Agronomic performance of sheep manure–enriched municipal solid waste compost for red beetroot cultivation (Gharb region, Morocco)

Abstract

Industrial waste poses a major challenge in Morocco and worldwide, as its increasing production presents significant environmental concerns. In Morocco, approximately 1.6 million tonnes of industrial waste are generated annually, with a considerable portion classified as hazardous, primarily from the agri-food, chemical, and construction sectors. These wastes contribute substantially to greenhouse gas emissions and the deterioration of soil and water quality, acting as a barrier to sustainable management. In this context, composting strategy emerges as a promising method for the valorization of organic waste. This study focuses on the formulation of compost derived from the industrial waste of medicinal and aromatic plants (EDEPAM company), combined with agro-industrial waste (strawberry), and supplemented with sheep manure to correct nitrogen deficiencies. After 150 days of composting followed by 30 days of maturation, the final product showed stable and favorable physicochemical characteristics [Nitrogen (1.82%), C/N ratio (15.07), pH (7.94)], while maintaining a high organic matter content. The agronomic validation was conducted in greenhouse conditions on beetroot (Beta vulgaris L.) grown in two contrasting soil types (Fluvisol and Vertisol), revealing a significant improvement in growth and photosynthetic performance at moderate application rates (25% of compost). These findings highlight the potential of integrating compost to enhance both crop yields and soil quality, thereby supporting sustainable and locally adapted agricultural practices.