Abstract. Compaction and salinization of soils reduce croplands fertility, affect
natural ecosystems, and are major concerns worldwide. Soil compaction alters
soil structure and affects the soil's hydraulic properties, and it therefore
may have a significant impact on evaporation and solute transport processes
in the soil. In this work, we investigated the combined processes of soil
compaction, bare soil evaporation, and salt precipitation. X-ray computed
microtomography techniques were used to study the geometrical soil pore and
grain parameters influenced by compaction. The impact of compaction on
evaporation and salt precipitation was studied using column experiments. We
found that compaction reduced the average grain size and increased the
number of grains, due to the crushing of the grains and their translocation
within the compacted soil profile. Changes in pore and grain geometry and
size were heterogeneously distributed throughout the soil profile, with
changes most apparent near the source of compaction, in our case, at the
soil surface. The column experiments showed that the presence of small pores
in the upper layer of the compacted soil profile leads to higher evaporation
loss and salt precipitation rates, due to the increase of hydraulic
connectivity to the soil surface and the prolongation of the first stage of
evaporation.