To confirm the effects of mulching on soil aggregate characteristics

the distribution of micro-aggregate and macro-aggregate and also stoichiometry of macro-aggregate were explored. In the 20—40 cm soil layer mulched with manure

the percentage of the 10～150 μm micro-aggregate was 84.5%

which was 3.7% higher than control

while the percentages of the 1～5 mm macro-aggregate and the ＞5 mm macro-aggregate were 47.74% and 33.04%

respectively

and the corresponding changes were 56.8% and 49.5% compared with control. In the 0—20 cm soil layer

total N

total P

TOC of all soil aggregates mulched with manure were

on average

1.04

0.81

and 14.39 g/kg

respectively

which were 2.9

5.1

1.4 times that measured in control

and the corresponding values under treatment with wood chips were 0.61

0.32

and 7.42 g/kg

respectively

which were 1.7

1.0

2.3 times that measured in control. The C/N

C/P

N/P ranges of soil aggregate mulched with manure were 8.29～22.65

4.45～27.18

and 0.44～1.89

respectively

and the ranges of that of wood chips were 4.09～29.60

5.32～59.88

and 1.04～3.29

respectively

while the control were 4.71～12.24

10.08～25.42

and 0.86～3.10

respectively. In all

mulching promotes the percentage of the 1～5 mm macro-aggregate

and weaken the ＞5 mm macro-aggregate and micro-aggregate. Moreover

the total N

P

TOC and C/N

C/P of the soil aggregates were all increased in degree with muchling.