Shrivastava, Vaibhav
- Institutionen för energi och teknik, Sveriges lantbruksuniversitet
Sammanfattning
Circular agriculture reclaims nutrients from waste streams to reduce fertilizer imports, mitigate environmental impacts, and close material loops. This review evaluates the agronomic performance of nitrogen, phosphorus, and potassium products recovered from wastewater, crop residues, and manure compared with conventional fertilizers. A structured literature survey identified 85 pot and field trials published between 2010 and 2024, covering ammonium salts, struvite, ashes, compost, digestate, biochar, hydrochar, and biostimulants. Ammonium sulfate and nitrate consistently matched synthetic yields (95-105%) due to their solubility and immediate N availability, while aqueous ammonia showed variable results depending on application timing and soil pH. Struvite and phosphorus-rich ashes performed best (90-100%) in neutral to slightly acidic soils, whereas organo-mineral phosphate fertilizers (85-95%) were less effective in alkaline soils. Potassium-rich ashes and waste mica were effective (80-95%) in soils with moderate cation exchange, though mica underperformed (60-75%) in coarse soils. Biochars and hydrochars improved soil water retention and nutrient exchange, yielding 90-110% of synthetic performance, while biostimulants increased yields by 8-20%. Recovered products demonstrate agronomic equivalence while offering co-benefits for soil health, waste management, and circular economy goals. Future work should prioritize long-term field validation, techno-economic analysis, and regulatory integration to enable large-scale adoption.
Nyckelord
bio-based fertilizers; manure; wastewater; ammonium salts; struvite; biostimulants
Publicerad i
Nitrogen
2025, volym: 6, nummer: 3, artikelnummer: 80
Utgivare: MDPI
SLU författare
UKÄ forskningsämne
Vattenbehandlingsbioteknik
Publikationens identifierare
- DOI: https://doi.org/10.3390/nitrogen6030080
Permanent länk till denna sida (URI)
https://res.slu.se/id/publ/143971