Atmospheric mineral dust is a well-established source of nutrients to marine ecosystems,
yet its contribution to terrestrial plant nutrition has long been underestimated, largely due to
the assumption that nutrient acquisition occurs predominantly through root uptake from
soils. Here, we present evidence from controlled greenhouse experiments under ambient
and elevated CO₂, laboratory simulations of leaf microenvironments, isotopic and
geochemical tracing, and field fertilization experiments conducted in both a Mediterranean
ecosystem and a tropical forest in Puerto Rico, demonstrating that plants can directly
acquire nutrients through their leaf surfaces following atmospheric dust deposition. Using
rare earth elements and Nd isotopes, we distinguish nutrients derived from soils from those
delivered by deposited atmospheric particles. Laboratory simulations show that mildly
acidic leaf surfaces, together with organic acids secreted by leaves, enhance mineral
dissolution and facilitate foliar uptake of dust-borne nutrients. In a pioneering Mediterranean
field experiment explicitly designed to isolate foliar uptake, we quantified the bioavailable
fraction of key nutrients supplied by dust, including P, Fe, Mn, and Cu, and observed clear
enrichment of multiple micronutrients in leaf tissues following dust application. These fieldbased
measurements enabled the construction of a global geospatial framework integrating
dust deposition with soil nutrient fluxes, indicating that dust-derived inputs can constitute a
meaningful fraction of total nutrient supply across large regions, and that during dust
events, short-term foliar inputs can rival or exceed soil-derived fluxes. Complementary field
observations in a tropical forest in Puerto Rico further reveal foliar nutrient responses
consistent with direct dust uptake. Building on these results, we outline a pathway for
incorporating foliar dust uptake into Earth system representations of terrestrial nutrient
cycling by explicitly accounting for atmospheric nutrient inputs at the canopy level and their
interaction with soil-derived fluxes. Together, these findings identify foliar dust uptake as an
overlooked but consequential nutrient acquisition pathway and highlight its relevance in
highly weathered, nutrient-limited tropical forests, where atmospheric inputs may play a
critical role in regulating nutrient availability and carbon–nutrient interactions.
SUMMARY:Atmospheric dust is a global nutrient source for plants via foliar uptake END:VEVENT END:VCALENDAR