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For one month in Greenland, our most important scientific instrument was a paint brush.

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Painting pollen onto Dryas integrifolia.

With our brushes loaded with pollen, we brushed the stigmas of hundreds of flowers, essentially acting as human pollinators. I am using this pollen-supplementation experiment to figure out if flowers could produce more seeds if there were more insects visiting flowers.

One flower we are studying is Dryas integrifolia, which is a butter-colored flower in the rose family (Rosaceae). It blooms early in the season, which is important for early emerging insects that are potential pollinators, including flies, bees, and yes, even mosquitoes.

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Working with Dryas early in the season requires down jackets and a good attitude!

Once we were done painting, we waited for the flowers to close up and produce seeds. Dryas seeds are wind-dispersed, like dandelion seeds. So there was a narrow window of time in which we could collect the seeds before they flew away!

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If Dryas produces seeds, it creates little twirls that remind us of unicorn horns or troll hair (right). If the stem aborts, it creates little white tufts (left).

Great news: today we successfully collected the last of the seeds! Other news: now I have thousands of seeds to count! [ Volunteers welcome 🙂  ]

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Collecting the last of the Dryas seeds right near the margin of the Greenland Ice Sheet.

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For the past few years, my time in Kangerlussuaq has been very busy and well organized. Last year, in order to measure over 11,000 lichen diameters and collect over 300 soil samples, I maintained a strict schedule, spending full days in the field and taking only one day off per week (in order to shower, download photos, write blogs, and do laundry). After all, when your field sites are so far from home, and your field season is so short, you better make the most of it.

This year, however, since my soil erosion project is wrapping up, I have had minimal field goals. My focus, instead, has been working with the JSEP students, a group of awesome high schoolers from Denmark, Greenland, and the US.

JSEP students roast marshmallows during their camping trip. Working with these high school students has been a highlight of my field season.

JSEP students roast marshmallows during their camping trip. Working with these high school students has been a highlight of my field season.

With my mind not consumed by the frenzy of data collection, I’ve had time to think big. I’ve had time to wonder, ponder, question, plan, dream, devise. Time to imagine the science questions I’d ask if resources were unlimited. I’ve been pondering the difference between north- and south-facing slopes, wondering about the hydrology of such an arid landscape, devising systems to monitor the permafrost. I’ve been dreaming of returning here in the winter to look at snow cover, planning experiments to test how well shrubs can colonize eroded patches.

Big thinking is best done with colleagues. Here Rebecca investigates the soils around Kangerlussuaq, getting to know the dry soils so different from other Arctic systems.

Big thinking is best done with colleagues. Here Rebecca investigates the soils around Kangerlussuaq, getting to know the dry soils so different from other Arctic systems.

Big thinking is very different from the detail-oriented thinking of fieldwork, but it’s just as critical to good science. The creativity required to ask new and interesting questions is a skill often overlooked, rarely taught or discussed. During our fast-paced field seasons, stopping to ponder may seem like a waste of time. Yet how will we devise our next project unless we do? Returning home now, full of new questions and ideas, I’m pledging to always push myself to think big.

I've also had more time to sketch during this field season -- an activity that helps me to think big by forcing me to look at the landscape from new perspectives.

I’ve also had more time to sketch during this field season — an activity that helps me to think big by forcing me to look at the landscape from new perspectives.

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Welcome to Part 2 of our Special Edition Q & A


Thanks to the inquisitive minds of Windsor VT middle school students, we’ve received a whole new supply of Antarctic questions!


1. What does “avoiding skuas training” look like?

Well, unfortunately it probably sounds way more exciting than it actually was! We didn’t get to practice dodging flying objects, nor did we take turns role-playing an angry Skua (although someone should probably suggest these things for next year). Instead, Skua-avoidance was just discussed as part of our “general safety training”, where they basically told us that these birds will attack if they get the sense you are carrying food. So to avoid giving them that sense, we have to make sure we don’t waltz out of the cafeteria so preoccupied with stuffing cookies in our mouths that we’re oblivious to the giant hungry gull soaring towards our heads. (Yes, we’ve actually witnessed this). Skuas seem to really enjoy taking people by surprise, so our best defense is keeping food hidden and one eye to the sky.

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Slightly disappointed that he couldn’t steal our food, this Skua flies off to scrounge elsewhere.

