Meeting Future Food Demand With Current Agricultural Resources

Abstract

Meeting the food needs of the growing and increasingly affluent human population with the planet’s limited resources is a major challenge of our time. Seen as the preferred approach to global food security issues, ‘sustainable intensification’ is the enhancement of crop yields while minimizing environmental impacts and preserving the ability of future generations to use the land. It is still unclear to what extent sustainable intensification would allow humanity to meet its demand for food commodities. Here we use the footprints for water, nitrogen, carbon and land to quantitatively evaluate resource demands and greenhouse gas (GHG) emissions of future agriculture and investigate whether an increase in these environmental burdens of food production can be avoided under a variety of dietary scenarios. We calculate average footprints of the current diet and find that animal products account for 43-87% of an individual’s environmental burden compared to 18% of caloric intake and 39% of protein intake. Interestingly, we find that projected improvements in production efficiency would be insufficient to meet future food demand without also increasing the total environmental burden of food production. Transitioning to less impactful diets would in many cases allow production efficiency to keep pace with growth in human demand while minimizing the food system’s environmental burden. This study provides a useful approach for evaluating the attainability of sustainable targets and for better integrating food security and environmental impacts. © 2016 Elsevier Ltd. All rights reserved.

Generated Summary

This research, published in Global Environmental Change, investigates the challenge of meeting future food demands while considering the planet’s limited resources. The study employs a quantitative approach to evaluate the resource demands and greenhouse gas (GHG) emissions associated with future agriculture, assessing whether increasing environmental burdens can be avoided under various dietary scenarios. The authors analyze the footprints for water, nitrogen, carbon, and land, focusing on the environmental impacts of food production. The core methodology involves calculating the environmental burdens (water, nitrogen, carbon, and land) associated with current diets and projecting these burdens under different dietary scenarios (GDP-based, Mediterranean, pescetarian, and vegetarian). By examining changes relative to the year 2009, the study determines the necessary improvements in footprint intensity to prevent an overall increase in environmental burden. It also compares the required changes to projections of historical improvements in production efficiencies. The research aims to provide a multi-metric assessment of how changes in efficiency and dietary patterns can collectively increase food supply and minimize environmental impacts from agriculture.

Key Findings & Statistics

• The study estimates that 776 m³ H2O, 15.3 kg N, 299 kg CO2eq, and 0.85 ha are required annually to support an average global diet.
• Animal products account for a significant portion of these requirements: 43% of water use, 58% of nitrogen use, 74% of GHG emissions, and 87% of land use.
• Animal products provide only 18% of an individual’s caloric intake and 39% of protein intake.
• The current diet shows considerable variation in footprint intensity across different food commodities.
• For land use, changes in beef consumption have the most significant impact, leading to a large increase under a GDP-based future and substantial reductions in other diet scenarios.
• The GDP-based diet is projected to require increases in all four environmental burdens compared to the current diet.
• The Mediterranean diet shows apparent trade-offs, with increases in nitrogen and water demand but decreases in land and GHG requirements per capita.
• Pescetarian and vegetarian diets lead to consistent and marked decreases in environmental burdens.
• Average footprint intensities will need to improve substantially (H₂O: 65%, N: 85%, GHG: 72%, Land: 97%) to prevent further increases in environmental burdens.

Other Important Findings

• The study found that projected improvements in production efficiency may be insufficient to meet future food demand without also increasing the total environmental burden of food production.
• Transitioning to less impactful diets would allow production efficiency to keep pace with growth in human demand while minimizing the food system’s environmental burden.
• The absence of pork in pescetarian and vegetarian diets contributes to a substantial reduction in per capita GHG emissions.
• Increased consumption of aquaculture seafood in the GDP-based diet leads to a sizable increase in required nitrogen.
• Shifting to pescetarian or vegetarian diets reduces environmental burdens relative to other diets and may even decrease all environmental burdens below current levels.
• The Mediterranean diet, which includes increased fruits/vegetables/milk and decreased cereals/beef, minimizes additional land requirements.

Limitations Noted in the Document

• The study focuses on a global scale, utilizing national-level data, which may not capture inter-country heterogeneity in diets or intra-country inequality in food access.
• The study considers a limited number of future diet scenarios.
• The study’s extrapolations of production efficiency do not account for potential effects of climate change.
• The study does not address interactions between production efficiency and consumption rates, which may lead to Jevons’ Paradox.
• The study’s estimations of additional resource requirements are conservative, assuming a linear continuation of improving production efficiencies.

Conclusion

The research underscores the urgent need for a new food revolution that integrates existing technologies and approaches with new innovations to ensure food security while minimizing environmental impacts. The study’s findings suggest that relying solely on improvements in production efficiency is unlikely to be sufficient to prevent further increases in agriculture’s environmental burden. A shift towards less impactful diets and changes in consumption patterns are crucial for achieving environmental sustainability. Dietary changes, particularly those that reduce the consumption of animal products and increase plant-based foods, offer significant potential for mitigating environmental burdens. The results indicate that the Mediterranean, pescetarian, and vegetarian diets can reduce environmental burdens, offering a pathway towards a more sustainable food system. The study highlights the need to consider the true environmental costs of food production, and to find ways to incorporate these costs into consumer choices. While sustainable intensification aims to increase food production while minimizing environmental impacts, this research demonstrates that a combined approach of dietary changes and efficiency improvements is necessary to achieve a truly sustainable and resilient food system. The implications are significant, emphasizing that realizing environmental sustainability of the global food system will require a multi-faceted approach, integrating sustainable targets and better integrating food security and environmental impacts.