Response of Soil Phosphorus to P Balance Under Long-Term Fertilization in Fluvo-Aquic Soil
[Objective]Soil phosphorus is essential indexes for assessing soil fertility, so the responses of Olsen phosphorus (Olsen-P) and total phosphorus (TP) to P balance under various long-term fertilization were studied, which can provide a scientific basis for improving fertilization management and soil fertility in fluvo-aquic soil.[Method]The relationships between Olsen-P, total P change, and the budget of soil P balance in the treatments of CK, N, NP, NK, PK, NPK, NM, and NS were studied by the method of linear regression based on a 34-year field experiment in Tianjin, China.[Result]The results showed that under long-term application of N, NK, NS, and without fertilizer (CK), the P balance of the plough layer (0-20 cm) always remained a wane status, with a surplus of P balance in the PK, NP, NPK, and NM treatments, and the most P accumulation in the PK treatment. But the P balance showed a decreasing trend with cultivate time in the P fertilize and manure treatments, especially 20 years later. Applications of PK, NP, NPK, and NM increased the amount of Olsen-P significantly. The Olsen-P was significantlycorrelated with the P balance (P<0.05). For every 100 kg P·hm-2 surplus, there would be 3.59, 1.19, 1.75, and 2.40 mg·kg-1 increase in Olsen-P in the PK, NP, NPK, and NM treatments, respectively. There were positive relationships between total P and P balance under long-term different fertilization, and different treatments had significantly different effects on the relationship between total P and P balance. We can assume that P balance had no effects on total P in N and NS treatments. With an average surplus of 100 kg P·hm-2, the total P increased by 0.06, 0.07, 0.07, and 0.10 mg·kg-1, in the PK, NP, NPK, and NM treatments, respectively.[Conclusion] The status of soil P balance was closely related to the type of fertilizer application. The increment of Olsen-P and total P caused by application of chemical P fertilizer or manure were significantly and positively linearly correlated with soil P balance. The increase of TP under long-term application of manure with chemical N is higher than that under chemical P in fluvo-aquic soil.
国家科技期刊平台
NSTL
万方数据
维普
