A global multi-indicator assessment of the environmental impact of livestock products

Driven by a growing and more affluent population, changing diets and lifestyles, the demand for livestock products is expected to surge in the next decades. Satisfying this demand will result in additional pressures on land systems. The increasingly globalized supply chains of the livestock economy will further decouple many of these impacts from the places where livestock are reared. In this study, we determined the impact intensities of global livestock production across three environmental indicators: deforestation, biodiversity loss and marine eutrophication. To this end, we used global data on the production of crops (and grass), their trade and use as feed in livestock-production systems, as well as livestock production data. We found the highest deforestation and biodiversity impact intensities in the tropics in Central and South America, Southeast Asia and Central Western Africa. In contrast, the highest values for marine eutrophication intensities were found in countries located in Northern Europe and in South and in East Asia. Our analyses show differences caused by varying efficiencies in livestock production systems and by the sourcing patterns of feed items. In grazing systems for the production of ruminant meat, for example, the resulting impact intensities are dominated by the consumption of grass. In intensive and industrialized production systems, the bulk of the deforestation and, to a lesser extent, biodiversity impacts are linked to imported soybean feed. Our results can help identify livestock production systems and countries that would qualify as priority action targets, as well as potential entry points to make their livestock production systems more sustainable. They can also be used to assist consumers in comparing impacts across and within livestock food product types. Ultimately, understanding the environmental impacts embodied in global supply chains of livestock products can help create better regulatory policies and science-based interventions for protecting terrestrial and marine ecosystems.