Abstract:In order to explore the effects of organic mulching on soil organic carbon (SOC) mineralization and oxidation stability in urban forest, soil samples were collected from Jiufeng National Forest Park for incubation experiment. Four treatments were applied: 1) no organic mulch (CK); 2) wood chips alone (Mw); 3) wood composts alone (Mc) ; 4) the upper layer wood chips + the lower layer wood composts (Mw+c).The results showed that organic mulching significantly affected SOC mineralization in the soil (P<0.05), and the cumulative mineralization of SOC under Mc, Mw+c and Mw treatments was 1.77, 2.93 and 3.98 times that of CK. Ratios of cumulative mineralization amount to SOC contents and Cp/SOC under Mw treatment was significantly higher than those of Mc and Mw+ctreatments (P<0.05), which showed that Mc and Mw+ctreatments had higher carbon sequestration capacity than Mw treatment. Organic mulching significantly increased SOC contents and oxidation stability fractions (P<0.05). Compared with CK, SOC content of Mw+c was increased by 29.14%, and the contents of very active organic carbon (VAC) and partially organic carbon (PAC) were increased by 20% and 37.14%, respectively. Organic mulching increased SOC stability index and decreased activity index, indicating that organic mulching enhanced SOC stability. The cumulative mineralization of organic carbon was very significantly positively correlated with VAC (P<0.01), and significantly positively correlated with SOC and PAC (P<0.05). As a whole, Mw+c treatment is beneficial for soil organic carbon sequestration, and it also can balance the organic carbon mineralization and sequestration.