Impact of Application of Biochar-Based Fertilizer on the Content of Phosphorus and Potassium in Soil

The application of chemical fertilizer can increase crop yield, but at the same time, it brings huge environmental pressure. Long-term application of chemical fertilizers resulted in deterioration of soil properties, excessive nitrate content in groundwater and increased emissions of greenhouse gases. The object of this study was to investigate application of biochar-based fertilizer (BBF) on the content of phosphorus and potassium in soil. An in-situ field experiment was conducted over 6 years in plain at Shenyang city in China. The experimental design involved five treatment, no fertilizer (CK), low levels of biochar (C15), high levels of biochar (C50), Chemical fertilization (NPK) and biochar-based fertilizer (BBF), with five three replicates of each treatment. Three (CK, NPK, BBF) was selected to research for the phosphorus and potassium in soil. After continuous application, the total phosphorus and potassium content was not affected by different additive. The content of available phosphorus in soil was increased by 1.19 and 1.42 times under chemical fertilizer and under BBF, respectively. The same phenomenon was also observed on available potassium. BBF can significantly improve the content of available phosphorus and potassium in soil, and the effect is better than applying chemical fertilizer. The peanut yield showed a significant increase under BBF than under others.