BEPLS Vol 3 [6] 2014 219 | P age ©2014 AELS, INDIA
Bulletin of Environment, Pharmacology and Life Sciences
Bull. Env. Pharmacol. Life Sci., Vol 3 [6] May 2014: 219-222
©2014 Academy for Environment and Life Sciences, India
Online ISSN 2277-1808
Journal’s URL:http://www.bepls.com
CODEN: BEPLAD
Global Impact Factor 0.533
Universal Impact Factor 0.9804
ORIGINAL ARTICLE
Kinetic Equations for Aquatic Plants' Lead Absorption from
Industrial Sewage Sludge in Khuzestan
Shahram Goudarzi
1
, Mehran Hoodaji², Mahmoud Kalbasi², Payam Najafi³
1
Department of Soil Sciences, Khorasgan(Isfahan) Branch, Islamic Azad University, Khorasgan, Iran
2
Department of Soil Sciences, Khorasgan(Isfahan) Branch, Islamic Azad University, Khorasgan, Iran
3
Department of Water Engineering, Khorasgan(Isfahan) Branch, Islamic Azad University, Khorasgan, Iran
ABSTRACT
Aquatic plants can absorb nutrients and heavy metals from soil and sewage sludge. In this study, the capability of three
aquatic plant species, Typha latifolia ،Phragmites australis, has been investigated in respect of lead absorption from
sewage sludge in a hot and dry climate of Dezful. Each of the two plant species was cultured in systems; also some
systems, without planet, were considered as a control, and it was conducted in a completely randomized design and the
lead uptake of plant species in these treatments has been studied. The test included 6 pounds of sewage sludge, and 3
ponds without plant as a control group. The results showed that the lead accumulation in underground organs of both
plant species was higher than shoots. Lead accumulation in the tissues of plant species of T. latifolia was more than that
in the tissues of other species. At the end, Kinetics equations of absorption were extracted by Curve expert, 2007. The
general form of absorption equations was fitted to exponential equation, these absorption equations are: y = ae
b/t
and
y = (1-e
-bt
). In these equations, Y is the rate of heavy metal accumulation, t is time, a and b coefficients are regression
coefficients. The results represent the superiority of T. latifolia over the other plant species under study.
Key words: Lead, Typha latifolia, Phragmites australis, sewage sludge
Received 12.01.2014 Revised 25.03.2014 Accepted 12.04. 2014
INTRODUCTION
The use of sewage sludge has always been considered by researchers and experts in agriculture and
environmental section as a providing source of cheap nutrients in farmlands. By considering the
increasing population growth and thus increasing sewage, and consequently increasing the sewage
sludge, the agricultural use is one of the suitable and environmentally sound ways to prevent its
accumulation. However, due to the high concentration of heavy metals in the sewage sludge combination,
its direct consumption will cause some problems. Accumulation of heavy metals such as nickel, cadmium,
lead and other toxic substances in the soil by using sewage sludge will cause their entrance into the food
chain through the plant uptake and make toxicity. Artificial canebrake systems are those that have been
used in many parts of the world with low cost and simple technology to refine different types of sewage.
In these systems, the heavy metals existing in the sewage are removed by absorbing through aquatic
plants, chemical combination, ion exchange, adsorption by soil, and other inorganic materials [2]. The
results of a survey conducted by Vymazal [1] in Czech Republic, to determine the removal efficiency of
heavy metals from an industrial sewage with artificial horizontal pond systems showed that this system
could refine a lot of heavy metals such as copper (Cu), Chromium (Cr). P. australis and Phalaris
arundinacea were plants examined in this study. The sampling of plant organs shows that the most
decrease in Cu and Cr concentration has been respectively in plants’ roots, rhizomes, stems and leaves.
Manios et al [3] studied the effect of input concentration of heavy metals existing in sewage sludge on the
uptake of these metals through aerial and underground organs of aquatic plant specie, T. latifolia. Heavy
metals investigated in this study were Cadmium, Copper, Zinc, Nickel and Lead; the culture mediums
were irrigated with water contaminated with above mentioned metals once every two weeks, and after
10 weeks sampling of plants’ organs was done. The result showed that this plant specie has a high ability
in absorbing metal; and the accumulation of these metals in aerial organs was higher than the
underground organs. Therefore, the study of effective and environmental friendly methods for heavy