Green House Gases(GHG) emissions from the ornamental plant nursery industry: A Life Cycle Assessment (LCA) approach in a nursery district in central Italy

The ornamental plant nursery industry is the most important economic resource of Pistoia, a city situated in Tuscany in the center-north of Italy. The production of plants offers many benefits in the social and environmental spheres: it generates employment, improves the landscape and gives a contribution to carbon dioxide accumulation. On the other hand, nurseries are considered intensive agricultural systems, responsible for soil erosion, waste production, and soil, air and water pollution. The research presented in this paper aimed to quantify the environmental impact, in terms of GHG (Green House Gases) emissions of different nursery typologies (in-pot and in-field grown plants) and productions (small, medium and large size plants). For this reason, a LCA (Life Cycle Assessment) approach was carried out in seven different nurseries on eleven production lines. GWP (Global Warming Potential) was the impact category chosen for this analysis, and the square meter was used as functional unit to represent the differences between nursery and plant typologies, although data for "product" unit are shown as well. Results show that in-pot systems, with an emissions range of 7.444-26.489 kg of CO2-e are much more impacting than in-field grown production processes (0.607-1.013 kg of CO2-e). Such great differences are mainly due to the peat used in substrate mixes and the plastic used for pots, indeed these are the most important sources of GHG emissions, and are widely used in in-pot production, while they are not present in infield processes. The final part of the paper is devoted to a comparison of results obtained in Pistoia and other research conducted in the U.S. in order to evaluate the differences in total CO2 emissions between different plant production processes and to offer some recommendations about how to reduce GHG emissions in ornamental plant nurseries.