Environmental impacts of milk production and processing in the Eastern Alps: A “cradle-to-dairy gate” LCA approach

This study aimed to evaluate the environmental footprint and feed energy conversion ratio of Alpine dairy chains in Eastern Alps, taking into account both milk production processing phases, identify farm management features useful for targeting mitigation measures phase. A cradle-to-farm gate Life Cycle Assessment model that included herd manure management, on-farm feedstuff purchased feedstuffs materials (dairy farm), inputs outputs processing) was applied 75 farms (10 dairies). As functional units, we used 1 kg fat- protein-corrected (FPCM) m2 agricultural land, intensity land managed by alpine farms, respectively. Impact categories (CML-IA CED methods, background data from Ecoinvent database) assessed were global warming (GWP), GWP plus land-use change (GWP_LUC), acidification (AP) eutrophication (EP) potentials, cumulative demand (CED) occupation (LO). Feed (whole diet - ECR; potentially human-edible portion HeECR) computed as between gross feeds milk. Mean ECR 6.6 ± 0.5 MJ feed/MJ milk, which only 8% derived feedstuffs. For FPCM at farm, averaged 1.19 CO2-eq, GWP_LUC 1.31 AP 17.3 g SO2-eq EP 6.0 PO4-eq (coefficients variation, CV, ranged 17–21%), whereas mean 2.7 LO 2.1 m2/y (CVs: 40–46%). When included, impact values product 8 13 times greater than those obtained FPCM. Based on outcomes a principal component analysis, most related impacts ratios yield (MY, per unit ECR), stocking rate (SR, area), percentages concentrates (C, HeECR). Step-wise analysis evidenced strategies aiming decrease referred area same time improve should include MY, SR C jointly. These issues are particularly important sustainability mountain farming systems, need create virtuous link with local forage resources territory.