Dissolved silicon; Si transport; Mechanistic Si model; Land use; Amorphous Si
Abstract :
[en] This paper reviews the processes which determine the concentrations of dissolved silicon (DSi) in soil water and proposes a mechanistic model for understanding the transport of Si through a typical podzol soil to the river. DSi present in natural waters originates from the dissolution of mineral and amorphous Si sources in the soil. However, the DSi concentration in natural waters will be dependent on both dissolution and deposition/precipitation processes. The net DSi export is controlled by soil composition like (mineralogy and saturated porosity) as well as water composition (pH, concentrations of organic acids, CO2 and electrolytes). These state variables together with production, polymerization and adsorption equations constitute a mechanistic framework determining DSi concentrations. For a typical soil profile in a temperate climate, we discuss how the values of these key controls differ in each soil horizon and how it influences the DSi transport. Additionally, the impact of external forcings such as seasonal climatic variations and land use, is evaluated. This model is a first step to better understand Si transport processes in soils and should be further validated with field measurements.
Disciplines :
Geological, petroleum & mining engineering
Author, co-author :
Ronchi, Benedicta; Katholieke Universiteit Leuven - KUL > Earth and Environmental Sciences > Hydrogeologie
Vandevenne, Floor; University Antwerpen > Ecosystem Management Research Group, Department Biology
Pena Barao, Ana Lucia; University Antwerpen > Ecosystem Management Research Group, Department Biology
Clymans, Wim; Katholieke Universiteit Leuven - KUL > Earth and Environmental Sciences
Struyf, Eric; University Antwerpen > Ecosystem Management Research Group, Department Biology
Batelaan; Vrije Universiteit Brussel - VUB > Department of Hydrology and Hydraulic Engineering
Dassargues, Alain ; Université de Liège - ULiège > Département Argenco : Secteur GEO3 > Hydrogéologie & Géologie de l'environnement
Govers, Gérard; Katholieke Universiteit Leuven - KUL > Earth and Environmental Sciences
Language :
English
Title :
Transport of dissolved Si from soil to river: a conceptual mechanistic model
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