Environmental Engineering Reference
In-Depth Information
Keywords
Crude oil
·
Phytoremediation
·
Plant
·
Soil
·
Tall fescue
1 Introduction
Crude oil and its by-products are widely used by human for various reasons, such
as home heating and fueling of the vehicles. The leakage of crude oil in to soil
damages the biological systems residing in the soil including microorganisms and
plants. During the past decades, the use of petroleum products have increased and
this has resulted in the contamination of the soil and water (Bauman
1991
; Liang
et al.
2009
; Riser-Roberts
2010
; Cioni and Petarca
2011
; Liang et al.
2012
). Some
petroleum components are toxic for living organisms, however, some plants and
microorganisms are able to biodegrade the crude oil hydrocarbons into products
less toxic than the parent compounds (Eweis et al.
1998
; Al-Mailem et al.
2010
; Das
and Chandran
2010
; Thavasi et al.
2010
; Tyagi et al.
2011
; Thavasi et al.
2011
; Spei-
ght and Arjoon
2012
; Gojgic-Cvijovic et al.
2012
). Phytoremediation is on-site use
of plants and their associated microorganisms to remediate contaminated soil and
water (Cunningham et al.
1996
; Euliss et al.
2008
; Peng et al.
2009
; Infante et al.
2012
). Phytoremediation can be applied to terrestrial and aquatic environments. In
this process, the plant absorbs and breaks down organic chemicals in contaminated
soil through its metabolic processes. Various plants have been identified for their
potential to facilitate the phytoremediation of petroleum contaminated soils (Brandt
et al.
2006
; Minai-Tehrani
2008
). In many studies, grasses and legumes have been
used for their potential in this regard (Aprill and Sims
1990
; Gunther et al.
1996
;
Soleimani et al.
2010
; Njoku et al.
2012
; Cook and Hesterberg
2013
). Grass roots
have the maximum root surface area compared to other plant types and may pen-
etrate the soil to the depth of up to 3 m (Aprill and Sims
1990
; Soleimani et al.
2010
;
Sinha et al.
2013
). In this study, the effect of different concentrations of light crude
oil on the growth and germination of a in grass,
Festuca arundinacea
(Tall fescue),
was studied and the reduction of light crude oil in the soil as a contaminant in the
presence of plant was investigated.
2
Materials and Method
Light crude oil (API gravity = 40) was obtained from an oil processing factory of
Sarkan from west of Iran and added to the dry soil with concentrations of 0, 1, 3,
5, 7 and 10 % (w/w). Each sample consisted of 800 g of dry soil. Chemical fertil-
izers were added to the soil before seeding. Nitrate (NH
4
NO
3
) @ 75 mg/kg and
phosphate (KH
2
PO
4
) @ 30 mg/kg were added to all samples. Thirty seeds of Tall
Fescue were planted in each sample. All vegetated samples were prepared as three
replicates. The control samples for each concentration were also prepared as three
replicates; the control samples did not receive seeds (non-vegetated). Prior to plant-
