COCOA’S COMRADES

 The researchers aimed to answer a string of questions: how carbon stocks of cocoa agroforests varied across ecological zones and management methods; how carbon storage compared between different types of plants associated with cocoa – and the stocks of some key species, in particular.

“What we found is that agroforests with a high density of high-economic value industrial timber and non-timber forest products stored two to three times the amount captured by other management systems,” explains Sonwa.

Plantations with a high density of banana plants and oil palm trees came next, and those with cocoa tree densities of 70% or higher came in last. Specifically, the above-ground parts of plants in these varied types of cocoa agroforests stored 147 Mg of carbon per hectare, 49 Mg and 39 Mg, respectively.

Researchers also found that above-ground parts of the other plants accounted for 70% of the carbon storage, while cocoa trees accounted for only 5%.

Across all three ecological zones, high-value timber accounts for 29.7% of the total carbon stored above ground, at 49.9 Mg per hectare; edible species for 15%; and medicinal plants for 6%.

RICH PICKINGS

Another conclusion of the study is that “the top ten species generally stored more than 50% of carbon held by associated plants,” with Terminalia superba – a tall deciduous tree native to the African tropics – among the species with a higher storage (14 Mg per hectare).

Analysis

Agroforestry: Why don’t farmers plant more trees?

These results “suggest that associated plants not only contribute to shade, but also increase the capacity of farms to store carbon,” notes the study. And the benefits of such plants go well beyond that. Indeed, the higher eco-capacity of cocoa agroforests lead to increases in plant litter fall, soil litter and rainfall, thus upgrading both the agronomic and environmental potential of the landscape. Meanwhile, a plantation solely growing cocoa does threaten the overall agro-ecological sustainability.

Sonwa points out that non-cocoa plants provide a structure similar to that of forests, and that their products and services appear as co-benefits of cocoa agroforestry in addition to carbon storage. Timber, non-wood forest products such as fruit, and medicinal plants may all contribute to local livelihoods and to biodiversity conservation.

“Simultaneously obtaining several products and services from the same plantation increases the resilience of farmers,” he says. “That is particularly important as the pressure on natural resources increases.”

BEYOND THE BEANS

In the last few decades, the main goal of cocoa agroforests was to produce cocoa beans, but demographic growth, climate change and loss of forests are changing this approach.

For the researchers, the multiple functions of cocoa agroforests should be at the center of efforts to fight global warming and achieve better outcomes for people and the planet. “This is why our findings are useful to scientists, and also to decision-makers, farmers and the private sector,” says Sonwa.

Analysis

The forests of Central Africa: A source of wealth to be rediscovered

The findings of the paper can, for example, be useful to certification schemes that want to improve the environmental footprint of the cocoa sector. They also offer key insights to cocoa agroforest managers, particularly given the current context where zero deforestation targets are at the center of many company agendas.

In Sub-Saharan Africa where most of the global cocoa originates, the paper is certainly useful in structuring efforts to free the cocoa value chain from deforestation. But going beyond that, in central Africa and the Congo Basin, it sheds light by offering productive agroforestry options that conserve the remaining natural forests while providing livelihoods.

“We have examined cocoa agroforests from an ecological perspective, so the next step would be to look at economic and production aspects,” says Sonwa. “For example, does storing more carbon in associated plants affect cocoa production – and how?”

The findings make clear that sustainable cocoa agroforest management in Sub-Saharan African forest landscapes can reconcile cocoa bean production with climate change responses, and big global initiatives, such as the SDGs.

But, it also makes clear how much there is left to learn about chocolate.