Innovative reforestation mosaics on marginal land in the globally important Mata Atlântica biome can create climate and economic co-benefits

Tropical forests, such as Brazil's Mata Atlântica, provide extraordinary climate and socio-ecological services vital to planetary well-being. They are, nevertheless, disappearing because of soaring land-use competition, making reforestation essential. Plantation secondary-regrowth mosaics (PSRMs), which combine natural regeneration and commercial plantations for wood products on marginal lands with limited agricultural value, offer an innovative reforestation opportunity with potential climate and economic co-benefits. However, how and the extent to which such co-benefits can be made in Mata Atlântica remains unclear. By developing a multi-scale dynamic life cycle assessment framework, we show that, over 100 years, PSRMs for cross-laminated timber and biochar by fast-growing Eucalyptus with short rotation can offer the largest carbon sink (−33.8 GtCO2e) and highest returns (US $975-984 ha⁻¹ year⁻¹), outperforming secondary regrowth with a smaller carbon sink (−30.7 GtCO2e) and three-quarters fewer profits. PSRMs for pulp and paper can yield reasonable economic benefits but result in net emissions.