Authors :
I. J. Udom; E. S. Udofia; S. A. Nta; G. A. Usoh; E. O. Sam
Volume/Issue :
Volume 8 - 2023, Issue 9 - September
Google Scholar :
https://tinyurl.com/49v76zms
Scribd :
https://tinyurl.com/4pss4cjz
DOI :
https://doi.org/10.5281/zenodo.10153737
Abstract :
A mathematical model for predicting the
reduction of nitrogen and phosphorus concentrations in
horizontal subsurface flow constructed wetlands was
developed. The model considered the piggery wastewater
input, storage, plant use and nutrient output to the
environment is predominantly through nitrogen
denitrification. Nutrient release from plant litter was not
considered an influence on the constructed wetland
because the young plants were picked for fodder and,
contamination from rainfall and groundwater was
considered insignificant. The adjustment and
authentication of the model was carried out by separate
data sets. Nutrient attenuation followed exponential
trend during the period followed by stability contingent
on the decay coefficient. Simulated parameters
correlated highly with the observed values with R=
0.8940 for nitrogen and 0.9518 for phosphorus
respectively. ME of 0.211 and 0.139, RMSE of 0.32 and
0.18, RE of 24 and 12%, model efficiencies of 64 and
37% and index of agreements of 0.6527 and 0.8676 for
nitrogen and phosphorus respectively. The linear
regression coefficients appear good for a natural system
under environmental influences.
Keywords :
Piggery Wastewater, Horizontal-Subsurface- Flow-Constructed-Wetlands, Pollution, Water Quality, Nutrients.
A mathematical model for predicting the
reduction of nitrogen and phosphorus concentrations in
horizontal subsurface flow constructed wetlands was
developed. The model considered the piggery wastewater
input, storage, plant use and nutrient output to the
environment is predominantly through nitrogen
denitrification. Nutrient release from plant litter was not
considered an influence on the constructed wetland
because the young plants were picked for fodder and,
contamination from rainfall and groundwater was
considered insignificant. The adjustment and
authentication of the model was carried out by separate
data sets. Nutrient attenuation followed exponential
trend during the period followed by stability contingent
on the decay coefficient. Simulated parameters
correlated highly with the observed values with R=
0.8940 for nitrogen and 0.9518 for phosphorus
respectively. ME of 0.211 and 0.139, RMSE of 0.32 and
0.18, RE of 24 and 12%, model efficiencies of 64 and
37% and index of agreements of 0.6527 and 0.8676 for
nitrogen and phosphorus respectively. The linear
regression coefficients appear good for a natural system
under environmental influences.
Keywords :
Piggery Wastewater, Horizontal-Subsurface- Flow-Constructed-Wetlands, Pollution, Water Quality, Nutrients.
