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Abstract Waste from the human food system includes a large quantity of nutrients that pose environmental and human health risks. If these nutrients can be captured and repurposed, they could potentially offset synthetic fertilizer demands. This study reviews several technologies—including anaerobic digestion, hydrothermal carbonization (HTC), and composting—that can be used to process wastes from the human food system. This study also assesses the quantity of nutrient resources that are available from wastes, including food waste, biosolids, manure, and yard waste. Three geographic scales were analyzed. At a national level in the United States, up to 27% of nitrogen and 33% of phosphorus demands for agriculture could be met with wastes from the human food system, primarily from food waste and biosolids. Some rural localities have a greater potential for circular economies of nutrients in the food system, with the potential to meet 100% of nitrogen and phosphorus fertilizer demands using waste nutrients, as in the case of Athens County, Ohio. Benefits of offsetting synthetic fertilizer use with waste nutrients include reduced greenhouse gas (GHG) emissions, with up to 64% reduction in GHG emissions per unit of nitrogen fertilizer produced with HTC.
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Scenario analysis of nitrogen surplus typologies in Europe shows that a 20% fertilizer reduction may fall short of 2030 EU Green Deal goals
Abstract The Farm to Fork (F2F) Strategy under the Green Deal aims to halve nutrient losses by 2030 in the European Union (EU). Here, using the nitrogen surplus as an indicator for nitrogen losses in agricultural areas, we explore a range of scenarios for nitrogen surplus reduction across EU landscapes. We identify four nitrogen surplus typologies, each responding differently to input reduction. A 20% decrease in synthetic fertilizer alone is projected to reduce the nitrogen surplus by only 10–16%, falling short of F2F goals. Specific top-down scenarios such as reducing synthetic fertilizer by 43% and animal manure by 4%, coupled with improved technological and management practices, can achieve a reduction of up to 30–45% in nitrogen surplus. Among the most ambitious scenarios, only a handful of EU countries (four to five) may meet the intended F2F nitrogen pollution targets. Achieving F2F goals requires region-specific strategies to reduce nitrogen use while improving efficiency and sustaining productivity.
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- Award ID(s):
- 2330502
- PAR ID:
- 10647350
- Publisher / Repository:
- Nature Food
- Date Published:
- Journal Name:
- Nature Food
- Volume:
- 6
- Issue:
- 8
- ISSN:
- 2662-1355
- Page Range / eLocation ID:
- 787 to 798
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s43016-025-01210-2
