Browsing by Author "Anyika, L. C."

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    GIS and MATLAB modeling of criteria pollutants: A study of Lower Onitsha Basin during rains
    (Journal BiNET Scientifc Publishing, 2018-10-14) Anyika, L. C.; Alisa, C. O.; Nkwoada, A. U.; Opara, A. I.; Ejike, E. N.; Onuoha, G. N.
    The study of air pollutants SO2, NO2 and PM10 in lower Onitsha basin, a densely populated city was performed using GPS and Matlab modeling. The pollutants were studied in nine specific locations for 3 months of rains over 3 consecutive years with each georeferenced. The Matlab pollution model was generated by integrating the spatial database and measured pollution attributes database using a polynomial expression. SO2 highest concentration (141 µg/m3) peaked in Upper Iweka at sampling point 1 before dispersing to lower concentrated regions in Awada and Resthouse. NO2 peaked at 207 µg/m3 in Upper Iweka at sampling point 3 and driven by wind towards Borromeo area to very low concentration of 38 ug/m3. The PM10 peaked in Upper Iweka (180 µg/m3) and driven by rains towards Borromeo before increasing again in concentration levels at Awada. The AQI showed that SO2 pollutants had acceptable air quality at all sampling points while NO2 and PM10 air quality affected sensitive groups. SO2 concentration levels exceeded the National air quality standard in Nigeria (NAQS) while NO2 and PM10 were below the NAQS standard. The GIS plot showed that 3 metrological forces were driving pollutants from Upper Iweka and Awada to other sampling areas in the order of SO2> NO2> PM10. The Matlab wind speed plot showed that there was an upward wind in upper Iweka driving the pollutants towards dispersal at some other region. Thus, Upper Iweka is an active point source pollution area and dispersed to Borromeo and Awada by scavenging rains under prevailing wind speed, wind direction and humidity. Hence calls for improved monitoring and regulation to address poll.
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    Spatio-temporal study of criteria pollutants in Nigerian city
    (U. P., 2020-06-29) Anyika, L. C.; Alisa, C. O.; Nkwoada, A. U.; Opara, A. I.; Ejike, E. N.
    Aims: An investigation of characteristic long term air pollutants known for temporal and spatial behaviors was conducted due to increased pollution scenarios in Nigerian cities as a result of deprived environmental enforcement of statutory obligations. Study Design: One of the worlds’ most polluted cities (Onitsha lower basin) in Nigeria was selected for spatio-temporal study of three criteria pollutants combined with GIS and MATLAB alongside associated meteorological conditions during harmattan. Methodology: 72-hourly analyses of the nine different locations having 4 sampling sites and 500 meters apart were done from December to February which generated over 19, 440 experimental data per quarter of each annual study. Results: Upper Iweka/Nitel area recorded the highest concentration of SO2 pollutant at (94.2 µg/m3) due to longer residence times and low wind mixing height. Borromeo hospital showed the least active NO2 region but converges at points 1 due to North-east wind dissimilar to sampling points 1 having the lowest PM10 distribution. Measured temperature parameter correlates inversely with relative humidity and precipitation. The GIS spatial representation corresponded to temporal variability of gaseous and particulate pollutants. Conclusion: All sampled areas had AQI above 50; hence the study identified SO2, NO2, and PM10 as Primary pollutants of Onitsha lower basin.