Wood specific gravity of trees in hot semi-arid zone of India: diversity among species and relationship between stem and branches.

Abstract

Wood specific gravity (WSG) is an important parameter in allometric equations for accurate estimation of C-sequestration and other functional properties of a tree. However, WSG of many tree species especially of arid and semi-arid regions is poorly reported. Further, identifying indirect methods for determination of stem WSG from branches may be rapid and relatively easy. The present study determined WSG of stem and branches of 21 tree species in the hot semi-arid region of Western India. Three individual trees from each species were randomly selected and sampled for determination of WSG of stem, primary and secondary branch. WSG varied significantly among the species (F = 42.83, P < 0.001) and sampling locations (stem and branches) (F = 29.43, P < 0.001). In stem (at DBH), it ranged from 0.42  0.04 to 0.74  0.03 among the species while within an individual tree it varied in order of stem > primary branch > secondary branch in most species. WSG of stem and branches showed linear relationship and branches were found a good predictor of stem WSG (R 2 > 0.83).