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土壤团聚体的稳定性常被作为土壤侵蚀的敏感指标。为了揭示三峡库区消落带土壤团聚体受破坏的主要机制，选取三峡库区童庄河消落带不同海拔梯度的土壤，以从未淹没的样地作为对照，采用 Le Bissommais 的快速湿润法（fast wetting， FW）和慢速湿润法（slow wetting， SW）模拟研究消落带水位消涨对土壤团聚体稳定性和土壤抗侵蚀能力的影响。2 种处理下的土壤水稳性团聚体平均质量直径（MWD）均是中等淹没区域（155～165 m）最大，淹没持续时间较长区域（145～155 m）最小，从未淹没的对照样地（175 m 以上）和淹没时间较短区域（165～175 m）之间处于中间状态，而 K 值却是淹没持续时间较长区域（145～155 m）最大，中等淹没区域（155～165 m）最小。这意味着消落带淹没持续时间较长区域受淹水扰动相对最强烈，土壤水稳性结构最差，土壤可蚀性最强。比较 FW 和 SW2 种处理下的土壤团聚体粒径分布，FW 处理后，不同颗粒级的团聚体较为分散，处理后土壤水稳性团聚体以＜1 mm 为主；SW 处理后土壤水稳性团聚体主要以＞2 mm 团聚体为主，这意味着三峡库区消落带水位快速升降可能对土壤团聚体的结构破坏较大，其破坏的主要机制是土壤孔隙中的气泡爆破产生的消散作用。
Soil aggregate stability is often used as a sensitive indicator of soil erosion. In order to reveal the main mechanism of the destruction of soil aggregates in the hydro-fluctuation belt of the Three Gorges Reservoir Area, the soil with different altitudes in the Tong Zhuanghe hydro-fluctuation zone of the Three Gorges Reservoir Area was selected to take the non-submerged plots as control. The rapid wetting method of Le Bissommais Fast wetting (FW) and slow wetting (SW) simulations were performed to study the effects of fluctuating water level in the ebb and flow belt on soil aggregate stability and soil erosion resistance. The average mass diameter (MWD) of soil water-stable aggregates under the two treatments were the highest in medium submerged areas (155-165 m) and the lowest in submerged ones (145-155 m) (175-175 m above sea level) and the submerged area (165-175 m), while the K value was the largest in the submerged area (145-155 m) and the middle submerged area (155-165 m m) the smallest. This means that the disturbance zone with relatively long duration of submergence was the strongest, the water-stable structure was the worst, and the soil was the most erodible. The particle size distribution of soil aggregates under FW and SW2 treatments was compared. After FW treatment, the aggregates with different particle size were dispersed, and the aggregates of soil water-stable aggregates were mainly <1 mm after SW treatment. The soil water stability Aggregates are dominated by> 2 mm aggregates, which means that the rapid rise and fall of the water level in the hydro-fluctuation zone of the Three Gorges Reservoir might cause greater damage to the soil aggregates. The main mechanism of this destruction is dissipation of air bubbles in the soil pores effect.