pH、温度和水土比对酸性土壤溶液中铝离子形态分布的影响

Effect of pH, Temperature and Ratios or Water to Soil on Distribution of Al^(3+) Species in Acid Soil Solutions

溶液中Al3+、Al-F和有机络合态铝（Al-OM的浓度随pH降低而增加，Al3+在总单核铝中所占比例随pH的降低而增加，而Al-F络合物呈相反的变化趋势.土壤中铝的溶解度与土壤中铝氧化物的结晶形态有关，处于较高纬度地区的土壤，由于铝氧化物的结晶形态较差，在相同pH下，其铝的溶解度较大.土壤溶液中有机络合态铝的浓度随温度升高而增加，在pH不变的情况下，土壤中无机铝的溶解量随温度降低而增加.随水土比增加，土壤溶液中Al3+、Al-F络合物和Al-OM浓度减小，但按每kg土计算的铝溶解量随水土比的增加而增加.

The concentrations of Al3+, Al-F complexes and Al-OM increased with the decrease in pH. The proportion of Al3+ to total monomeric Al increased with the decrease in pH, but that of Al-F complexes increased with the increase in pH. The Al solubility in soils was related to crystalline forms of Al oxides. The Al solubility in soils in higher latitude zone was higher than that in low latitude zone at the same pH due to the less orderly arrangement of crystalline forms of Al oxides. The concentration of Al-OM in soil solution increased with the rise in temperature, and at the constant pH, the concentrations of monomeric inorganic Al increased with the drop in temperature. The concentrations of Al3+, Al-F complexes and Al-OM decreased with the increase in ratios of water to soil, but amount or dissolved Al expressed as mg/kg soil increased with the increase in ratios of water to soil.