Assessment of Soil Quality, Carbon Stock and Sequestration Potential Across Diverse Land Cover and Land Use Types in the Himalayan Region

In this study, samples of soil, litter, sediment, and deadwood were systematically collected from different sites. The collected soil samples were analysed to assess a range of physical (Moisture content, bulk density, Soil aggregates), chemical (pH, EC, organic carbon, organic matter, nutrients, heavy metals), and biological (microbial biomass) parameters using standard analytical methods. Above-ground and below-ground biomass carbon were estimated using standard allometric equations, while carbon content was measured across five key pools—vegetation, litter, deadwood, soil, and sediment. Soil quality was statistically evaluated through Principal Component Analysis (PCA), Correlation Matrix, and Cluster Analysis to derive the Minimum Data Set (MDS) and calculate SQI to evaluate variations across different sites. The results found marked differences in biomass and carbon accumulation across forest types, with Cedrus deodara forests in Mussoorie and the Selaqui region of Dehradun exhibiting the highest total biomass, indicating their strong potential for carbon retention. Conversely, sites such as Premnagar, Asan Wetland, and pine forests in Mussoorie showed lower biomass values. Selaqui recorded elevated microbial biomass and soil organic carbon, while Panditwari exhibited higher levels of available nutrients. Mussoorie’s forest soils, particularly under deodar cover, showed greater organic matter and moisture content, signifying enhanced carbon storage. In terms of soil properties, soil pH ranged widely, with significant relationships observed between pH, electrical conductivity, and microbial indicators. Principal Component Analysis (PCA) revealed that 75% to 100% of the total variance in soil properties could be explained through three to five components, depending on site complexity. Premnagar had the highest SQI value (1.03), indicating excellent soil functionality, whereas Shishambara scored the lowest (0.54), reflecting poor organic content and compaction issues. The study concludes that carbon sequestration potential and soil quality vary greatly across landscapes and are closely tied to vegetation type, land use, and ecological conditions.