ENVIRONMENTAL AND ECONOMIC PERFORMANCE OF CEREAL STRAW END-PRACTICES Nadia Palmieri 1 , Maria Bonaventura Forleo 1 , Giacomo Giannoccaro 2 , Alessandro Suardi 3 , Luigi Pari 3 *Corresponding author: Luigi Pari, luigi.pari@crea.gov.it 1 Nadia Palmieri, University of Molise, Department of Economics, nadia.palmieri@unimol.it. Phone: +39 0874404452. 1 Maria Bonaventura Forleo, University of Molise, Department of Economics, forleo@unimol.it. Phone: +39 0874404454. 2 Giacomo Giannoccaro, University of Bari "Aldo Moro", Department of Agricultural and Environmental Science, giacomo.giannoccaro@uniba.it. Phone: +39 080 544 28 85 3 Alessandro Suardi, Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria, Unità di ricerca per l’ingegneria agraria - Monterotondo (Rome-Italy) – alessandro.suardi@crea.gov.it. Phone: +39 0690675248. 3 Luigi Pari*, Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria, Unità di ricerca per l’ingegneria agraria - Monterotondo (Rome-Italy) – luigi.pari@crea.gov.it. Phone: +39 0690675249. ABSTRACT: Paper aims to identify the sustainability of cereal straw end-practices by considering environmental and economic performances at farm level. The carbon footprint and the eco-efficiency ratio of straw end-practices are estimated. Straw incorporation in the soil and baling were the two end-practices considered based on a direct survey to cereal farms located in Apulia Region, Southern Italy. The environmental impact of alternative straw end-practices was assessed by means of an ALCA and based on GHG emissions. A sensitivity analysis tested for different wheat and straw allocation methods. Results showed that incorporation into the soil was more impactful than straw baling due to straw decomposition impacts; furthermore, regardless of the practices, impacts according to the economic allocation method were lower than impacts assessed with the mass allocation method. In order to combine the environmental and economic assessment, the eco-efficiency ratio was calculated by the gross value added per 1 Mg of total wheat residue produced. Eco-efficiency results showed that straw baled for sale had the best eco-efficiency ratio per unit of GHG emitted to the atmosphere. A joint evaluation of economic and environmental performances of cereal straw end- practices through a single indicator, the eco-efficiency ratio, is the main feature of the work that adds relevance to study findings. Keywords: wheat straw; eco-efficiency ratio; farmer's behaviour; attributional life cycle assessment ALCA. 1 INTRODUCTION AND OBJECTIVE Cereal straw, a by-product of agricultural crops, is considered a potentially large source of energy supply; however, its use for bioenergy purposes [1,2,3] is still scarce. In general, on-farm cereal straw can be used for animal bedding and feeding, it can be sold, and/or it can be chopped and incorporated into the soil as fertilizer. Despite a vast literature [4], a comparison among the environmental impacts of different straw end-practices is hardly ever possible without any consideration on the types of cereal and straw, on the pedoclimatic conditions and on the agronomic techniques applied. Moreover, agricultural practices are strongly site-specific. Hence, the environmental impacts deriving from crop cultivation and from straw residues management practices are largely dependent on multiple and contextualized factors. In this paper, the environmental and economic performances of two wheat straw end-practices were analysed in order to find which practices is more efficient under both points of view. Two wheat straw end-practices are considered, namely the on-farm straw baling against the on-farm incorporation into the soil as fertilizer. The environmental performance of two wheat straw end- practices was assessed by calculating the carbon footprint of wheat and straw production. The economic performance was assessed by calculating the Gross Value Added (GVA) for each wheat straw end-practice. In order to combine the environmental and economic assessment, the eco-efficiency ratio was applied to answer the question of how much net value is added per kg of GHG emitted to the atmosphere. 2 MATERIALS 2.1. Study area The study area is located in the Province of Foggia, within Apulia Region in Southern Italy. Foggia Province has an agricultural area of about 322 thousand ha [5], and an arable land that accounts for 71% of total farmland. Winter cereals, mainly durum wheat (95% of cereals crop area), is prevailing. The Province produces one-third of Italy’s annual durum wheat output, on a total area of almost 200,000 ha [5]. In the study area, straw quantity is not recorded in the official statistics. Therefore, the amount of straw disposed of according to each end-practice is missing. The data source for this analysis was a survey of farmers. 2.2 Farm sample and survey A sample of 203 farms across 24 municipalities was obtained by surveying cereal growers in 2014. A comprehensive description of sampling and surveying is reported in [9]. The farmers who applied the two on-farm straw end-practices (i.e. straw sold baled, straw incorporated into the soil) are 127 out of 200 respondents. They operated on 2,605 ha with on average 20.5 ha of farmland size. The total cereal area sampled was 1,845. Table I reports the average yields of cereal grain and straw as stated by farmers. The two-sample t-test (with different variance) for checking differences in the mean of two groups was significant (t= -4.4543; df=125; p=0.000). The sample data showed that the yields mean for those who incorporate the straw into the soil were significantly higher. 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden 1727