Abiotic stress affects resistance and resilience capacity of soil respiration under long-term manuring and fertilization in an Alfisol

Abstract

Present study was undertaken to evaluate the impact of long-term fertilizers application on substrate induced soil respiration (SIR), their resistance and resilience against heat stress (48°C for 24 h) of an acidic soil under sub-humid climate. To achieve this, soil samples (0-15 cm depth) were collected from five treatments viz. control, 100% NP (NP), 100%NPK (NPK), 100% NPK+FYM (NPKF) and 100% NPK + lime (NPKL) from long-term fertilizer experiment (LTFE), Birsa Agricultural University, Ranchi (since 1971) at pod formation stage of soybean crop (2018).Resistance and resilience capacity of soil SIR being analyzed at 1 and 30 days after heat stress (DAS). Results revealed that, SIR was significantly affected by long-term fertilization and heat stress. Balanced fertilization along with lime application (NPKL) had significantly higher SIR rate (10.78 mg CO2 g/soil/ h) followed NPKF, NPK, control and NP treatments. After 1 DAS, the SIR increased at 24 hour of substrate addition. However, during the 24-48 hours, the SIR value decreased significantly and maximum reduction was noticed under control treatments (47%). Cumulative SIR decreased significantly after heat stress, maximum reduction being in NPKL and NPKF treatments, whereas minimum under control. NPKF = NPKL treatments recorded highest resistance (0.86) followed by NP (0.82) > NPK (0.79) > control (0.61).Resilience index of NPKL (0.52) and NPKF (0.50) were highest and superior over other treatments. In nutshell, SIR emerged as a good indicator to asses’resistance, resilience capacity of soil against heat stress.