The macro-aggregates content (R0.25)

mean weight diameter (MWD)

geometric mean diameter (GMD)

the percentage of aggregate destruction (PAD) and contribution rates of aggregates to organic carbon (F)

which were selected to analyze the effects of different age of alpine desertification land planted branchy tamarisk on soil aggregates stability and organic carbon distribution in northwestern Sichuan. The results showed that soil mechanical stability aggregates and water-stable aggregates were mainly composed of micro-aggregates (<0.25 mm) in different restoration years of branchy tamarisk restoration pattern. With the increase of recovery period

soil surface (0—20 cm) >2

0.5~2 mm aggregates increased significantly

and the ranking of R0.25

MWD and GMD from low to high was:0 year <5 years <10 years <15 years

while PAD presented opposite trends. The planting of branchy tamarisk caused a significant increase in soil organic carbon content in the surface layer (0—20 cm). With the increase of recovery period

organic carbon content of >2

0.5~2 mm aggregates increased significantly

and the contribution rates of >0.5 mm aggregates to soil organic carbon was 34%~60%. The effect of planting of branchy tamarisk to soil aggregates and organic carbon on sub-surface layer (20—40 cm) was not significant. The results indicated that soil aggregates stability and organic carbon can be used as the adaptable index of soil ecological restoration in northwestern Sichuan

and the planting of branchy tamarisk has an important effect on improvement of desertification soil.