Criteria and indicator for assessing threat on Himalayan birch (B. utilis) at timberline ecotone of Nanda Devi Biosphere Reserve: A world heritage site, Western Himalaya, India

Himalayan birch (Betula utilis), a keystone species at the timberline ecotone of Nanda Devi Biosphere Reserve, is critically threatened due to unsustainable exploitation. The study found that while seedlings and saplings show growth potential, adult populations are declining rapidly, with B. utilis ranked as the most vulnerable species (threat score: 29). Annual extraction for fuelwood (927.10 kg capita⁻¹ yr⁻¹) and bark (551.15 g capita⁻¹ yr⁻¹), driven by demand for Ophiocordyceps sinensis, exacerbates this decline. The research employed rapid threat assessment and phytosociological studies to evaluate species diversity, density, and regeneration potential across 13 timberline ecotones. Findings highlight the urgent need for conservation policies balancing ecological protection with local socio-economic development.

Maletha, A., Maikhuri, R. K., & Bargali, S. S. (2020). Criteria and indicator for assessing threat on Himalayan birch (B. utilis) at timberline ecotone of Nanda Devi Biosphere Reserve: A world heritage site, Western Himalaya, India. Environmental and Sustainability Indicators, 8, 100086. https://doi.org/10.1016/j.indic.2020.100086