Distribution of organic carbon fractions in soil aggregates in Chinese fir plantations with different stand ages

Ecological Processes

Table 8 Effects of aggregate sizes (> 2, 2–1, 1–0.25, and < 0.25 mm) and stand ages (0, 9, 17, and 26 years) on the soil mineralized organic carbon concentration in a chronosequence of Chinese fir plantations

Stand age (years)	Soil mineralized organic carbon concentration (mg kg⁻¹)				Effects
	> 2 mm	2–1 mm	1–0.25 mm	< 0.25 mm	Aggregate size (A), df = 3		Stand age (S), df = 3		A × S, df = 9
	> 2 mm	2–1 mm	1–0.25 mm	< 0.25 mm	F	P	F	P	F	P
0	73.88 ± 1.96 b	69.25 ± 4.63 c	123.13 ± 1.21 b	68.80 ± 2.80 c	7.524	0.001	35.533	< 0.0001	156.552	< 0.0001
9	90.68 ± 5.21 a	103.77 ± 2.51 a	132.55 ± 2.08 a	60.87 ± 1.37 d
17	97.72 ± 3.77 a	66.55 ± 2.48 c	54.82 ± 4.23 d	145.02 ± 0.91 a
26	87.30 ± 2.14 a	80.18 ± 3.64 b	71.62 ± 1.09 c	127.40 ± 3.54 b
Mean	97.19 ± 10.38 B	95.53 ± 10.01 B	79.94 ± 4.62 AB	87.40 ± 3.01 A

Data represent the average of 3 replicates ± standard errors. Different lowercase letters indicate significant differences among the different stand ages. Different capital letters indicate significant differences among the different aggregate sizes