Effect of Different Fertilizer Treatments on Nutrient and Enzymatic Activity of Soil in River Ancient Channel

A field fertilizer experiment was made to explore the effect of different fertilizer treatments on soil nutrients and enzyme activity in different layers of river ancient channel.The results indicated that fertilizer combination of urea(512.22 kg/hm2),P2O5(191.11 kg/hm2) and K2SO4(791.53 kg/hm2) was the best treatment for improving nutrients availability in soil.The available phosphorus and available potassium contents of the soil in 0~20 cm depth were increased by 107% and 84.6%,respectively.There was no significant difference in full amount of soil nutrients.The activities of alkaline phosphatase and catalase in fertilizer combination of urea(512.22 kg/hm2),P2O5(191.11 kg/hm2) and K2SO4(263.84 kg/hm2) were the highest;the activities of urease and alkaline phosphatase were significantly higher in upper soil layer than in lower soil layer,but the soil catalase activity was not significantly different in different soil layers.