Soil salinization under irrigated farming: A threat to sustainable food security and environment in semi-arid tropics

Abstract

Soil salinization is a major challenge of irrigated agriculture with substantial impact on the sustainability of crop and food security. World-widely, salinization has been a major bottleneck to the expansion and advancement of irrigated farming, resulting in a significant environmental degradation, lower yields and food insecurity. The problem of soil salinity varies across the regions and it has more extensive implications in arid and semi-arid regions where the rate of evaporation is higher than precipitation. To minimize the problem, it is necessary to adopt effective management practices that reduce salinization process in irrigated agriculture. However, the effective management options need a thorough understanding of the problem itself, the way it occurs, and their contributory effects to various aspects of development. This review therefore, presents an ample description on soil salinization as a threat to the sustainability of crop production and food security in the semi-arid tropics. The review focuses on the causes, extent and distribution of salt affected soils under irrigated agriculture, influence of irrigation water on soil salinization, the effects of salinization on plant growth, crop production and soil productivity. Furthermore, the review highlights the impact of salinization on food security and social economic aspects. It also proposes management options that should be adopted to either minimize or remedy soil salinity to the desired level and increase soil quality in semi-arid areas.