Following the fate of 13C-labeled lentil, wheat, canola, and pea in two Chernozemic soils
Restoring carbon (C) into the soil is fundamental to improve soil quality, to increase agronomic productivity, to mitigate greenhouse gas emissions and to enhance several ecosystem services. The objectives of this study were to 1) determine the quantity and the fate of C captured during a single growing season of four simple crop rotations in the prairies and 2) evaluate the quantity and fate of those original residues after a second growing season. To track the progress of C into the different soil organic matter (SOM) pools; plants were grown in intact soil cores and pulse labeled with 13C in hermetic chambers. Results indicated that, at the end of the second growing season (approximately one year after the 13C enrichment), lentil and pea had more new soil C remaining in the soil than canola or wheat. Also at the end of the second growing season, it was found that the roots residues had producer a slightly greater amount of new soil C than the shoots residues. We concluded that 13C-enriched plant material is a versatile and powerful tool to study the C cycle. Longer-term studies with isotopic C residues are required to determine if the trends we observed are temporal or permanent.
soil density fractionation, root and shoot carbon mineralization
Soils and Crops Workshop