Measuring environmental sustainability of poultry rearing intensive system: comparison of different approaches

Sustainability of human activities is one of the most important concerns of the European Union. Consequently, the need to assess the level of sustainability achieved both at local and at government level is increasing. This process involves all economic sectors, including agriculture and, in particular, livestock. Until several years ago livestock production systems were mainly focused on production efficiency and qualitative characteristics of meat. However, nowadays rules regarding animal welfare and environmental impact are becoming more and more compulsory and require attention by all the poultry chain. European subsidies are in many cases linked to an environmentally sound behaviour of farms. However, there is still an ongoing discussion regarding the definition of sustainable-agriculture strategic objectives, the criteria to take into account, the actions to develop, and the methodological tools to use for the evaluation. This chapter provides suggestions for improving the environmental evaluation part of a process of sustainability assessment specific for intensive poultry production. The environmental sustainability of an intensive poultry-rearing system is evaluated through the use of three different methods: Emergy Evaluation, Ecological Footprint Analysis and Life Cycle Assessment (LCA). For each of the three methods a review of its application in agriculture, and specifically in poultry breeding, is presented. Through Emergy Evaluation we found that diet is the most important impact factor for the analysed system, accounting for more than 82% of the total emergy flow. Our results obtained from Ecological Footprint Analysis point out that cropland, which is connected with chicken diet, is the main land component in the indicator, accounting for 73% of the total. Particularly, the high quantity of maize and soya needed for feed requires much cropland. Finally, using LCA, we found that feed production is the element which contributes the most to the environmental impacts of the system, influencing the impact category 'land use'. As Ecological Footprint, LCA regards the cultivation and the transformation of maize and soya as the processes with the strongest impact. Therefore, although the three methods use specific indicators and methodology, they come to the same conclusions for the system investigated. After applying each method to the poultry system, we propose a comparative analysis between the three methods, based on four different criteria: representativeness, verifiability, reproducibility, comprehensibility. By comparing the methods according to these criteria, we found that each of them shows both positive and negative aspects, strengths and weaknesses, but all of them are effective in representing the environmental features of a given activity, and the results can be used as input in the sustainability assessment process. The choice to use Emergy Evaluation, Ecological Footprint Analysis, or LCA can depend upon the main objective of the assessment process. However, in many cases it is not necessary a choice because the three methods can be used together, and the results can be integrated to build combined indicators, capable to ensure a wide and complete analysis.