Wood specific gravity in Indian forests: A review.

Abstract

Wood specific gravity (WSG) is an important attribute for biomass estimation of forest trees. It is an important factor in converting forest volume into biomass. However, a number of factors like climatic condition, geographic location, management practice, age of tree, location of sample collection etc. may affect WSG. In India, forests have been classified into 6 major groups, 16 groups and other sub groups on the basis of climatic, edaphic and successional variations. A number of studies conducted on above ground biomass and carbon stock using non-destructive method used global, regional or reported WSG leading to inaccuracies in biomass estimation. The present paper is a comprehensive review on methodology of wood specific gravity estimation, wood specific gravity values of a number of species reported from different forest groups of India. A total of 88 critical research papers and reports for last 20 years were found meeting the aims, were collected from relevant sources. Methodology for determining WSG is discussed for accurate estimation. Comparative analysis of common species distributed in different forest groups does not show a generalized trend for WSG, as the same forest group does not exhibit similar WSG in tree species. However, it is evident that juvenility effect has greater bearing on wood specific gravity variation than climate. Analysis of data shows a greater bearing of edaphic factor on WSG, than the climatic factor. It is suggested that for estimation of biomass, habitat specific WSG is ideal to attain accuracy.