Characterization of cocoa production, income diversification and shade tree management along a climate gradient in Ghana.

Issaka Abdulai,Sophie Graefe,Laurence Jassogne,Philippe Vaast,Piet Van Asten,Richard Asare,Peter Läderach,Claire Quinn

doi:10.1371/journal.pone.0195777

Abstract

Reduced climatic suitability due to climate change in cocoa growing regions of Ghana is expected in the coming decades. This threatens farmers’ livelihood and the cocoa sector. Climate change adaptation requires an improved understanding of existing cocoa production systems and farmers’ coping strategies. This study characterized current cocoa production, income diversification and shade tree management along a climate gradient within the cocoa belt of Ghana. The objectives were to 1) compare existing production and income diversification between dry, mid and wet climatic regions, and 2) identify shade trees in cocoa agroforestry systems and their distribution along the climatic gradient. Our results showed that current mean cocoa yield level of 288kg ha-1yr-1 in the dry region was significantly lower than in the mid and wet regions with mean yields of 712 and 849 kg ha-1 yr-1, respectively. In the dry region, farmers diversified their income sources with non-cocoa crops and off-farm activities while farmers at the mid and wet regions mainly depended on cocoa (over 80% of annual income). Two shade systems classified as medium and low shade cocoa agroforestry systems were identified across the studied regions. The medium shade system was more abundant in the dry region and associated to adaptation to marginal climatic conditions. The low shade system showed significantly higher yield in the wet region but no difference was observed between the mid and dry regions. This study highlights the need for optimum shade level recommendation to be climatic region specific.

Highlights

Ghana is the second largest global cocoa producer with an estimated US$ 2 billion generated by export revenues in 2013 [1]
Different types of climate change adaptation including incremental, systemic and transformative adaptation would be required at different locations within the cocoa belt of West Africa depending on the projected climatic changes [9]
The regions were differentiated by the cocoa farm land use history (Fig 2) with the dry region dominated by farms having been previously used for cocoa, but with a short fallow combined with annual crops such as maize and vegetables in-between cocoa cycles

Summary

Introduction

Ghana is the second largest global cocoa producer with an estimated US$ 2 billion generated by export revenues in 2013 [1]. Cote d’Ivoire, the world largest cocoa producer, has experienced a similar shift with such extreme climate event being a contributing factor to geographic shifts in production areas [8]. Such spatial and temporal variations in climatic events allow for the identification of farmers responses to climate change [4,8,9]. A lack of available forest land for new cocoa farms in the wet regions and the potentially negative effects of climate change are foreseen as being part of the major constraints to sustainable production growth in the coming years [12,13]

Objectives

Methods

Results

Conclusion