Free-draining lysimeters containing a soil monolith are widely applied in studying the environmental fate of chemicals. In order to compare lysimeter data to the field scale, an extensive experiment was set up consisting of a 1-ha experimental field plot with 30 suction plates installed at 1.2 m depth and six lysimeters 1.2 m in height. The leachate in the field was obtained using tensiometer-controlled ceramic plates. In addition to a mobile and an immobile test substance for determining mass transport, bromide was used as a water tracer over the test period. Larger leachate amounts were observed in the lysimeters, which resulted in a faster movement at the time scale in the case of bromide. The bromide recoveries for both systems were the same. The lysimeters had a slightly lower effective mean pore water velocity and a higher solute spreading than the suction plates. The spatial variability in hydraulic properties explained the observed variability and differences in cumulative leachate, at least quantitatively. The size of the lysimeters was large enough to cover the soil heterogeneity of the field plot. In contrast to the field, high concentrations of both test compounds were analyzed in the leachate of the lysimeter.
See more of Symposium--Water and Chemical Fluxes from the Pore to Landscape Scale: III
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