MICRO AND MACRO AGRONOMIC EFFICIENCY OF NUTRIENTS RECOVERED FROM HUMAN URINE IN CORN GROWTH (Zea Mays)
Name: Regiane Pereira Roque
Type: PhD thesis
Publication date: 04/03/2022
Advisor:
Name |
Role |
|---|---|
| Ricardo Franci Gonçalves | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| Aureliano Nogueira da Costa | External Examiner * |
| Regina de Pinho Keller | Internal Examiner * |
| Ricardo Franci Gonçalves | Advisor * |
| ROSANE HEIN DE CAMPOS | External Examiner * |
| Sérvio Túlio Alves Cassini | Internal Examiner * |
Summary: The continued growth of the population has significantly increased the demand for
phosphate fertilizers in addition to the addition of waste in the environment. It has long
been known that waste sums of urban metabolism contain resources that can be
recovered for productive purposes, such as nutrients and energy. The recovery of
nutrients (nitrogen and phosphorus) from urine crystallization of struvite
(NH₄MgPO₄.6H₂O) is a practical expanding in the world. The aim of this study was to
characterize a fertilizer recycled from human urine through the chemical precipitation
of struvite in Jar test, detect the presence of possible heavy metals and assess their
efficiency. A comparison of the treatments was performed by the Average Comparison
Tests (Test of Friedman) with his post-hoc (Nemenyi) and the Mann Whitney test U.
Among the results obtained, struvite was the predominant phase in the material
(79.54%). A phase of newberyite was detected by NMR, however, NMR was not able
to identify other impurities, evidencing the need for the association of methods when it
is intended to carry out the speciation of P. Cd, Pb, Cr and Hg were below the permitted
by Brazilian legislation. In all treatments with MAP, the MS productions were higher.
Meanwhile there were no statistical differences when compared to the means of a
same treatment (significance level 0.05). P absorption was higher with MAP. Soils
treated with struvite-based fertilisers showed higher concentrations of remaining P.
RAS was low for the dosage of 30 mg of P/kg of soil. At the dosages of 80, 160 and
240 mg p/kg of soil, the RAs were above 85%, but this proportion decreased with the
320 mg dosage of P/kg of soil. The P in the soil, as well as the nutrients Na, Ca and
Cu did not show significant differences among the means of the same treatment.
However, there was a difference for Zn in the treatment of 160 mg of P/kg of soil and
for Fe, Mn and K in the treatment of 240 mg of P/kg soil. Different concentrations of
Zn, Ni, Fe, Mn, Al, Na, Mg, P, K, Ca and S were absorbed by the plants. However,
their concentrations had P, Mn, Ca and S nutrients at the same dosage. For Ni, Fe and
Al, there was a significant difference in the dosage of 80 mg of W/ kg of soil. For Zn
and Mg, the differences were in the dosages of 240 and 320 mg of soil P/kg. Finally,
for K, the difference was in the dosage of 240 mg of P/kg of soil. Struvite-based fertiliser
may be considered an alternative and safe source for the supply of nutrients to the
culture of corn due to its chemical composition supplying nutritional demand and not
feature heavy metals.
