Protein futures for Western Europe: potential land use and climate impacts in 2050

Abstract

Multiple production and demand side measures are needed to improve food system sustainability. This study quantified the theoretical minimum agricultural land requirements to supply Western Europe with food in 2050 from its own land base, together with GHG emissions arising. Assuming that crop yield gaps in agriculture are closed, livestock production efficiencies increased and waste at all stages reduced, a range of food consumption scenarios were modelled each based on different ‘protein futures’. The scenarios were as follows: intensive and efficient livestock production using today’s species mix; intensive efficient poultry–dairy production; intensive efficient aquaculture–dairy; artificial meat and dairy; livestock on ‘ecological leftovers’ (livestock reared only on land unsuited to cropping, agricultural residues and food waste, with consumption capped at that level of availability); and a ‘plant-based eating’ scenario. For each scenario, ‘projected diet’ and ‘healthy diet’ variants were modelled. Finally, we quantified the theoretical maximum carbon sequestration potential from afforestation of spared agricultural land. Results indicate that land use could be cut by 14–86 % and GHG emissions reduced by up to approximately 90 %. The yearly carbon storage potential arising from spared agricultural land ranged from 90 to 700 Mt CO2 in 2050. The artificial meat and plant-based scenarios achieved the greatest land use and GHG reductions and the greatest carbon sequestration potential. The ‘ecological leftover’ scenario required the least cropland as compared with the other meat-containing scenarios, but all available pasture was used, and GHG emissions were higher if meat consumption was not capped at healthy levels.

Defining a land boundary for sustainable livestock consumption

“…This approach has been examined by others too, both within and beyond the scientific community, and has been referred to as producing livestock on “ecological leftovers” (Garnett, ), “default livestock” (Fairlie, ), or as the “consistency narrative (Schader et al., )”. It has been offered as a potential strategy to reduce the environmental impact of ASF production (Röös et al., , ,; Schader et al., ; Van Zanten, Meerburg et al., ; Wirsenius et al., ). Biomass that we cannot or do not want to eat consists of biomass from grassland and leftovers.…”

“…Besides the environmental argument, this pathway also stresses that the high consumption levels of ASF, especially red processed meat, in the western world are associated with the rise in noncommunicable diet‐related diseases, such as obesity, heart diseases, and cancer (Tilman & Clark, ). Only a few recent studies focus on a third, alternative pathway and consider the role that ASF can play in feeding the world when production and therefore consumption are capped at levels that avoid food–feed competition and thus reduce the need for arable land (Elferink, Nonhebel, & Moll, ; Fairlie, ; Garnett, ; Peters et al., ; Röös, Patel, Spångberg, Carlsson, & Rydhmer, ; Röös et al., ,; Schader et al., ; Smil, ; Van Kernebeek, Oosting, Van Ittersum, Bikker, & De Boer, ; Van Zanten, Meerburg, Bikker, Herrero, & De Boer, ). Results of those studies show that by eating a small amount of ASF from livestock fed on “low‐opportunity‐cost feedstuff” (livestock fed with products that we cannot or do not want to eat directly and biomass from grasslands further referred to as “low‐cost livestock”), we can feed the global population with lowest possible use of arable land.…”

“…The pathway in which feed‐food competition is avoided (i.e., low‐cost livestock) is a relatively unexplored area. Although it has started to gain increasing attention (Elferink et al., ; Fairlie, ; Garnett, ; Garnett et al., ; Peters et al., ; Röös et al., , ,; Schader et al., ; Smil, ; Van Kernebeek et al., ; Van Zanten, Meerburg et al., ); Supporting information Appendix S2), the existing work has hitherto not been synthesized into a consistent review. The aim of our paper is to assess the potential contribution of livestock – fed with low‐opportunity cost feedstuff – to food supply, while reducing arable land use.…”

The Moral Justification Behind a Climate Tax on Beef in Denmark

“…A shift to a vegetarian or vegan diet can reduce emissions by 20-55%, while substituting monogastric meat (pork or poultry) for ruminant meat alone can reduce GHG emissions by 20-35% (Hallström et al 2015). Recently research into emissions from alternative sources of food have been carried out showing that diets without farmed meat (artificial meat, dairy, insects or plant based diets) has the potential to cut GHG emissions to less than a third of diets containing meat (Röös et al 2016;Halloran et al 2016;Tuomisto and de Mattos 2011).…”

Current global food production is sufficient to meet human nutritional needs in 2050 provided there is radical societal adaptation

“…Bajželj et al, 2014;Cassidy et al, 2013;Kummu et al, 2012), and, for example, the effects of changing diet on greenhouse gas emissions (Stehfest et al, 2009;Popp et al, 2010) or on global food supply (Wirsenius et al, 2010;Foley et al, 2011;Smil, 2000), but much less attention has been paid to the analysis of protein (Röös et al, 2017b) and micronutrient supply. Here, as well as following the flow of all humanedible and non-human-edible food calories, we track protein, vitamin A, iron and zinc, because shortages of these have been identified as the major causes of 'hidden hunger' (e.g.…”