Effects of Combined Application of Chemical Fertilizer and Biochar on Soil Physio-Biochemical Properties and Maize Yield

Excessive, long-term chemical fertilizer application adversely affects soil quality and maize yield. The combined of biochar with can increase yield improve fertility. A four-year field experiment was conducted to determine physio-biochemical properties under a soybean–maize rotation in the black soils Northeast China. There were five treatments, including no fertilization (CK), (NPK), + (15.75 t·hm−2, BC1), (31.50 BC2), (47.25 BC3). Compared CK, number macroaggregates average weight diameter aggregates BC2 treatment increased significantly by 10.3% 24.5%, respectively. pH study area 7.03, it all treatments except for BC1. highest 7.17 recorded NPK which around optimal pH. In contrast CK organic carbon (SOC) total nitrogen (TN) content. improved C/N copy bacteria 25.6% compared CK. better than alone, mechanical composition fine particle contents (powder clay). Mixed also 100 grains from 9.5% 10.9% three higher applied order > BC3 BC1 (BC2 34.8%). Additionally, positively correlated aggregates, (p < 0.05) as well 100-grain 0.01). 31.50 t·hm−2 treatment) enhance physicochemical