Comparison of differences in the soil respiration rates and environmental factors under the different treatment conditions.

Rs, soil respiration rate (μmol·m-2·s-1); T-5, T-10, soil temperature (°C) at depths of 5 and 10 cm; W, mean soil moisture of the 0–50 cm layer (%). The same lowercase letters in the columns indicate that differences among the indexes were not significant (P > 0.05) for the different months in the same treatment. The same capital letters in the rows indicate that differences among the indices were not significant at P > 0.05 for the different treatments in the same month.