Wednesday, December 29, 2010

Fertilizing a Polar Desert

This week, Mike, Jenn and I have been working on one of the long-term experiments we're running in the dry valleys. This experiment investigates how the soil responds to nutrient fertilization. Like I mentioned yesterday, nutrients are important for organisms to grow and metabolize. Our experiment asks which nutrients are limiting to growth of soil organisms and how giving them extra nutrients influences soil processes (like nutrient cycling). The three of us have added nutrient treatments to our research plots. We added the three major elements that are important to life everywhere on the planet: carbon, nitrogen, and phosphorus. We do this by adding those nutrients dissolved in water. Every year we add more nutrients and measure the response.

To add the treatments to the plots, we have to bring a LOT of water to the field: 775 pounds of water! We do this at two different places. On Monday we did the plots near F6 where I have been living. Today, we did the plots at the other end of the valley, near Lake Bonney. We carry the solutions to the field in 35 ten-liter carboys, and then transfer 5.6 L at a time to pour jugs with sprinkle caps to be applied to the plots. There's a very specific technique that's important to use. In this video, Jenn and Mike are demonstrating the technique, working at two different parts of the plot at Lake Bonney. Jenn is in the distance sprinkling water over the plot through a plexiglass cone, which helps guide the water to the correct spot like a giant funnel. Mike is closer up preparing to pour by placing his cone in the correct spot.

It's a lot of heavy-lifting of water! And how do we carry all 35 of those carboys? Teamwork.

In the video, you can also see the clouds that were encroaching upon us while we worked. In one direction, skies are blue. In the other, there's nothing but a ceiling of clouds. Right now, I'm back at F6, and those clouds are hovering right over our hut! I hope they pass quickly, because tomorrow I'm scheduled to start the measurements on the plots to see how the organisms are responding. They are much more active when it's sunny and warmer out. Keep your fingers crossed for the return of beautiful weather!