Understanding contaminant transport through unsaturated porous media is a considerable challenge, given the complex interplay of nonlinear physical and biogeochemical processes driven by variations in water saturation. In this study, we tackled this challenge through a series of column experiments involving fine (100-300 μm) and coarse (1.0-1.
View Article and Find Full Text PDFEnviron Sci Technol
February 2023
Iron oxyhydroxide nanoparticle reactivity has been widely investigated, yet little is still known on how particle aggregation controls the mobility and transport of environmental compounds. Here, we examine how aggregates of goethite (α-FeOOH) nanoparticle deposited on 100-300 μm quartz particles (GCS) alter the transport of two emerging contaminants and two naturally occurring inorganic ligands-silicates and phosphates. Bromide tracer experiments showed no water fractionation into mobile and immobile water zones in an individual goethite-coated sand (GCS) column, whereas around 10% of the total water was immobile in a GCS column.
View Article and Find Full Text PDFIn recent decades, stormwater management has developed to allow stormwater to infiltrate directly into the soils instead of being collected and routed to sewer systems. However, during infiltration, stormwater creates a sediment deposit at the soil surface as the result of high loads of suspended particles (including pollutants), leading to the settlement of sedimentary layers prone to colonization by plants and earthworms. This study aims to investigate the earthworm communities of a peculiar infiltration basin and investigate the influence of edaphic conditions (water content, organic matter content, pH, height of sediment) and of persistent organic pollutants (POPs: PCBs, PCDDs and PCDFs) on these earthworms.
View Article and Find Full Text PDFUnderstanding linkages between heterogeneous soil structures and non-uniform flow is fundamental for interpreting infiltration processes and improving hydrological simulations. Here, we utilized ground-penetrating radar (GPR) as a non-invasive technique to investigate those linkages and to complement current traditional methods that are labor-intensive, invasive, and non-repeatable. We combined time-lapse GPR surveys with different types of infiltration experiments to create three-dimensional (3D) diagrams of the wetting dynamics.
View Article and Find Full Text PDFSci Total Environ
August 2020
Controlling soil erosion, especially in its initial stages, is greatly important in natural resources management. Consequently, the present research aimed to control splash and interrill erosion in two soil types (marl at Marzan-Abad and loess at Maraveh-Tapeh sites in northern Iran) using biochar (BC) and polyacrylamide (PAM). We established 0.
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