This research was conducted in Tuban Delta of Lahj province to characterize its soils’ physical and chemical properties, and identify main soil affected by salinity/sodicity, using remote sensing, GIS techniques, field verifications and a questionnaire. Most studied soils were found moderately to nearly high in alkaline-reaction with pH values of 7.3-8.9, with electric conductivity (EC) values of 1.0-13.0 mS/m, low organic matter content in top- soils (less than 1%), and very low total nitrogen (0.03-0.04%), which do not meet crop growing requirements. Available phosphorus levels for most soil are low (less than 10 ppm in top-soils), and calcium carbonate levels are moderate to high (9-18% CaCO3). Wells’ water- samples are moderately to highly saline (upto 1.70 mS/m), and sodium adsorption ratio (SAR) ranged from 6.0-21 meq/l. It indicated that non-agricultural land (like sand dune and settlement) covers 1047 ha or 23%, and agricultural land occupies 3469 ha or 77% of total land area. Soil salinity/sodicity map of study area (produced at 1:25000 scale), identified four main mapping units on basis of their salinity/sodicity degree: Normal, Saline, Saline-sodic and Sodic. Normal unit comprised 56.2%, saline land constitutes 20.9%, saline-sodic land covers 5.9% and sodic land represents 17% of the agricultural land. The Study outlined suitable practical recommendations and defined necessary interventions of land management practices for sustainable use and management of land and water resources.
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