نگرشي مجدد در مورد تاثير شوري بر تبخير

Effect of salinity on evaporation-revisited

Knowledge of salinity-evaporation relation may be of prime importance in numerous situations, e.g. water balance in reseervoirs and lakes, and designing evaporation ponds. Invoking such a relationship is the aim of the present paper. Seven treatments of drinking water (as control) and saline water with salinities of 41, 68, 81, 203, 407, and 610 dS/m were designed in Pardis of Ferdowsi University of Mashhad. Evaporation was measured from containers with a surface area of 650 cm2 during one month period (Apr. 21 to May 18, 2006). There was a climatology station just near the study area. A linear regression was stablished between measured values of evaporations and salinity levels. On the average, evaporation decreases as salinity increases. However the coefficieny of vationss (0.29-0.33) were not correlated with salinity level. Measured evaporations were compared with those of Dalton and Penman equations. There was a better fit for Penman equation, as its GSDER is closer to one (1.5-3.9) and its ME is low (0.1-1.2) as is compared with Dalton equation (higher GSDER and ME).