Engineering · Biomedical Engineering
A field study found that urea delivered in clay-and-biopolymer composites with phosphorus- and zinc-releasing bacteria improved nutrient levels in wheat and maize. The treatments also reduced cumulative nitrous oxide emissions by up to 29% compared with a full conventional urea application.
Hydrogen peroxide-treated biochar made from waste tyres removed 99% of phosphorus from a simulated wastewater solution, compared with 20% for untreated tyre biochar. After capturing phosphorus, the treated material was used in nutrient-poor soil, where maize biomass was nearly three times higher than with untreated material or no added fertiliser.
A study tested nano-hydroxyapatite, a calcium-and-phosphorus mineral, as a leaf spray for phosphorus-deficient barley. The particles released phosphorus gradually, but uptake varied with plant species, humidity and spray properties.
