Topsoil and subsoil C and N turnover are affected by superficial lime and gypsum application in the short-term

Alleviation of subsoil acidity with lime or gypsum increases carbon (C) accumulation in deep layers by stimulating root growth and C nitrogen (N) inputs at depth. However, the effects these amendments combined N fertilization on soil CO2 emissions remain controversial. We evaluated superficial application N-fertilizer dynamics microbial use efficiency (MicCUE) samples taken from topsoil (0–10 cm) (40–60 a no-till field experiment carried out Brazil. performed short-term laboratory incubation 14C-glucose 14C-arginine to assess mineralization dynamics. Liming increased pH but had no effect acidity. A higher content organic C, total N, biomass were found topsoil. The addition corrective (lime gypsum) fertilizer MicCUE added 14C-glucose. was affected layer, subsoil. After arginine, net NH4+-N production highest control, while NO3−-N + plus residual same layer. conclude that ameliorate acidity, they have minimal cycling through biomass, particularly