2. Do certain colors mean different things about the plants, such as dying or living?

Great question. Even though it’s a cold dry desert, we see lots of colorful life out here…but most of it is pretty small in size and close to the ground or water. There are no shrubs, trees, leafy or flowering plants, but there are lots of species of mosses, lichens, algae, and bacteria that thrive in these harsh conditions. And these are the types of organisms creating the colorful patches we see near ponds and stream-beds. It’s pretty tricky to tell which are alive or dead because each type has a different set of pigments that give it that unique color. Sometimes these colors can be a little counter-intuitive – where we live in the Northeastern US, we usually see brown, black or orange leaves that die and fall off the tree each fall. But out here there are species that regularly grow with those colors! We see bright orange microbial mats that line the bottom of streams and ponds like a thick carpet. There are dark black leafy mats that look like crusty dead matter, but are actually alive. Some of these organisms grow in very shallow water which makes them extra exposed to sunlight and UV-radiation. This can damaging to them, just like it is to us. So to combat this they make special pigments that act as sunscreen, protecting them from the constant bright light of summer months. And sometimes even the dried and shriveled-up material at the side of streams are actually specially adapted to survive total dryness, so they may come back to life in the presence of water!

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Black, red and orange mats lie in a tiny bit of water on the margin of a stream-bed

3. Do different color plants (besides green) have chlorophyll?

This is actually one of the reasons microbial mats are so unique and interesting! The mats we mentioned earlier are built like a sandwich with multiple layers, and each layer contains different kinds of bacteria and pigments. These allow them to maximize their growth even when conditions in the environment change – for example, mats often have protective sunscreen pigments on the top layer (where they’re more exposed to solar radiation), and chlorophyll or other pigments tucked away in the lower layers (more protected from harmful UV radiation). So often when you flip over a bright orange mat, you may actually see bits of green underneath. In fact, some bacteria will actually move up and down within the mat, which may be a way for them to escape intense solar radiation during certain times of year.

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A large microbial mat shows off different shades of orange on the side of a small pond

4. How is it able to get sunlight through the ice? And do plants in Antarctica have special adaptations to help them grow?

Yes, ice can definitely reduce the amount of light entering the water. If the ice is thin and clear and the water is shallow enough, organisms with specialized light gathering pigments can still absorb enough to perform photosynthesis. But anything living underwater in Antarctica has to deal with drastic extremes in light (from total darkness in winter and under ice, to ultra high light in shallow ponds in summer). Plus, many water bodies are frozen all the way to the bottom in the winter, freezing these complex underwater structures in place. So to deal with these challenges they have lots of special strategies, such as producing cold-shock and anti-freeze proteins that protect them when the water around them freezes, or using specialized pigments that work extra-efficiently under low-light conditions.

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Here at the end of the glacier sits Lake Bonney, which is frozen even on this bright summer day.

5. What is the reason why microbes have certain colors?

The color of microbes is due to the different colored substances inside the cells. Each substance absorbs and reflects different wavelengths of light, and we see the colors reflected. Chlorophyll reflects green light and absorbs the other colors, giving plants their green color. Cyanobacteria are unique because they perform photosynthesis much like plants. These bacteria got their name because they have special pigment called “phycocyanin”, and this gives them that blueish-green color. But bacteria also use pigments for functions other than photosynthesis, like protection against UV or antioxidant activity.

6. Do micro organisms affect the color of the streams? 

Good question –actually any bits of material in the water can affect the stream color as they absorb and reflect light. Often when large amounts of bacteria are healthy and growing they can cause water to look brown or green, although this happens a little less in streams where the water is constantly moving. But in lakes and ponds during the summer this can be dramatic – have you ever seen the water turn green in lakes near you? Because the water is very cold and often nutrient-poor, streams and lakes in Antarctica tend to be pretty clear water. But if you look at the bottoms of water bodies down it’s a different story – that’s where all the colorful mats and microbes hang out.

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Long filaments wave like green strands of hair in the shallow water of this Antarctic stream.

7. Why do the microbial leaf mats look like rocks?

Mats come in a wide range of shapes, colors, and sizes. I think some resemble leaves, others definitely look like rocks, there are flat mats that cover the sediment like a big shag carpet, and there are strange tubes that grow vertically like underwater towers. It’s not clear exactly why each of these has such a unique shape and growth pattern, but most likely they all position themselves in a way that maximizes their ability to do things like absorb nutrients and light in their environment. The result is pretty elaborate!

