Utilization of Brandy Industry Waste for Soil Amelioration and Plant Nutrient Enhancement

The accumulation and disposal of waste present significant environmental challenges, particularly in the wine and brandy industry, where distillery dregs, a by-product of ethanol distillation, contribute to pollution when discharged into waterways. This study explores the potential of distillery dregs as an agricultural ameliorant and fertiliser, focusing on their effects on soil quality and water conservation. Field experiments were conducted between 2017 and 2018, involving the application of 1,500 m³ of distillery dregs per hectare to semi-desert brown soils. Cultivated with alfalfa to assess the impact on plant growth, soil properties were analysed before and after the application. The results demonstrated that distillery dregs improved soil quality by reducing carbonate content and enhancing soil structure, with a 2.6% increase in sand-sized aggregates. Electrical conductivity decreased by up to 55% in certain sections, indicating a significant reduction in salinity. Nutrient levels, specifically nitrogen and phosphorus, showed marked increases of 55% and 49% on average, respectively, while humus content also rose significantly by 45%. Alfalfa yield increased by 22%, with improvements in plant height, green mass, and dry weight. Furthermore, concentrating distillery dregs reduced transportation costs, thereby enhancing the cost-effectiveness of the application. The findings suggest using the distillery dregs, particularly when concentrated, as an environmentally sustainable solution for improving soil health, mitigating pollution, and promoting sustainable agricultural practices.