Effect of slaughter age on environmental efficiency on beef cattle in marginal area including soil carbon sequestration: A case of study in Italian Alpine area

The production of beef carries significant environmental repercussions on a worldwide level. Considering that the production of beef in Alpine mountainous regions, such as South Tyrol (Italy), constitutes a modest yet progressively growing segment within the local agricultural sector focus must be put on minimizing the environmental impact of producing one kilogram of meat, while also accounting for the carbon sequestered by Alpine pastures in such marginal areas. To this end 20 beef farms distributed in the South Tyrolean region (Italy) were divided based on the age at slaughter of the beef cattle: 10 farms with a slaughter age of 12 months (SA12) and 10 farms with a slaughter age of 24 months (SA24). Live cycle assessment (LCA) approach was used, and the impact was estimated using two functional units (FU): 1 kg of live weight (LW) and 1 kg of carcass weight (CW). Global warming potential (GWP₁₀₀, kg CO₂-eq), acidification potential (AP, g SO₂-eq), and eutrophication potential (EP, g PO₄-eq) were investigated. Furthermore, within the account, the carbon sequestered by pastures and permanent grassland has been included for estimated the overall carbon footprint. In terms of GWP₁₀₀, the SA12 system proved to be significantly lower for both two functional units under studies, with reductions of 8.5 % and 7.4 % in terms of LW and CW, respectively, compared to the SA24 system, specifically, the SA12 system showed an environmental impact in terms of GWP₁₀₀ of 19.5 ± 1.1 kg CO₂-eq/kg LW, which was significantly lower than the SA24 system that exhibited a value of 22.9 ± 1.1 kg CO₂-eq/kg LW (P < 0.05). When accounting for the carbon sequestered within the system, the observed values in terms of GWP₁₀₀ are significantly lower for SA12 compared to SA24, 17.6 ± 1.5 vs. 20.9 ± 1.5 kg CO₂-eq/Kg LW (P < 0.05), and 29.2 ± 2.5 vs. 38.7 ± 2.5 kg CO₂-eq/Kg CW (P < 0.01). These differences are due to less purchase of concentrated feed and greater use of natural resources such as pastures and permanent grasslands. The research indicated that the production of beef in the Alpine region of South Tyrol predominantly occurs within extensive parameters, leading to a satisfactory environmental profile, also including the C sequestration.