Trace elements (TEs) in soil solutions play a vital role in monitoring environmental health, nutrient availability, and contaminant mobility. However, accurately sampling these solutions using a lysimeter requires materials that do not leach or adsorb TEs, which has been a persistent challenge with traditional materials such as stainless steel and ceramic. This study evaluated the suitability of porous (10 µm) polyethylene for lysimeter construction and examined the spatial and temporal distribution of TEs in soils in Elmvale, Ontario.

Polyethylene lysimeters were cleaned and tested to establish blank TE values, deployed in the field at shallow (0-15 cm) and deep (15-30 cm) depths, and used to sample soil solutions over multiple dates and locations (nests). Concentration of trace elements in soil solutions were analyzed using advanced spectroscopy techniques.  

Using Principal Component Analysis (PCA) and correlation analysis, we examined the concentrations to identify patterns associated with site-specific characteristics and temporal variations. Correlation analysis indicate significant associations between certain elements and environmental factors, suggesting that TEs with similar chemical properties tend to display distinct mobility patterns.

The concentration of dissolved TEs in soil solutions were much higher compared to the blank (deionized water) values, with ratios ranging from 17 times for Molybdenum to 2,900 times for Lanthanum. This implies that the metal-free lysimeter is a reliable tool for collecting soil solutions without significant contamination, enabling accurate measurement of TE concentrations. Furthermore, the patterns on spatial and temporal distribution of TEs in Elmvale, Ontario, has provided valuable insights into their mobility and sources, contributing to better management of soil and water resources.