Abstract: 【Objective】 Purposes of this study are to determine if biochar has effects on red soil under precipitation conditions, and the difference between no-fertilization soil and fertilization soil.【Method】A rainfall simulation experiment was carried out with different biochar levels (biochar/soil: 0%, 1%, 2% and 3%) on red soil, and some characters such as soil available phosphorus (SAP), available potassium (SAK), nitrate nitrogen (SNN), ammonium nitrogen (SAN), organic carbon (SOC) and active aluminum (SAA) were determined.【Result】Under precipitation conditions, the variation of SAN, SOC, SAA and pH in red soil was observably. When 3% biochar was added, the change of soil characters was most significantly. Compared with the no-fertilization control (CK), soil pH raised by 0.60, SAA decreased by 91.1%, the descent range of SAK decreased by 9.5%, the descent ranges of SAP and SNN, respectively, increased by 33.2%, 40.5% in no-fertilization soil with 3% biochar application. Compared with the fertilization control (F), soil pH raised by 1.09, SAA decreased by 94.8%, the descent range of SAK decreased by10.3%, the descent ranges of SAP and SNN, respectively, increased by 23.4% and 21.9%, SOC and SAN, respectively, increased by 23.6% and 5.4% in fertilization soil with 3% biochar application rate.【Conclusion】Under precipitation conditions, biochar was propitious to maintain SAP, improved soil pH and SOC, and decreased SAA, especially in red soil with fertilizer application.

Key words: biochar, simulating rainfall, red soil, soil characters, fertilization