Papers by Mohamed Mahmoudi
Monitoring forests in order to understand the impact of global climate changes on terrestrial eco... more Monitoring forests in order to understand the impact of global climate changes on terrestrial ecosystems has become of great importance. In fact, to characterize forest changes, it is useful to parameterize a forest by using several parameters such as biomass, basal area, tree density, tree height, and trunk diameter at breast height. Ten trees of natural Mirbeck's oak (Quercus canariensis Willd. = Quercus Mirbecki Dur.), representative of the main diameter classes, were harvested from four sites in Kroumirie. Allometric equations were established for estimating tree above-ground dry-weight. Diameters at breast height (DBH) of felled trees ranged from 4.8 to 48.4 cm, total heights from 4.49 to 18.33 m and dry-weights from 5934 to 1989.069 kg. From these parameters, a number of biomass equations including trunk wood mass, trunk bark mass, branches wood mass, branches bark mass, twigs and buds mass, foliage mass and total branches mass were developed and tested statistically. Non-linear models based on trunk diameter at breast height (DBH) alone explained more than 98% of the biomass variation. Within all these parameters, strong site independent correlations were observed. Coefficients of determination (R 2 ) for the selected total biomass models ranged from 0.8996 to 0.9822. Equations for wood trunk biomass and foliage biomass have showed higher coefficients of determination than did equations for either bark trunk biomass, branches biomass, twigs and buds biomass or total branches biomass of these deciduous tree species
Materials Chemistry and Physics, 1992
On the basis of the gaussian non local pseudopotential method and the virtual crystal approximati... more On the basis of the gaussian non local pseudopotential method and the virtual crystal approximation which lead to the determination of the pseudocharge densities for the alloy ZnXHgCl_,,Te. The comparison between contributions of each valence band to the total valence band charge densities at different high symmetry points and for different stoichiometric coefficients x are discussed.
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Papers by Mohamed Mahmoudi