Effects of soil wetness and tyre pressure on soil physical quality and maize growth by a slurry spreader system

•Soil wetness and tyre pressure were sensitive to tyre-soil contact mean ground pressure.•X-ray micro-CT precisely quantify soil macro-pore structure changes.•Compaction risks from tractor-slurry combination was overrated by Terranimo® model.•Topsoil ploughing was not sufficient to eradicate negative compaction effects on maize biomass.•Maize yield was 7% lower inside slurry tracks than outside. Slurry spreaders are among the heaviest machines used for farming operations. The effects of soil wetness and tyre pressure on physical soil properties were evaluated by using a ˜5 Mg wheel load slurry spreader mounted on a tractor. The impacts were also compared with Terranimo® model predictions and X-ray micro-computed tomography (X-ray micro-CT) parameters. In the consecutive maize growing season, soil physical properties, total mineral nitrogen content and maize above biomass were evaluated additionally between in and out track positions. Immediately after traffic, penetration resistance (PR) was significantly higher (P 30 μm) of soil trafficked under moist conditions was different (P ≤ 0.10) from those under dry conditions. Macro-porosity showed a clear response (P 0.05) between in- and out-track positions while above ground dry biomass of maize reduced with ˜7% at in-track positions.