Carbon dynamics with stand structure and species diversity in the Hindu Kush Himalaya ranges of Pakistan.

Information on forest carbon and diversity management and conservation is critical for achieving goals of climate action and life on land under UN SDGs. This study estimates carbon dynamics with stand structure, species composition, and diversity in the Hindu Kush Himalaya, ranges of Pakistan. A significantly higher carbon in mixed conifer broad-leaved forest (MCBL) followed by Cedrus deodara forest (CD) signifies the role of higher stand density and prevalence of larger trees in carbon regulation. The positive diversity carbon relation across the region and the occurrences of significantly higher carbon in diverse MCBL forest suggest that carbon-diversity conservation is synergistic. The results also revealed a positive effect of stand structure attributes and diversity on soil nutrients concentration, stock and stoichiometry as well on litter deadwood carbon. However, a negative effect of higher stand density and diversity was found on forest floor vegetation diversity and carbon. The higher carbon in poly-culture stands compared to most productive species provides useful insights on the conservation, restoration and raising of poly-culture stands as well species saturation of monoculture stands for sustainable carbon-diversity conservation. Poor regeneration status across the region with exclusion of management interventions is the insecurity to future carbon and diversity. Therefore, along with forest conservation and restoration programmes, the inclusion of selection and retention management system, conservation and community involvement are critical for sustainable carbon-diversity conservation and livelihoods.