Effect of farming strategies on environmental impact of intensive dairy farms in Italy

Abstract

Agriculture and animal husbandry are important contributors to global emissions of greenhouse (GHG) and acidifying gases. Moreover, they contribute to water pollution and to consumption of non-renewable natural resources such as land and energy. The Life Cycle Assessment (LCA) methodology allows evaluation of the environmental impact of a process from the production of inputs to the final product and to assess simultaneously several environmental impact categories among which GHG emissions, acidification, eutrophication, land use and energy use. The main purpose of this study was to evaluate, using the LCA methodology, the environmental impact of milk production in a sample of 41 intensive Italian dairy farms and to identify, among different farming strategies, those associated with the best environmental performances. The functional unit was 1 kg Fat and Protein Corrected Milk (FPCM). Farms showed characteristics of high production intensity: FPCM, expressed as tonnes per hectare, was 30·8±15·1. Total GHG emission per kg FPCM at farm gate was 1·30±0·19 kg CO2 eq. The main contributors to climate change potential were emissions from barns and manure storage (50·1%) and emissions for production and transportation of purchased feeds (21·2%). Average emission of gases causing acidification to produce 1 kg FPCM was 19·7±3·6 g of SO2 eq. Eutrophication potential was 9·01±1·78 ${\rm PO}_{\rm 4}^{{\rm 3} -} {\rm eq}.$ per kg FPCM on average. Farms from this study needed on average 5·97±1·32 MJ per kg FPCM from non-renewable energy sources. Energy consumption was mainly due to off-farm activities (58%) associated with purchased factors. Land use was 1·51±0·25 m2 per kg FPCM. The farming strategy based on high conversion efficiency at animal level was identified as the most effective to mitigate the environmental impact per kg milk at farm gate, especially in terms of GHG production and non-renewable energy use per kg FPCM.

Multi-dimensional assessment and scoring system for dairy farms

“…About the environmental impact aspects, the values of GWP reported are similar to what was found in a previous study in the same region by Guerci et al (2013) in intensive dairy farms, while the same authors found values of acidification and eutrophication higher than those reported in this study; this result is due to the different kind of farms included in the present study: some were intensive farms, with large use of fertilisers and high stocking density (LU/ha of land), some used small amounts of fertiliser and the number of animals per hectare was limited. Land use and eutrophication resulted higher than the findings of Meul et al (2014).…”

“…The environmental sustainability of animal products is of great concern worldwide; many studies were carried out in order to calculate the environmental impact of milk production in Italy (Guerci et al 2013;Bava et al 2014;Pirlo et al 2014) and in other countries (Del Prado et al 2013;Roer et al 2013). The Life Cycle Assessment (LCA) is the most frequently used method to assess environmental sustainability throughout the estimation of different environmental impact categories.…”

Factors Affecting Global versus Local Environmental and Economic Performance of Dairying: A Case Study of Swiss Mountain Farms

“…In that sense, our work highlights (i) the synergies that exist in the promotion of farm global environmental and economic performance and (ii) the trade-offs that are present in the enhancement of farm global and local environmental performance. Our findings regarding the trade-offs between local and global environmental performance are in line with those of Guerci et al [38] and Battini et al [16], who stressed for Italian dairy farms the potential trade-offs that may exist between global and local environmental impacts.…”

Environmental Sustainability of Alpine Livestock Farms

“…The main focus of intensive systems is to ensure greater efficiency of production and a parallel reduction of environmental impacts (Guerci et al, 2013a). To meet these purposes, the concept of precision livestock farming (Auernhammer, 2001;Wang, 2001;Zhang et al, 2002) has been proposed.…”