Effects of watertable depth, irrigation water salinity, and fertilizer application on root zone salt buildup

Patel, R.M., Prasher, S.D. and Bonnell, R.B. 2000. Effects of watertable depth, irrigation water salinity, and fertilizer application on root zone salt buildup. Can. Agric. Eng. 42: 111-115. Salt buildup due to irrigation water salinity and fertilizer application was studied in field Iysimeters planted with green peppers (Capsicum annuum).Waterwas applied by subirrigation, and the fertilizers were incorporated at the soil surface. Three subirrigation water salinities, I, 5, and 9 dS/m and two watertable depths, 0.4 and 0.8 m, were used. The soil salinity was determined by first measuring the bulk soil salinity by time domain reflectometry (TDR) and then converting it to soil solution salinity (ECsw)' It was found that the salinity of the subirrigation water affected ECsw in the upper soil profile when the watertable was maintained at 0.4 m depth. The subirrigation water also affected the lower half of the soil profile when the watertable was maintained at 0.8 m depth; however, it did not affect any salt buildup in the upper half. Also, the addition of N, P, and K fertilizers did not contribute to the salt buildup in the soil. Although watertable depth and subirrigation water salinity affected ECsw' they did not affect the green pepper yield. The experiment was conducted using field Iysimeters filled with a sandy soil and covered with a plastic sheet to simulate arid conditions. Therefore, caution should be exercised in extrapolating the results of this study to field conditions and other soils. L'accumulation de sel dans Ie sol due a l'irrigation avec de l'eau saline et aI'utilisation de fertilisants, a ete etudie au champs dans des Iysimetres OU ont ete semes des plants de piment vert (Capsicum annuum). Un systeme d'irrigation souterraine a ete utilize, et les fertilisants ont ete incorpores ala surface du sol. Nous avons teste trois