Changes in Soil Organic Carbon and Its Labile Fractions after Land Conversion from Paddy Fields to Woodlands or Corn Fields

Land use change could significantly affect soil organic carbon (SOC) and other chemical properties. However, the responses of labile C fractions at different depths to land-use are not still clear. The aim this study was investigate effect paddy field conversion on woodlands or corn fields total (TOC) its including particulate (POC), microbial biomass (MBC), potassium permanganate-oxidizable (KMnO4–C) along a 0–100 cm profile. Our results indicate that TOC concentrations increased by 3.88 g kg−1 3.47 in 0–5 layer 5.33 4.68 5–20 during 13 years after from fields, respectively. In 20–40 layer, had highest concentration (12.3 kg−1), which 5.13 3.5 higher than increase probably due absence disturbance greater root residue input into woodland soil. pig manure addition contributed concentrations. addition, proportion KMnO4–C 0–40 ranging 39.9–56.6% for 24.6–32.9% fields. POC content soils lower (5–40 cm). there were no differences MBC contents whole profile between most important factor affecting CMI values through Overall, converting layer. Future studies should focus response deeper pool change.