Polar Soils Blog

Getting Set Up

2009-12-19T12:43:00.002+13:00

I've been spending the past couple of days getting our laboratory set up and our field gear put together and running. Today I've been assembling the gas analyzers that we use in the field to measure CO2 flux (to measure processes like photosynthesis and respiration). I have to make sure I write down every piece we need to run the analyzers, because if I forget to take something to the field, we can't come back for it very easily! It's not a very exciting job to do, but it's very important to be as organized as possible before we leave for the field on Monday. (Luckily I have some fabulous Florida State gear sent by my cousin Simone to use while I do it!)
The green notebook I'm writing in (with a FSU pen) is lovingly called a "green brain" here. People always have their green brain in their pocket and use it to remember, organize, and plan EVERYTHING. I'd be in trouble if I ever lost my brain! It's how I remember what gear I need to pack for each field experiment, how much each piece of equipment weighs for transport in the helicopter, important phone numbers, GPS coordinates for our research plots, permit numbers for shipping samples... EVERYTHING!

Tomorrow is our last day in town before we head out to Lake Fryxell for our first day of field work. We have more organizing and setting up to do, and a lot of packing!

Arrival in Antarctica

2009-12-17T19:46:00.009+13:00

Jenn and I have arrived at McMurdo Station, Antarctica! On Wednesday, we woke up early in Christchurch, packed our bags and were driven to the airport. There, we boarded a U.S. Air Force C-17 and flew from New Zealand to Antarctica. The crew flying the plane were from McChord Air Force Base in Washington, and they were very nice to us, their "cargo". There were about 40 passengers on the plane- mostly scientists. We also flew with a bunch of cargo destined for the South Pole. The weather was great, so our flight was easy and on time. The view from the window was great once we got over the continent. This is a picture from the porthole above my head on the plane. It's part of the continent that is covered by an ice sheet (which is about 98% of the continent). Off on the horizon you can see the ocean with icebergs floating in it.

The mountain range that crosses Antarctica is (cleverly) called the Trans-Antarctic Mountain Range. Later in the flight, we were even allowed to go up into the cockpit for an even better view!
Then, after a 5-hour flight, we landed at Pegasus Airfield in Antarctica. This is an "ice runway". That means it's built on a sheet of very thick, permanent ice that covers the Ross Sea. So there's not even any solid ground under that ice holding the airplane up!
Here's Jenn in front of the C-17, right after we landed:We've been in McMurdo for one whole day now. We've spent a lot of time in various training sessions. There's a lot we have to learn about how to live in Antarctica, because it's so environmentally protected and the climate can be so dangerous. We've learned about everything from lab safety to light vehicle driving to how to throw out our garbage!

Over the next couple of days, we'll continue setting up the lab and preparing our supplies for the field. There are a few more trainings we have to do, too. Tomorrow morning Jenn leaves for "snow school", which is where she learns outdoor survival skills. Let's hope for good weather for her. Snow school is much more fun when it's sunny!

Time in New Zealand

2009-12-15T15:34:00.014+13:00

Today we were outfitted with all of the gear we need to wear while in Antarctica. The board in the top picture shows the variety of clothes they give us: everything from long underwear and socks to coats and hats. We have to try on all of the clothes we're issues to make sure everything fits. I practiced my "ninja look" with the polypropylene base layer we're given. We also have to make sure that all of the layers fit overtop one another comfortably. Underneath that big red parka and the windpants, I am wearing 2 pairs of long underwear, fleece pants, a long undershirt, and a fleece jacket. I was very toasty warm!

Our flight to McMurdo will be tomorrow at 9 AM (New Zealand time). That means we have some extra time to spend around Christchurch. My favorite place to go in is the Botanical Garden. It's summer here, so all of the flowers are in bloom. It smells wonderful, and it's so nice to enjoy the sunshine and greenery before heading to Antarctica.
Jenn and I also went to the Canterbury Museum, where we learned a lot about the history of New Zealand and its people. New Zealand was originally colonized about 800-900 years ago by Polynesians. So, the ancestors of native New Zealanders are related to the people of Hawaii and other Polynesian islands in the South Pacific. These early people lived in New Zealand (or Aotearoa, as they called it) by hunting a bird called a moa. These are large, flightless birds that only ever lived in New Zealand, but are now extinct because they were overhunted by the early people! These early moa-hunting people of New Zealand are called the Maori. They have a very unique culture with their own language, art, and traditions. They hunted the moa until they were driven to extinction, at which point they relied more on farming and fishing. They were great craftsman that made beautiful wood carvings and ornaments made from jade and Paua shells. Their lives of course changed a great deal when New Zealand was colonized by Europeans, mainly the British, about 250 years ago. This is very similar to the U.S., where the Native Americans practiced their own culture until it was interrupted by European colonists. But, many aspects of Maori culture still remain in New Zealand. Maori is still one of the official languages of New Zealand, and even New Zealanders of European descent know many phrases in Maori, and you find Maori translations of most information given on signs and notices. Some of their cultural legacies in New Zealand include the haka dance (a war dance with a lot of shouting), and their art is still very much a part of New Zealand culture.

Well, if all goes according to plan, we will leave for McMurdo tomorrow morning and my next blog post will be from Antarctica! All but one piece of our luggage has arrived. Hopefully the final piece will come today so that we land in McMurdo fully-prepared for the next two months!

