Environmental Assessment of an Integrated Greenhouse Tomato Crop Grown Under Northern Conditions
The environmental burdens associated with fossil energy use, in addition to water and fertilization management continue to be major concerns for Northern greenhouse production systems. To reduce the environmental impacts of greenhouse farming under Northern climate conditions and to maintain its competitiveness, the use of renewable energy sources and suitable nutrient and waste management are becoming essential.
From this perspective, a closed-loop organic production system that increases the effciency of water and nutrient use on-farms and utilization of waste biomass was developed and tested in the province of Quebec, Canada. The goal of this study was to assess the environmental impacts of this integrated system compared to a conventional system in order to use its environmental profile as a starting point for improving the sustainability of existing systems. The environmental analysis was conducted with LCA methodology as defined by the ILCD handbook (2010) and the SimaPro v.7.3 software. The functional unit was 1000 kg of tomatoes.
The system boundary was from raw materials extraction to the farm gate. The life cycle stages considered were the infrastructure, auxiliary equipment, climate control system, farm operation, fertilizers, pesticides, waste management and packaging.
Results from the environmental assessment indicate that high energy demand had the major contributions to all impact categories when fossil energy is used. When biomass was used as renewable energy, biomass transport became the most important environmental impact factor. Increasing the truck capacity as well as reducing the distance from the farm to the biomass source reduced environmental burdens related to energy. Greenhouse structure made the second highest contributions to environmental impact categories. For the organic crop scenario, fertilizers and biopesticides had a negligible impact.
Results are discussed in terms of potential alternatives towards zero emission and to reach energy neutral for a Northern greenhouse production system.
Society of Environmental Toxicology and Chemistry (SETAC) North America 32nd Annual Meeting. Boston, MA, USA. November 13 to 17, 2011.