The role of forests in the mitigation of global climate change: Emprical evidence from Tanzania

The contribution of forests in regulating climate relies on the extent of forests. Therefore, mapping and monitoring changes of forests are fundamental and should be accurate. This study therefore assessed the potential role of forests in Tanzania in mitigation of climate change by (1) assessing extent of forests, deforestation, and accounted for their mapping errors, (2) estimating quantities of CO2 stored and sequestered by forests, (3) estimating quantities of CO2 emitted due to loss of forests. The study also hypothesized that, forests in Tanzania are net sink of CO2. Findings revealed that, the extent of forests for Mainland Tanzania in 2013 was 46,239,549 ± 1,400,514 ha while deforestation (2002–2013) was 469,016 ± 57,272 ha year−1. It was further observed that, the use of unbiased estimator to account for errors in classification of forests and deforestation improved the forest extent and deforestation estimates significantly. Total carbon stored by forests was estimated at 5.8 Gigatons CO2e while the total quantities of carbon sequestered by forest remaining forests for the period 2002–2013 was about -0.4 Gigatons CO2e year−1. Besides, carbon emissions due to deforestation (2002–2013) was estimated at 0.04 Gigatons CO2e year−1. The current level of emissions from deforestation is high and needs to be addressed urgently. Despite that emissions from deforestation are high, the study demonstrates in quantitative terms that forests in Tanzania were net sink of CO2 (-0.3 Gigatons CO2e year−1) hence regulate and stabilise global climate system by reducing the concentration of atmospheric CO2 through carbon sequestration. Improved land use planning, enhanced inter-sectoral coordination, upscaling of participatory forest management particularly in village forests, enhanced performance of institutions mandated to manage forest resources and taking advantages of climate finance opportunities are recommended as means of achieving emission reduction and sustaining the role of forests as carbon sinks.