Sevenfold variation in global feeding capacity depends on diets, land use and nitrogen management

Localized nitrogen management strategies can halve fertilizer use in Chinese staple crop production

Nitrogen (N) management is the key to achieving food security and environmental sustainability. Here we analyse N flows using a localized N management model for wheat, maize and rice in 1,690 Chinese counties, with a breakdown of multiple reactive N (Nr) loss pathways. Results show that the total N input for producing these three staple crops in China was 22.2 Tg N in 2015, of which 7.4 Tg N was harvested as grain N and 4.0 Tg N was Nr losses in the forms of NH3 (47%), NOx (10%), N2O (3%), and leaching and runoff (40%). By assuming a production level equivalent to that of the top 10% of counties with the highest N use efficiency and yields surpassing the regional average, we reveal the possibility of achieving national staple crop production targets while improving net ecosystem economic benefit in 2050 through a 49% reduction (10.4 Tg N) in synthetic N fertilizer inputs and a 52% decrease (2.9 Tg N) in Nr losses.

Global food expenditure patterns diverge between low-income and high-income countries

Globalization, income growth and changing cultural trends are believed to prompt consumers in low-income countries to adopt the more affluent diet of high-income countries. This study investigates the convergence of food expenditure patterns worldwide, focusing on total food expenditure, raw food categories and ultra-processed foods and beverages across more than 90 countries over the past decades. Contrary to prior belief, we find that food expenditure patterns of lower-income countries do not universally align with those of higher-income nations. This trend is evident across most raw food categories and ultra-processed foods and beverages, as the income level of a country continues to play a crucial role in determining its food expenditure patterns. Importantly, expenditure patterns offer estimates rather than a precise idea of dietary intake, reflecting consumer choices shaped by economic constraints rather than exact dietary consumption.

Beyond the Farm to Fork Strategy: Methodology for designing a European agro-ecological future

The publication of the European Commission's Farm to Fork Strategy has sparked a heated debate between those who advocate the intensification of agriculture in the name of food security and those who recommend its de-intensification for environmental reasons. The design of quantified scenarios is a key approach to objectively evaluate the arguments of the two sides. To this end, we used the accounting methodology GRAFS (Generalized Representation of Agri-Food Systems) to describe the agri-food system of Europe divided into 127 geographical units of similar agricultural area, in terms of nitrogen (N) fluxes across cropland, grassland, livestock, and human consumption. This analysis reveals, in current European agriculture, a high level of territorial specialization, a strong dependence on long distance trade, and environmental N losses amounting to about 14 TgN/yr, i.e. nearly 70 % of the annual N input (including N synthetic fertilizers, symbiotic N fixation, oxidized N deposition and import of food and feed). Based on the analysis of the yield-fertilization relationship of cropping systems at the scale of their full rotation cycle, and on a simplified model of livestock ingestion, excretion and production, we advanced the GRAFS methodology for prospective scenario design. Three scenarios for the European agri-food system were explored for 2050: a business-as-usual (BAU) scenario, a scenario based on the measures considered by the EU Farm to Fork Strategy (F2F), and a fully agro-ecological scenario (AE). The results show that the F2F scenario reduces the dependence of Europe on imports of synthetic fertilizers and feed resources by 40 % as well as the environmental N losses by 30 %, but not to the level of its claimed ambitions as N lost to the environment still amounts to about 10 TgN/yr, i.e. 67 % of N inputs. Of the three scenarios studied, only in the AE scenario, involving the relocation of feed production, the generalization of organic crop rotations with N fixing legume crops, and a shift of agricultural production and food consumption toward less animal-based products, would Europe be able to dispense with N imports, still being able to export some cereals, meat, and milk products to the rest of the world, while halving today's reactive N emissions to the environment.