A Half-Century of Biophysical Change in Polygonised Tundra on the Coastal Plain of Northern Alaska.

Polygonized tundra landscapes are widespread in the Arctic. Within these landscapes, there is a tight coupling between surface microtopography, surface hydrology, vegetation, energy balance, and permafrost dynamics. A change in any one of these elements appears to cause cascading ecosystem structural and functional change. Models suggest such change could impact various elements of the Earth System. To date, few studies have examined the interaction between the biophysical elements controlling ecosystem structure and function in polygonized landscapes over decade to half century time scales. Nonetheless, there is a well-recognized urgency for advancing knowledge in this area.

By rescuing and resampling a historic research site established in the early 1970's during the International Biological Programme (IBP) near Utqiaġvik (formerly known as Barrow), Alaska, this Masters project is documenting how the vegetation cover, surface hydrology, and microtopography of this fragile polygonized tundra landscape has changed over the last 45 years. Observing and measuring these changes in small-scale transects can provide a larger insight into how landscape dynamics work. Resampling efforts have utilized the same sampling approaches first employed at the site and others that utilize modern technologies.

Interpretation and discussion of results are focused on elements critical to the structure and function of polygonized tundra landscapes; preliminary analyses on active layer depth numbers show the most variation at ice-wedge features, which is known to have a direct impact in further defining the polygonal surface pattern. With this research, we continue to collect valuable long-term data that will continue to provide irreplaceable information for the next 45 years of polygonized tundra research in Utqiaġvik, Alaska.