Enhancing organic waste decomposition with addition of phosphorus and calcium through different sources

Oshioname Unuofin, Frank; Siswana, Msimelelo

doi:10.1007/s40093-018-0239-1

Original Article

Enhancing organic waste decomposition with addition of phosphorus and calcium through different sources

Authors

Frank Oshioname Unuofin ¹
Msimelelo Siswana ¹

Abstract

Purpose This study assessed the constituent element in rock phosphate (RP) that is responsible for enhancing quick decomposition of cow dung–waste paper mixtures during vermicomposting.
Method Feedstock weighing 5 kg was achieved by mixing 2.16 kg shredded waste paper together with 2.84 kg cow dung sprinkled with water and then enriched with (1% P) as RP from triple superphosphate (TSP), phosphoric acid (PHA) and Ca in the form of CaCl₂ at the level supplied by RP. After mixing, they were loaded into vermireactors and inoculated with matured earthworms at a stocking density of 12.5 g worms/kg feed for the entire 56 days. The decomposition of the mixtures was then monitored by measuring maturity parameters, a germination test for phyto-toxicity and morphological properties was assessed using scanning electron microscopy (SEM).
Result Results revealed that rapid decomposition of waste was recorded where TSP was applied than RP whereas Ca-source had the least effect. A C:N ratio of 12 was achieved within 28 days where TSP was added, while RP, PHA and CaCl₂ needed 42, 56 and more than 56 days, respectively.
Conclusion It was evidently revealed from the results that P was basically the cause of the improved decomposition of the waste mixtures. To achieve quicker and well-humified enriched vermicompost with a C:N ratio of 10 within 20 days of vermicomposting, add water-soluble P sources.