THE UPLIFT OF SOIL NUTRIENTS BY PLANTS: BIOGEOCHEMICAL CONSEQUENCES ACROSS SCALES

Although the bulk of plant biomass contains relatively light, atmospherically derived elements (C, H, O, N, and S), 5–10% of biomass is composed of heavier elements from soil minerals, such as Ca, Mg, K, and P. Plant uptake and cycling transport these heavier elements to the soil surface, resulting in shallower vertical distributions for strongly cycled elements than for other elements. In this paper, we evaluate the biogeochemical consequences of this process at different spatial and temporal scales based on chronosequence studies and soil database analyses. In the bare coastal dunes of Argentina, the vertical distributions of exchangeable K+ (strongly cycled) and Na+ (more weakly cycled) were similar…