Examining the impacts of socio-ecological factors on woody carbon stocks under different agroforestry practices in Northwestern Ethiopia

Woody species under agroforestry practices offer a range of ecosystem services to smallholder farmers in agricultural landscapes across different tropical regions. Nevertheless, empirical evidence is scarce regarding the regulatory services, such as carbon stocks, provided by woody species and the factors that affect them. To fill this gap, we assessed the woody carbon stocks under different agroforestry practices and the socio-ecological determinants in the northwestern Ethiopia. For this, a multistage stratified random sampling technique was employed to identify 90 household heads and assess the woody carbon stock by using 175 sample plots. The data were analyzed using one-way analysis of variance, simple linear regression, and a linear mixed effects model and by using R software version 4.3.2. The results showed that the woody carbon was significantly higher in woodlot (10.4 ± 4.66 Mg C ha-1) when compared with homegardens (4.37 ± 2.35 Mg C ha-1) and parkland (4.28 ± 2.17 Mg C ha-1) agroforestry practices (p < 0.001). Moreover, the woody carbon was significantly higher in midland (8.22 ± 4.04 Mg C ha-1) when compared with highland (3.20 ± 1.68 Mg C ha-1) altitudinal gradients (p < 0.001). The woody carbon stock was positively associated with basal area, diameter at breast height, height, species richness, and species diversity (p < 0.001). The results also showed that the woody carbon stock was significantly higher in rich household (7.89 ± 4.12 Mg C ha-1) when compared with medium (3.82 ± 1.46 Mg C ha-1) and poor (2.35 ± 0.928 Mg C ha-1) households (p < 0.001). Overall, the results highlighted that socio-ecological factors such as altitudinal gradients and wealth status affect woody carbon stocks under agroforestry practices. Thus, the policymakers need to take into account such holistic inputs when implementing carbon-focused policies are imperative for achieving sustainable land management (SLM) and hence climate change mitigation (CCM) efforts in agricultural landscapes.