| Liquid manure from livestock production systems is a major source of nitrogen and phosphorus release from nutrient cycles and a cause of ecosystem eutrophication. Duckweeds, small aquatic plants, may be used to recover N and P from livestock slurry while producing high-quality protein feed. In order to assess N and P uptake efficiency and utility for fish feed, two duckweed species, Landoltia punctata and Spirodela polyrhiza, were grown in controlled climate chambers on two nutrient-rich media: diluted (1:10) cattle slurry and mechanically filtered household sewage. Treatments were in triplicate, each running in four cycles with fresh substrate (one week each). Spirodela polyrhiza exhibited the strongest growth (96 g fresh matter m−2 day−1) and highest... |
