Carbon mineralization characteristics of compost made from pruning material

Abstract

To investigate carbon (C) mineralization characteristics of compost made from pruning material (PM), C mineralization parameters were evaluated, including mineralizable C (C0), apparent activation energy (Ea), and the rate constant of mineralization (k). These properties were also examined in conventional composts made from dung (D), fallen leaves (L), and bark (B). No significant differences among the plant composts (L, B and PM) were observed for Ea. Notably, the values of the respective indicators were significantly greater in PM, L and B than in D. The C0 of PM was significantly greater than that of the other composts. Conversely, the k-value for PM was significantly smaller than that for the other composts. These results indicate that PM supplies a substantial amount of mineralizable C that persists for a long time after the PM has been mixed with soil.