Arrival in New Zealand

2009-12-13T18:24:00.004+13:00

Well, Jenn and I have made it safely to Christchurch, New Zealand. It has been a long two days and every leg of the trip ran a little bit late. Our bus was a little bit late getting to the Boston airport. We left Boston a little late, so arrived in Los Angeles a little bit late. Luckily there was still enough time to meet our connection to Sydney without any trouble (but no time to stop and eat dinner). Our flight left Los Angeles only about 20 minutes late, but landed in Sydney about 40 minutes late. That caused us to miss our connecting flight to Christchurch, NZ. They arranged for us to get a new flight to Christchurch, NZ on a different airline, but it was still a close connection due to our late arrival. When we arrived in Sydney, we had to be rushed off the plane and driven on one of those big golfcarts by airline employees to our gate. Luckily, we made the new flight on time! Unfortunately, our luggage didn't. So, when we arrived in Christchurch a couple hours later than planned, our luggage wasn't there! And to make it worse, the U.S. Antarctic Program's headquarters were closed by the time we got in! So, all we could do was head empty-handed to our hotel and wait until tomorrow morning.

Now, I am sitting in the lounge of our favorite B&B in Christchurch with a cup of tea and biscuits. Luckily I put a lot of necessities in my carry-on bags, so I have showered and changed my clothes after 48 hours of travel and I feel much better! Hopefully our luggage will arrive on the next flight from Sydney and we'll be able to pick it up tomorrow. Then, we can start enjoying our two days in New Zealand!

Now, it is time for dinner. Keep your fingers crossed that our luggage finds us before we leave for Antarctica on Wednesday!

And We're Off!

2009-12-12T05:23:00.001+13:00

We've begun our journey south! Jenn and I are on the bus to Boston now. The first leg of the trip has begun.

Almost Time to Leave

2009-12-11T06:46:00.003+13:00

We're all packed up to go! Tomorrow morning Jennifer and I start our 5-day journey to Antarctica. First, we fly commercially to Christchurch, New Zealand. We're getting routed from Boston, through Los Angeles and Sydney, Australia to get to New Zealand. It'll take a total of 33 hours from the time we leave Dartmouth until we arrive in Christchurch, but because of the International Date Line, we'll land there 2 days later.

Check out this interactive map if you want to find out more about our travel plans.

We'll be in Christchurch, NZ for 3 days before we finish our trip and fly to McMurdo Station in Antarctica. While in Christchurch, we'll get fitted for all of our Extreme Cold Weather Gear, receive some safety training, and of course enjoy some of that great New Zealand summer weather!

Let's hope the weather is good for our travels and that we don't encounter any major delays! I'll keep you posted.

One More Week!

2009-12-05T08:28:00.002+13:00

We are at the one-week mark! We leave for Antarctica on December 11, exactly one week from today. I'm finishing all of the labwork that needs to be done before I leave and getting the last of our gear packed up. It is a busy time for our group here at Dartmouth!

I'll keep you posted on our travels as we make our way across the globe.

Welcome to Season 3!

2009-11-17T08:17:00.007+13:00

Welcome to another field season of research in Antarctica with the Dartmouth polar soils research group!

We are making preparations to leave the U.S. and head to McMurdo Station on December 12. It is a busy time of preparations for us at Dartmouth! We have a lot of work to finish up, travel plans to arrange, and supplies and equipment to gather. In just a few weeks, we'll be on our way.

If you are new to the Polar Soils blog, here is some information that might be useful to you:

Where we go:
When most people think of Antarctica, they think of ice. When you're on the continent of Antarctica, it's referred to as being on the "ice." However, the area we study is a polar desert called the McMurdo Dry Valleys, where the glaciers have retreated. Just like deserts in the U.S., there's very little precipitation, so there's actually bare soil, not just ice and snow! The red dot on the map shows where McMurdo is located:

What we do:
Our research is in the field of soil biogeochemistry, which is just a big word that means we study the way nutrient elements move in the soil. We are especially interested in carbon, nitrogen, and phosphorus, since these three elements are so important for all forms of life. We study how the living organisms influence nutrients in the soil. All of the animals in the dry valleys are microscopic (except for the scientists, of course). While other areas of Antarctica have penguins and seals, the dry valleys' largest animal is a nematode. A predatory nematode is the top of our foodchain- the equivalent to a lion in the Serengeti! We also study the mosses growing in the dry valley soil. Mosses are the only plants growing in the dry valleys and the only living things you'll find above the soil- the equivalent to the redwood forests in America!

Who we are:
Our research team is a little bit different from last year. There are four soil scientists going to Antarctica from Dartmouth. The leader is Dr. Ross Virginia, a professor at Dartmouth who has been going to Antarctica for many years. Also on the team are me (Becky, a postdoc), Julia and Jen (both graduate students). While on the ice, we will continue to work very closely with another group of scientists from Colorado State University led by Dr. Diana Wall that specializes in the nematodes (they have a special nematode blog). Together all of us study the nutrients and biology of the McMurdo Dry Valley soils.

