Livestock production, particularly beef supply chain, is charged as the major contributor to green-house gas (GHG) emissions, as well as, in land degradation and deforestation. Environmental impacts per kg of edible beef, however, vary largely due to differences in beef production systems. Thus, this study aimed to compare the cradle-to-farm gate sustainability of four different Italian beef production systems, in terms of land occupation (LO, m(2)/year), global warming (GWP, kg CO2-eq), water depletion (WD, m(3)), acidification (AP, g SO2-eq) and eutrophication (EP, g NO3-eq) potentials by using the LCA methodology (SimaPro 8.01 PhD, PRe Consultants). The primary data were obtained from 25 farms: 7 farms conducting cow-calf operations, with specialized beef cattle maintained on pasture and finished in confinement, (Specialized extensive, SE); 6 farms conducting high grain fattening of specialized beef breed imported calves (Fattening systems, FS); 5 farms conducting cow-calf operations, with specialized beef animals constantly kept in confinement (Cow-calf intensive; CCI); 7 farms conducting cow-calf operations, with Podolian cattle (a native breed of Southern Italy) maintained on pasture and finished in confinement, (Podolian system; PoS). The functional unit was 1 kg of live weight of marketed beef cattle. Intensive systems (i.e. CCI and FS) showed lower GWP values than systems partially based on pasture such as PoS, and even SE (17.62 +/- 1.78 and 21.94 +/- 1.95 kg CO2-eq vs 26.30 +/- 1.65 and 25.41 +/- 1.65 kg CO2-eq, P < 0.01, for FS, CCI, SE, and PoS, respectively). No significant effect of production system on WD was observed. Acidification potential was significantly (P < 0.001) affected by production system with the highest values observed in CCI (0.30 +/- 0.02 kg SO2-eq) compared with the other three beef production systems. As for eutrophication potential, FS and PoS tended to show lower values compared with CCI and SE systems (961.71 +/- 65.30 and 779.17 +/- 70.53 g NO3-eq vs 1009.20 +/- 77.27 and 1009.71 +/- 65.30 g NO3-eq, respectively; P < 0.10). Significant differences (P < 0.001) were observed for LO between the four systems (177.71 +/- 20.87 and 194.43 +/- 20.87 m(2)/year vs 40.67 +/- 22.54 and 32.60 +/- 23.69 m(2)/year, for PoS and SE vs FS and CCI, respectively). However, as diets in intensive meat systems are mainly based on cereals products that humans could consume directly, the degree of competition with human nutrition should be another feature to be considered. About this aspect, although human edible protein conversion efficiency (HEPCE) was not significantly influenced by production system, PoS showed a higher HEPCE index (0.44 +/- 0.08), particularly if compared with CCI system (0.17 +/- 0.09), but also in comparison with groups FS and SE (0.34 +/- 0.08 and 0.39 +/- 0.08, respectively). In addition, grass-based systems may provide other non-commodity outputs and non-marketable public goods services named "ecosystem services" (e.g. provision of clean drinking water, preservation and enhancement of biodiversity, conservation of cultural landscapes, contribution to the socio-economic viability of many rural areas particularly in marginal areas, enhancement of meat quality and animal welfare as perceived by consumers).The present results showed a lower impact of the intensive beef production systems in terms of GWP and LO, whereas some of them were more impactful at AP and EP levels. However, in order to achieve a more accurate estimation of the impact of the beef production chain, particularly for traditional and extensive farming systems conducted in marginal areas, such as the Podolian system, further LCA studies are needed, taking into account the allocation of their ecosystem services. (C) 2017 Published by Elsevier Ltd.
|Titolo:||Environmental impacts of Italian beef production: A comparison between different systems|
|Data di pubblicazione:||2018|
|Appare nelle tipologie:||1.1 Articolo in rivista|