Tillage Intensity and Tillage-Induced CO2Loss

Abstract

Field experiments were done to measure the effect of different primary tillage methods on the CO2 flux from soil and to evaluate the effect of conservation tillage tools on short-term CO2 emissions. The experiments were conducted on a clay loam soil winter wheat field and a corn field. The three tillage treatments included stubble mulching (disc harrow, mulch tiller, chisel plough), primary tillage (disc harrow, moldboard plough, and chisel plough) and secondary tillage (combined seedbed maker). The control treatment was no-till with soil and residues left by the harvester. The CO2 flux from the tilled soil surface was measured by a portable closed-chamber tester. Moldboard ploughing produced the roughest soil surface and the highest initial CO2 flux and maintained the highest flux throughout the experiment. The moldboard ploughing caused higher CO2 loss than less intensive tillage such as chisel ploughing, mulch cultivating, or disc harrowing. Primary tillage caused higher CO2 emission in the fall than s...