations. Zoie, who was with us last year, wanted to measure that! She sent us with equipment to set up an experiment for her.

We set up an experiment where we ran thin wires that measure temperature (called thermocouples) into different parts of the moss. We had thermocouples at the top of the moss (the canopy), at the point where the moss and soil meet, and then an inch into the soil below the moss. That way we can measure whether the temperature changes differently across that small area of a moss tuft. We also put thermocouples into bare soil to see whether the temperature fluctuates differently under moss compared to without the moss coverage.

Those thermocouples are attached to a device that recorded temperature from each thermocouple every 5 minutes for a week. This is what they looked like when we installed them. If you zoom in, you can see the wires coming out of the box and into the moss.

We left them out for a week, but it has been very cold and and snowing a lot. So this is what the site looked like when we came back this morning:

So the wires going into the moss were now covered with snow!


We dug them out. When Zoie looks at the recorded temperature data, she will have an answer to the question!

Friday, March 22, 2024

Feliz cumpleaƱos, Angelica

Today is Angelica's birthday! 

Last night, we decorated the dining room so that she would wake up to a festive birthday celebration. In Antarctica, you can't just pop out to the store to buy decorations, so we had to make them from whatever we could find around the station. We made balloons from lab gloves, streamers from labeling tape, paper flowers from Kimwipes, and a birthday banner from absorbent pads! It was a group effort. We had to work hard to keep her from coming in to ruin the surprise!

This morning, we were greeted by a beautiful birthday sunrise over Fildes Bay!

The cooks made a beautiful birthday cake that we all got to enjoy. It's amazing what they can do with the meager ingredients we have down here!

So far, Angelica is having a great birthday. And, we all got to eat cake for breakfast!





Thursday, March 21, 2024

Hannah's Best Day of Science, Ever

Yesterday was a banner day for Hannah!

First, she had the TRUE Antarctic field work experience! We were able to go back to Carlini to finish our transect from a few days ago. But... it was snowing the entire time!

First we find the moss, and then we count the species that are living there!

It is difficult to be a soil scientist when there's snow on the ground. We had to search for our plant and soil samples beneath the snow, all while getting snow blown in our faces! It was wet and cold, but we managed to complete all of the work! Success!

Dr. Becky and Hannah sampling under the snow.

After we completed our sampling, the Argentinians at the base were very kind and fed us a warm lunch. They even gave us each a super cool Base Carlini sticker! That was the first super fun extra thing to happen that day. Stickers are very popular in Antarctica, because they are a great, lightweight souvenir to trade with people. I gave Arizona stickers to the people at Carlini who helped us, and we received Carlini stickers!

On the boat ride home, we got to witness something special close-up. A large part of the glacier fell off into the bay. This is referred to as the glacier "calving", and it's how many icebergs are born. This is a regular occurrence in the mid and late summer, because as the temperatures warm during the season, the ice on the edge of the glacier starts to melt and crack. That makes the edges unstable and they start to break off. (The problem, of course, arises when the summers are warmer than they naturally would be, so you get more calving than would naturally happen. That's how we see the overall amount of ice decrease on the continent.) At first, we only saw small bits of ice roll out of the cave in the glacier. Then, suddenly, this happened:

That was very exciting, including the rapid retreat away from the big wave that was coming from the splash! At this point, the weather was better than the snowy morning of work, and we had a scenic journey back to Escudero. And, finally, as we were pulling into the dock at Escudero, who should come visit the boat but a leopard seal!

Leopard seals are one of several species of seal that live here, but they are the only species known to attack humans. They don't particularly want to hunt humans... really it's just that they have mistaken human divers for seals. The wet suit and flippers can make a human look an awful lot like a smaller seal that the leopard seals would normally prey on. They also eat penguins and other marine animals. Because their only predator is the orca, they are not generally afraid of anything on land and will follow boats with curiosity, occasionally sticking their head up above water to see what's going on. This one came right up to the boat to say "hi" to Hannah!

So, a couple of cool sightings, some rugged field work, and a new sticker. A good day! Today we have been busy in the lab processing the samples that we collected yesterday. And it's still snowing!

Monday, March 18, 2024

Revisiting Nelson

Today we went back to Nelson Island, which is "next door" to the island we're currently on.

