Quantity and fate of root derived soil carbon produced after a growing season of canola, lentil, pea and wheat in Canadian prairies

摘要

Soil carbon (C) sequestration mitigates climate change and improves lands productivity. Root derived soil C during a growing season is the first step toward C sequestration. The goal of this work was to evaluate the quantity and fate of newly producedsoil organic carbon (SOC) captured at the end of a single growing season of canola, lentil, pea and wheat in Canadian Prairie soils. This study was conducted using intact soil cores from two Agriculture and Agri-food Canada Research Stations (Scott andSwift Current). The crop rotations selected at Scott were pea-wheat, canola-wheat and continuous wheat and at Swift Current were lentil-wheat and continuous wheat. Using hermetic plexiglass chambers in a greenhouse, the plants of the first rotation phasewere labelled with ~(13)CO_2 weekly for two hours over eight weeks. At the end of the growing season, the cores were broken and the amount of 13C present in the dissolved organic matter (DOM), the light organic matter fraction, and heavy organic matterfraction was evaluated.