Demand-Driven Model for Global Phosphate Rock Suggests Paths for Phosphorus Sustainability

Area of Science:

• Agricultural Science
• Environmental Science
• Resource Management

Background:

• Phosphorus (P) is an essential, non-substitutable fertilizer for global food production.
• Current P supply chains experience significant losses, leading to environmental degradation.
• Sustainable P management is critical for future food security.

Purpose of the Study:

• To model the global phosphorus production sensitivity to various food system interventions.
• To identify the most impactful strategies for reducing phosphorus demand.
• To assess global human carrying capacity based on alternative phosphorus sources.

Main Methods:

• Utilized a demand-driven substance flow model.
• Analyzed interventions including animal fraction in diet (AFD), manure use efficiency (MUE), animal yield (YA), phosphorus use efficiency (PUE), food waste fraction (FWF), food waste recycling (FRE), and human waste recycling (WRE).

Main Results:

• Animal fraction in diet (AFD) and animal food yield (YA) were identified as the most influential interventions, interacting with PUE and MUE.
• A critical threshold exists for AFD and YA, below which increased mining becomes necessary.
• Reducing food waste (FWF) is approximately 80 times more effective than recycling food waste (FRE) in lowering P demand.

Conclusions:

• Optimizing AFD and YA, alongside PUE and MUE, is key to sustainable phosphorus management.
• Reducing food waste offers a highly effective strategy for mitigating phosphorus demand.
• Non-mining P sources could support 2.5 billion people, potentially sustaining 14.7 billion with comprehensive intervention implementation.