Society Net Benefit from a Carbon-Based Agroforestry Project: Comparing Private Forest and Social Forestry in Garut Regency, Indonesia

Background: Carbon-based agroforestry projects are often assessed in terms of carbon sequestration and financial feasibility, with limited attention given to community net benefits after accounting for land opportunity costs. Objective: This study compares the modeled 21-year net benefits of agroforestry production at two adjacent sites comprising private forest and social forestry areas in Garut Regency, Indonesia. Methods: A bottom-up comparative case study estimates non-timber forest product income, deducting production costs, land opportunity costs, and farm tool expenditures, across 133.11 ha of private forest and 133.76 ha of social forestry. Net benefits are discounted at rates of 12% and 7%, with additional sensitivity and switching-value analyses and exploratory, expert-informed risk assessments. Project-related wages are excluded. Results: At a 12% discount rate, estimated net present benefits amount to IDR 43.77 billion (IDR 328.8 million/ha) for private forest and IDR 80.13 billion (IDR 599.1 million/ha) for social forestry. The per-hectare benefit ratio is 1.82, declining to 1.07 when avocado planting density is equalized in the model. The comparative ratio remains broadly stable under common changes in discount rates and yields. Conclusion: Avocado planting density accounts for much of the modeled benefit gap between the two sites. However, institutional explanations for this difference remain untested. The estimates represent partial site-level benefits rather than household welfare or benefit distribution and cannot be generalized without further evidence.