Base Escudero is on King George Island off of the coast of the Antarctic Peninsula. It is a large island in a chain referred to as the South Shetland Islands. Nelson Island is the smaller one to the south of us. 

You can see in the map of King George Island that it is mostly covered by a large glacier. We are down in the red box. This part of King George Island is called Fildes Peninsula. You can see that there are many research stations on Fildes Peninsula, including Escudero where we are based.  (You can also see the peninsula to the east marked for Jubany Station. That is the old name of Base Carlini, where we were doing our transect in my previous post.) Just across the water at the bottom left corner of the map is Nelson Island, where we were today. It also has a glacier coving much of the island.

Last year, we sampled a successional transect from near the edge of Nelson's glacier towards the northern tip of the peninsula where the ecosystem is more developed. This year, we returned to collect some extra moss samples that will allow us to collect extra data about moss physiology. That way, we can understand how the moss functions as it develops from its young pioneer stages in early succession sites versus when it is more mature and developed during late succession. 


But why do we care so much about moss, specifically? Moss is the most abundant vegetation on the continent of Antarctica. There is a lot of it in the northern part of the Antarctic Peninsula, which has the slightly more hospitable climate and water is more available. In the desert regions of Antarctica, moss is only sparsely growing in some locations. But here in the South Shetland Islands and other nearby areas, we see quite a lot of it! This is the equivalent of our "tree canopy" like you'd see in a forest in the United States or Europe. 

Antarctica doesn't have woody plants. In fact, the only vascular plants are one species of grass and one species of pearlwort. Other than that... it's moss, algae, and lichens! So the reason we are so interested in moss is because of its major role as the main vegetation in Antarctica. The photosynthesis, and therefore CO2 uptake into the ecosystem is largely done by moss. The moss then becomes a food source at the bottom of the food web, and its decomposition recycles the carbon and nutrients that the moss takes up. The moss can help insulate the ground, retain water, and reflect light to protect the organisms that use it as a habitat. It can survive desiccation and wake up as soon as water is available again! It is an amazing plant! We will measure how the various species of moss differ in these physiological properties, how they help develop the soil during succession, and how that influences the organisms that live there. 

Sunday, March 17, 2024

Succession gradients

 We've spent the past couple of days working on samples from a new field site. One of our main goals for this project is to measure plant and soil properties along a gradient of ecological succession from a receding glacier. Over the past two years of this project, we have measured transects from two different locations. Yesterday, we collected samples from a third transect.

To get to this new field site, which is a ways across the bay on another peninsula, we ride in boats. The presence of the glacier makes it impossible to walk across land to get to the peninsula, so we have to go by water! It is of course deadly if we fall out of the boat into the freezing Antarctic water, so to be extra safe, we have to wear big puffy suits and a lot of safety gear whenever we ride in boats. These big puffy full-body immersion suits provide both flotation and the ability to keep us alive in 5°C water for 1 hr. With the addition of big boots and water proof gloves, we are ready to go!

We traveled across Fildes Bay to another peninsula where one of the Argentinian bases is located, called Base Carlini. After some warm hospitality from the residents of the station, we hiked up into the moraines to find an early-succession site with only early pioneers of moss coverage. As you can see, it's not highly vegetated. There is moss and lichen on the ground, but it's fairly sparse... and partially covered by snow!

Dr. Angelica and Hannah measuring plant cover with cold hands!

Angelica and Hannah measured the resident plant community coverage while I sampled the moss and soil underneath it to bring back to the lab. It was a very cold day, and much of the moss was actually frozen! 

After spending an hour in our early-succession site, we started walking away from the glacier into a mid-succession site. We make the same measurements there to understand how the plants and soil change as they develop over the years of succession. This is called a "chronosequence": when we use space to represent different amounts of time. In other words, the trajectory of walking from close to the glacier away from it towards the coast is like walking through time from recently-exposed soil into older ecosystems that have been exposed for longer periods of time. Those areas that have been exposed longer have had more time to develop a more complex ecosystem. The moss and plant coverage there is much greater, and you can get large "carpets" of moss that look so lush and inviting!

A springtail's-eye view of a moss carpet.

We were about halfway done with the mid-succession sampling when we were told that the weather was getting worse, so we had to go home before it became unsafe to use the boat. We came back to Base Escudero where we have been processing the samples in the lab. We will hopefully be able to return later this week to finish sampling the mid- and late-succession sites!