Table 1 Masses of water-stable aggregates and macroaggregate fractions to 40 cm deep in the control treatment (CK), chemical fertilizer treatments (NPK and 2NPK), and combined manure and chemical fertilizer treatment (MNPK) (unit = %).

Treatment	Water stable aggregates			Macroaggergates			Density fractionation
Treatment	Macro	Free-m	Free-SC	cPOM	Inter-m	Inter-SC	fPOM	fiPOM	Intra-SC
0–10 cm
CK	50.8b	40.0a	8.0a	0.20c	24.2c	19.5c	0.052b	0.023b	23.4c
NPK	59.2b	34.6b	5.1b	0.26c	28.8ab	24.3b	0.058b	0.061b	28.4ab
2NPK	59.4b	34.0b	4.7b	0.41b	30.0a	23.6b	0.081a	0.068b	29.4a
MNPK	61.0a	32.1b	5.2b	0.80a	25.5bc	28.5a	0.084a	0.219a	24.7bc
10–20 cm
CK	67.5c	27.3a	4.0a	0.18a	40.3a	22.2c	0.025c	0.021b	39.8a
NPK	71.2b	23.6b	3.9a	0.23a	39.7a	26.1b	0.030bc	0.022b	39.2a
2NPK	73.1ab	23.2b	2.9a	0.21a	39.7a	27.1b	0.039b	0.036b	39.3a
MNPK	75.3a	20.2c	3.1a	0.24a	40.2a	30.1a	0.054a	0.095a	39.5a
20–40 cm
CK	71.4a	24.2a	3.7a	0.09a	48.4a	19.1b	0.015a	–	47.9a
NPK	72.6a	23.6a	3.4a	0.10a	46.2ab	20.9b	0.017a	0.037a	45.6ab
2NPK	72.4a	23.8a	2.9a	0.12a	44.5ab	22.2ab	0.016a	0.017b	44.1ab
MNPK	71.8a	24.2a	2.7a	0.12a	41.8b	25.5a	0.018a	0.038a	41.5b

Each value is the mean of three replicates. Different letters within the same column indicate the least significant difference values at the 0.05 level (LSD0.05) for the different treatments at the different depths.
Macro, free-m, and free-SC are macroaggregates (> 250 µm diameter), microaggregates (53–250 µm diameter), and silt plus clay (< 53 µm diameter), respectively. cPOM, inter-m, and inter-SC are coarse particulate organic matter (POM), microaggregates in macroaggregates, and silt–clay in macroaggregates, respectively. fPOM, fiPOM, and intra-SC are fine POM, fine intra-POM, and intra-silt–clay in inter-m, respectively. Inter-m is the sum of fPOM, fiPOM, and intra-SC. fiPOM was not detected at 20–40 cm deep.

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