Seasonal Variation in Carbon Mineralization Kinetics, Microbial Biomass Carbon and Enzyme Activities in the Soils of Three Natural Ecosystems of Kaziranga National Park, Assam, North East India

Soil acts as both source and sink of atmospheric carbon. The dynamic nature of forest soil makes them a critical component of the global carbon cycle. These necessitates the study of forest soil properties to predict their response on carbon storage. Seasonal dynamics of soil properties on soil carbon mineralization kinetics is helpful to understand the future environmental conditions on soil carbon storage. In this study, we have collected soils from three natural ecosystems (grassland, forestland and wetland) of the Kaziranga National Park of Northeast India. Soil samples were collected during pre-monsoon, monsoon and post-monsoon season for two consecutive years. In grassland and forestland ecosystem, soils were collected at two depths (0–15 cm) and (15–30 cm). The collected soils were analysed for soil microbial biomass carbon, extracellular enzyme activities and carbon mineralization kinetics. The studied soil parameters significantly varied with seasons and ecosystems. However, this variation decreased with the increasing soil depth. Conclusively, our findings documented that soil properties, microbial biomass carbon, extracellular enzyme activities, and carbon mineralization kinetics significantly differ across the seasons and ecosystems of Kaziranga National Park. The wetland ecosystem recorded the highest carbon mineralisation during the monsoon season. Further research is needed to explore the composition and function of soil microbial communities in different ecosystems throughout the seasons to accentuate our mechanistic comprehension of soil carbon dynamics of the studied ecosystems of Kaziranga National Park under changing climatic scenarios.