Mati Carbon and IITA launch five-year ERW field trials in Kenya and Nigeria

Mati Carbon has signed a five-year memorandum of understanding with the International Institute of Tropical Agriculture (IITA), committing the two organizations to joint enhanced rock weathering (ERW) field trials in Kenya and Nigeria. The partners inked the agreement at the COP31 conference in Antalya, Türkiye, and framed the collaboration as an attempt to generate performance evidence for ERW in African farming systems.

The deal matters because ERW credit markets currently rest on evidence gathered mostly outside the tropics. Under the MOU, Mati and IITA will cooperate on data sharing and analysis, scientific publication, capacity building with national research institutions, and joint fundraising. The trials themselves will evaluate the effects of crushed basalt spread on soil, measuring how the material affects soil health and crop growth.

What will the trials measure?

The field programs will test ERW performance alongside reduced synthetic fertilizer use, and the teams will work to identify the soil types and farm systems where the approach works best. That question of fit sits at the center of the agreement. The partners want an agronomic evidence base that indicates where ERW is a suitable agricultural intervention, evidence that would in turn inform research and policy decisions.

“Smallholder farmers are facing hotter seasons, longer dry spells, and fertilizer prices they cannot always afford. Rock dust could help on all three fronts, but that has to be shown in African fields first,” said John Choptiany, Resilience and Climate Adaptation Program Lead at IITA. He added: “These trials will tell us whether it can help farmers get more from every bag of fertilizer and keep their harvests steady when the weather turns against them.”

Where will the data go?

The trials will feed results into two CGIAR Science Programs, giving the collaboration an institutional pathway beyond the two signatories.

• CGIAR Sustainable Farming Program, which works with national partners in more than 20 countries to deliver integrated agronomy and soil health solutions to smallholder farmers, will connect the trial results to the advisory services that reach farmers in the field.
• CGIAR Climate Action Program will apply the generated evidence to help farming systems adapt to heat and drought and cut emissions, and will carry the findings into climate policy and finance decisions that follow.

That second channel links the agronomic work to the carbon market side of Mati's business. The company has already moved on the standards front: Mati Carbon was the first company to deliver credits under the new V1.2 ERW Isometric protocol, and it has previously announced a separate partnership on tropical ERW field trials. The IITA agreement extends that buildout into sub-Saharan Africa with a CGIAR research institution attached.

What does this change for ERW in Africa?

For now, it changes the evidence pipeline rather than the market itself. The five-year term signals that both parties expect multi-season data before conclusions hold; ERW performance depends on soil chemistry, climate and crop system, and none of that can be established from a single harvest. Kenya and Nigeria give the partners two large, climatically distinct trial grounds, and the national research institutions drawn in through the capacity-building track would carry the work beyond Mati's own sites.

The trials also test a proposition with direct cost implications for farmers: whether basalt applications allow reduced synthetic fertilizer use while sustaining yields. If the data support that combination, the Sustainable Farming Program's advisory network in more than 20 countries provides a distribution channel for the findings at smallholder scale.

The milestone to watch is the first tranche of published trial results. Until peer-reviewed data from Kenyan and Nigerian fields appear, the collaboration remains a commitment with a deadline — five years, counted from COP31 in Antalya — and the credibility of tropical ERW credits will continue to rest on evidence generated elsewhere.