About the blog:
Our blog is designed to be an educational tool for elementary and middle school classrooms, but all readers are welcome to follow along! Teachers interested in using the blog in their classes are welcome to contact me (contact information available through my website, listed under my Profile on the bottom-right).
On the right-hand side, there are some links with additional information that is useful for both kids and adults. Many links are added throughout the season, so keep an eye on them!

Continuing the work back at Dartmouth

2009-03-15T07:44:00.007+13:00

We've been back at Dartmouth for about a month, now. Our soil and moss samples have been shipped from Antarctica so that we can continue to analyze them. We store the samples at Dartmouth in big freezers at -20°C (cold enough to keep their chemical properties from changing, so that they remain the same as when we scooped them up from the Dry Valleys).

We spend a lot of time in the lab performing our analyses. Here, I am weighing some soils into a tin to measure their moisture content. We will also measure the amount of nutrients, ions, microbial biomass, and many other chemical properties of the soils. We will then have to process the data and see what we learned from the field season. There will be graphs to make, papers to write, and new experiments to design from what we learn. It will take a lot of time, and will keep us quite busy until next December when it's time to head back down again!

I've also been to visit my friends at Thetford Elementary School, who followed my blog while I was in Antarctica. I was able to join their class for a morning to talk about Antarctic science, show photos and rock samples, and eat delicious home-made snacks. It was a great home-coming!

We're Done!

2009-02-01T19:22:00.002+13:00

Well, the field season is officially over! We have closed up the lab. We have shipped all of our samples. We've packed up our belongings. There's no more work to be done! Tomorrow we will fly back to Christchurch, New Zealand.

Tonight, we have to pack up our luggage and turn it over to the crew that will load the C-17. This is lovingly called "bag drag", because it involves dragging our orange bags up the hill to the transport building. There, everything is weighed (including us!), and our luggage is put on pallets to load onto the aircraft when it arrives. Tomorrow we will go back to the building with our carry-on luggage to be transported to the ice runway where we'll meet the C-17. It's a day full of waiting!

The last piece of business I had here at McMurdo was to show my new Wubble friend around town. The Wubble is visiting from Thetford Elementary School in Vermont. He learned a lot about Antarctica while he was here. I also learned a few things about Wubbles. I learned that Wubbles do not like wind! He had a hard time standing up for the photo... :)

Ok, it's time for bag drag! Keep your fingers crossed that weather and mechanics cooperate, and I make it back to Christchurch in good time!

How to Walk in the Dry Valleys

2009-01-31T16:51:00.000+13:00

The dry valleys are a very sensitive ecosystem. Because it's such a harsh place for organisms to live, they do not grow very fast. We don't want to make it any harder for them! Plus, we want the ecosystem to stay as clean and healthy as possible, without creating too much of a disturbance ourselves. We want to avoid damaging the ecosystem and the organisms as much as possible. Therefore have to be very careful when we work in the dry valleys.

The main way we can disturb the environment is by walking. We have to walk a lot to get to our camp and field sites for work. There are very specific ways we walk here to minimize the amount of disturbance we create with our feet.

When we're walking on the ground to and from our field sites, we always walk single-file so that only one line of footprints is made. We follow paths made by the polygon cracks in the ground. These cracks are made by the repeated freezing and thawing of the ground, and they form a variety of interesting shapes, called polygons. When you look at the ground from a helicopter, you see all of the polygons that make up the dry valley landscape.

Our previous research has shown us that soil biodiversity is lowest in these cracks. There are fewer animals living in the soil at the cracks than in the flat part of the ground. So, we try to always walk in the cracks. That way, our footsteps are trampling the least amount of organisms as possible. It unfortunately means that we can't walk in a straight line anywhere! You have to follow the zig-zagging of the polygon cracks to get from one place to another, which means sometimes you walk twice as much as the distance you need to go! Here's what it looks like as you walk in the polygon cracks:

When we're working at our field sites, we try our best to not trample the soil too much. We stand on rocks as much as possible. If we want to sit down, we sit on rocks, like Katie is doing:

Sometimes we work near streams, especially for our moss research. We don't want to disturb the algae and moss growing in the sediment in the streams. To avoid trampling anything, we rock hop. Every step we take has to be on a rock, where algae are not growing. This is pretty easy when the stream flow is low and the rocks are exposed, but it can get tricky if the water is high!

Sometimes we even have to rock hop to walk across the dry ground. The polygon cracks cover most of the soil, but they're not everywhere. When there are no cracks, we rockhop across the ground so that we don't disturb the soil!

Most of the places we walk are on soil and near streams. But, sometimes we walk on the ice. We don't have to be as careful about the ecosystem when we're on the ice, because there's not much damage we can do. But, we still have to be careful! The ice is slippery, of course, so we wear stabilizers attached to our shoes that give us better traction. Also, the glaciers and lake ice are covered with cryoconite holes. These holes are formed when dirt or rocks are blown onto the ice. Because the rocks are dark, they absorb more of the sun's heat and melt the ice around them. The rocks sink down as the ice melts, leaving a lot of little holes in the ice. These holes might be several inches deep, or even deeper! They can be just a couple inches wide, or they can be much bigger! It depends on the size of the rock that landed there to melt the ice. Sometimes the holes are filled with water. We have to be careful not to step in them, because if you do, you'll suddenly find yourself standing in a deep, wet hole! Sometimes the cryoconite holes have been covered back over with a layer of ice on top that maes the holes hard to see. But, that layer of ice is not strong enough to hold a person, so you crash through unexpectedly. You have to keep an eye on the ground so that you know you're stepping on thick ice. This is what it looks like to walk over the top of a glacier in the dry valleys. This is from our Christmas Eve hike over the Canada Glacier:

We do a lot of walking while we're here. Now you know what it's like!

