Main characteristics of the soils at the six sampling sites at winter and summer.

Values are mean (mn) ± standard deviation (SD, where available) of two duplicate plots at each station. WC, water content (%); EC, electrical conductivity (dS/m); NO3, nitrate (mg/kg); P, phosphorus (mg/kg); K, potassium (mg/kg); Na, sodium (mg/kg); Ca, calcium (mg/kg); Mg, magnesium (mg/kg); SAR, sodium adsorption ratio; OM, organic matter (%); NH4, ammonium (mg/kg); Sat., saturation; clay, silt, sand, % of soil particles.