Assessment and mapping of the agro-ecological risk in the Mina plain (northwestern Algeria): Soil salinity and irrigation water quality

Abstract

The objective of this study is to contribute in assessing and mapping of the salinity risks level of soil and groundwater for irrigation in the Mina plain. The experimentation was carried out on a surface area of 4000 ha. Electromagnetic conductivity (EM) measurements and soil and well water samples were taken and analysed. The results showed an important spatial variability of the electrical conductivity (EC) of saturated paste extracts (ECe), which varied between 1.35 and 28.8 dS/m. The isovalues map of ECe was estimated by the regression equation and interpolated by the ordinary kriging (OK) method which showed that the area of saline soils (ECe > 4 dS/m) represented 90% of the study area. The results also showed poor to unsuitable well water quality. To find the risk of salinity and sodium, the water points were classified as C3S3 (2.5%), C4S2 (5%), C4S3 (30%) and C4S4 (62.5%). Spatial distribution maps of total dissolved solids (TDS), electrical conductivity of water (ECw) and sodium adsorption ratio (SAR) interpolated by inverse distance weighting (IDW) showed too high risk levels of ECw (>5000 μS/cm) and TDS (>3000 mg/l) occupying a large wellfield (70%); with regard to SAR (>18), 36% of the groundwater had a high risk of sodium. These results showed that the choice of tolerant crops, redevelopment of drainage systems and irrigation with less saline water should be designed for the sustainability of soil productivity and agro-ecosystems.

Diagnosis of Soil Salinity in the Low-Chellif Plain, North-West Algeria, By Joint Measurements Of Electrical And Hydraulic Conductivities

“…This extreme variability in the surface horizon has been consistently reported in literature (Vauclin, 1982;Coquet et al, 2000;Dewitte et al, 2012;Allbed et al, 2014;Wang et al, 2017). In-field investigations have examined spatial distributions of measured indicators such as saturated hydraulic conductivity, soil moisture, texture, and bulk density, revealing that coefficients of variation for soil water indicators often exceed those of physical indicators such as texture and bulk density (Carsel & Parrish, 1988;INSID, 2008;Berkane et al, 2021). In the surface horizon, 93% of the area is non-saline (85%) to slightly saline (8%).…”

“…Soil water permeability and salinity level mapping was conducted by employing the ordinary kriging (OK) spatial interpolation method using ArcGIS10.3. This method entails interpolating the data of different soil parameters including: salinity status, particle size distribution, and hydraulic conductivity (Walter, 1990;Burrough & Donnell, 1998;Bradai, 2017;Berkane et al, 2021).…”

Plasmatic Ionogram Profile of Ouled Djellal Ewes According to Water and Straw Salinity at Setif Highlands, Algeria

“…In Algeria, agricultural soils are mostly affected by salinity or are likely to be (Durand 1983). According to Berkane et al, (2021); 3.2 million ha are affected to varying degrees of severity. The most common salts in arid and semi-arid regions are mainly chlorides, sodium sulfates, magnesium sulfates, and to a lesser degree, sodium carbonates (Halitim, 1988).…”