Fertilizing and Seeding Oil-Damaged Arctic Tundra to Effect Vegetation Recovery

ABSTRACT. Vegetational recovery from an accidental oil spill on a wet tundra site at Prudhoe Bay, Alaska, was studied during six growing seasons. The spilled oil consisted of 22 ” API gravity, Prudhoe-Bay crude from which diesel and heating oil fractions had been removed by a topping process. Damages from the winter spill ranged from killing the moss layer and above-grounds parts of vascular plants to killing all the macroflora. Damage to the oil sensitive mosses persisted throughout the study even in lightly oiled areas. Test plots where commercial phosphorus fertilizers had been applied were an exception to this. Moss cover began re-establishing during the first growing season with phosphorus fertilization and continued to improve thereafter. Growth of sedges and grasses, not killed by the oil, was significantly enhanced by phosphorus fertilizations, even though oil persisted in the soil. Revegetation attempts in a barren area during the fourth growing season after the spill resulted in establishing Puccinellia borealis (alkaligrass) seedlings and mosses in phosphorus-fertilized plots. Neither nitrogen nor potassium fertilizers alone and combined with each other improved growth of either resident or seeded plant specie