Agricultural Valorization of Olive Mill Wastewater in Arid Regions of Tunisia: Short-Term Impact on Soil Biochemical Properties and Faba Bean Growth

Abstract

Olive mill wastewater (OMW) is generated seasonally a large amount during the olive oil production in southern Tunisia and it is often discharged in the open environment. OMW has a high amount of phototoxic compounds, high salinity and acidity and therefore is challenging when disposed on soil. However, in southern Tunisia, the condition climatic is arid and semis-arid region. The soil sandy is in degradation and erosion processes. New strategies have been developed to reduce these impacts in soil and to valorize a waste product as olive mill wastewater (OMW) loaded with minerals and organic matters as fertilizer in agronomy. The major aim of this study was to investigate the effects of OMW spraying onto on soil biochemical properties and Faba bean crop productivity was investigated. The result showed that the irrigation of sandy soils by different OMW doses strongly influenced their chemical and microbiological characteristics. Indeed, spreading amounts from 15 m 3 /ha to 45 m 3 /ha for three consecutive years induced a considerable improvement of soil fertility. The pH and soil phosphorus content remain stable during the three years of study, while the soil salinity was increased for the 45 m 3 /ha treatment where it exceeded to 6 dS/m. In conclusions, the dose 15 m 3 /ha is suitable for the vegetative development of the Faba bean tested plant according to the soil characteristics evolution.

Stability Analysis of Reference Genes for qPCR Studies in <i>Chenopodium quinoa</i> Ecotypes on Salt-Affected Soils

“…Olive mill wastewater (OMW) is directly dumped on agricultural soils. Annually, the volume of this liquid waste reached 30 million cubic meters in Mediterranean countries [5]. The huge quantities and the uncontrolled disposal of olive mill wastewaters (OMW) cause serious social, economic and environmental problems in the Mediterranean basin, where olive cultivation is concentrated.…”