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.
Posts
