The environmental impacts of organic greenhouse tomato production based on the nitrogen-fixing plant (Azolla)

Abstract

Abstract Tomato is one of the most widely used vegetables in the world. In Canada, it is predominantly a greenhouse grown crop during the colder seasons. Hence it is necessary to study the environmental impacts of its production to improve the sustainability of greenhouse grown tomato. In this study, the organic tomato production in Quebec, Canada was conducted using life cycle assessment (LCA) method considering the cradle-to-packing system boundaries to assess environmental impacts. The system was modeled based on the value of fresh tomato at the rate of one tonne fresh product from the greenhouse and its vitamin C content represented as mg/100 g of tomato pulp. The parameters considered in the study were varying irrigation levels, and the amounts of Azolla based organic fertilizers considered, since Azolla is valued for its plant growth promoting capabilities. The results show that the production of one tonne of tomato packed had a negative-impact to human health (1.21 × 10−3 to 3.79 × 10−3 DALY), ecosystem (1.50 × 10−4 to 8.96 × 10−4 species.yr), and resources (1.89 × 10 to 3.35 × 10 $). Based on results, reduced irrigation led to increased adverse environmental impacts of production per tonne of packed tomato. However, the changes in the fertilization rate had less effect on environmental damage. The highest level of environmental damage was related to the lowest level of irrigation and the lowest level of fertilization, which mainly resulted from electricity consumption. Also, the highest level of irrigation and the lowest level of fertilization led to best environmental performance production per tonne of packed tomato. The results of this study emphasize that, although irrigation and fertilization have an important role in the performance of tomatoes and their environmental impacts, they did not significantly alter the amount of vitamin C.