Abstract: The decomposition law of green manure and the nutrient release law of C, N, P and K in soil of Sophora alopecuroides during vegetative period and early flowering period were studied by nylon bag method. The results showed that after 118 days of decomposition, the mineralization rate of N and P in green manure increased gradually, and the mineralization rate of C in green manure was 66.59%. K mineralized rapidly from 0 to 7 days, with a mineralization rate of 55.46%, and mineralized 79.06% at 118 days. C/N showed a downward trend from 0 to 14 days, and became gradually stabilized from 14 to 118 days, and the nutrient mineralization rate was K>C>P>N. On 118 days, the dry matter（DM） decomposition of green manure reached 65.2%, and the mineralization rates of C, N, P and K reached 62.75%, 44.93%, 52.54% and 79.06%, respectively. Among them, 0~14 d was the rapid decomposition stage, 14~28 d was the slow decomposition stage, and 28~118 d was the slow decomposition stage. The dry matter degradation and nutrient release of Sophora alopecuroides green manure were basically synchronized and positively correlated.

Key words: Sophora alopecuroides, green manure, decomposing