Changes in Soil Carbon Storage Potential Following Conversion from Afromontane Forest to Plantations and Cultivated Land in Komto Watershed, Western Ethiopia

Abstract

Forest ecosystem takes the lion share of soil C store compared to other land use systems. The study was aimed to examine the influence of land use change on soil C sequestration potential under varying soil layers. Heterogeneity in soil C storage was observed across land use types and along soil layers due to disparity in spatial distribution of soil C densities arising from the influences of variations in land cover types and management practices. The average soil C stock varied from 14.16 Mg ha^-1 for the cultivated land to 35.24 Mg ha^-1 for the natural forest, and 21.48 Mg ha^-1 for of plantation forest to a depth of 60 cm. The average soil C loss rate after 25 years period of conversion from Afromontane forest to plantations and cultivated land were estimated to be 0.55 and 0.84 Mg ha^-1 yr^-1, respectively. Encroachment of native forests coupled with unwise agricultural management practices contributed to SOC depletion and subsequent CO₂ emission. Integrated land use systems that combine trees and agricultural crops can increase C sequestration potential while giving multiple products for the land users.

Keywords: Land use change, Afromontane forest, soil carbon storage, soil carbon loss, climate change