Coupled transport, fractionation and stabilization of dissolved organic matter and rare earth elements in the critical zone

摘要: It is important to understand the processes that influence critical zone (CZ) evolution ensure its sustainability. This thesis reports on laboratory and field experiments designed measure behavior of biogenic lithogenic chemical species their interaction in CZ from column pedon catchment scales. We postulated interactions between organic matter rock-derived metals drive coupled carbon stabilization weathering denudation Jemez River Basin Critical Zone Observatory (JRB-CZO). First, we observed secondary mineral coatings (Al Fe (oxy)hydroxides) primary silicate surfaces play a major role sequestering aromatic “humified” dissolved (DOM) into sorbate form, significantly retarding subsurface transport. Further, reinfusion OM-reacted-porous-media different DOM source resulted exchange reactions consistent with zonal model OM adsorption at surfaces. dissertation also aimed examine water fluxes processes. Rare earth elements (REE) were selected because coherent trends reactivity toward ligands common soils. Specifically, REE fractionation explored for utility inform biogeochemical forested terrain JRB-CZO. Mineral mechanisms are expected differentially release, fractionation, transport relative importance such should be reflected signatures bulk soil, pore surface waters. Our studies showed: (1) depletion depth soils correlated topographically-induced variation