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

Background 

Global climate change and biodiversity loss underscore the importance of forests in climate change mitigation and ecosystem stability, as highlighted by UN Sustainable Development Goals 13 and 15. The Hindu Kush Himalaya region in Pakistan is a critical biodiversity hotspot and a significant carbon reservoir. However, the relationships among forest structure, species diversity, and carbon storage in this region remain poorly understood, particularly under current management exclusions and anthropogenic pressures.

Goals and Methods

This study aims to quantify carbon dynamics in relation to stand structure, species composition, and diversity across five forest types in the Kumrat Valley. Using a randomized plot design, researchers measured tree dendrometric variables, forest floor vegetation, litter, deadwood, and soil nutrients across 100 sample plots. They calculated biomass carbon stocks, soil nutrient concentrations, and diversity indices (Simpson, Shannon, dominance) to analyze associations between forest attributes and carbon storage.

Conclusions and Takeaways 

Mixed conifer-broadleaf forests (MCBL) exhibited the highest carbon stocks, driven by greater stand density, large trees, and species diversity. A positive correlation between diversity and carbon storage supports synergistic carbon-diversity conservation. However, poor regeneration due to management exclusion and anthropogenic disturbances threatens long-term carbon and biodiversity. The study recommends promoting mixed-species stands, integrating selective management and gap disturbances to enhance regeneration, and involving communities in conservation efforts. These strategies are essential for achieving sustainable carbon storage, biodiversity conservation, and local livelihood security in the region.