To explore the influence of dry-wet cycles on soil aggregate stability in Southwest China

an experiment was conducted in the Jinyun mountain in Chongqing. A typical yellow soil in cultivated land was taken as the research object. With four groups of aggregates of different particle sizes (1-2

2-3

3-5

and 5-7 mm)

seven dry-wet cycle processes (1

2

3

5

7

10

and 15 times) under four antecedent moisture levels (air dried

10%

15%

and 20%) were simulated. The stability?features of soil aggregates after dry-wet cycles under different broken mechanisms were discussed with the Le Bissonnais method. The results showed that: (1) Fast wetting (FW) had the most serious damage on soil aggregate stability

and there was a significant difference between FW and the other two broken mechanisms (slow wetting (SW) and stirring (ST)). (2) Compared with large-size aggregates

the stability of small-size aggregates was higher. (3) The destructive effect of dry-wet cycles on aggregate stability was obvious

and the extent of the damage was different under different antecedent moisture levels. (4) The dry-wet cycle processes mainly affected the stability of aggregates by affecting the percentage of >2 mm aggregate fragmentation. These results had an important reference value for the study of soil erosion mechanisms in Southwest China.