Nutrient content in olive leaves through sustained irrigation with treated wastewater

Abstract

Water scarcity is posing a major challenge to sustainable development. This issue will become more pressing as the global population grows, living standards rise, food habits evolve, and the effects of climate change intensify, resulting in rising temperatures globally. Reusing treated wastewater reduces effluent discharge into natural water bodies while also providing a reliable water source for applications that do not require high-quality water. A field trial was conducted on plots where olive trees grow. Two water treatment scenarios were investigated: one with a conventional water source as the control and one with treated wastewater as an alternative.Soil and irrigation water were characterized in the study regions, and chlorophyll, macro and micronutrients in olive leaves were analyzed. Soils treated to long-term wastewater irrigation had considerably higher electrical conductivity, total nitrogen, potassium, sodium, magnesium, zinc, and cation exchange capacity values than control. Notably, control soils had much greater levels of zinc and phosphorus than treated wastewater-irrigated soils. Except for phosphorous content (greater in plants from treated wastewater irrigated plots) and zinc content (lower in plants from treated wastewater irrigated plots), no significant variations in nutrients evaluated occurred for crops. In general, when comparing irrigation with reclaimed wastewater to irrigation with fresh water, no negative influence on tree performance was detected over time. Nevertheless, it's crucial to consider the potential risk of soil salinization associated with the consistent use of this water for irrigation.