Abstract:The objective of this study was to investigate the effects of fire-derived black carbon on soil extractable nutrient elements in subtropical plantations. Three levels of black carbon input were applied to the experimental plots (10 m×10 m) by removing charred materials across the plots two weeks after slash burning in a Pinus massoniana Lamb. plantation. The three levels of black carbon were:B0, in which all visible charred materials were carefully removed from the plot; B1, in which all charred materials were left in place on the forest floor; and B2, in which all charred materials removed from the B0 plots and the double quantities of charcoal inputs were added. Soil samples were collected from 0-10 and 10-20 cm depth 1 year after charcoal application or removal. The results showed that:(1) The impact of black carbon input on soil major nutrients varied with sampling depth. At 0-10 cm depth, the contents of potassium(K), calcium (Ca) and magnesium (Mg) in B2 soils were significantly higher than those in B0 soils (P<0.05), which differences were not observed at the 10-20 cm depth. Available phosphorus (P) contents in B2 soils were significantly higher than those in UB soils at both 0-10 cm and 10-20 cm depth (P<0.05). (2) The amount of black carbon input had no effect on soil minor nutrients (P>0.05). Double the quantities of black carbon input significantly increased manganese (Mn) content compared with the UB soils (P<0.05). (3) There was no significant differences of soil SPAR, Ca/Al, and Ca/Mg except for Ca/Mg at the 10-20 cm depth, where Ca/Mg in B2 soil was significantly higher than those in B0 and B1 soil(P<0.05). In summary, our findings highlighted the importance of black carbon to improve soil fertility and structural stability in subtropical plantations subjected to slash burning in the short term. Future research should focus on the long-term impacts of black carbon on soil nutrient availability in subtropical plantations subjected to slash burning.