Three methods to estimate N2O fluxes as impacted by agricultural management

Abstract

This study examines three methods of evaluating N2O flux and accumulation in soil profile over a growing season under three soil management regimes (fallow, fallow with manure addition and cropped to alfalfa). Estimates of N2O flux were made based on measured soil atmosphere concentration gradients in the top 15 cm and compared to flux estimates based on ex situ cores and micro-meteorological measurements made in parallel studies. All methods indicated strong seasonal trends relating to precipitation events. The amounts of N2O accumulating the profile decreased in the order alfalfa < fallow