Interlinking community structure, regeneration, and species functional traits in the temperate forests of Tehri Garhwal, Western Himalaya

This study examined community structure, regeneration status, and trait-based successional patterns in the temperate forests of Tehri Garhwal, Western Himalaya, across an elevational gradient (1200–2000 m). Vegetation was sampled using nested quadrats to assess trees, saplings, and seedlings, and phytosociological attributes together with the Importance Value Index (IVI) were estimated. Regeneration was evaluated using size-class distribution (SCD) slopes, juvenile-to-adult ratios, and regeneration categories, while principal component analysis and multinomial logistic regression were used to examine relationships between functional traits and successional status. Quercus leucotrichophora and Rhododendron arboreum were the dominant canopy species and showed stable regeneration, whereas Pinus roxburghii and several mid-successional species exhibited poor seedling recruitment. Strongly negative SCD slopes indicated continuous recruitment in dominant species, while flatter slopes reflected regeneration constraints. Community composition varied along the elevational gradient, with distinct assemblages at lower elevations and gradual transitions towards higher elevations. Wood density, leaf dry matter content, SCD slope, and IVI were the principal predictors of successional status. The study highlights the combined influence of stand structure, functional traits, and environmental gradients on forest regeneration and community composition in the Western Himalaya.