Camp Hair Contest Winner

2009-01-31T11:14:00.004+13:00

The week has passed, and the votes have been tallied. The winner of the 2008-09 Best Camp Hair Contest is...

BREANA!!

This proud wormherder celebrates her victory by sporting her favorite facial hair accessory- a mustache! It's a very expensive mustache to have grown.Congratulations Breana!

Old Antarctic Explorers

2009-01-26T09:00:00.000+13:00

Antarctica has a long history of exploration. Explorers, mainly from Europe, were frequently coming to Antarctica during the late 1800's and early 1900's during what is called the "Heroic Age of Exploration". The goals of the explorations were mainly scientific. They wanted to study the geography of Antarctica and reach the South Pole. This was a very difficult time to be an Old Antarctic Explorer. Resources were scarce down here, working conditions were strenuous, and of course the weather was harsh! Explorations tended to be a feat of endurance, both physically and mentally. A lot of people died during expeditions to explore Antarctica and reach the South Pole.

One particular OAE that is important in the McMurdo area is Robert F. Scott. He led several missions to this area of Antarctica. After exploring a lot of this region, Scott led a party in an attempt to reach the South Pole. He was racing the Norwegian explorer, Amundsen, to be the first to reach the South Pole. Unfortunately, the trip did not go well for Scott. They did reach the South Pole, but they were beaten there by Amundsen's party. And, on the journey back to the coast (here at McMurdo), everyone in Scott's party died due to the harsh conditions. Surprisingly, they were only 11 miles away from a supply hut when they died. It is a very unfortunate story!
A statue of Scott is in Christchurch, NZ. We always visit it on our way down to the ice. Here's Katie with the statue, back in December when we were passing through.

A lot still remains of the early explorations. Near McMurdo, there is a hut that was built in 1902 by Scott during his first mission, called the Discovery Mission. The hut is called (cleverly) Discovery Hut, and sits on Hut Point just outside of McMurdo. Several huts like this were built around Antarctica to be supply stations for explorers along various points on their journey. It is Discovery Hut that Scott's South Pole party was trying to reach when they died.Because Antarctica is so cold and dry, these huts are very well preserved. The food and equipment that explorers used are still in the huts. We were lucky enough this year to be able to go inside Discovery Hut and see what's in there! Here's a video I took walking through the hut. You can hear Breana telling some facts about the hut and Katie asking questions. It's neat to see all of the old supplies, like what kind of food they eat and clothes they wore!

Some of the facts Breana is reading:
These huts were built in Australia, fashioned after Aboriginal huts that were designed to keep cool during the hot summers. Scott thought that it would work the same for keeping warm in cold Antarctica. But, he was wrong! The building was not warm enough for people to live in, so it was used for storage and cooking. Instead, the people lived on the boat just offshore. They heated the building with a blubber stove. That's the brick structure in the floor towards the end of the video. You can sort of see the huge chunk of freeze-dried whale blubber behind Uffe at the beginning of the tour (it's in a shadow, so hard to notice).

It was pretty neat to be able to see this little piece of Antarctic history. It's amazing to think about the conditions that the early explorers had to deal with. They're the same type of conditions we deal with here, but we're much better equipped now!

Winding Down

2009-01-25T17:08:00.002+13:00

Our field season at McMurdo is starting to wind down. Ross is leaving today to head back to the U.S. Katie, Elizabeth and I are here just one more week to finish up our work. We are scheduled to head back to New Zealand on February 2.

We have just two more days of field work left for this coming week. Other than that, we are processing the last of our samples and breaking down the lab. We are cleaning out the lab, returning field gear, and gathering up our shipments to send home. All of the soil and moss samples we've collected over the season are getting boxed up to ship back to Dartmouth. We will have a lot more work to do with them once we return home.

It will be a busy week!

The Dry Valley Forest

2009-01-22T20:31:00.013+13:00

As I've said before, Antarctica is a very hard place to live. It's not just hard for animals, but also for plants. It's very dry, so plants cannot get much water to grow. The only time water is plentiful is during the 14 weeks of the year when the meltwater streams are flowing, and that water is only available if you're right next to the stream. Sunlight is also a problem. During the winter there's no sunlight for photosynthesis, but during the summer the sun can be so intense that it can actually damage plants. So, it takes a very hardy plant to be able to grow here!

The only plants we have in the dry valleys are mosses. Very short mosses. There are no vascular plants, which are what most people think of when they hear the word "plant". Mosses mainly grow in patches along streams or beneath snow patches, which is only a small percent of the land area. They grow incredibly slowly. We're talking less than a millimeter of growth per year! Most of the moss we see look like the photo above from right outside the Lake Fryxell camp hut. They're not lush and green, because they're usually too cold, too dry, or have too much sun damage. But, sometimes you find a nice, lush green patch like the one below! This patch was probably recently uncovered from water, so is still very happy.

