Assessment of Groundwater Quality and Soil Salinity/Status Under Various Irrigation Systems in Arid Region of Jamshoro District

Abstract

  The agricultural lands are being affected due to groundwater (GW) quality issues. To address this worldwide problematic situation, various irrigation studies have been practiced to identify the effects on the soil conditions. The current study has been designed to assess the GW quality and soil salinity/sodicity by different irrigation techniques in the remote mountainous area of Jamshoro district at Gul Muhammad Khaskheli farm Thana Boula Khan. The experimental plot was designed under furrow, pitcher and poly ethylene bag irrigation system. These soil characteristics indicated that the drain-ability of the soil was high, with an infiltration rate of 1.60 cm/h and water holding capacity was low. Water samples were collected at each irrigation time from sowing to harvest. The soil understudy was non-saline (ECe < 4.0 dS/m) and non-sodic (pH < 8.0, SAR < 7.5 and ESP < 15.0) before crop sowing in all the three methods of irrigation at all the three sampling depths, i.e., 0-15 cm, 15-30 cm and 30-60 cm. Thus, the quality of water used for cultivation of ladyfinger/Okra crop under all irrigation methods was Class-I quality water.The investigated results shown that ECw (electrical conductivity of water) was < 1.5 dS/m, pH < 8.0, SAR (sodium adsorption ratio) < 10.0 and RSC (residual sodium carbonate) were non detective. After crop harvest changed a little bit, change was observed in the soil, i.e., under furrow and pitcher irrigation method, the ECe, SAR. and ESP (exchangeable sodium percentage) decreased in the wetted zone and increased at the wetted periphery. Under the polyethylene bag irrigation method, ECe, SAR and ESP decreased at depths 0-15 cm and 15-30 cm but these increased at lower depth, i.e., 30-60 cm after crop harvest. However, the soil remained non-saline and non-sodic.