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Impact of
soil amendment on phytotoxicity of a 5-month old waste
engine oil polluted soil
Ikhajiagbe Beckley1* and Anoliefo Geoffery
Obinna2
1Raw Materials Research and
Development Council, Abuja, Nigeria.
2Department of Plant Biology and
Biotechnology, University of Benin, Benin City. Nigeria.
*Corresponding author. E-mail:
ikhaj@yahoo.com.
Accepted
20 June, 2010 |
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The present study investigated the effects
of soil amendment on the remediation of waste engine oil (WEO)
polluted soil, as well as the eventual phytotoxic effects of
remediated amended soil on some growth parameters of cowpea.
There was significant decrease in heavy metal concentration
of the polluted soil more than average, nine months after
amendment. There was also total remediation of some PAH
compounds (benzo(a)anthracene, benzo(a)pyrene,
benzo(b)fluoranthene, benezo(g,h,i)perylene,
benzo(k)fluoranthene, chrysene, dibenzo(a,h)anthracene,
fluoranthene, fluorene and Indeno(1,2,3-c,d)pyrene).
Achromobacter sp, Clostridium sp, Sarcina
sp and Micrococcus sp were prevalent bacteria species
found in the polluted soils, while prevalent fungi species
included Aspergillus niger, Penicillium sp,
Geotrichum sp and Trichoderma sp. The
actinomycete Nocardia sp was prevalent as well.
Ecological risk factor initially posed by the presence of
heavy metals in the unamended soil was significantly reduced
to safe levels. Phyto assessment
of the polluted soil was carried out just before soil was
amended with saw dust and results showed that virtually all
the cowpea seedlings died within 2 weeks; only those
seedlings in unpolluted soils survived. Nine months after
soil was amended, all cowpea plants survived up to fruiting.
The present study also showed that cowpea was able to
bioaccumulate heavy metals into harvestable parts, though
bioaccumulation quotients calculated showed that these
accumulations were not significant.
Key words:
Penicillium
sp, Geotrichum sp, phytotoxic, fluoranthene,
fluorine. |
