GREENHOUSE GAS EMISSIONS FOLLOWING CONVERSION OF A RECLAIMED MINESOIL TO BIOENERGY CROP PRODUCTION

Authors

Jose G. Guzman, South Dakota State UniversityFollow
David Ussiri, Ohio State University
Rattan Lal, Ohio State University

Document Type

Article

Date of this Version

2017

Citation

Land Degrad. Develop. (2017), DOI: 10.1002/ldr.2808.

Comments

U.S. government work.

Abstract

This study provides a comparative assessment of greenhouse gas (GHG) emissions when converting a reclaimed minesoil that was previously under meadow to miscanthus (Miscanthus × giganteus) and maize (Zea mays L.) land uses in Ohio, USA. Additionally, effluent from an anaerobic digester at rates of 0, 75, 150, and 225 kg N ha^-1 rates was also assessed for C and nutrient fertilization. Results from the study show that land use conversion to maize had the highest net release of GHG equivalent of 6·6 Mg CO_2equ ha^-1 y^-1, on average, across effluent application rates. Under miscanthus land use with no and high effluent application rates, net GHG equivalent on average was 4·3 Mg CO_2equ ha^-1 y^-1, which was larger when compared with that under the meadow land use (1·6 Mg CO_2equ ha^-1 y^-1). Miscanthus land use under medium rates of effluent application had similar net GHG equivalent (7·1 Mg CO_2equ ha^-1 y^-1) to the maize land use. The application of effluent did increase CO₂–C and N₂O–N emissions; but increases in above-ground–below-ground biomass production (1·6 Mg C ha^-1) in the meadow land use and C input from effluent retained in the soil in the miscanthus and maize land uses offset most of the effluent-induced GHG equivalent emissions. Contribution of cumulative N₂O–N to GHG equivalent emissions in general was 11% when no effluent was applied and 22% when effluent was applied across land uses. Findings from this study show that land use changes from antecedent meadow to maize and miscanthus during the first year of establishment would result in net increase of GHG emissions.