Abstract:

As important parameters of nutrient balance method, nutrient supplying capacity of typical black soil and fertilizer use efficiency of soybean can supervise fertilization and increase production of farms in Northeast China. An experimental area, Heshan Farm in Jiusan Agriculture Reclamation Substation of Heilongjiang Province, was chosen to determine these two parameters using pot experiment with local black soil (Isohumosols) and designing 8 fertilizer treatments (CK, N, P, K, NP, NK, PK, NPK) under current field fertilizer input levels. The results showed that, the supplying capacity of N, P2O5 and K2O for typical black soil (Isohumosols) were 63.28 kg/hm2, 50.15 kg/hm2 and 110.39 kg/hm2, respectively, and their use efficiencies were 15.99%, 5.12% and 78.79%. The estimated optimal fertilizer input amount should be 72.87 kg/hm2, and the ratio of N:P2O5:K2O should be 1:0.88:0.16, based on above parameters by using nutrient balance method. The current field fertilizer input amount was less by 39%, and with lower N level, higher P2O5 and K2O levels. Consequently, a changing of fertilizer amount and rate should be taken into account.