Biochar as Tool to Improve Physicochemical Properties of Chinese Albic Soils

摘要

The yield of crop is low in the Northeast China because of the albic horizon. The albic horizon is characterized by high compactness, low porosity, restricts soil aeration and water circulation. As a result, these soils are difficult for crops growing. The aim of this study is to research the effects of biochar on physicochemical properties of albic horizon of albic soil and the soybean yield. The experiment was carried out in the field with albic soils. The biochar was incorporated into albic horizon to load into the bottoms of the pipes with the following ratio (biochar: albic horizon = 0.0 g.Kg(-1) (B0), 66.7 g.Kg(-1) (B1), 200.0 g.Kg(-1) (B3) and 333.3 g.Kg(-1) (B5)). The soil of plough layer was fully mixed with fertilizers, and then the soil was loaded into the tops of the PVC pipes. The soil physicochemical properties, soybean growth parameters and yield were determined in soybean maturity period. The results showed the biochar significantly reduced the bulk density and specific gravity of albic horizon. In the other hand, it increased the total porosity, void ratio, aeration porosity, water content, total C, total N, total P, total S, total Ca, total K, C/N, available P, available K, pH(1:2.5) (H2O), pH(1:2.5) (CaCl2) and EC1:5 of albic horizon. The plenty of biochar application could reduce the specific surface area (SSA) of albic horizon. Compared to B0, B3 significantly increased the soybean yield in albic soil.