Effect of different amounts of biochar on meadow soil characteristics and maize yields over three years

Abstract

To evaluate the effect of biochar on soil characteristics and maize yields in meadow soil, a three-year field experiment was performed using different amounts of biochar (0, 10, 20, 40, and 80 t/ha). The soil pH decreased over time when biochar was applied to weakly basic soil. Single biochar applications increased the organic carbon, total nitrogen, available K, and cation exchange capacity for three continuous years, in proportion to the amount of biochar applied. However, as time progressed, the soil organic carbon, total nitrogen, available K, and cation exchange capacity began to decrease. The biochar stimulated the availability of soil phosphorus in the meadow soil and stably increased the available P content in the soil for three years. For maize, the biochar application decreased the occurrence of barren ear tips and increased the ear length, grain number per row, 100-kernel weight, and yield. When the single applications of biochar were greater than 40 t/ha, the soil characteristics showed continuous improvements and the maize yields stably increased for three years.