Impact of deep flow cultivation systems on sustainability of field vegetable production

In 2009, a research program was initiated in the Netherlands to develop soilless cultivation systems for outdoor crops, with the objective to design cost effective cultivation systems with minimal emissions of fertilizers and pesticides. To test whether these objectives have been achieved, a sustainability impact assessment of growing vegetable crops on a deep flow system was performed. We developed a conceptual framework consisting of a set of quantitative and qualitative environ-mental, economic and social indicators. Application of the framework showed that compared to field cultivation, deep flow cultivation performs better on land use, pesticide use, nutrient use and water use. However, profitability decreases, and green-house gas emission and direct energy use increase considerably. Sustainability gains and losses vary between crops. Uncertainties and opportunities were revealed, thereby directing further optimization of the deep flow system in crops where its performance is promising. Moreover, transparency about the system’s sustainability is crucial for the systems’ social and political acceptance and for its adoption by farmers.