Monitoring and understanding decadal scale changes in hydrology, productivity and carbon balance in Arctic tundra ponds

• Main Author: Andresen, Christian Gerardo
• Format: Text
• Language: English
• Published: ScholarWorks@UTEP 2014
• Subjects: Climate Change|Environmental science; Arctic; Barrow Peninsula; Arctophila fulva; Barrow; Carex aquatilis; Climate change; permafrost; Tundra; Alaska
• Online Access: https://scholarworks.utep.edu/dissertations/AAI3682449

The Arctic is known for containing large stocks of soil organic carbon, which exists frozen in permafrost in a greenhouse inert state. With predicted future warming in these high northern latitudes, the mobilization of stored soil organic carbon and release to the atmosphere may increase and induce further positive climatic feedbacks. Previous studies have shown that Arctic wetlands and ponds cover a large percentage of the Arctic Coastal Plain and contribute large amounts of carbon to the atmosphere; however, it remains largely unknown how these systems are responding to a warming climate and how this change will impact regional carbon budgets. Therefore, it is of urgent interest to better assess and monitor the effects of climate change on Arctic wetlands and their role in the fate and transport of carbon to the atmosphere. The overall focus of this dissertation is to identify decade time scale changes in the structure and function of Arctic tundra ponds, to understand how these changes are driven by warming and nutrient enrichment, and to advance new technologies to remotely track environmental change. Our study was carried out on the Arctic coastal plain, more specifically on the Barrow Peninsula, Alaska. This region is underlain by continuous permafrost and dominated by drained thaw lake basins containing numerous wetland ponds. The comparison of historical aerial imagery from 1948 to modern high resolution satellite imagery revealed a net decrease in area and number of ponds. This contradicts geomorphological succession processes in the Arctic coastal plain and provides evidence that climate change can reverse millennial-scale processes affecting landscape evolution and surface energy balance for this region. During the summers of 2010-2013, re-sampling of historical research sites established in the 1970's demonstrated a deepening of the active layer and an increase in aboveground biomass and cover of the dominant aquatic plants Carex aquatilis and Arctophila fulva. This is attributed to an increase in ...