Evaluation of Different Types of Leaching Models in Two Pilots of South East Khoozestan Province

In dry area, such as IRAN, where have low precipitation and high evaporation, salt accumulation on soil surface is unavoidable. Therefore it is necessary to use an applicable method for estimation of the water requirement for agricultural soil improvement. The aim of this research was drawing desalinization and dealkalization curves and applying the best type of empirical leaching models for leaching salt and sodium of south east Khoozestan province. This research has down in two areas of Khoozestan state. For this propose, two experimental areas were selected and four treatments with three replications were designed. The treatments were included 25cm, 50cm, 75cm and 100cm water application. In addition of above treatments, in second area about mention treatments were repeated by amendment matter (sulfuric acid). Eleven empirical models were compared by using initial and final values of EC and Na. The results showed that manner model was the best models with 83 and 85 percent coefficient correlation in pilot No.1. Mean while in pilot No.2 the cubic model was the best model with 94 and 88 percent coefficient correlation. In this pilot when it used acid, the exponential growth, logistic, compound and inverse models with 88% coefficient correlation, had shown upper correlation.