Reshaping the European agro-food system and closing its nitrogen cycle: The potential of combining dietary change, agroecology, and circularity

Abstract

After World War II, the evolution of Europe's agro-food system has been marked by intensified use of synthetic fertilizers, territorial specialization, and integration in global food and feed markets. This evolution led to increased nitrogen (N) losses to aquatic environments and the atmosphere, which, despite increasing environmental regulations, continues to harm ecosystems and human well-being. Here, we explore how these N losses can be drastically reduced in a scenario synergistically operating three levers: (1) a dietary change toward less animal products and an efficient recycling of human excreta; (2) the generalization of region-specific organic crop rotation systems involving N 2 -fixing legumes, making it possible to do without synthetic N fertilizers; and (3) the reconnection of livestock with cropping systems allowing optimal use of manure. This scenario demonstrates the possibility to feed the projected European population in 2050 without imports of feed and with half the current level of environmental N losses.

Forest Transitions in the United States, France and Austria: dynamics of forest change and their socio- metabolic drivers

“…Secondly, minimizing agricultural land demand and mitigating emissions, while providing healthy food for all will be a major future sustainability challenge. Here, combining low-meat diets with agroecological intensification (Billen et al, 2021 ; Morais et al, 2021 ; Theurl et al, 2020 ), including the integration of trees in agricultural systems (Ramachandran Nair et al, 2009 ), appear as promising options. In addition, support for context-specific sustainable land-use practices that preserve forest ecosystems or increase forest cover while meeting local needs has been demonstrated to be not only more just, but also more effective, if collaboration with local communities (Min-Venditti et al, 2017 ) and specifically with Indigenous Peoples (Sze et al, 2021 ) is realized.…”

The compatibility of circularity and national dietary recommendations for animal products in five European countries: a modelling analysis on nutritional feasibility, climate impact, and land use

“…8 Although the necessity to reduce the consumption and production of animal products is generally acknowledged, different solutions exist regarding how animal products could be more sustainably produced, and which animal products should be reduced and to what extent. 9,10 From a supply perspective, studies suggest that animal production systems should be intensified, which would result in lower environmental impacts per quantity of animal products produced but would require higher concentrate feed inputs given that growth could be faster. 11 From a demand perspective, studies often recommend reducing consumption of animal products substantially or to a minimum.…”

Projecting future nitrogen inputs: are we making the right assumptions?

“…Even though several recent studies implemented the dynamic yield response to N inputs in national or global scale analyses and N inputs projection (e.g. Lassaletta et al [1,23]; Mogollon et al [18]; Mueller et al [27]; Billen et al [28][29][30]), most use aggregated N inputs or NUE of all crop classes and ignore the large variability in N inputs and NUE among crops and the impacts of changing crop mixes due to dietary shifts. At the global scale, NUE in 2010 varied from 0.14 to 0.80 among 11 major crop classes [31].…”