One of the really cool things about this patch of moss that Elizabeth, Katie, and Ross found is that it has reproductive structures. Moss is able to reproduce in two ways. It can reproduce by itself, where bits of the moss break off and become a new moss plant. In the dry valleys, these small bits of moss might blow in the wind to a new location, so that moss spread to new areas. Moss can also reproduce with each other. For this, the moss grow special structures. These special structures act like male and female parts, so that the sperm from the male structures fertilizes the female structures, forming spores (which are sort of like seeds in plants). When they're ready, the spores are released from the female structures to seed new areas. (Click here to see a video of moss reproduction.)

It is generally thought that moss in the dry valleys spread by pieces breaking off and becoming new mosses, not by developing spores. Growing the special reproductive structures requires a lot of energy and resources that are very hard to come by in the dry valleys. But, in this happy patch of moss, we see reproductive structures! Those white-ish stems coming up are the structures that contain the spores. Here's what one looks like under the microscope:

Moss is the only above-ground life in the dry valleys. All of the other organisms live in the soil, not on it. So, moss are in a way like the redwood forests of the Antarctic Dry Valleys! They are one of the few sources of food for soil organisms. When mosses die, they decompose in the soil, just like plants in warmer climates. The carbon and nutrients released from mosses when they decompose are probably a very important part of the soil food web. That is why so much of our research this year focuses on mosses. We want to know more about their role in the carbon and nutrient cycles in the dry valleys. We measure their photosynthesis rates, so that we know how much carbon they are taking from the air and putting into the soil. We measure their nutrients, so we know what type of food they are providing to the soil organisms. We measure how they respond to changes in moisture and nutrients in the soil, so that we know how stable their role is in nutrient cycles.To see how the nutrients in moss respond to changing the nutrients around them, we spray salt solutions that contain nitrogen or phosphorus onto the mosses (very similar to the stoichiometry experiment using the "hula" cones). Here's a patch of mosses next to one of the streams. It's buried in silt a bit, but there are mosses down there! Katie is spraying the nutrient solutions on them. While we were at F6 this week, we took samples from the plot to see if adding nutrients around the mosses changed the nutrient content of the mosses themselves. We also have these plots set up around a few other streams that we will have to sample in the next week.

2nd Annual Camp Hair Contest

2009-01-20T17:20:00.001+13:00

It is time for the Second Annual McMurdo Field Camp Hair Contest!

The water restrictions in the dry valleys means that we are not able to shower or wash our hair while we're out at field camps. That means that people's hair gets very dirty and oily, which of course leads to some very fabulous hair-do's! This is what we call having "camp hair." Having great camp hair is a matter of pride, and the person with the best camp hair is honored throughout McMurdo. So, once again, I'm going to leave it up to everyone reading my blog to decide who has the best camp hair for the 2008-09 field season. Review the photos below of our "camp hair" contestants, and send in your vote! Anyone reading this is welcome to vote, and can do so by sending an email with your choice to me.

Let's meet this year's contestants!

Elizabeth:Returning champion Elizabeth is once again demonstrating her all-natural, gravity-defying camp hairdo. While the front of her hair has been flattened by hours of lying under a hat, don't let that fool you! The back of her head is 4 inches taller than the rest of her! Photo taken after 5 days in the field.

Katie:Recent Dartmouth graduate Katie is featuring the Cindy Loo Who look. The dry air can't keep her hair down, oh no. This springy look comes after 5 days in the field under the influence of wind, sunblock, and home-made wool hats.

Corey:
With only 3 camp-showers over the course of his 40-day field stint, stream-team member Corey's hair has been dirtied, wind-blown and pelted by sand particles. Much like this ventifact. Coupling his hairdo with a savage beard, Corey presents a look that is hard for our other gals to match.

Breana:This wormherder postdoc's look just screams "Troll Doll". Breana does not need multiple days without a shower to master this fine look. On Day 1 in the field, this is her hair's reaction to a mere few hours of being trapped under a hat. When her hair is released from under her hat, watch out!

There they are: the 2008-09 season's Best Camp Hair contestants. May the voting begin! The champion Camp Hair will be declared a week from today.

2009-01-20T17:11:00.002+13:00

After a full day of weather delays on Saturday (and our wonderful luau), we finally made it back out to F6 on Lake Fryxell. However, the bad weather took out our internet! We finally had IT guys come in today to fix it, so we've been reconnected with the outside world.

We've been busy with lots of field work for the past several days. But, it's been very cold! I'll catch you up on all of our work since we lost connection over the next few days. Right now, it's time for a hot drink and some dinner!

More Weather Delays

2009-01-17T09:56:00.005+13:00

The weather has been very uncooperative for the past week and a half! It was hard getting everyone back into town after our field work last week, because the weather was bad and the helo's couldn't fly. Katie, Elizabeth, and Ross got stuck out at Lake Fryxell camp for an extra day because no helo could get into the Valley to pick them up. I kept trying to leave McMurdo to go to Lake Bonney, but that trip kept getting canceled. We finally made it to our destinations, after a couple days of delay. We all made it back to McMurdo on Tuesday, after completing most of the work we needed to do last week. Since then, we've all been back in McMurdo processing samples in the lab. Today, we are once again trying to get back to the field. We were all supposed to fly out this morning to F6 camp on Lake Fryxell. But, it's snowing again, and you can only see about 200 m across McMurdo Sound, so we're not going anywhere!

