Abstract
Resin tapping of Pinus roxburghii (Chir pine) is a major livelihood source in mid-mountains of Nepal, yet its impact on tree growth under climate change remains poorly understood. We developed a 180-year tree-ring width chronology using tapped trees and a 216-year chronology using untapped trees from Jajarkot, western Nepal, to assess growth responses to resin tapping and climate variability. Both resin tapped and untapped trees followed similar growth patterns until the early 2000s, with sharp growth decline during severe droughts. After the onset of commercial tapping in 2014, growth trajectories diverged sharply tapped trees experienced an extreme growth decline exceeding −80% of mean annual growth change, whereas 89% of untapped trees entered a strong growth release phase, with amean of +30%. Growth-climate correlations indicated both tapped and untapped trees were positively associated with precipitation during September of the current and previous year (untapped: r = 0.24, tapped: r = 0.26–0.27, p < 0.05). However, tapped trees exhibited broader climatic sensitivity, including significant positive correlation with spring and early summer drought indices (SPEI: r = 0.24, p < 0.05). Summer warming negatively affected growth in both groups, although the response was stronger in tapped trees, particularly to June (r = −0.26, p < 0.05). These findings indicate that resin tapping substantially amplifies climate-induced growth sensitivity and intensifies growth decline. The combined impact of climate stress and resin tapping highlights the need for insight into sustainable resource harvesting and forest management under climate change.