Early effects of helicopter liming on soil and vegetation in two acidified forest stands in Nova Scotia, Canada

Abstract

Increased fossil fuel burning in the 1900’s caused high levels of acid deposition in northeastern North America. Acid deposition depletes soil base cations and increases toxic aluminum concentrations. Base cation depletion impairs forest growth, regeneration, and ecosystem health. Despite decreases in acid deposition, little to no improvement in soil base cation concentrations over the last 30 years has been reported in Nova Scotia. This study conducted a terrestrial liming trial at the Otter Ponds Demonstration Forest in Mooseland, NS, where 10 t ha-1 of dolomitic limestone was deposited via helicopter over mature acidified forests and assessed one year after liming. The results show that despite a non-uniform distribution of lime, soil Ca2+, Mg2+, percent base saturation, and pH increased, and total acidity decreased in the forest floor. The initial response indicates that helicopter liming can promote recovery from soil acidification and increase the value of currently acidified forests in NS.