Erosion Control and Restoration of a Sand Dune on the Colville River Delta, Northern Alaska

Abstract

We undertook a restoration project on 1.5 ha of a vegetated sand dune leveled in order to build an airstrip for an oilfield on the Arctic Coastal Plain of northern Alaska. We seeded Nortran tufted hairgrass (Deschampsia caespitosa), a relatively non-palatable native grass, to rapidly develop a ground cover that would stabilize the sandy substrate but not attract wildlife. We transplanted 4,400 willow (Salix spp.) cuttings and 11,500 sprigs of American dunegrass (Leymus mollis) and seeded two forb species to increase species diversity and the vertical structure of the plant canopy. Total live cover increased to 73.9% after three years, limiting wind erosion to less than 5% of the treated area. The seeded and transplanted grasses and the naturally colonizing wideleaf polargrass (Arctagrostis latifolia) accounted for most (66.2%) of the plant cover. Survivorship of transplanted willows after 3 years was 26–34%, and we observed annual incremental increases in cover of willows, seeded forbs, and other naturally colonizing species. We identified 31 vascular plant species in the treated area after three years. Of these, 15 were present before the airstrip was constructed, and 19 occurred in natural sand dune ecosystems in the region. These results demonstrated the feasibility of cultivating locally collected native plant materials to control erosion of a disturbed sand dune in the Arctic and to initiate a longer-term process of ecological restoration.