‘Ecologically intensive’ soil management decreases erosion and irrigation requirements while increasing soil carbon, water use efficiency and economic returns on small vegetable farms in south Uruguay

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‘Ecologically intensive’ soil management decreases erosion and irrigation requirements while increasing soil carbon, water use efficiency and economic returns on small vegetable farms in south Uruguay

Vegetable family farms in south Uruguay are caught in a spiral of unsustainability, with poor soil quality as a major cause. This thesis investigated alternative soil management strategies based on enhancing ecological soil functioning, especially through organic matter management. On-farm monitoring of soil carbon showed increases of on average 3.4 Mg.ha-1 within 5 year. Experiments with reduced tillage and mulching showed potential increases in soil water capture by up to 20% and reduction of erosion below the tolerance level. Modelling at field and farm level showed that these environmental improvements can be combined with better economic performance by saving 775 m3 ha-1 yr-1 irrigation water on average, enabling increasing the cash crop area. The win-win results of this study provide a solid basis for testing the new soil management strategies on pilot farms, using a co-innovation approach in which scientific insights are combined with farmers’ knowledge of their farms.