Fig. 6
The range of SOC sequestration rates varied greatly from -1.256 (under ST) to 5.320 (under NT) Mg C ha-1yr-1 (Fig. 6). The mean value of SOC sequestration rate under NT, RT, and ST was 0.953, 0.099, and 0.101 Mg C ha-1 yr-1, respectively. The SOC sequestration rate under NT was significantly higher than that under RT (P < 0.05), although there was non-significant difference between NT and ST or ST and RT. Based on all the data under conservation tillage measures, the mean value of SOC sequestration rates is 0.658 Mg C ha-1 yr-1, indicating that conservation tillage can enhance SOC sequestration in NEC.
3.3. Relationships between Yield and SOC