Energy consumption and CO2 balance in horticulture: A case study in the Veneto Region, Italy

Greenhouse gas emissions have increased global warming in the last decades. International agreements have been reached in order to reduce these emissions. Some of the solutions proposed to mitigate the problem include shifts to non-fossil fuel energy sources and projects that capture atmospheric CO 2. Agriculture can offer an important opportunity to fix CO 2. In horticulture there are few studies that quantify CO2 fixed in soil, fixed in dry marketable yield and released by the vegetable production process in order to provide a balance of CO2. An experiment using compost in horticulture was carried out at the experimental farm of the University of Padua, in the Veneto Region, Italy, between 2007 and 2010. Various crops including tomato, spinach, green bean, bean, beet, savoy cabbage and onion were grown during the four-year experiment. The experimental design included five fertilization treatments for each crop. The field vegetable production information was used in order to calculate the CO2 balance and energy consumption related to each crop. The software "Bilancio Ambientale", developed by the University of Padua, was used to obtain the balance. The combination of 50% MSW compost and 50% mineral fertilizer (T50) represents a favorable option in terms of agronomic performance and for the environment. To apply high amounts of compost is not recommendable due to low yields and high energy consumption.