Land-use induced variability in soil profile carbon and carbon associated nutrient pools of Eastern Himalayan region

Context: Eastern Himalayan Region (EHR) exhibits strongly acid soils due to pedogenic and topographical matrix under sustained high precipitation regime. Prevalence of diverse and spatially varied land-use systems is the fundamental characteristics across these montane ecosystems and it plays a key role on its impact on different soil nutrient pools. Aim: The study was conducted to elucidate the impact of varied land use systems on nutrient mineralization dynamics, including carbon (C) and its associated pools. Methods: We selected fourteen ( 14) discrete land use systems and throughout all 14 land use systems, a random stratified sampling method was utilized in 56 quadrates that were exposed layer-wise up to a depth of 1.0 m. Result: The analytical results indicated that the land use systems had a significant impact on the pH of soil. Likewise, the total organic carbon (TOC) content indicated the significant variation (p 0.01) across land uses (0.40 to 4.61%) and along the soil depth. Irrespective of land use types, the soil profile up to a depth of 0.60m had high TOC concentration (2.35 to 6.01%) and carbon mediated microbial biomass nutrients (26.7 to 688.1 μg g -1 ). The bacterial and fungal populations were more concentrated at the top 0.6m depth, but they suddenly decreased beyond that depth. Conclusion: The association and clustering pattern of soil properties and different land use types identified through principal component analysis (PCA), suggest forest area, oak, alder, and apple plantations favoured the buildup of microbial biomass, enzyme activities, and bacterial viable populations.