Ecological Indicators (Feb 2023)
Large scale field-based evaluation of niche breadth, niche overlap and interspecific association of Western Himalayan temperate forest tree species
Abstract
Understanding niche and its parameters including niche breadth and niche overlap hold promise in discerning the needs, tolerances of organisms and also the extent of niche overlap among the sympatric species. Such information is critical to the conservation and management of important forest tree species. In view of the lack of any detailed previous study on this aspect in the Western Himalayan temperate forests of the Indian Himalayan Region, the present study was carried out to characterize niche in respect of their niche breadth, niche overlap and the interspecific association between various dominant species in 13 subtypes of Western Moist Temperate Forest and 4 subtypes of Western Dry Temperate Forest. Our study revealed that the niche breadth was high for Rhododendron arboreum and Cedrus deodara and low for Machilus odoratissima, Pinus wallichiana, Aesculus indica, Quercus lanuginosa and Cornus macrophylla. Niche overlap was high for the conifers (Abies pindrow and Cedrus deodara) followed by evergreen broad-leafed species (Quercus semecarpifolia and Rhododendron arboreum) and low for deciduous species (Aesculus indica). The variance ratio revealed that overall association between tree species of the Western Moist and Dry temperate forests were positive, i.e., tree species were associated with each other for their coexistence. However, the interspecific association between species yielded both positive and negative association between various pairs of dominant species of the forests. The present study provides empirical support and new insights into species cohabitation and adaptation to environmental change. The information is crucial for explaining species coexistence at regional and local scales for sustainable conservation and management of forests under global change.