Emissions of Dissolved Greenhouse Gases in the Subsurface Drainage from Different Tillage and Cropping Systems.

Greenhouse gas emissions (CO₂, N₂O and CH₄) from soils under agricultural management practices are closely associated with climate change effects. However, there is a lack of information on dissolved greenhouse gas emissions from the subsurface drainage, as compared with soil, under different management practices. The objective of our study was to measure the dynamics of dissolved greenhouse gas emissions from the agricultural subsurface drainage under different tillage and cropping systems. Subsurface drainage was collected over time, processed to displace dissolved greenhouse gases into free-state by using N₂ and analyzed for CO₂, CH₄ and N₂O, respectively using a gas chromatograph. Results showed that sub-surface drainage is a significant source of greenhouse gases as compared to soil.