What does the salt content in soils mean?

The salt content is the sum of all the negative and positive ions in the soil. Salts are chemical connections built up from ions which are not acids, bases or oxides. When soils have a too high salt concentration, the absorption of water becomes more difficult, and at certain concentrations, water actually withdrawals from the plant (plasmolysis). Plants react differently to salt concentrations. Salt-sensitive plants such as Adiantum, Azalea, Erica, Rhododendron and Primula tolerate less than 1 g salt/L substrate. Plants that are insensitive to salt such as Pelargonium, Cyclamen, Euphorbia, Hydrangea, Chrysanthemum and basil tolerate up to 2.5 g salt/L substrate; The salt content is mostly measured as conductivity (EC value) and converted with one factor.