3 December 2010

page last updated: 2 December 2010

Water Tracks in the Foothills of the Brooks Range

Erin Trochim

Water tracks on the hillslope connecting to the Upper Kuparuk river in the valley below

Credit: Erin Trochim

Abstract

In the northern foothills of the Brooks Range in the Alaskan Arctic there are thousands of small headwater drainage basins which are underlain by continuous permafrost. Assessing the hydrological cycle in these areas is very difficult because only two basins, the Imnavait and Upper Kuparuk, which are adjacent to the Dalton Highway, have long-term discharge and climatology records. Knowledge of the hydrological cycle is important for assessment of fish and wildlife habitat, climate variability and potential infrastructure and economic development. Quantifying the drainage network is a first step to understanding the processes which control water movement in these headwater catchments. In the foothills the landscape is dissected by water tracks, linear-curvilinear features which move the water from the slopes to the streams via saturated channels which contain enhanced soil moisture and nutrient properties in contrast to their surrounding areas. Field investigations and remote sensing techniques have been used to investigate the connections between water movement, soil properties, permafrost and vegetation within water tracks. This data was used to classify water tracks into a conceptual model and illustrate the relationships between hydrology, ecology and periglacial processes in water tracks.