Benedicta Ronchi

Landscape cultivation alters delta Si-30 signature in terrestrial ecosystems

Despite increasing recognition of the relevance of biological cycling for Si cycling in ecosystems and for Si export from soils to fluvial systems, effects of human cultivation on the Si cycle are still relatively understudied. Here we examined stable Si isotope (δ30Si) signatures in soil water samples across a temperate land use gradient. We show that – independent of geological and climatological variation – there is a depletion in light isotopes in soil water of intensive croplands and managed grasslands relative to native forests. Furthermore, our data suggest a divergence in δ30Si signatures along the land use change gradient, highlighting the imprint of vegetation cover, human cultivation and intensity of disturbance on δ30Si patterns, on top of more conventionally acknowledged drivers (i.e. mineralogy and climate).

Transport of Dissolved Si from Soil to River: A Conceptual Mechanistic Model

This paper reviews the processes which determine the concentrations of dissolved silicon (DSi) in soil water and proposes a conceptual mechanistic model for understanding the transport of Si through soils to rivers. The net DSi present in natural waters originates from the dissolution of mineral and amorphous Si sources in the soil, as well as precipitation processes. Important controlling factors are soil composition (mineralogy and saturated porosity) and soil water chemistry (pH, concentrations of organic acids, CO2 and electrolytes). Together with production, polymerization and adsorption equations they constitute a mechanistic framework determining DSi concentrations. We discuss how key controls differ across soil horizons and how this can influence the DSi transport. A typical podzol soil profile in a temperate climate is used as an example, but the proposed model is transferrable to other soil types. Additionally, the impact of external forcing factors such as seasonal climatic variations and land use is evaluated. This blueprint for an integrated model is a first step to mechanistic modelling of Si transport processes in soils. Future implementation with numerical methods should validate the model with field measurements.

Erratum: CORRIGENDUM: Landscape cultivation alters δ30Si signature in terrestrial ecosystems

Scientific Reports 5, Article number: 7732 10.1038/srep07732 (2015); Published: January132015; Updated: March152015 Jean-Thomas Cornelis was included in the Acknowledgements but omitted from the author list in the original version of this Article. This has been corrected in the PDF and HTML versions of the Article and in the Supplementary Information. Acknowledgements “F.I.V. thanks Special Research Funding of the University of Antwerp (BOF-UA) for PhD fellowship funding and Patrick Frings, Ryan Taylor and Jean-Thomas Cornelis for proof-reading and editing the manuscript. We also acknowledge Flemish Science Foundation (FWO) for funding the project “Tracking the biological control on Si mobilisation in upland ecosystems” (project number G014609N).” Now reads “F.I.V. thanks Special Research Funding of the University of Antwerp (BOF-UA) for PhD fellowship funding and Patrick Frings and Ryan Taylor for editing the manuscript as native speakers. We also acknowledge Flemish Science Foundation (FWO) for funding the project “Tracking the biological control on Si mobilisation in upland ecosystems” (project number G014609N) and BELSPO for funding the project SOGLO.” Author contributions “F.I.V. collected the samples and wrote the first drafts. C.D. and H.H. optimised and developed the isotopic analytical method, analysed the samples, made the data processing, and co-developed the discussion. F.I.V., W.C., E.S., G.G. and B.R. were involved in site selection and/or installation of the land use gradient. B.R. and A.L.B. provided background data on clay analysis and Si fractions in the soil. P.M., E.S., L.A. and G.G. initialised and conceptualised the work on Si biogeochemistry in joint collaborations. All authors contributed to the writing and methodological development of the paper.” Now reads “F.I.V. collected the samples and wrote the first drafts. C.D. and H.H. optimised and developed the isotopic analytical method, analysed the samples, made the data processing, and C.D., H.H. and J-T C. co-developed the discussion. F.I.V., W.C., E.S., G.G. and B.R. were involved in site selection and/or installation of the land use gradient. B.R. and A.L.B. provided background data on clay analysis and Si fractions in the soil. P.M., E.S., L.A. and G.G. initialised and conceptualised the work on Si biogeochemistry in joint collaborations. All authors contributed to the writing and methodological development of the paper.” The original Article contained an error in the calculation of the weathering index Total Reserve in Bases (TRB) in figure 2b. The correct figure 2 appears below as Figure 1. Figure 1 (a) Scatterplot of biogenic silica (BSi) in mg g−1 dry soil in the soil profile, (b) Total Reserve in Bases (TRB = [Na] + [Mg] + [Ca] + [K]) weathering index calculated on dry soil, in cmol charge kg−1. Sites are represented by symbols: ...

CORRIGENDUM: Landscape cultivation alters δ30Si signature in terrestrial ecosystems

Scientific Reports 5, Article number: 7732 10.1038/srep07732 (2015); Published: January132015; Updated: March152015 Jean-Thomas Cornelis was included in the Acknowledgements but omitted from the author list in the original version of this Article. This has been corrected in the PDF and HTML versions of the Article and in the Supplementary Information. Acknowledgements “F.I.V. thanks Special Research Funding of the University of Antwerp (BOF-UA) for PhD fellowship funding and Patrick Frings, Ryan Taylor and Jean-Thomas Cornelis for proof-reading and editing the manuscript. We also acknowledge Flemish Science Foundation (FWO) for funding the project “Tracking the biological control on Si mobilisation in upland ecosystems” (project number G014609N).” Now reads “F.I.V. thanks Special Research Funding of the University of Antwerp (BOF-UA) for PhD fellowship funding and Patrick Frings and Ryan Taylor for editing the manuscript as native speakers. We also acknowledge Flemish Science Foundation (FWO) for funding the project “Tracking the biological control on Si mobilisation in upland ecosystems” (project number G014609N) and BELSPO for funding the project SOGLO.” Author contributions “F.I.V. collected the samples and wrote the first drafts. C.D. and H.H. optimised and developed the isotopic analytical method, analysed the samples, made the data processing, and co-developed the discussion. F.I.V., W.C., E.S., G.G. and B.R. were involved in site selection and/or installation of the land use gradient. B.R. and A.L.B. provided background data on clay analysis and Si fractions in the soil. P.M., E.S., L.A. and G.G. initialised and conceptualised the work on Si biogeochemistry in joint collaborations. All authors contributed to the writing and methodological development of the paper.” Now reads “F.I.V. collected the samples and wrote the first drafts. C.D. and H.H. optimised and developed the isotopic analytical method, analysed the samples, made the data processing, and C.D., H.H. and J-T C. co-developed the discussion. F.I.V., W.C., E.S., G.G. and B.R. were involved in site selection and/or installation of the land use gradient. B.R. and A.L.B. provided background data on clay analysis and Si fractions in the soil. P.M., E.S., L.A. and G.G. initialised and conceptualised the work on Si biogeochemistry in joint collaborations. All authors contributed to the writing and methodological development of the paper.” The original Article contained an error in the calculation of the weathering index Total Reserve in Bases (TRB) in figure 2b. The correct figure 2 appears below as Figure 1. Figure 1 (a) Scatterplot of biogenic silica (BSi) in mg g−1 dry soil in the soil profile, (b) Total Reserve in Bases (TRB = [Na] + [Mg] + [Ca] + [K]) weathering index calculated on dry soil, in cmol charge kg−1. Sites are represented by symbols: ...