* Mirova to pick projects in Africa, LatAm, Asia

* To invest $10-$20 mln each in up to 20 projects

* To invest for up to 10 years; NGO to track impact

LONDON, June 6 (Reuters) - Asset manager Mirova and the non-profit Rainforest Alliance have signed an agreement to scale up regenerative agriculture and sustainable land use projects across Africa, Latin America and Asia, executives told Reuters.

Mirova, a sustainability-focused unit of French investor Natixis Investment Managers, said funding for the projects would come from its previously announced Mirova Sustainable Land Fund 2 fund, which aims to raise 350 million euros ($381 million).

The tie-up comes as policymakers across the world tighten rules governing companies' supply chains as part of efforts to combat climate change and protect and restore biodiversity loss.

Doing so is increasingly important for the world's biggest companies as the health of the land needed to produce key crops such as coffee and cocoa is under threat.

"If agriculture doesn't begin to restore the health in the soils, by 2050, 50% of the land for coffee will be gone," said Rainforest Alliance Chief Executive Santiago Gowland.

"Regenerative agriculture is good for the producer, good for the market, good for the investor ... so funding that transition unlocks value for all."

Drawing on the Rainforest Alliance's local presence, Mirova will pick around 10-20 projects in which it can invest up to $20 million, said Mirova Deputy Chief Executive and Head of Private Equity and Natural Capital Anne-Laurence Roucher.

As well as the planetary benefit of helping companies adopt regenerative agriculture, the companies will be able to sell resulting products for a premium by being able to prove the higher quality production processes.

Additional revenues could come from selling carbon credits for sequestering carbon emissions, all of which would help close a finance gap that has seen such projects only secure a third of the money needed by 2030, Gowland said.

The fund would invest in equity or debt for up to 10 years to give the companies time to transition and Rainforest Alliance would track the environmental impact of the projects.

($1 = 0.9188 euros) (Editing by Mark Potter)