Salt in groundwater system

There are three main sources of salts, irrigation water, fertilizer, and naturally occurring salts in the soil that may be dissolved under irrigation. We can assume that the salts precipitating out of solution balance the amount of salts dissolving from the soil. Salts from fertilizer are also neglected in this study. Salinity measurements data were obtained monthly from 1999 to 2002 in every groundwater observation well, canal and drainage, and used to quantify the salt budget together with irrigation and drainage volume data. Salt movement with groundwater movement is simulated using the follow equation:

SM = TDS ^. WM (5)

where, SM[TON/T] is salt mass flux in groundwater, TDS is observed total dissolved solids, and WM[TON/T] is groundwater mass flux.