PS 3-27
The effects of Permafrost thaw on long-term nutrient release into Arctic Tundra Ponds

Monday, August 11, 2014
Exhibit Hall, Sacramento Convention Center
Aracely Tellez, Biology, University of Texas at El Paso, El Paso, TX
Francisco R. Reyes Jr., Geological Sciences, University of Texas at El Paso, El Paso, TX
Vanessa L. Lougheed, Biology, University of Texas at El Paso, El Paso, TX
Background/Question/Methods

With warming in the Arctic, more nutrients are being released from thawing permafrost into Arctic aquatic ecosystems. The levels of nutrient release over time are largely unknown. With higher nutrient levels in Arctic ponds, microbial activity as well as lower trophic levels may be significantly altered. To examine long-term nutrient release from thawing permafrost, and the role of microbial activity in this release, permafrost cores collected from Barrow, Alaska were incubated for 8 weeks in a cold room at two different temperatures (7°C and 15°C) in beakers containing either DI water alone or DI and formaldehyde. Water samples were collected at 24, 48, 72, 168, 336, 672 and 1776 (8wks) to measure: total phosphorus (TP), total dissolved phosphorus (TDP), dissolved organic carbon (DOC) and total nitrogen (TN). 

Results/Conclusions

A continuous increase in nutrient release was observed for all measure parameters; however, the impact of microbial activity differed among nutrients. Cores where microbial activity was inhibited had larger amount of nitrogen release, but lower levels of phosphorus release. Understanding the release of nutrients from the permafrost over the long-term can help model nutrient concentrations that will be added to arctic freshwater ecosystems with climate warming.