Evaluation of ground water for irrigational purposes in Abu Surra area and its vicinities, se Az Zawia city, Libya

Abstract EN

Groundwater is the prime source of acceptable water for irrigation in the arid and semi-arid regions like Libya.

demand for groundwater is increasing in Libya due to population growth and significant economic advancement.

as agricultural practices are the main land use in Jifarah plain, northwest Libya, the majority of extracted groundwater from Quaternary aquifer is used to meet the increasing demand of irrigation.

in the present study, the groundwater quality for suitability in agriculture from Abu Surra area and vicinities (28.96 km2), in the central part of Jifarah plain(South Az Zawia City), has been evaluated.

a total of 21 groundwater samples have been collected from various locations of study area and analysed for pH, EC, TH, Ca2+, Mg2+, Na+, K+, HCO3-, Cl- and SO4-.

to assess the groundwater quality for irrigation purpose, parameters like electrical conductivity (EC), total dissolved solids (TDS), soluble sodium percentage (SSP), sodium adsorption ratio (SAR), residual sodium carbonate (RSC) and magnesium adsorption ratio (MAR) values have been calculated.

Chloride (Cl-) and toxic metal content are also taken in consideration.

the study reveals that 85 % of groundwater samples for EC values and 90 % for TDS values are permissible for irrigation purpose.

and SSP, SAR, RSC, MAR and chloride values show 100 % of groundwater samples suitable for irrigation purpose.

according to the USSL diagram, most of the groundwater samples fall in c3-s1 (90.48%) class indicating high salinity and low sodium water, which can be used for almost all types of soil with little danger of exchangeable sodium that the groundwater could be used for all types of crops on soils of medium to high permeability.