Sustainable vineyard management: Assessing the environmental impact of vermicompost compared over mineral fertilizers

The use of mineral fertilizers in agriculture has been identified as a significant source of pollution, contributing to the formation of hypoxic water bodies and the emergence of a pressing public health concern in numerous developing countries due to nitrate contamination of drinking water. In response to the increasing recognition of the need for more sustainable fertilization methods, this study investigates the potential for vermicompost to outperform mineral fertilizers in terms of environmental performance in Galician vineyards (Northwest Spain) using the Life Cycle Assessment methodology. The analysis followed a cradle-to-gate approach, conducting a comparison between vermicompost and synthetic fertilizers across fourteen impact categories, including biodiversity loss and novel ecosystem services indicators (e.g., water purification, soil erosion prevention, and carbon sequestration). The results indicated that the use of vermicompost resulted in greater environmental impacts compared to conventional grape production (up to 17 times higher), irrespective of the functional unit, due to the elevated levels of nutrients applied and the considerable influence of vermicompost production on specific impact categories, including water scarcity, terrestrial acidification, and global warming. On the other hand, the use of vermicompost markedly improved carbon sequestration compared to conventional cultivation, with values ranging from -25.75 to -88.73 t C·ha^-1 in vermicompost scenarios, as opposed to 26.49 t C·ha^-1 in conventional scenarios, effectively offsetting their carbon footprint. In terms of soil erosion control, a decline was observed (73.45 t soil·ha^-1), irrespective of the fertilization strategy employed. The most impactful activities identified were disease control and fertilization, primarily due to on-field emissions and the production of phytosanitary products. In contrast, field operations and infrastructure had minimal influence on the overall environmental profile.