Biodiversity, Carbon and Chocolate: Toward an Environmentally Friendly Cocoa Production System in Ghana

Thesis (Ph.D.)--University of Washington, 2019Global demand of cocoa for chocolate moved the native cocoa production frontier from ancient Maya and Aztec to other favorable tropical locations around the world. Cocoa growing arrived in West Africa sometime by the late 1800s and was an instant success story. A massive investment in the form of expansion of lands under cultivation, intensification driven by improved varieties/systems and a plethora of farming incentives have led West Africa to supply more than half of the world’s cocoa. Cocoa agroforestry provides a livelihood for many smallholder farmers and significant contribution to national economies; however, it also results in deforestation and land degradation. The traditional cocoa agroforestry system in highly forested tropical regions, utilized shade cocoa systems and require overhead canopy and favorable humidity to thrive. Thus, lands suitable for forest reserves or timber production, are also suitable for cocoa production. Land conversion of biodiverse High Forests in Ghana, part of the global biodiversity hotspot of the West African Guinean forest landscape, have allowed Ghana to become the second largest global cocoa producing nation. Cocoa led deforestation dominates the reported 2% rate of deforestation. In order to curb cocoa-led deforestation, it is essential to understand the crucial social, economic and environmental underpinnings of cocoa production. This study focuses on determining land use change and deforestation in the Krokosua Hills Forest Reserve, one of the most important cocoa producing areas of Ghana. Land use types are regulated within the reserve and timber production and protected area inside the reserve were compared with areas immediately outside the forest reserve over a 17-year period using multispectral satellite images acquired from Landsat and Sentinel earth observatory programs. A two-step land use pattern of change was observed, with closed forest land changing to open forest, and open forests were converted to croplands. These changes were mostly observed in areas of the forest reserve which have been technically designated as a production zone for wood/timber harvesting and admitted farming, in comparison to the areas specifically maintained for forest protection. Tree species composition varied significantly among the two broad management zones in comparison to uncultivated land within the forest reserve. Classifying tree species into ecological guilds depicts a natural reference condition of shade tolerant species, with non-pioneer light demanders among natural regeneration encountered in uncultivated areas. In contrast with other areas of the reserve where cocoa farming is interspersed with forests, regeneration of shade tolerant species is rare, with a greater amount of species as non-pioneer light demanders and pioneer species. Species composition of adult trees also showed a pattern of higher proportions of economically valuable species on cocoa farms compared with natural forest areas that are more diverse and have species represented in all the economic valuation classes of trees. In essence, cocoa farming promotes deforestation and species compositional changes that unequivocally present a challenge for forest management, particularly where objectives of cocoa farming and forestry are both emphasized within a broad land use category. This study suggests timber production and cocoa production, two vital industries in Ghana are connected with initial cutting leading conversion to cocoa. Cocoa production is susceptible to climatic variations which may be mitigated by environmentally friendly shaded cocoa production which effectively reduce associated deforestation. However, once cocoa farms are established, reduction of shade trees increases forest degradation, as farmers seek to increase cocoa yields. Therefore, land use change and the physical environment are interconnected. Since cocoa cultivation is essential to many livelihoods in Ghana, a changing global climate is of concern to smallholder cocoa farmers. Understanding cocoa farmers’ perceptions on topics of climate change and its impacts are thus necessary to assess the potential of recent economic incentives to enhance sustainable cocoa production. A social survey of farmers’ perception/knowledge of climate change and its potential effect on cocoa production was conducted to assess beliefs. I examined the potential of economic incentives of a REDD+ climate mitigation strategy as an alternative income generating avenue to maintain lower intensity, shaded cocoa production. Farmers’ perceptions of climate were not in agreement with empirical data. Although farmers recognize the need to protect trees to provide ecosystem benefits, the system of direct monetary benefits associated with tree protection/maintenance presents a challenge for the success of integrating climate change mitigation strategies (REDD+) into cocoa farming. Common farm/cultural practices of cocoa farmers (e.g. slash and burn) may also degrade land, reducing forest biodiversity and releasing carbon