The effect of tillage methods on soil physical properties and maize yield in Eastern Inner Mongolia

Abstract

Long-term shallow tillage has degraded the soil structure, which has increased the difficulty of increasing the yield of maize (Zea mays L.) in Eastern Inner Mongolia. The aim of this study was to select optimal tillage practices to gain high maize yield in this region. The experiment included farm shallow rotary tillage (FR), strip cultivation (SC), subsoiling (SS), deep ploughing (DP) and no-tillage (NT) in maize fields in Chifeng, Tongliao, Xingan and Hulun Buir, Eastern Inner Mongolia. The effects of tillage practices on soil physical properties and maize yield were studied from 2018 to 2020. The results showed that bulk densities of SC, SS and DP were all lower than that of FR at each site. In contrast, the soil aeration porosity was higher from SC, SS and DP compared with FR at some soil depths. The water contents of DP and SS at Tongliao and Xingan and no-tillage (NT) at Hulun Buir were higher than that of FR. Correlation analysis showed favorable soil conditions promoted maize grain yield. The yields of maize that used SC and DP were 4.3% and 10.96% significantly higher in Chifeng, respectively, while the yields in Xingan were 15.93% and 18.22% significantly higher than those of FR, respectively. SS and DP resulted in a higher yield in Tongliao, and the other tillage methods had a higher yield in Hulun Buir compared with FR, whereas, the yield of NT was less than that of FR in Chifeng and Tongliao. Based on the physical properties of the soil and yield of maize, SC and DP are the optimal tillage practice for Chifeng and Xingan; SS and DP are optimal for Tongliao and Hulun Buir.