Soil salinity assessment and coping strategies in the coastal agricultural landscape in Djilor district, Senegal

Abstract Soil salinity remains one of the most severe environmental problems in the coastal agricultural areas in Senegal. It reduces crop yields thereby endangering smallholder farmers’ livelihood. This paper aims to investigate soil salinity pattern and relationship with some environmental factors based on 304 soil sample plots (at 0–30 cm depth) coupled with farm household survey in Djilor district, Fatick Region. Elevation, slope, groundwater depth, and normalized difference vegetation index (NDVI) values of each sample plots were extracted using the ArcGIS. Through statistical analyses, the results showed that bare land, land under fallow, rice plots and Fluvisols (soil type) registered high content of salt. Clay content, soil pH, elevation, distance to river and Fluvisols were significant factors associated with the increased salt content. Contrary to expectations, soil salinity had no relationship with groundwater depth in the study area. Ninety-six percent of the respondents were affected by salinization. Women group engaged in rice farming appeared to be more affected by soil salinity. To cope with the negative impact of soil salinity in the study area, the farmers’ strategies are the application of chemical fertilizer and manure, planting and conservation of trees, and installation of soil bunds. Smallholder farmers also expressed their need for support on adaptation and mitigation from the government or any concerned organizations involved in this environmental issue. This study provides a baseline in soil salinity assessment and helps decision makers regarding land management and salt-affected areas restoration.

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