Since we're all stuck here in town, we decided to have a luau on the Florida Keys (after my walk to the post office to pick up some super fun packages that were sent to me). We decorated ourselves using my Luau in an Envelope kit. And we basked on the edge of the miniature beach that was sent to me from Florida (which I'm holding in my hands). Here we are partying in the hallway in the science building: Karen, Katie, Diana, Breana, Uffe, me, and Bishwo. Of course, we also decorate any passers-by, so now there's a lot of people in the science building in Antarctica that are dressed for a luau!There's still a small chance we could get out to F6 later today. But the weather is not looking so good, which means we may be stuck in town until Monday. I'll keep you posted!

Nitrogen Fixation

2009-01-15T17:42:00.014+13:00

Nitrogen is the most common element in the atmosphere and the air we breathe (78%), and it is a necessary element for life. It is an important element in proteins and enzymes, including the enzyme that allows plants to photosynthesize. However, the form of nitrogen that is in the air is not usable by plants. Plants use nitrogen compounds in the soil, not the nitrogen gas that is so abundant in the air. So how does all of that nitrogen from the air get into the soil for plants to use?

There are some organisms called cyanobacteria that can use the nitrogen gas in the air. They have special cells (called heterocysts) that can can grab nitrogen gas from the air and change it into a usable compound. This is a process called "nitrogen fixation". The cyanobacteria use that new form of nitrogen to grow. Then, when the cyanobacteria dies and decays, that usable form of nitrogen is released in the soil for plants and animals to use.

We see a lot of cyanobacteria near the streams and lakes in the dry valleys. It will grow in thick mats, like you see here. All of that black stuff is a bunch of cyanobacteria matted together, making a layer on top of the soil. One of the things we want to know is how much nitrogen the cyanobacteria are fixing. That way we can estimate how much nitrogen they are adding to the soil for the mosses and other soil animals to use. Unfortunately, it is not very easy to measure nitrogen fixation. But, we can measure a similar chemical process called "acetylene reduction" that helps us calculate how much nitrogen is being taken from the air. To measure acetylene reduction, we place small amounts of cyanobacteria (and mosses with cyanobacteria growing on it) into air-tight chambers, like the clear plastic ones in this picture. We then add a gas called acetylene to the chamber. The cyanobacteria will change the acetylene to ethylene in a process similar to how they change nitrogen gas. We leave the pieces of cyanobacteria and moss in the chambers for 1-5 hours. Then, we take a sample of the air inside the chamber and put it in a special vial. We then measure the amount of acetylene that has been changed to ethylene, and we can then calculate how much nitrogen would have been fixed from the air.

Here's Elizabeth and Ross measuring acetylene reduction at one of our field sites. Elizabeth is using a big syringe to pull new acetylene from a bag to inject into the plastic chambers. Ross is using another syringe to remove a gas sample from a chamber that contains some cyanobacteria.
We will take the vials of gas samples back to Dartmouth and measure the concentration of ethylene on one of the machines in our lab at home. So, we're doing the work now, but won't see the results for another month!

Dry Valley Wildlife

2009-01-12T09:28:00.015+13:00

Most people think of Antarctica as being a big, cold, dead place. When you see photos of our research in the dry valleys, you don't see animals. But, there are animals there, in every single one of those pictures! You just can't see them, because they're microscopic. Here's some information about the main types of micro-organisms that live in Antarctic soils.

Nematodes
Also called roundworms, nematodes live EVERYWHERE in the world. You can find them in every biome in the world. They live in water, soil, ice, even in other animals! They are the most abundant animal in the world. In the dry valleys, we find more nematodes than any other animal. They are what our collaborators at Colorado State focus on studying. We have three main species that live here. The most numerous species, Scottnema lindsayae, is in the photo to the left.

Nematodes eat a lot of different things. Some, like the guy at the left, eat bacteria. Others eat fungi or algae, and some are even predators that eat other microscopic soil organisms. In the dry valleys, a predatory nematode is the top of the food chain! Though nematodes are small, they have a lot of very well-defined characteristics. Here is a very close-up picture of the mouth-parts of a bacterial-feeding nematode. They use those long branches on their mouths to scrape bacteria off of soil surfaces.

Rotifers
Rotifers also live in a lot of different environments, including fresh water, saltwater, soils, and other watery environments. A rotifer eats by waving the hairs around its mouth (at the top, in this picture) to catch things floating in the water. The moving action around their mouth looks kind of like a wheel, which is how they got the name ROTifer (like rotate). The "foot" (at the bottom of the picture) is to anchor the rotifer when it doesn't want to move.

Tardigrades
Tardigrades are also called water bears, and looking at the picture I think you can see why! They even have claws at the end of their feet, which you can see in this very close-up microscrope picture that Uffe took of a tardigrade foot. The claws let them hold on to something as they float through water or the water-filled spaces in the soil. Tardigrades eat with a stylet that they use to pierce animal and plant cell walls.

Tardigrades are able to live in a lot of extreme environments, and are found everwhere from the Himalayas to the ocean floor to Antarctica. They can withstand the pressure of a vaccuum, radiation, dehydration, and both incredibly high and low temperatures. There are even experiments that test tardigrades' ability to live in open space! In the dry valleys, they especially like to live in the moss and algae patches, where food and water are readily available.

