Carbonate dissolution cones are unlikely to originate from stemflow funneling

Over geologic timescales, forests have intercepted precipitation and thereby modified the intensity, duration, and spatial patterns of water fluxes to forest soils. Across a range of environmental conditions, persistent focused water flows can dissolve carbonate substrates, and form conical dissolution features—termed “dissolution cones.” These cones generally fill with soils, becoming localized soil (and water) reservoirs occupied by vegetation. A myriad of mechanisms are hypothesized to have formed dissolution cones. Prior work has sought to explain co-located palm trees and modern dissolution cones in tropical unconsolidated carbonates as the result of the chemical action of weakly acidic stemflow funneled by palm canopies down their stems, and into the substrate. Using a geochemical modeling program, PHREEQC, we find that for a range of environmental conditions and favorable assumptions, stemflow is unable to dissolve a benchmark volume of carbonate substrate that typifies tropical dissolution cones. Therefore, dissolution cone formation by abiotic dissolution from stemflow funneling is unlikely to be the chief geomorphic process. Further hypotheses to be tested are discussed.