Impact of Salinity on the Physical Soil Properties in the Groundnut Basin of Senegal: Case Study of Ndiaffate

Abstract

This study was conducted during the rainy season (september) to evaluate the impact of salinity on the soil physical properties. The area of study is composed of agricultural (ZC) and salt production (SA) area, none vegetalized (TV) and little vegetalized (TA) spots.Our methodological approach is based on a sampling of soils in different depth (0-20; 20-40, and 40-60 cm), the measurement of their physical properties (bulk density, infiltration test) and chemical caracteristics (pH, EC, exchangeable bases, etc.).Our results show that the measured values of electric conductivity (14 µS.cm-1 in ZC and 3290 µS.cm-1 in SA) indicate a gradient of salinity from the agricultural activities zone (ZC) towards the salt production zone (SA). The values of bulk density and infiltration, vary according to a gradient of salinity which goes decreasing from the none vegetalized spots (TV, (> 2.40 kg.m-3; 0 mm.h-1) to the little vegetalized spots (TA, (2.4 kg.m-3; 0.2 mm.h-1), the salt production area (SA, (2.32 kg.m-3; 2.4 mm.h-1) and finally to the zone of agricultural activities (ZC, (2.12 kg.m-3; 14 mm.h-1).This result establishes a relation between the gradient of salinity and the modification of the studied soil physical parameters. The practice of salt production involves an increase in the salinity of the soils.