The soil environment in the dry valleys is a very hard place to be an animal. There's not a lot of water, not a lot to eat, and it is very cold! Most of these micro-organisms have a special ability to help survive in such a harsh environment. They can go into anhydrobiosis, which essentially means they can freeze-dry themselves. They can push out all of their water and curl up, so that they don't freeze and die. Their metabolism drops to almost a stand-still! They can stay in anhydrobiosis for a very long time, and immediately wake up if water becomes available.

Part of our research looks at what animals are living in the soil. We want to know why they live in some places in the dry valleys, but not others. We want to know how nutrient cycles in the soil change when animals are there or not. So, we spend a lot of time on the microscopes looking at the animals we can extract from the soil. One of our team members, Byron, made this awesome video through the 'scope featuring three of our soil superstars: nematodes, rotifers, and tardigrades.

Tracer Experiment

2009-01-09T21:02:00.005+13:00

Well, we finally made it out to the field. The weather at McMurdo has been very patchy. There's been snow and a lot of clouds. But, the weather out in the Dry Valleys has been very nice. So, once they finally had a short window of time to get us out, we left McMurdo and have been staying in the Valleys ever since in some beautiful, sunny weather. Katie and Elizabeth made it out to Lake Fryxell on Wednesday afternoon. Ross and I made it out to Lake Bonney on Thursday afternoon.

At Lake Bonney, Ross and I were working on an experiment that traced the movement of water from melting permafrost flowing over the soil. Permafrost is soil and rock in the ground that stays permanently frozen year-round. It usually is found below the soil surface in cold places like Antarctica and the Arctic. During the summer in the dry valleys, the permafrost will melt a little bit, causing wet patches to appear in the soil. You can see those darker, wet patches of soil in this picture at Bonney:Because it's been so warm this year, the permafrost below the soil has been melting a lot more than usual. At one of our research sites at Bonney, that meltwater has reach the surface (kind of like a spring you might find in the mountains in the US). There's so much meltwater that it ended up forming a stream that flows all the way down to the lake, straight through some long-term sampling plots we set up years ago! (Our team nickname in McMurdo is the Wormherders. Because the stream flows through one of our plots, it is called Wormherder Creek.) Instead of being upset that our plots are ruined, we're using the opportunity to learn about sources of water in the dry valleys and how they influence the soil.

On Thursday, we soil ecologists teamed up with a group of stream ecologists to study how the new Wormherder Creek interacts with the soil to influence soil chemistry and organisms. We added chemicals containing lithium and bromide high up on Wormherder Creek, and we followed how those chemicals moved down the stream and through the soil. There were two people at the top of the creek at the chemical injection site running the pump. Then, there were scientists stationed at regular intervals down the stream collecting samples every 5 or 10 minutes. I was stationed higher up on the creek with Uffe. In this video, you see Uffe labeling the bottle to take the next sample. That bottle gets dipped into the stream flow to be filled with water. You can see another scientist, Anna, further down the stream at the next station. You can also see how fast that meltwater is moving! It's a small creek, but there's a good bit of water in it! The tube next to the orange flag is called a piezometer, which is how we extract ground water from below the surface.

We collected a lot of surface water, ground water, and soil samples for several hours through the night. We will look for the presence and concentration of the chemicals we released high up in the stream so that we can follow how the water moved down to the lake. We will also measure the chemistry of the water and soil, and look at what kinds of organisms we find in various locations, to see how those important properties are influenced by the presence of Wormherder Creek. It was a loooong night, but we finished it!

After we left Lake Bonney late Thursday night, Ross headed to Fryxell to be with Katie and Elizabeth. I have been back at F6 (across the lake from the rest of the group) working on the stoichiometry plots that we treated last week. Hopefully I will be heading back to Lake Bonney tomorrow, but the weather does not look good in McMurdo, so the helicopters may not be able to come get me! Keep your fingers crossed, because I have samples to get back to the lab!

My bags are packed, I'm ready to go....

2009-01-07T08:16:00.010+13:00

Because the Dry Valleys are so remote, we fly on helicopters to get there. Today we were supposed to fly to Lake Fryxell and Lake Bonney. But the weather is very bad for flying right now so we can't go anywhere. Helicopters only fly when the sky is clear and the wind is not blowing too hard. The helicopters here at McMurdo have lots of jobs to do, such as taking people to different places, delivering packages to field camps, and moving large pieces of equipment. Even though the helicopters have many jobs to do, safety is more important than everything else. So if the weather is bad enough, they all stay on the ground. Usually from the helicopter pad you can look out at the Ross Sea and also see the mainland on the other side. As this picture shows, you can't see much of anything this morning.

Last night we got a few inches of snow in McMurdo, even though it's the middle of summer!

We come down to Antarctic with plans to do lots and lots of scientific research, the weather is unpredictable. Sometimes we simply can't get out to our field locations and must wait for the weather to clear. So that's what we're doing today... waiting for better weather!

In and Back Out Again

2009-01-06T14:46:00.005+13:00

Our final team member, Ross, arrived Saturday night. So, we are now a complete group of 4 from Dartmouth! Together, we've spent the past couple of days in McMurdo in our lab processing our samples.

