Impacts of direct seeding into mulch on the CO2 mitigation
¹UMR G-EAU Irstea, BP 5095, 34196 Montpellier Cedex 05 France 2University of Guilan, P.O. Box 41635-1314, Rasht, Iran *Correspondence: mohammad.khaledian@irstea.fr
Abstract:
The development of agricultural systems with low energy input could help to reduce agricultural greenhouse gas emissions. Tillage consumes nearby 50% of the direct energy in a conventional tillage system (CT). Current agricultural policies seek to promote crop production systems that minimize fossil energy input for a high level of output. One possible solution can be conservation tillage, in which tillage will be reduced or even completely eliminated, such as direct seeding into mulch (DSM). Conservation tillage can both reduce diesel consumption and sequestrate C into soil, resulting in CO2 mitigation. The present study assessed the impact of DSM on CO2 mitigation compared with CT. An experimental study has been carried out at Lavalette experimental station in Montpellier in south-east France. The diesel consumption for field operations was measured in both DSM and CT. Soil C concentration was also measured. CO2 emission was calculated considering CO2 emission from diesel combustion and organic carbon variations in soil during the field trial. The results showed that using DSM resulted in less diesel consumption compared with CT (about 50%). Furthermore, DSM increased C content of soil (1,671 kg. ha-1 year-1). The consequence of these two positive impacts of DSM resulted in considerable CO2 mitigation.
Key words:
CO2 emission, conventional tillage, direct seeding into mulch