Biophysicochemical Characterization of Soils of Abandoned and Active Solid Waste Dumpsites in Rivers State Southern Nigeria
- September 14, 2020
- Posted by: RSIS Team
- Categories: Biochemistry, IJRIAS
International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume V, Issue III, March 2020 | ISSN 2454–6186
Wemedo, S. A.1*, Boisa, N.2, Oduah, R. N.3, Obunwo, C. C.4
1Department of Microbiology, Rivers State University, Nkpolu-Oroworukwo, Port Harcourt, Nigeria
2,3,4Department of Chemistry, Rivers State University, Nkpolu-Oroworukwo, Port Harcourt, Nigeria
*Corresponding author: Wemedo, S. A.
Abstract: – Waste generation is continuous from daily human activities, and due to lack of adequate treatment facilities, waste dumpsites are opened at designated sites. Overtime, active waste dumpsites have been closed or abandoned and new sites are created. However, there is dearth information on the comparison between the microbiological and physicochemical properties of active and abandoned waste dumpsites’ soils. This research therefore was aimed at characterizing the microbial content of active and abandoned waste dumpsite soils and assessing changes in the physicochemical properties of the dumpsite soils as to ascertain the public health concern of the two types of dumpsites. Forty soil samples were collected from the two types of solid waste dumpsites and control sites. Biological characterization of soils involved determining the counts of heterotrophic bacteria and fungi of soil samples as well as characterizing the microbial isolates using standard plate count method. Some physicochemical properties of soils were determined using standard analytical procedures. Mean ranges of physicochemical parameters were: pH 5.85±0.40 to 6.63±0.14, EC 90.38±55.92 to 625.17±356.49µS/cm, Av. P 29.41±8.99 to 54.97±19.24mg/kg, TOC 0.92±0.36 to 1.94±0.98%, TOM 2.20±0.04 to 3.42±1.69%, TN 0.02±0.01 to 0.04±0.02%, Sand 79.23±1.85 to 83.81±5.64%, Silt 5.04±2.31 to 12.3±4.44%. Clay 7.01±0.18 to 11.98±3.02%, CEC 6.68±3.08 to 12.19±5.50cmol/kg. Significant difference at p<0.05 were observed in the mean values of some physicochemical properties such as pH, EC, %TN, CEC, %sand, %clay and %silt of the sampling locations at the two depths and between control, historical and active dumpsite soils. However, some values showed no statistical significant difference. Mean ranges of microbial counts at 0–15cm and 15–30cm depths were: THB 9.4±4.39 to 22.4±5.78x105cfu/g and 13.8±7.78 to 16.1±13.45x105cfu/g, THF 2.37±0.45 to 7.1±1.85x105sfu/g and 3.9±2.29 to 6.4±2.09x105sfu/g respectively. Mean bacterial counts at the two depths were higher in control soils than the dumpsite soils, and lower in historical dumpsite soils compared to active dumpsite soils while fungal counts were higher in control soils than the dumpsites but lower in historical dumpsite soils compared to active dumpsite soils. Eleven (11) bacterial species isolated from the soil samples include Bacillus tequilensis, Bacillus pumilus, Bacillus licheniformis, Bacillus species, Pseudomonas, Raoultella ornithinolytica, Pantoa ananatis, Serratia liquefaciens, Serratia odonifera, Staphylococcus species and E. coli. All the bacterial species were found in active and historical dumpsite soils as well as in control soils except Serratia liquefaciens which occurred only in historical waste dumpsite soils, and E. coli which did not occur in the control soils. Order
