In this study

a series of field microfield experiments were set to explore the effect of amendments on aggregates composition and organic carbon distribution in reclaimed soil. Peat

humic acid and vermiculite as amendments were added to the soil (0-20 cm) at the weight ratios of 1%

3% and 5%. Soil aggregates composition

total organic carbon

organic carbon distribution in each fraction aggregates

soil infrared spectrum characteristics were analyzed. The results showed that soil mainly composed by > 5 mm mechanical stabilized aggregates

and the content of > 5 mm aggregates increased with the increase of the proportion of peat and humic acid application in all treatment

and the MWD in all treatments were higher than CK. The effect of 5% humic acid application was the best for improving the content of > 5 mm mechanical stabilized aggregates

and the proportion of > 5 mm mechanical stabilized aggregates reached to 60.03% in the sixth month. However

compared with CK

the proportion of > 5 mm mechanical stabilized aggregates decreased after vermiculite was used. After the application of amendments

soil mainly composed by < 0.053 mm water stabilized aggregates

but its content all decreased with the increasing amounts of amendments. Peat and humic acid could increase the content of total organic carbon and the resistance to erosion and the stability of aggregates for reclaimed soil. However

the organic carbon content decreased after vermiculite was used. For all peat

humic acid and vermiculite treatments

the content of organic carbon in > 5 mm aggregates were the highest

followed by 0.053 ~ 0.25 mm aggregates

and the content of organic carbon in < 0.053 mm aggregates were the lowest. The organic carbon contribution in > 5 mm aggregates were the highest. The organic carbon contribution rate of > 5 mm aggregates were higher than 50%. The organic carbon contribution rate of < 0.053 mm aggregates were the lowest

and accounted for 0.63% ~ 2.82% in all of peat and humic acid treatments. The soil infrared spectroscopy characteristic showed that humic acid increased the content of polysaccharides in soil. There were many hydroxyl in polysaccharides and they could form hydrogen bonds with the oxygen atoms on the crystal surface of clay minerals

which can agglomerate the soil particles.