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A view of one of many small melt-water ponds in the Miers Valley (can you spot all the orange mats?)

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Then, just under the surface of that same pond you get a new perspective – thick mats completely take over, covering the sediments, growing in all dimensions, and creating an underwater microbial city.

8. Do you need a special camera to take underwater pictures?

Yes! I use a GoPro with a waterproof case to take underwater footage. And since the water is very cold, I try to mount the camera onto a long rod so that my whole arm doesn’t go numb in the process!

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The GoPro allows me to snap some shots of the underwater life in ponds and streams.


Thanks again to all the excellent questions & stay tuned for Part 3!

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In previous blogs, I’ve hinted at the goals of my research, but have left a lot of questions unanswered. Why study phosphorus cycling in the first place? Where does this phosphorus come from? What guides my soil sampling when I’m in the field? I’ll try to answer many of these questions below, but please post if you’re still wondering!

One of my many sampling sites in Garwood Valley. Why did I pick this spot? What am I looking for when deciding where to sample?

One of my many sampling sites in Garwood Valley. Why did I pick this spot? What am I looking for when deciding where to sample?

All life on Earth (that we know of) depends on phosphorus and other essential nutrients. Even life in the Dry Valleys, adapted to extreme conditions and limited resources, couldn’t survive without it. Everywhere on Earth, the available phosphorus organisms can use ultimately comes from igneous rocks. Getting the phosphorus out of those igneous rocks (where it’s mostly locked up in a mineral called apatite) and into the ecosystem is a long process. Soil scientists are interested in understanding how quickly new phosphorus can enter the system. As you might expect, there are a lot of factors at play: the amount of apatite in the igneous rock, the speed at which that rock can break apart physically and chemically, the presence or absence of organisms that might help in dissolving the apatite…and we could go on.

Scientists have names for all of these factors influencing a current soil: relief, time, organisms, parent material, and climate. Each factor might be at play in determining the amount of phosphorus available in Dry Valley soils.

Scientists have names for all of these factors influencing a current soil: relief, time, organisms, parent material, and climate. Each factor might be at play in determining the amount of phosphorus available in Dry Valley soils. Drawings by Ruth Heindel

In the Dry Valleys, we are in a unique position to answer questions about phosphorus cycling because of the relative simplicity of the ecosystem and some interesting differences in parent material (or type of igneous rock) and landscape age. Let’s consider parent material first. Here on Ross Island (where McMurdo Station is located), we are close to the source of some extremely unusual volcanic rocks, including kenyte. Not only is kenyte very distinct in its appearance, but it is also distinct in its composition, containing way more apatite (and thus more phosphorus) than other igneous rocks.

Two pieces of kenyte, the most distinctive rock of the Dry Valleys. These days, my eyes are trained to pick out this dark rock from far away. It's always exciting to spot one!

Two pieces of kenyte, the most distinctive rock of the Dry Valleys. These days, my eyes are trained to pick out this dark rock from far away. It’s always exciting to spot one!

Although the source of kenyte is Mt. Erebus and other nearby volcanoes, past glacial activity has scattered kenyte (and other phosphorus-rich volcanic rocks) all over the Dry Valleys in very interesting patterns. Since there is no vegetation, and kenyte is a very dark rock, these patterns are clearly visible both on the ground and from the air. Dark soils containing lots of kenyte are noticeable in Taylor, Garwood, and Miers Valleys, just to name a few.

In Taylor Valley, patterns of dark kenyte-rich soil are clearly visible from a helicopter.

In Taylor Valley, patterns of dark kenyte-rich soil are clearly visible from a helicopter.

Do these dark soils contain lots of phosphorus that organisms can use? Or is all that phosphorus still locked up in the rocks, unavailable to life? This season, I’m trying to answer these questions by collecting samples from the dark kenyte-rich soils to compare their phosphorus content with the amount found in the lighter kenyte-poor soils.

A large disintegrated boulder of kenyte. Does the soil under this rock contain more available phosphorus than the soil away from the rock?

A large disintegrated boulder of kenyte. Does the soil under this rock contain more available phosphorus than the soil away from the rock?

