LAUSR

Abstract Freshwater tropical wetlands are valuable sinks of carbon (C) on the global scale. While much attention has been paid to forested peatlands, little is known about C stored in tropical freshwater mineral soil wetlands dominated by herbaceous and macrophyte vegetation, specially its spatial variability at the ecosystem level. Here we study the soil organic carbon of two tropical lowland wetlands (fluvial and isolated), located in the interandean valley of the Magdalena river in Colombia. Soil cores were extracted from 11 sampling zones distributed in the two wetlands, including the dryland adjacent to each wetland. They were sectioned into 2 cm-depth increments that were analyzed for C content. The average bulk density was higher (P