Water quality and its affect soils by salts in the Paraguaná peninsula, Venezuela

Abstract

A research was done to assess the relationship between the affectation of soils by salts and soil use, sample depth, saturated pasta percentage (H), and irrigation water quality. Samples of water and soil were collected from twelve farms in the Paraguaná Peninsula, north of Falcón state, Venezuela. Soil samples were taken under three soil use conditions: under native vegetation (VN), under cultiva- tion (C) and fallow (D). Each of those samples were taken at three different depths: 0-20, 20-40 and 40-60 cm. Using data from the soil electrical conductivity of a saturation extract at 25 °C (ECe) the effects of soil use and sample depth were analyzed by placing in a table of double entrance the number of samples with ECe ≥ 2 dS m-1 in each combination of these categorical variables, finding that soils under cultivation (C) had the highest number of samples with ECe ≥ 2 dS m m^-1. The effect of the saturation percentage (H) was evaluated through a correlation between H and the ECe, obtaining a low correlation (r=0.426 P= 0.0000). Ayers and Westcot (1985) and Villafañe (2011) procedures for assessing the effect of salts of irrigation water on soils (irrigation water quality) were used. Results indicated strong restrictions that may limit irrigation water utilization due to the effect of NaCl of irrigation water on soil. Nevertheless, the sampled soils showed lower values of the ECe and sodium adsorption ratio which may be due to the sandy texture in most of sampled soils