Mediterranean soil fertility management for economically feasible and environmentally sustainable production of organic tomatoes

Mediterranean soils are naturally characterized by low organic matter. Soil organic matter is an indicator of soil health, and it directly affects soil physical, chemical and biological fertility. Preserving soil health also represents one of the main objectives of organic farming. However, each organic fertility management strategy has different effects on soil properties and specific mechanisms of action. Therefore, the aim of this research was to evaluate the effects of different fertility managements on physical, chemical, biological and biochemical indicators of soil health and to identify their potential economic impacts. Despite the low doses, treatments containing humates presented the highest yield, approximately 55 Mg ha-1, and increased soil organic carbon content of at least 1 g kg-1. These results indicate a potential environmental sustainability of the two humate products in comparison with compost and fertilizers admitted in organic agriculture.