Global Agroforestry Network

Pollination Services for Sustainable Cocoa

Agroforests and Ecosystem Services

Cocoa is one of the most important traded commodities globally, and its production is strongly affected by weather fluctuations associated to climate change. Land use expansion of cocoa monocultures and agrochemical intensification have been the main strategy to mitigate climate-related yield deficits. This expansion provides significant economic earnings for stakeholders, but at the cost of pristine forest, and the overall environment stability.

Stakeholders and decision makers increasingly realize that diverse agroforests provide a ‘green’ development trajectory that can enhance ecosystem services and balance better development and conservation goals in an uncertain environment. Cocoa pollination has recently been shown to increase yields in resilient agroforestry systems and to increase rural livelihoods. If these pollination benefits remain stable over a long time and can be implemented at scale, high yielding and climate smart agroforestry systems with rural livelihood benefits may offer a viable alternative to vulnerable monoculture cocoa production systems.

Our Work

We aim to address a key research gap of understanding long-term effects of established agroforestry landscapes on yield stability and cocoa pollination benefits in world leading producing countries Brazil, Cameroon, Ghana and Indonesia.

Brazil

Farm diversification and pollination services

Our research in traditional cocoa agroforests, or cabrucas, in the region of Bahia aims to highlight the potential of diversified landscapes for biodiversity conservation and ecosystem services provision. We combine natural and manual pollination approaches to understand how pollination enhancement can shorten yield gaps in agroforestry systems. Other research partners conduct long-term soil carbon sequestration, and biodiversity monitoring of mammals, birds, amphibians & reptiles in cabruca systems.

Collaborators:

Dr. Manuel Toledo-Hernández - Westlake University

Prof. Thomas C. Wanger - Westlake University

Prof. Mirco Solé - Universidade Estadual de Santa Cruz

Christian Wolff - AMAP

Cameroon

Reveal the pollinator identity with metabarcoding

In our research in Cameroonian tropical forest landscapes, we aim to understand the trade-offs and synergies of pollination and other ecosystem services in cocoa agroforests. To address these questions we apply molecular biology, ecological modelling, and sociological approaches. One of our major challenges is to reveal the identity tiny cocoa pollinators using metabarcoding and environmental DNA protocols.

Collaborators:

Alma Liss Sánchez Quiñones - Durham University

Dr. Andreanna J. Welch - Durham University

Dr. Luke Powell - University of Glasgow

Prof. Thomas C. Wanger - Westlake University

Ghana

Plant physiology and pollination services

In Western region of Ghana, we investigate the relative limitations of pollination services and plant physiological capacity for improving yields sustainably. Our aim is to understand how cauliflory (fruit and flower growth from woody stem/branches) and self-thinning (premature fruit abortion) adaptations in cocoa enhance pollination service and allocation efficiency, respectively. Parallel experiments focus on quantifying cocoa pollinator diversity and abundance.

Collaborators:

Acheampong Atta-Boateng - University of Oxford

Prof. Yadvinder Malhi - University of Oxford

Dr. Tonya Lander - University of Oxford

Prof. Thomas C. Wanger - Westlake University

Indonesia

Plant physiology and pollination services

Our work in Central Sulawesi, the major producing region in Indonesia, aims to disentangle the overall role of pollination services for securing yields and farmer livelihoods. We quantify yield stability and socioeconomic benefits of large manual pollination across time. We also develop an insect monitoring device using an AI-software that records real-time pollinators. This helps on tracking breeding habitats and provide recommendations for enhancing pollination services.

Collaborators:

Dr. Manuel Toledo-Hernández - Westlake University

Dr. Kevin Darras - Westlake University

Prof. Thomas C. Wanger - Westlake University

Prof. Teja Tscharntke - University of Goettingen

Dr. Aiyen Tjoa - Tadulako University

Publications and Press

Published

Toledo-Hernández, M., Atta-Boateng, A., Xie, K., Lander. T, Wanger TC. 2021. Bridging the implementation gap of gene-edited crops. Trends in Ecology and Evolution.
Toledo-Hernández, M., Tscharntke, T., Tjoa, A., Anshary, A., Cyio, B., Wanger, T. C. 2021. Landscape and farm-level management for pollinator conservation in Indonesian cocoa agroforests. Biological Conservation. Full text available here
Toledo-Hernández, M., Tscharntke, T., Tjoa, A., Anshary, A., Cyio, B., Wanger, T. C. 2020. Hand pollination, not pesticides or fertilizers, increases cocoa yields and farmer income. Agriculture, Ecosystems & Environment 304, 107160. Full text available here
Wanger, T.C., Hölscher, D., Veldkamp, E., Tscharntke, T. 2018. Cocoa production: Monocultures are not the solution to climate adaptation—Response to Abdulai et al. 2017." Global Change Biology 24, 561-562. Request text here
Toledo-Hernández, M., Wanger, T.C, Tscharntke, T. 2017. Neglected pollinators: Can enhanced pollination services improve cocoa yields? A review. Agriculture, Ecosystems & Environment 247, 137-148. Full text available here
Wanger, T.C., Schroth, G., Klein, A-M., Tscharntke, T., 2014. Pollination curbs climate risk to cocoa. Nature 511, 155. Full text available here
Tscharntke, T., Clough, Y., Bhagwat, S-A., Buchori, D., Faust, H., Hertel, D., Hölscher, D., Juhrbandt, J., Kessler, M., Perfecto, I., Scherber, C., Schroth, G., Veldkamp, E., Wanger, T.C. 2011. Multifunctional Shade-Tree Management in Tropical Agroforestry Landscapes–a Review. Journal of Applied Ecology 48, 619–629. Full text available here

Submitted or in preparation

Atta-Boateng, A., Toledo-Hernández, M., Wanger T.C., Berlyn,0 G.P., Lander, T. Differences in cacao yield gaps across growing regions: evidence and opportunities. In Prep.
Atta-Boateng, A., Toledo-Hernández, M. ,Quiñones, A-L, Yan Yan, Darras, K., Wanger, T.C. Simplifying sustainability concepts: the case of cross-stakeholder implementation challenges in agriculture.
Quiñones, A. L., Powell, L., Wagner, T.C., Welch, A.J. Methodological trends in the assessment and improvement of Ecosystem Services in cacao agroforestry: A systematic review. In prep.
Wanger, T.C., Dennig, F., Toledo-Hernández, M., Tscharnkte, T., Lambin, E. Solving the global cocoa crisis with pollination – a global perspective. In prep.