ABSTRACT
This chapter focuses on a study to quantify the methane (CH4) consumption rates in subarctic agricultural soils and determines CH4 consumption rates in soils from fertilized and unfertilized grass fields, at different soil depths and under different temperature regimes. Two sites near Fairbanks, Alaska were selected based on their different nitrogen (N) fertilization but similar plant history. One site was on Fairbanks silt loam and the other site was on Tanana silt loam. For the laboratory studies, soil cores, 50 cm in length were collected in plastic tubes lining the soil corer. Rates of CH4, oxidation were calculated from the soil mass, jar headspace volume, specific volume of CH4, and decrease in CH4 concentration. Methane analysis was performed within 24 hr after sampling, following the procedure described by Cochran. Methane uptake rates in the first week of July, were highest in soils from the top 0–30 cm depth in both hill and flat sites.
