THE STUDY OF SATURATED HYDRAULIC CONDUCTIVITY FOR FIVE PESTICIDES IN TWO TYPES OF AGRICULTURAL SOILS

Abstract

Five pesticides were selected match, polo, topas, Diazinon and alphacypermethrine which were belonging to various groups in it chemical structure, to assess their vertical mobility in two types of agricultural soils which have been taken from the surface layer ( 0 – 30) cm in Abu-Khasib and shiabah with two different texture clay soil and sandy loam soil respectively.The results illustrated non ability of pesticides on mobile in clay soil, so they tend to remain in it, as result these pesticides lost theirs ability of movement and reaching to ground water to pollutant it .while alphacypermethrine and topas were showed the ability of movement in sandy loam soil, whereas diazinon showed least to absence of movement in that soil, as for the match was founded to be middle in its movement, on the contrary of polo which its movement was least.The studied pesticides demonstrated differents in humidity proportions for the soil with clay texture Also values of Hydraulic conductivity which was considered the most variable characteristic in the soil , since its depending on the property of liquid and soil together. Where the ratio of humidity varied for clay soil by passing the different pesticides through it with high significant level at (0.01) for humidity as well porosity (f) and Hydraulic conductivity and the difference were significant at level (0.05) for Bulk density (ρb) too.The results demonstrated, their was a positive direct relationship between Hydraulic conductivity and volumetric humidity (pv) by (0.44) degree as well as this study showed the stability of Hydraulic conductivity values after leaching the soil from pesticides with normally water.Two studies have been carried out to measure the standard Hy.Co.of two types of soils clay and sandy loam . First, the pesticides were passed through a column of soil and their Hy.Co. was measured .Second, the soil was dried and the pesticides were passed through it. Then the soil was washed by water for measuring the Hy.Co.