The Himalayan Treeline and the Associated Dynamics: Understanding the Ecological Challenges and Livelihood Threat to the Dependent Population

This study is a review article which examines the dynamics of the treeline shifts in the Himalayan region of India. It further looks at its impact on ecology, resources and the local communities. The previous studies have found that the Himalayan region is warming at rates faster than the surrounding lowlands. In Himalayas, changes in temperature and precipitation patterns over recent decades have led to significant alterations in treeline ecology, affecting both the landscape and the livelihoods of the communities. As per the previous studies, the Indian Himalayan treeline has shifted significantly upward from 1972-2014. Arunachal Pradesh now has the highest treeline at 4136m (shifted up 452m), followed by Jammu and Kashmir at 4121m (shifted up 441m). Uttarakhand's treeline moved up 411m to 3615m, while Himachal Pradesh and Sikkim both rose about 301m to reach 3520m and 3542m respectively. This study documents temporal changes in altitudinal treeline positions based on available literatures, its associated vegetation dynamics, and their socioeconomic implications for local and transhumant communities. The investigation of several literatures reveals that there has been an upward shift of the treeline in most of the Himalayan region. These shift varies from 300-600m spatially. This threatens alpine meadows, which are critical for local biodiversity and traditional pastoral practices. Grazing areas and other forest resources are becoming less productive and cannot meet the growing demands of both human and livestock populations. The research documents a decline in the availability of essential resources, including medicinal plants, timber, firewood, and grazing grounds, forcing collectors to venture into more remote areas. Additionally, based on number of studies, the article shows how climate-induced changes coupled with increased developmental activities such as road construction impact the treeline ecotone and associated livelihood patterns. The fragile mountain ecosystem, experiencing increased frequency of climatic anomalies has led to devastating effects on local communities. By integrating ecological and social dimensions, this study contributes to a holistic understanding of treeline dynamics and their implications for community well-being.