Abstract
This study investigates the carbon (C) sequestration of traditional cocoa agroforestry systems in the Eastern Region of Ghana and the theoretical impact of CO 2 emission rights trading on their profitability. The study was conducted in four villages of Suhum Municipality, two each with either conventional or organic cocoa cultivation systems. Profitability was calculated using net present value of net cashflow (NPV), benefit cost ratio (BCR), and modified internal rate of return (MIRR). Carbon revenues were calculated using CO 2 emission trading rights prices ranging from 7.5 € t CO2eq. −1 (average EU trading price) to 42 € t CO2eq. −1 (estimated social cost of CO 2 release). We tested the sensitivity of profitability indicators with three scenarios: 300% increase in interest rates, 20% yield reduction, and 10% increase in cost. NPV without CO 2 payment for conventional agroforest was 20% higher than that of organic agroforest. Contrarily, BCR for the organic system was 30% larger than for the conventional counterpart. Profitability indicators for both systems were most sensitive to the 300% interest rate. The average C sequestered was 153 ± 13 t ha −1 whereby soil contributed the largest fraction with an average of 88 ± 11 t ha−1. Total C sequestered in the organic system was 30% higher than in the conventional system. In conclusion, CO 2 payments can improve the attractiveness of organic cocoa cultivation for farmers, although the paid price must be oriented to the estimated social costs caused by CO 2 release rather than the currently used trading price in the EU.