Using agricultural originated biochars to improve chemical properties of an acid soil and wheat yield

Biochar is the carbon-rich product obtained when organic material pyrolyzed in a limited supply of oxygen. Using of biochar as soil amendment has been reported with positive effects on soil quality and crop productivity. The objective of this study was to evaluate the effect of biochars generated from various agricultural wastes on soil chemical properties of moderate acidic clayey loam soil and wheat yield. 5 months greenhouse pot experiment was conducted to gain insight on effect of biochars originated from various agricultural biomasses on soil chemical quality and wheat yield. The four types of biochars used were rice husk biochar (RHB), hazelnut waste biochar (HWB), wheat straw biochar (WSB), and tea waste biochar (TWB). The design of experiment was completely randomized with three replicates. The biochar application rate was 2%. At the end of experiment, soil chemical properties and wheat yield components were analysed. All the applied biochars altered soil pH signifying liming potential of biochars and their effectiveness on improving the quality of acid soils. HWB, TWB, WSB, and RHB improved soil pH by 0.52, 0.22, 0.21, 0.13 unit respectively, compared to control. TWB increased EC by 22% while RHB decreased EC by 26%. HWB, TWB, and WSB increased SOC by 21%, 18%, and 7%, respectively, compared to control. HWB and WSB increased exchangeable Ca by 50% and 11% respectively, RHB and TWB reduced exchangeable Ca by 31% and 13%, respectively, compared to control. Only RHB significantly improved exchangeable Mg by 39% compared to control. All the applied biochars significantly increased exchangeable K; HWB (782%), TWB (630%), WSB (365%) and RHB (139%). Biochar applications showed insignificant effect for exchangeable Na. TWB, HWB and WSB significantly increased CEC by 13%, 7%, and 7%, respectively. HWB and TWB increased available P by 72% and 33% respectively, compared to control. HWB increased biomass yield and grain yield by 102% and 510%, RHWB by 57% and 466%, WSWB by 57% and 459%, respectively. Biochar applications showed varied effects on soil properties and wheat yield components. Hazelnut waste biochar demonstrated higher capacity on improving both soil chemical parameters and wheat yield components. Tea waste biochar improved most of soil chemical parameters but not wheat yield. Observed variation on soil chemical properties and wheat yields suggesting that type of feedstock and biochar composition have primary effect on influencing the quality of soil and yield.