Assessment of Environmental Footprints in Pasture-Based Dairy Systems with Different Levels of Intensification

Abstract

Intensification of pasture-based dairy systems is a key strategy to improve productivity. However, assessing its environmental impacts is essential to understand its sustainability. The aim of this study was to evaluate a set of environmental footprints in two pasture-based dairy systems with contrasting levels of intensification. Two systems were compared: OS (Operational Simplicity), with lower stocking rate (1.8 LU/ha) and self-sufficiency, and HP (High Productivity), with higher stocking rate (3.0 LU/ha) and greater reliance on external inputs. Both systems were located in the Southern Regional Centre (FAGRO–UDELAR, Canelones, Uruguay). Multiple impact categories were estimated per kilogram of fat- and protein-corrected milk (FPCM). For the carbon footprint, IPCC Tier 2 (2019) guidelines were followed, while for the other impacts the ReCiPe assessment methodology was applied. The HP system showed lower impacts in carbon footprint (0.94 vs. 0.99 kg CO₂-eq), acidification (0.0043 vs. 0.0051 kg SO₂-eq), eutrophication (0.0019 vs. 0.0024 kg P-eq), and water scarcity (0.18 vs. 0.20 m³). This trend of greater efficiency in the AP system was consistent across all other indicators, including lower fossil fuel depletion (3.80 vs. 4.82), mineral resource depletion (7.76e-07 vs. 1.11e-06), and ozone layer depletion (5.83e-09 vs. 7.81e-09), compared to the OS system. The intensification strategy of the HP system not only resulted in higher productivity but also demonstrated greater overall environmental efficiency. These findings show that, for the cycle analysed, intensification led to a reduction in environmental impact per unit of product. However, higher productivity, although more efficient, could imply a greater absolute environmental burden.