VARIATION IN CARBON BUDGET, DIVERSITY AN BUDGET, DIVERSITY AND DEMOGRAPHY TRENDS OF SELECTED TREE POPULATIONS OF WARI MARO FOREST RESERVE BETWEEN 2009-2014
F. SINSIN*, R. GLÈLÈ KAKAÏ**, S. GUENDÉHOU*** & B. SINSIN *
DOI :
https://doi.org/10.2023/mvvcqd06Mots-clés :
REDD+, greenhouse gases, biomass, tree mortality rate, timber logging rate.Résumé
Illegal timber logging and bush fire in tropical savanna woodlands create an uncontestable mortgage for
climate change mitigation. To investigate this hypothesis, we proposed a threedimensional methodology
based on a diachronic analysis to establish halfdecade changes in floristic diversity and carbon budget.
Data on trees and stump density, diameter at breast height, tree heights and crown diameter were
collected from all trees whose diameters equal or exceed 10 cm at the breast height. And these were
investigated from a permanent plot of 1 ha set up in savannawoodland vegetation. With these data,
diversity index, crown cover of trees, biomass and carbon budget were estimated. Dynamics of these
structural descriptors and demography of treepopulations with a special focus on tree logging, mortality
and recruitment rates were considered with the aim of appraising how deforestation contributes to
emission of greenhouse gases. Key outcomes of this research revealed that from 2009 to 2014, the woody
average species’ richness of the Wari Maro Forest Reserve dropped from 15 to 14 species per hectare. The
Shannon & Wiener diversity index and the equitability index of Pielou were almost invariable. Conversely,
considerable changes were observed as regard to tree density, basal area, crown cover and carbon pool.
Occurred modifications were negative for species coveted for their timbers, and positive for species less
desired for timbers as well as for fireresistant species. A huge loss in both trees density and carbon budget
was observed with Daniellia oliveri timber which is not even yet subjected to logging. As compared to
natural tree mortality and recruitment rate, the timber logging rate makes the fight against illegal timber
logging as the sine qua non condition for expecting reduction of emission from deforestation and forest
degradation in tropical savannawoodlands.
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