Effect of summer grazing on carbon footprint of milk in Italian Alps: a sensitivity approach Matteo Guerci, Luciana Bava, Maddalena Zucali, Alberto Tamburini * , Anna Sandrucci Dipartimento di Scienze Agrarie ed Ambientali, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy article info Article history: Received 2 May 2013 Received in revised form 29 October 2013 Accepted 6 November 2013 Available online 19 November 2013 Keywords: Mountain dairy farming Summer grazing Carbon footprint Life cycle assessment Allocation Land use change abstract During the last decades, the Italian Alps were characterized by a very high rate of agricultural aban- donment that mainly affected small farms. The remaining farms, especially in the dairy cattle sector, moved towards increasing size, intensified production and abandonment of traditional summer grazing of the herds in high altitude pastures. The aim of the study was to estimate the carbon footprint (CF) of cow milk production in the Italian Alps, comparing the traditional farming system based on summer grazing in the highlands with the emerging more intensive systems. Moreover, a sensitivity analysis was performed to investigate the variations in the outcomes of different allocation methods and of different scenarios of land use change (LUC) emissions for soybean production. A group of 32 dairy farms was analyzed in a “cradle to farm gate” life cycle assessment (LCA); 9 of them transferred the whole herd including lactating cows to the high altitude pastures for three months in the summer season (Summer Grazing ¼ SG) while the remaining 23 (no Summer Grazing ¼ noSG) maintained their lactating cows in the valley barns all over the year. On average the farms had a small herd size (54 Æ 61 lactating cows) but a high stocking rate (3.7 Æ 2.0 Livestock Unit ha À1 ). The average milk production was 6206 Æ 1892 kg FPCM cow À1 year À1 with a huge difference between the two groups (7017 Æ 1445 kg FPCM cow À1 for noSG and 4132 Æ 1184 for SG). NoSG farms had also higher feed ef- ficiency than SG ones. The CF values obtained in the baseline scenario were 1.55 Æ 0.21 and 1.72 Æ 0.37 kg CO 2 -eq. kg À1 FPCM for, respectively, noSG and SG farms. Considering different allocation methods, no significant differences were observed between the car- bon footprint of the two systems. When LUC emissions were accounted for, CF increased especially in noSG farms due to the high amount of concentrate feed purchased. Traditional activity of summer grazing in high pastureland did not show any mitigation effect on the carbon footprint of milk, mainly as a consequence of low milk yield and low feed efficiency. The sensitivity analysis for different allocation methods and for different LUC emissions underlined the fact that one of LCA’s limits is that a change of key assumptions can determine a change of the overall results. In particular including the emissions related to LUC for soybean production significantly affects the final outcome, the amount of feed pur- chased by the farm becoming one of the major driver of milk CF. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction In the Italian mountain areas, particularly in the Alps, dairy production is still an important economic activity, strictly connected with the production of typical cheese varieties. In this area the traditional dairy farming is characterized by keeping milking cows and young stocks indoors in the lowland for most of the year, generally without access to pasture. During summer animals are transferred from the lowland barns to pastures in the highland (Penati et al., 2011). However, in the last decades dairy farming in Italian Alps has undergone a progressive change towards intensive production models typical of the lowland: from 1960 to 2000 the number of dairy cows in the central Italian Alps of Sondrio province decreased by 40% while the total production of milk increased by 14.5%; more intensive dairy farms with higher yields (specialized dairy cows), higher stocking rate and consequently lower feed self- sufficiency (with an increasing amount of purchased feed, espe- cially concentrates) replaced the traditional ones (Gusmeroli et al., 2006). Moreover, summer grazing of cows in high altitude pas- tures (from 600 to 2500 m a.s.l.) has been gradually abandoned (Gios and De Ros, 1991) and more intensive crop systems, based on maize, have partially replaced the traditional permanent meadows in the * Corresponding author. Tel.: þ39 (0)2 50316499; fax: þ39 (0)2 5031 16434. E-mail address: alberto.tamburini@unimi.it (A. Tamburini). Contents lists available at ScienceDirect Journal of Cleaner Production journal homepage: www.elsevier.com/locate/jclepro 0959-6526/$ e see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jclepro.2013.11.021 Journal of Cleaner Production 73 (2014) 236e244