The term “agroforestry” refers to land-use systems characterised by the management and integration of woody perennials (like trees and shrubs), agricultural crops and/or livestock on the same plot of lands. The three main types of agroforestry systems are indeed:
- Agri-silvicultural systems, which combine crops with trees;
- Silvopastoral systems, a combination of forestry and pastures for livestock;
- Agrosylvopastoral systems, which integrate three components, i.e. trees, animals and crops.
As opposed to traditional forestry and agriculture practices, agroforestry systems are dynamic and they focus on the ecological and economical interactions among the different components. The integration of trees, crops and/or livestock plays a key role in sustaining a diversified production, which benefits land users at all levels, from a social, economic and environmental perspective.
The cocoa tree, Theobroma cacao, is a small evergreen tree, native to the tropical regions of Mesoamerica, where it naturally grows beneath large tropical tree canopies in low light and high humidity conditions. These characteristics enable cocoa trees to thrive in fully or partially shaded conditions in agroforestry systems; despite this, cocoa monocultures are still a widespread reality.
This farming practice leads to higher yields in the short-term, but quickly causes ecosystem properties impoverishment, including degradation and dry up of soil, and nutrients loss. External inputs, like water, fertilisers and pesticides, become necessary in great quantity in order to maintain high yields in the long term. Considering that cocoa is often cultivated in small-holder farms, it is usually more convenient to cut down forest in new areas to make way for more cocoa monocultures. In this way, the short-term profitability is maximised at the expense of the environment. Monocultures are therefore a non-sustainable farming practice over the long-term, especially for small-holder farmers; it is also among the main causes of soil erosion, deforestation and biodiversity loss, which increases the vulnerability of the cocoa trees to pests and diseases, as well as to the impacts of climate change. On the opposite, agroforestry systems, like cocoa ones, are multi-functional systems that can provide several environmental, social and economic benefits.
Cocoa agroforestry systems can indeed contribute to enhance biodiversity, reduce soil erosion and show a better resilience to extreme events, like strong winds, high temperatures, intensive rainfall and floods. The shade tree species in cocoa agroforestry systems also help filter access to light, store water and nutrients and modify microclimatic conditions, like temperature and air water vapour content. The selection of adequate and different tree species plays also an important role in enhancing weed, pest and disease control: the increased availability of soil organic matter contributes to reducing the need for pesticides, herbicides and fertilisers.
From an economic point of view, cocoa agroforestry systems can improve yields on longer life-cycle and lead to more stable and diversified incomes, since productive shade trees can be useful for a wide range of products, like food, timber, fuel, etc.
Eventually, cocoa agroforestry systems have also a key role in climate change mitigation: the greater the number and size of shade trees, the greater the carbon stocks, thereby reducing the environmental footprint of agriculture compared to traditional farming practices.
Cocoa pods (© DR Cocoa Foundation, 2020)