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 2015
• Subjects: Aquatic; Digital repeat photography; Drained thaw lake basins; Methane; Nutrients; Wetlands; Climate; Environmental Indicators and Impact Assessment; Environmental Sciences; Arctic; Barrow Peninsula; Barrow; Climate change; permafrost; Tundra; Alaska
• Online Access: https://scholarworks.utep.edu/open_etd/1198; https://scholarworks.utep.edu/cgi/viewcontent.cgi?article=2197&context=open_etd

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. Specifically, this study aims to: * Assess decadal time scale changes in surface hydrology of tundra wetland ponds and its relationship with landscape geomorphological evolution. * Determine decadal time scale changes in methane emissions through modeling of environmental drivers of methane efflux from aquatic vegetation. * Develop and evaluate novel near-surface remote sensing tools for monitoring phenology and productivity of Arctic aquatic macrophytes. * Investigate the impacts of nutrient enrichment on Arctic aquatic plant productivity and spectral properties. 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 ...