title: Ecosystem Composition Controls the Fate of Rare Earth Elements during Incipient Soil Genesis.
abstract: The rare earth elements (REE) are increasingly important in a variety of science and economic fields, including (bio)geosciences, paleoecology, astrobiology, and mining. However, REE distribution in early rock-microbe-plant systems has remained elusive. We tested the hypothesis that REE mass-partitioning during incipient weathering of basalt, rhyolite, granite and schist depends on the activity of microbes, vascular plants (Buffalo grass), and arbuscular mycorrhiza. Pore-water element abundances revealed a rapid transition from abiotic to biotic signatures of weathering, the latter associated with smaller aqueous loss and larger plant uptake. Abiotic dissolution was 39% of total denudation in plant-microbes-mycorrhiza treatment. Microbes incremented denudation, particularly in rhyolite, and this resulted in decreased bioavailable solid pools in this rock. Total mobilization (aqueous + uptake) was ten times greater in planted compared to abiotic treatments, REE masses in plant generally exceeding those in water. Larger plants increased bioavailable solid pools, consistent with enhanced soil genesis. Mycorrhiza generally had a positive effect on total mobilization. The main mechanism behind incipient REE weathering was carbonation enhanced by biotic respiration, the denudation patterns being largely dictated by mineralogy. A consistent biotic signature was observed in La:phosphate and mobilization: solid pool ratios, and in the pattern of denudation and uptake.
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.
authors.forename: Dragos G
authors.initials: DG
authors.lastname: Zaharescu
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.
authors.forename: Carmen I
authors.initials: CI
authors.lastname: Burghelea
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.|Department of Soil, Water &Environmental Science, The University of Arizona, Tucson, AZ, USA.
authors.forename: Katerina
authors.initials: K
authors.lastname: Dontsova
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Presler
authors.affiliation: Department of Soil, Water &Environmental Science, The University of Arizona, Tucson, AZ, USA.
authors.forename: Raina M
authors.initials: RM
authors.lastname: Maier
authors.affiliation: School of Biological Sciences, University of California, Irvine, CA, USA.
authors.forename: Travis
authors.initials: T
authors.lastname: Huxman
authors.affiliation: Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ, USA.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Domanik
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.
authors.forename: Edward A
authors.initials: EA
authors.lastname: Hunt
authors.affiliation: Department of Soil, Water &Environmental Science, The University of Arizona, Tucson, AZ, USA.|Arizona Laboratory for Emerging Contaminants, The University of Arizona, Tucson, AZ, USA.
authors.forename: Mary K
authors.initials: MK
authors.lastname: Amistadi
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.|Williams College, Williamstown, MA, USA.
authors.forename: Emily E
authors.initials: EE
authors.lastname: Gaddis
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.|The University of Caribe, Cancún, México.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Palacios-Menendez
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.|University of the Americas Puebla, Puebla, México.
authors.forename: Maria O
authors.initials: MO
authors.lastname: Vaquera-Ibarra
authors.affiliation: Biosphere 2, The University of Arizona, Tucson, AZ, USA.|Department of Soil, Water &Environmental Science, The University of Arizona, Tucson, AZ, USA.
authors.forename: Jon
authors.initials: J
authors.lastname: Chorover
mesh_terms: D017753:Ecosystem; D008660:Metabolism; D008674:Metals, Rare Earth / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*
chemical_list: D008674:Metals, Rare Earth; D012987:Soil