Variation in carbon budget, diversity and demography trends of selected tree populations of Wari Maro Forest Reserve between 2009-2014

Abstract

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 three-dimensional methodology based on a diachronic analysis to establish half-decade 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 savanna-woodland vegetation. With these data, diversity index, crown cover of trees, biomass and carbon budget were estimated. Dynamics of these structural descriptors and demography of tree-populations 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 fire-resistant 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 savanna-woodlands.

Keywords: REDD+, greenhouse gases, biomass, tree mortality rate, timber logging rate