A Field Experiment for Tracing Lateral Subsurface Flow in a Post-Glacial Hummocky Arable Soil Landscape

Abstract

Lateral subsurface flow (LSF) is a phenomenon that is widely occurring including the hummocky ground moraine landscape. Due to the heterogeneous structure of the subsurface, transport times of pesticides and nutrients from agricultural areas to adjacent water bodies are difficult to assess. Here, LSF at Luvisol and Regosol plots of an experimental field were studied by applying potassium bromide along a 10 m trench below the plow pan in October 2019. The soil solution was collected in suction cups 3 m downslope of the trench and in April 2021, the soil was sampled down to 1 m depth. Almost no bromide was found in the soil solution except for the 160 cm depth of the Regosol plot after a 541 day period. After the same time, bromide was observed in the 90 cm soil depth directly underneath the application trench of the Luvisol plot. A 3D reconstruction of the subsurface horizon boundaries of the Regosol revealed subsurface heterogeneities such as sand lenses that might have been attributed to the heterogeneous subsurface flow pattern.

Exploring the Impact of Surface Functionalization on the Reaction, Magnetophoretic, and Collective Transport Behavior of Nanoscale Zerovalent Iron

“…Our motivation stems from the aspiration to develop an environmental cleaning technology by using nZVI as a nanoagent for degradation of pesticides and herbicides in soil. , We fully acknowledged that implementing magnetic capture in the field, particularly for large-scale in situ applications, presents significant challenges. Given the potential to track the lateral subsurface water flow, we envisage the possibility to capture the nZVI in the water stream from agriculture areas before it reaches the nearby water bodies. However, it is premature to delve into the engineering design of this hypothesis, given the unclear understanding of the complex interplay between magnetic capture, catalytic, transport, and colloidal behaviors of nZVI .…”