But parent material isn’t the only factor that could influence phosphorus availability. The more time a soil has to develop, the more time phosphorus has to be carried away by water or wind, or taken up by an organism. Older landscapes generally have less total phosphorus than younger landscapes. Or what about the organisms living in the soils? Some microorganisms will excrete enzymes that help to break down apatite, releasing phosphorus into the ecosystem in a form that they can use. What if there are more of these organisms in one soil compared to another? This season I’m also trying to address some of these other factors. I’m collecting samples on landscapes of different ages to look at the influence of time on phosphorus availability. And I’m collecting samples for a colleague who will take a look at the apatite-dissolving enzymes in the soils to consider the influence of organisms on phosphorus availability.

The area around Hjorth Hill gave me the opportunity to sample soils of different ages. Soils higher up on Hjorth Hill are thought to be much older than the soil in the foreground.

The area around Hjorth Hill gave me the opportunity to sample soils of different ages. Soils higher up on Hjorth Hill are thought to be much older than the soil in the foreground.

Even in a relatively simple ecosystem like the Dry Valleys, teasing apart all of these soil forming factors is extremely complicated. While I don’t expect to solve every riddle this season, I am hoping that the boxes of samples I’ve collected so far will contain some clues into phosphorus cycling in the Dry Valleys!

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Although reacquainting myself with the familiar landscape around F6 camp was a great way to spend a few days, exploring new territory is always exhilarating. A few days ago, Jess and I were lucky enough to spend a day on the shoulder of Hjorth Hill – an area I had only explored on maps. Even my colleagues couldn’t give me much guidance – none of them had been there before either. With our maps, GPS, and sampling equipment, Jess and I headed out for an adventure.

After landing at Hjorth Hill, Jess is ready to head out on an adventure!

After landing at Hjorth Hill, Jess is ready to head out on an adventure!

Why did I want to explore Hjorth Hill in the first place? I am interested in what controls the amount of phosphorus available to organisms living in soils. Previous work has identified two main possibilities: landscape age (the length of time a soil has been developing) and parent material (the rock type a soil develops from). Hjorth Hill presented the opportunity to test both of these possibilities: two different parent materials of the same age right next to the same parent material of two different ages. My hope was to be able to collect samples of all these soil types, while giving Jess the opportunity to collect water samples. Thankfully, luck was on our side!

Landing at Hjorth Hill also gave us a new perspective on familiar territory: the view back into Taylor Valley.

Landing at Hjorth Hill also gave us a new perspective on familiar territory: the view back into Taylor Valley.

Our good luck started with the weather: it was clear enough to fly, but the top of Hjorth Hill was totally socked in (or, as our helicopter pilot put it, “the clouds were a bit dodgy”). This meant that instead of our original plan of landing at the top of the mountain, we had to discuss an alternate landing spot with our pilot. Once Paul learned that Jess was hoping to collect water samples, he chose the perfect location: a flat area on the shoulder of Hjorth Hill right next to numerous small meltwater ponds. Not only that, but all of the ponds hosted thick algae mats in all shapes and colors. Jess was in heaven.

The meltwater ponds were incredibly productive, with all sorts of algal mats growing along the shores.

The meltwater ponds were incredibly productive, with all sorts of algal mats growing along the shores.

Jess records the water temperature of one of the small meltwater ponds. Ice sits at the bottom of the pond.

Jess records the water temperature of one of the small meltwater ponds. Ice sits at the bottom of the pond.

Landing in unfamiliar territory is disorienting. It’s hard to match what’s on the ground with what is on a map, especially when the terrain is so bumpy. Fortunately, I had marked a few locations on my GPS before heading into the field, so we started hiking toward one of those. As we began walking, I felt confused – how would we know if we crossed over into another soil type? There didn’t seem to be much to guide us. Suddenly, however, the ground surface changed beneath our feet. Looking back, Jess and I realized that we had crossed over a moraine. We were clearly on a different parent material. Slowly, the pieces started coming together.

The ridge separating two noticeably different parent materials.

The ridge separating two noticeably different parent materials.

Of course, spending just one day at a site isn’t nearly enough to get to know it. I’d love to return to Hjorth Hill to spend more time exploring. But for now, we’re eager to analyze our samples to learn what Hjorth Hill has to tell us.

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Southern migration.


