Thursday, October 11, 2012, 4:30PM - 5:30PM
RL-1 room 269
Join us for a slideshow from the 2011-2012 Stream Team Field Season in the McMurdo Dry Valleys Long Term Ecological Research Site.
The McMurdo Dry Valleys are a cold polar desert and together make up the largest ice-free area on the continent. They are on the shore of McMurdo Sound, 2,200 miles south of New Zealand and about 50 miles northwest of McMurdo Station. This research site has been monitoring the Dry Valleys since the early 1990s and includes not only the streams, but also the lakes, glaciers, soils and weather/atmospheric influences. The goal is to understand ecological connectivity between systems. There are 26 long-term ecological research sites in the United States and 12 more across the world. This one represents a polar end member, enabling the study of ecology at extreme environmental limits. As members of the Stream Team, we measure stream-flow throughout the duration of the flow season and take water samples for chemical analysis of factors like nutrients and dissolved organic carbon, which can help explain some of the physical processes occurring in the streams. There are more than 16 permanent stream gauges, which we visit about once a week, and 10 un-gauged streams which are also monitored. It can make for busy weeks when all the streams are flowing. As water flows from the glaciers, nutrient exchange with the soil, as in the hyporheic zone, as well as with algal mats, affects water quality entering the lakes. The lakes are perennially covered with ice and have no outflow. Thus, as the primary nutrient sources, the streams influence the diverse biogeochemical environments unique to each lake. Again, this will mainly be a slideshow, with time for questions about the science as well!