Effects of Biostimulation and Bioaugumentation on Microbial Growth and Bioremediation of Hydrocarbon contaminated soils
Tudararo-Aherobo, Laurelta
, Okorhi-Damisa F.Beatrice
Hydrocarbon polluted Soil, Hydrocarbon utilizing bacteria, Remediation
Fossil oil spillage is a common source of soil contamination in Nigeria. In severe cases, it can lead to loss of lives, damage to farmlands and reduction of biodensity and biodiversity of the biotic components of the impacted environment. While natural breakdown of pollutants occurs, it is important to control hydrocarbon pollution in order to prevent an increase in the contamination leading to destruction of the ecosystems. However the aim of this study is to identify the effects of biostimulation and bioaugmentation on microbial growth and bioremediation of hydrocarbon contaminated soils. Pristine garden soil was contaminated with three concentrations of Bonny light crude oil (100,00mg/kg or 10%,10,000mg/kg or 1% and 1,000mg/kg or 0.1%), while food wastes compost was used as the biostimulant to enhance the bioremediation of the contaminated soils. Three identified indigenous bacteria species (Bacillus velezensis, Lysinibacillus pakistanensis and Stenotrophomonas species) were used as a consortium to bioaugment the bioremediation process. Microbial and physicochemical analyses were conducted using standard methods, while metals were analysed using Inductively Coupled plasma Atomic emission spectroscopy (ICP-AES) and atomic absorption spectrometry (AAS) analytical techniques that measure the concentrations of elements qualitatively and quantitatively. The hydrocarbon impacted and unimpacted garden soil samples had mean pH values of 5.75±1 and 7.84±1respectively, while the compost had a pH value of 8.00±1.0. The values of nitrate, phosphate, calcium (ca) magnesium (Mg) and potassium (k) present in the various soils are; 0.091ppm, 0.244ppm, 0.803545%, 0.020542% and 0.269008% for the impacted soil sample and for the unimpacted 1.335ppm 0.287%, 0.441135%, 0.01256% and 0.357033% was recorded respectively. Composite microbial culture (CMC) isolated from the hydrocarbon impacted soil and organic compost from food wastes were combined in three different concentrations of Bonny light crude oil as follow: 10 %( 100,000mg/kg), 1 %( 10,000mg/kg) and 0.1 %( 1000mg/kg). For the control, 10% and 1% of crude oil was used to monitor the process. The set up was monitored for 16 weeks with GC-FID to monitor the total petroleum hydrocarbon (TPH) removal. The data obtained from the study shows that biostimulation using composite microbial culture and organic compost could lead to a drastic reduction of the TPH in the hydrocarbon polluted soil.The data obtained from the GC-FID revealed that concentration A (10%) recorded 13.00±00.71mg/kg, B (1%) recorded11.56±0.01mg/kg, while C(0.1%) recorded1.77±0.01mg/kg. 1% of the control recorded 27.84±0.01mg/kg, whereas 10% recorded 200.08±0.16mg/kg by the end of the experiment. However the microbiological analyses of the impacted soil revealed that the soil had appreciable mean population of hydrocarbon utilizing bacteria counts (HUB) is 106.67±4.51 (cfu/g), 93.00±4.00 (cfu/g) and 87.67±7.51 (cfu/g) and total heterotrophic bacteria count (THB) 110.00±20.00, 109.33±1.53 and 105.00±15.00 (cfu/g) with the fossil oil concentrations of 10%, 1% and 0.1% respectively. However, the difference between THB and HUB counts was observed to be minimally insignificant, which suggest that most of the microorganisms present in the various polluted sample sites are hydrocarbon degraders that can withstand the concentrations of hydrocarbons and also use them as source of carbon. The impacted soil amended with CMC and Compost has shown from the study to stimulate the growth of indigenous oil degrading micro biota and enhance the remediation of hydrocarbon polluted soils. This is a win-win situation of proper management of organic wastes while enhancing removal of hydrocarbons from polluted soils.
"Effects of Biostimulation and Bioaugumentation on Microbial Growth and Bioremediation of Hydrocarbon contaminated soils", IJSDR - International Journal of Scientific Development and Research (www.IJSDR.org), ISSN:2455-2631, Vol.8, Issue 3, page no.1086 - 1095, March-2023, Available :https://ijsdr.org/papers/IJSDR2303180.pdf
Volume 8
Issue 3,
March-2023
Pages : 1086 - 1095
Paper Reg. ID: IJSDR_204685
Published Paper Id: IJSDR2303180
Downloads: 000347298
Research Area: Life Sciences
Country: Warri, Delta, Nigeria
ISSN: 2455-2631 | IMPACT FACTOR: 9.15 Calculated By Google Scholar | ESTD YEAR: 2016
An International Scholarly Open Access Journal, Peer-Reviewed, Refereed Journal Impact Factor 9.15 Calculate by Google Scholar and Semantic Scholar | AI-Powered Research Tool, Multidisciplinary, Monthly, Multilanguage Journal Indexing in All Major Database & Metadata, Citation Generator
Publisher: IJSDR(IJ Publication) Janvi Wave