After four days of bouncing through airport terminals, Ruth, myself, and the members of the LTER soils team (http://www.mcmlter.org/) have come to our southernmost Antarctic destination at last!

Now, truly seasoned travelers (i.e., polar scientists…and Arctic terns) have come to find such a commute pretty standard fare. Yet for an Antarctic newbie like myself, this level of perpetual motion left me feeling as though we had traveled to the bottom of the earth. Fittingly, we’ve ended up just there. A mere 30+ hours in the air has landed us at McMurdo Station, Antarctica.

Route Boston to McMurdo

But let’s backup for a moment.

Up until leaving New Zealand, our travels had all been standard commercial airlines. But for NSF funded projects such as the McMurdo LTER in which we’re participating, travel to the field happens on Air National Guard LC-130 cargo planes. So in preparation for this we all spend a day in Christchurch, NZ at the CDC (Clothing Distribution Center), where we are briefed with orientation videos, our computers are security checked, and we are outfitted with our polar gear.

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When we arrive at the CDC, we step into a large changing room where two orange duffle bags sit waiting for each person.

Gradually we pull out piece after piece of cold weather clothing. This ranges from giant puffy jackets and white rubber “bunny boots”, to silky long underwear and wool socks. The warehouse here is impressive and fully stocked.

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After all of our gear preparation is finished, Ruth and I take to the streets of Christchurch. Walking downtown it’s immediately evident that the city is still in recovery, even three years after their devastating earthquake. Piles of rubble are fenced off on city blocks, and large open spaces are left where hotels, restaurants, and apartment complexes used to stand.

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We walk through the city’s new “shipping container-chic” shopping centers, where fallen buildings have bee replaced by funky colored shipping containers selling street food, clothing, books, and jewelry.

In the evening, we walked to nearby Hagley Park to bring in the New Year. Crowds of people sat in the grass swaying to the sounds of local cover-bands singing Jonny Cash in Kiwi accents. Finally, per New Zealand tradition, we were all enchanted by the Arch Wizard of Canterbury as he casts an explosive (fireworks were involved…) spell on the crowd for coming year.

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The Arch Wizard is projected onto a giant screen as he casts his spell.

 

The next day, we go back to the CDC to don our polar gear, check our bags, and get briefed by the ANG on flight to the ice. It’s a toasty ride for those 8 hours to McMurdo, as we have to wear our big red jackets, snow pants, and bunny boots on the plane.20150101_112747

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Soon enough, we feel the plane glide onto the ice and we step out into a blindingly white world. The team has officially arrived in Antarctica.

Photo credit: Ruth Heindel

Stay tuned for updates on the science we are now preparing to do!

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Today we hiked from Pangboche to Periche, only a 2 hour hike.  Yesterday we hiked about 5 hours down to the valley floor, crossed the river, and then came back up, gaining only 200 m net elevation. From now on we’re going up so taking care to build in a little rest time. The plan is to acclimatize here in Pheriche (4240m) overnight then hike up to Pyramid (4970 m), the worlds highest meteorological station (I think). Well spend two nights there acclimatizing and then head to the Changri Nup base camp and start the data collection!

For reference, here’s the last part of our trek in. You can see Khumjung where we were 2 nights ago, Pangboche where we were last night, and Pheriche where I’m writing from. Pyramid Station is also labeled, near the ring finger in this pic.

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Yesterday on the trail I saw one of my boxes of scientific gear go by! This box contains a 400 MHz ground penetrating radar as well as a few other instruments. Masters student Josh Maurer is on the left.

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Pheriche in the distance

Pheriche in the distance

On the way to Pheriche this morning

On the way to Pheriche this morning

I’ve been enjoying the hike in (very different from taking a plane or helicopter to my field sites) and am looking forward to our day at Pyramid when we’ll be programming temperature sensors, etc. for the field.
Prof. Mike Dorais (BYU geology prof) has been teaching us about the geology along the way. The first night we all sat around a geologic map of Nepal and learned about how the Himalayas formed (and why there’s a yellow stripe of sedimentary rock at the top of Everest!). And he’s pointed out a few neat rocks along the trail.

I’ve enjoyed hiking and socializing with such accomplished scientists on the trek in and have been having very enlightening conversations about the importance of collaboration in science, why different people chose careers in glaciology, what the other grad students see as being next for them, etc.  Thanks for reading! Will update again when possible!

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