Effects of Amendment Type, Application Time and Rate on Soil Acidity Characteristic Index

Soil amendments can reduce soil acidity in acidic soils, but the improvement effect of different amendments application methods is quite different. In order to clarify the application method of acid soil amendment and obtain the best improvement effect, a field experiment with 3 factors (amendment type, the application time, and the application amount) and 2 levels was conducted to study the effects of amendment type, application time and application rate on soil acidity characteristic index. The application of the amendment can significantly increase the soil pH and base saturation (BS), and the soil exchangeable hydrogen (EH+), exchangeable aluminum (EAl3+) and hydrolytic acidity (HA) are significantly reduced, but the improvement effect of the amendment on these indicators will decrease with time; on the 120th day after tobacco transplanting, compared with CK (control check), soil pH and BS treated with the amendments increased by 7.50%similar to 10.38%, 6.46%similar to 12.56%, and the soil EH+, EAl3+ and HA decreased by 43.21%similar to 46.91%, 45.45%similar to 55.54%, 22.48 degrees similar to 59.69%, respectively; both soil amendments increased the soil cation exchangeable capacity (CEC) only at the early stage of application. The application of the amendment has the greatest influence on the soil pH, EH+ , EAl3+, HA, CEC and BS on the 30th day after transplanting the tobacco; the type of amendments has the greatest influence on soil HA, the application time has the greatest influence on soil pH, EH+ , EAl3+, and CEC, the interaction of types and rate of amendments has the greatest impact on soil BS. For acid tobacco-planting soil, the application of 1500 kg.hm(-2) lime when the mulch removed and soil hilled has the largest impact on soil acidity index, and the improvement effect is the best.