PubMed · 2026-05-26
Researchers found that water content in plant leaves significantly skews readings from handheld X-ray scanners used to detect nutrients and heavy metals in the field, and they identified how to correct for this — making cheap, real-time plant analysis more reliable.
Water content caused a two-phase distortion: a steep drop in measured concentrations at low moisture levels, followed by a shallower decline as moisture increased further.
The inflection point where distortion behavior shifts depends on leaf thickness and the energy of the X-ray signal for each element — meaning different elements and plant species need different corrections.
Dilution by water accounts for most of the underestimation in fresh versus dried samples; spectral interference (signal cross-contamination) plays a larger role at lower moisture levels and diminishes as wetness increases.