Carbon–economy trade-offs in agroforestry: an integrated multi-criteria assessment from Nepal’s Churiya Hills

Abstract Agroforestry is widely promoted as a climate-smart land use system, yet most studies evaluate its carbon, economic, or opportunity-cost dimensions in isolation, leaving the integrated trade-offs faced by smallholders unclear. In this study, we compared the integrated performance of three agroforestry systems: agri-silviculture, silvopasture, and homegarden in Nepal’s Churiya region. Carbon stocks across five pools (above and below-ground biomass, saplings, litter, and soil organic carbon) were measured. Also, household economic data collected yielded net present value (NPV), benefit–cost ratio (BCR), and opportunity cost per tCO 2 e. The three normalized indicators (total carbon stock density, BCR & cost-efficiency) were combined into a weighted Ratio-Based Performance Index (RBPI), with a sensitivity analysis under four different weighting scenarios. Total carbon stocks did not differ significantly across all three systems however agri-silviculture accumulated total carbon faster annually than silvopasture and homegarden. All three systems were financially viable, with cumulative three-year NPVs ranging from USD 939 to 4097 ha −1 . The benefit–cost ratio identified silvopasture as the most financially attractive agroforestry system, while homegardens delivered the lowest opportunity cost of carbon. The RBPI ranked silvopasture as the highest, homegarden as the intermediate, and agri-silviculture as the lowest, and this ranking held across all four weighting scenarios. Hence, silvopasture emerged as the most balanced multifunctional system in the Churiya context, with homegardens occupied a complementary low-income, carbon-priority niche. Realizing these gains, however, will require institutional support, durable tenure, and farmer-led extension embedded within Nepal’s existing community-forestry architecture.