Investigating the Effects of Biochar on Soil Properties and Alleviating Aluminum Toxicity for Improving Cabbage (Brassica oleracea var. Capitata) Productivity while Reducing Potash Fertilizer

The potassium (K) is an essential macronutrient and the availability of K in the soil is gradually decreasing which severely affecting crop productivity in the south of China The purpose of the present study was to investigate the effect of biochar on soil physicochemical properties and to explore the effect of biochar on substituting potash fertilizer in acid soil. Therefore, a pot experiment was conducted with two typical acidic soils (red and yellow-brown soil). The acid soil without biochar significantly inhibited plant growth and biomass accumulation in cabbage while biochar improved the growth parameters and nutrient contents in plant parts. Biochar completely replaced the potash fertilizer in red soil and up to 20% of potash fertilizer in yellow-brown soil. Biochar increased the pH by 1.3 units of acid soil and total soil Al and Al3+ in red soil and yellow-brown soils from 2694.71, 538.29 mg kg(-1) to 1170.58, 412.82 mg kg(-1) respectively. The leaf Al content was declined from 3879.6 to 614.65 mu g g(-1) in red soil. Taken together, it can be concluded that biochar-amended soil could increase the nutritional status and improve cabbage productivity by alleviating soil Al toxicity and replace potash fertilizer in a short period. (C) 2019 Friends Science Publishers