Katie is working on a procedure called Chloroform Fumigation Extraction. For that, she is measuring the amount of carbon in the soil that is released after adding chloroform. Chloroform is a chemical that breaks open cells of living organisms (including people). So, if the carbon is released by the chloroform, it was released by the microbes living in the soil. Measuring the amount of carbon released by chloroform gives us an estimate of the microbial biomass living in the soil we are studying. Of course, Katie has to be careful not to breathe the chloroform herself. (Don't worry: when this picture was taken, she was already finished with the chloroform step!)
Elizabeth is busy picking all of the rocks out of her soil samples. The soils she is studying are very rocky, and the pebbles have to be removed before she can measure their chemistry. Doesn't that look like fun?!

We will be heading out to the field again tomorrow. We will be splitting up into two groups so that we can get more work done. Katie and Elizabeth will be going back to Lake Fryxell where we went the first week of our field work. Ross and I will be moving around all over the valley for the rest of the week. We'll be busy!

~~~~~~~~~~~~On another note~~~~~~~~~~~~~
Check out the awesome card I got in the mail yesterday, drawn by my friend Bob! Cedar waxwings like these live in the trees outside my office back at Dartmouth, so I put the card over my desk here in McMurdo to remind me of home.

Now where was that?

2009-01-04T19:14:00.007+13:00

The plants and animals that live in the Dry Valleys are very small. Because they are so small, they are often difficult to locate, and even more difficult to find a second time.

This picture shows how closely you have to look to find the mosses that we study.

There are also no road signs pointing us in the direction of our research sites. We study certain spots in the field during one research season and try to get back to those same locations the next year. This is challenging because there are very few land features that we can use to remember a certain location and some things change from year to year. The streams are fed by melted snow, so they change depending upon how much snow falls during the winter and melts in the summer. This stream might have looked completely different last year, so finding a particular bend in the stream is nearly impossible.

Because of these navigational challenges, we use a GPS to help us find places in the Dry Valleys.
GPS stands for Global Positioning System. It uses satellites orbiting the earth that transmit signals, which enable GPS receivers to determine their current location. A GPS tells you your location in latitude and longitude coordinates. When we want to be able to find a certain spot again, we record the latitude and longitude coordinates so that we can later return to that exact location using the GPS.

Here's a picture of Elizabeth using a GPS to record the coordinates of a study site. If she wants to come back later, all she has to do is tell the GPS to find those coordinates and it will point an arrow in the direction we need to walk to get there. It also tells you distance.

A GPS isn't perfect. Sometimes we have a really hard time finding a spot using the coordinates a GPS gives us. It is often about 10 meters off, which is a lot when your study subject is only 1 centimeter tall. But the GPS is a very useful tool and we are very happy that it's in our scientific toolbox!

Stoichiometry

2009-01-02T17:01:00.005+13:00

This morning, Katie and I flew to the Lake Bonney basin for another two days of field work.
While we are here, we will be working on a project that will tell us how the soil and soil organisms respond to nutrients added to the soil.

There are three main elements that are very important for life everywhere: carbon, nitrogen, and phosphorus. These nutrients are important for all organisms to grow and live. If one of these elements is in short supply, organisms cannot continue to grow. So, the amount of nutrients in the soil can be limiting to life. We want to know which of these elements are limiting to life in the dry valleys.

We have set up areas where we add carbon, nitrogen, and phosphorus to the soil. Each year, we add more of the nutrients and measure how the microbes and invertebrates living in the soil respond to the additions. We add the nutrients by dissolving sugar and salt in water, then pouring the water over the plots. Some plots get sugar water (for carbon), some get water with nitrogen or phosphorus salt added, and some get both sugar and salt. In this photo, Breana is adding some nutrient water to one of the plots.

We use the plastic cone to prevent the wind from blowing the water away before it reaches the ground. Or, you can be like Uffe and wear the cones as a hula skirt:
After we add the nutrients, we measure respiration to see how active the microbes are. We also measure the amount of nematodes in the soil and how the soil chemistry changes after the nutrients are added.

We've been working on this project for many years. So far, we have learned that carbon is most limiting to life in the dry valleys. Carbon in the soil mostly comes from photosynthesis by plants. Plants are able to take carbon from the air (as carbon dioxide) and turn it into forms usable by soil organisms. Because Antarctica is so cold and dry, there are not a lot of plants. We only have some mosses and algae that can photosynthesize, and they are only found near sources of water. Because there's not a lot of photosynthesis, there is not a lot of carbon added naturally to the soil. So, carbon is often the limiting nutrient in the dry valley soils, which is why we notice the biggest response in the activity of the organisms when we add carbon.

Nitrogen and phosphorus may also become limiting in the soil, if there is enough carbon for organisms to use. That is why we look at all three of the nutrients. We want to know how increases in all three nutrients might influence soil organisms. Which nutrient is most limiting might not be the same everywhere in the dry valleys, since the different areas have different geology. Hopefully this project will be able to tell us which nutrients are limiting in the different areas.

Katie and I are only at Bonney through tomorrow, then it's back to McMurdo to process our soil samples that we collect here. Hopefully, the final member of our team will arrive tomorrow. Ross's flight should be arriving tomorrow afternoon as we're returning from the field. Let's all hope that the good weather continues!