Application of bentonite can enhance accumulation of HA in the fraction of close and steady combined humus, and the HA/FA ratio.

• 施用膨润土促进了紧结态和稳结态腐殖质中HA的积累，提高了HA/FA比。胡敏酸红外吸收光谱表明，膨润土能使其脂肪族物质增多、芳化度降低。