Estimation of Long-Term Above-Ground Biomass, Carbon Stocks and Carbon Dioxide Equivalent Lost Due to Deforestation in Mapfungautsi Forest, Zimbabwe

Abstract

Tropical forests play an important role of storing significant quantities of carbon, both, aboveground and belowground. However, deforestation activities for various purposes, among them, agriculture and settlement, have continued to remove unknown quantities of biomass and carbon stocks across tropical forests of Africa. This study was conducted to estimate aboveground tree biomass (AGB), carbon stocks (AGCS) and carbon dioxide equivalent (CO2 e) among three vegetation cover types (wooded land, bushland and grassland) found in Mapfungautsi forest and to quantify the long-term estimated total AGB, AGCS and CO2 e lost due to deforestation activities in the forest (between the year 2000 and 2020). Data collection was conducted using remote sensing imagery, field measurements and an allometric equation. A total of 22 plots, each measuring 50m x50m were established across the three vegetation cover types where tree height, diameter at breast height, number of stems/ha and regeneration were measured. The collected data was analysed using EViews Version 10 software. Wooded land generally had the highest values across all the four tree growth variables followed by bushland and grassland. The average estimated AGB stored were 50.78t/ha, 14.7t/ha and 8.2 t/ha for wooded land, bushland and grassland respectively. From the 10632ha cleared over 20 years, losses amounting to an estimated mean total AGB, AGCS and CO2 e of 387669.53t, 182205.09t and 668692.69t respectively were observed. We conclude that quantifying and raising awareness about the lost AGB, AGCS and CO2 e among stakeholders will lead to the implementation of remedial action to replenish the lost biomass and carbon stocks.