Aboveground Biomass Estimation of <i>Avicennia marina</i> (Forssk) Vierh. and <i>Rhizophora mucronata</i> Lam. in the Mangoky Delta, SW Madagascar

Abstract

Forty-three trees (23 Rhizophora mucronata and 20 Avicennia marina) were studied for the establishment of allometric relationships between the aboveground biomass "y" and the following dendrometric variables "x": diameter at breast height DBH, ( that is the best correlated for the estimation of less woody compartments (R 2 = 0.826 to 0.847). As for R. mucronata, these are much more related to DBH.For trees of 8 -10 m height, the aboveground biomass of the delta is higher (171 t·ha −1 for R. mucronata) than that of Puerto Rico, but quite comparable to that of Australia (110 t·ha −1 for A. marina). The first tools for estimating aboveground biomass are given for these two characteristic species of the Indo-Pacific Region and East Africa. Because of the low values of the regression coefficients for some allometric relationships obtained, precautions should be taken in case of extrapolation.