Site characteristics and plant community development following partial gravel removal in an arctic oilfield

Abstract

This paper describes the results of a revegetation experiment involving partial removal of gravel fill followed by various revegetation treatments on five sites in the Prudhoe Bay Oilfield on Alaska's Arctic Coastal Plain. Gravel fill was removed to a residual thickness of approximately 25 cm. Revegetation treatments were transplanted tundra plugs and fertilizer; seeding with indigenous graminoids and fertilizer; seeding with native-grass cultivars and fertilizer; fertilizer only; and no treatment. We monitored surface stability, soil characteristics, and vegetation response from 1990 to 2003. Thaw settlement of 17-40 cm occurred over most areas (with >1 m over areas with ice wedges) between 1990 and 1997; sites had mostly stabilized by 2003. Soil properties important for plant growth generally were poor. The establishment of vegetation dominated by indigenous species was similar when adding only fertilizer as compared to also adding plant materials. Although total live vascular cover was similar among fertilized, tundra-plug transplant, and indigenous graminoid seed treatments (26.1-38.3%), species richness was highest for the indigenous graminoid seed and tundra-plug transplant treatments. The results from this study will drive decisions about planting and fertilization schemes for future North Slope rehabilitation projects. © 2006 Regents of the University of Colorado.