Carrying capacity of U.S. agricultural land: Ten diet scenarios

Abstract

Strategies for environmental sustainability and global food security must account for dietary change. Using a biophysical simulation model we calculated human carrying capacity under ten diet scenarios. The scenarios included two reference diets based on actual consumption and eight "Healthy Diet" scenarios that complied with nutritional recommendations but varied in the level of meat content. We considered the U.S. agricultural land base and accounted for losses, processing conversions, livestock feed needs, suitability of land for crops or grazing, and land productivity. Annual per capita land requirements ranged from 0.13 to 1.08 ha person -1 year -1 across the ten diet scenarios. Carrying capacity varied from 402 to 807 million persons; 1.3 to 2.6 times the 2010 U.S. population. Carrying capacity was generally higher for scenarios with less meat and highest for the lacto-vegetarian diet. However, the carrying capacity of the vegan diet was lower than two of the healthy omnivore diet scenarios. Sensitivity analysis showed that carrying capacity estimates were highly influenced by starting assumptions about the proportion of cropland available for cultivated cropping. Population level dietary change can contribute substantially to meeting future food needs, though ongoing agricultural research and sustainable management practices are still needed to assure sufficient production levels.

Mapping the Lisbon Potential Foodshed in Ribatejo e Oeste: A Suitability and Yield Model for Assessing the Potential for Localized Food Production

“…Recent studies, that account for the number of persons fed per unit land area or "carrying capacity", with reference to different diets, have considered that meat-based diets are more efficient for they utilize land use for grazing and feed crops that are less suitable to other crops [42]. In fact, as was the case in the foodshed landscape plans for the plant-based and strict vegetarian diets, the results presented suggest that these areas are not necessary for food production ( Figure 11).…”

“…These data, concerning the land footprint of animal production and diets whose main protein source was animal, confirmed the results obtained in other studies. This is the case for both studies that investigated complete diets [40][41][42] and those that analyzed only the major protein-rich products [24,90,91]. For the plant-based scenario (PB), the reduction of land area on the potential regional foodshed, in comparison with the meat-based diet (MB2) was 95,032 ha (20% of MB2), and for the strict vegetarian scenario (VEG) was about 186,622 ha (40% of MB2).…”

Using a Market Basket to Explore Regional Food Systems

“…Another team member calculated the annual, per-capita cropland footprint of six of the foods, using the same structure as the U.S. Foodprint model (Peters, Picardy, Darrouzet-Nardi, Wilkins, Griffin, & Fick, 2016). Through three sets of calculations, the model estimates the agricultural land area required per capita to grow the foods in a complete diet and, correspondingly, the carrying capacity of the land base of the conterminous U.S.…”

Baselines, Trajectories, and Scenarios: Exploring Agricultural Production in the Northeast U.S.

“…These models are available for only a small set of crops; we used CSM for maize, potato, and wheat (as representative of warm-season grain, cool-season grain, and vegetable crops, respectively); and 7. Quantify the carrying capacity of the Northeast region under different diet scenarios, using the Foodprint model of Peters et al (2007) and Peters et al (2016).…”

“…This last study from the Production Team focuses on the capacity of the regional land base to produce complete diets. This was accomplished by modifying the well-documented model from Peters et al (2007) and Peters et al (2016) to make it specific to the Northeast region. This spreadsheet-based model uses data on crop yield and animal productivity to estimate the land requirement of specific diets; availability of different foods is estimated using the Loss Adjusted Food Availability dataset from USDA-ERS.…”