PLS regression suggested that soil aluminum saturation(AlS) was the dominant factor affecting the Al_i/(Ca+Mg) molar ratio in soil A horizon.

• 偏最小二乘法(PLS)回归显示,土壤铝饱和度(A lS)是影响A层土壤水中A li/(Ca+Mg)摩尔比值的首要因素;