Applying Risk Indices to Assess and Manage Soil Salinization and Sodification in Crop Fields within a Mediterranean Hydro-Agricultural Area

Abstract

Irrigation-induced or secondary salinization can occur when salts are introduced by irrigation water and accumulate within the root zone due to insufficient leaching. Mediterranean regions are especially susceptible, given the predominant climate and the expanding of irrigation areas. In this study, two indices to assess the risk of salinization (RSA) and sodification (RSO), previously applied at a regional scale, were used in a hydro-agricultural area (AHA) in Southern Portugal, in ten crop fields. Information on climate, irrigation water quality, soil characteristics, and land use was obtained from large databases and from local data. The results revealed the feasibility of using the RSA and RSO indices both on large and smaller scales, seeing as most of the area in the monitored crop fields presented the same risk classes (62% in RSA and 78% in RSO). Deviations were due to the reduction in scores for drainage and, in the case of RSO, the assigned irrigation method based on the land occupation class. Considering that different spatial scales of risk assessment are associated with different objectives and management options, a risk management framework was outlined following a multi-scale perspective for mitigation actions in salt-sensitive areas, ranging from territorial planning to the adoption of on-farm practices that can contribute to the sustainability of irrigated agriculture.

Growth responses and genetic variation among highly ecologically diverse spring wheat genotypes grown under seawater stress

“…Conducting research to find alternative ways to solve salinity problems is essential to meet current and future food demands. Suitable management practices to control salinity problems must be implemented in irrigated fields, irrigation projects, and geohydrologic systems (Tomaz et al, 2021). Among these practices, soil erosion control measures, rainwater harvesting, integrating appropriate plant species, and efficient irrigation methods are routine practices for obtaining suitable and sustainable results (Singh et al, 2018).…”

Water Quality Assessment of a Hydro-Agricultural Reservoir in a Mediterranean Region (Case Study—Lage Reservoir in Southern Portugal)

“…The most important potential problem is the reduction of soil infiltration rates caused by excessive Na, with a slight to moderate degree of restriction of use in almost all water samples. Low-salt water can reduce infiltration even for a low SAR; that is, the overall salinity of the applied water can be insufficient to counteract the negative effects of sodium on soil structure with the risk of soil sodification [8,18,19,53]. Considering the FAO standards, Na, B, and NO 3 concentrations would not constitute any degree of restriction of use in sprinkler irrigation, (the most commonly used method in field crops).…”

Ordenamiento territorial y planificación prospectiva en gobiernos locales: Una revisión literaria

“…Asumido para orientar el desarrollo de asentamientos por todos los países europeos. (Tomaz et al 2021).…”