Table 1.
Characteristics of the soil sampled in September 1989.
Figure 1.
Effect of long–term applications of compost and fertilizer NPK on the mass proportion of aggregates in soil.
Vertical bars indicate the standard error of the means (n = 4). Different letters denote significant differences between aggregates in the same treatment (a, b, c, d, e) and between treatments with the same aggregate (x, y, z) at P<0.05.
Table 2.
Effect of long–term applications of compost and fertilizer NPK on organic C concentrations (g C kg–1 aggregate) in aggregates.
Figure 2.
Effect of long–term applications of fertilizer NPK and compost on the proportions of pore volumes of different diameter (a) and effective diffusion coefficient of oxygen (b) in the soil.
Vertical bars indicate the standard error of the means (n = 4). Different lowercase letters denote significant differences between treatments at P<0.05.
Figure 3.
Effect of long–term applications of fertilizer NPK and compost on concentrations (nmol g–1 aggregate) of bacterial, fungal, actinobacterial and total PLFA in aggregates.
Values are means (n = 4) with standard error. Different letters denote significant differences between aggregates with the same treatment (a, b, c, d, e) and between treatments with the same aggregate (x, y, z) at P<0.05, respectively.
Figure 4.
Effect of long–term applications of fertilizer NPK and compost on concentrations (nmol g–1 aggregate) of monounsaturated and branched PLFA in aggregates.
Values are means (n = 4) with standard error. Different letters denote significant differences between aggregates with the same treatment (a, b, c, d, e) and between treatments with the same aggregate (x, y, z) at P<0.05, respectively.
Figure 5.
Relationship between increased organic C and the abundance of microbial PLFA (nmol g–1 aggregate) in soils.
Redundancy analysis (RDA) and regression analyses were used to test relationships between the increased organic C concentration in the CM and NPK treatments compared with the control and the abundance of microorganisms in aggregates in the CM and NPK treatments.