The root weight was lower, and the root length was longer in C1 than in
C2 particularly at the deeper depth of the plough layer under ST, suggesting the impedance of root growth
due to higher sinkage and penetration resistances. SOC concentration was weakly correlated with the
sinkage and penetration resistances and the tensile strength after the 1st drainage, but not with the
tensile strength after the 2nd and 3rd drainages. In conclusion, rice straw incorporation is important to
maintain SOC and then improve soil puddlability and the recovery of pore structure during the rice
growth period.