Restauración De Suelos

J Appl Electrochem (2010) 40:1085–1093
DOI 10.1007/s10800-010-0072-3

ORIGINAL PAPER

Electrokinetic restoration of saline agricultural lands
Jung-Min Cho • Seon-Young Park
Kitae Baek

•

Received: 27 August 2009 / Accepted: 4 January 2010 / Published online: 14 January 2010
Ó Springer Science+Business Media B.V. 2010

Abstract Salinization of greenhouse soils has become a
seriousproblem in Korea because of the extensive use of
chemical fertilizers to improve crop yield. This study
investigated the feasibility of electrokinetic (EK) treatment
for reclamation of saline soil. Experiments were conducted
using voltage gradients of 1, 2, and 3 V/cm applied for 48
and 96 h. Anions such as chloride, sulfate, and nitrate were
transported toward the anode and accumulatedthere,
whereas cations were transferred toward the cathode by
electromigration. Among the various ions, the highest
removal efficiency was achieved for nitrate: [80% at 48 h
and [99% at 96 h. Chloride removal after 96 h was substantially higher than that after 48 h because the longer
period of time allowed more electrical transport via electromigration and electro-osmosis. However, the removalefficiency for sulfate and calcium did not change significantly between 48 and 96 h. Soil EC was lower than the
initial value in all soil sections at 96 h. The lowest value,
1.8 dS/m, was seen in the experiment employing a gradient
of 3 V/cm for 48 h. This study demonstrated that nitrate
can be readily removed from soil by electromigration.
Further, other ions can also be removed by EK treatment;therefore, it could be successfully used for reclamation of
saline soils.
Keywords Electrokinetic remediation Á Voltage
gradient Á Electric conductivity Á Saline soil Á Salts

J.-M. Cho Á S.-Y. Park Á K. Baek (&)
Department of Environment Engineering, Kumoh National
Institute of Technology, 77 Sanho-ro, Gumi,
Kyeong-buk 730-701, Republic of Korea
e-mail: kbaek@kumoh.ac.kr

1Introduction
Salinity has compromised approximately 7% of the
earth’s land, 20% of agricultural lands, and 50% of the
cultivated land in the world [1–4]. In agricultural lands,
the high salinity was mainly caused by overuse of fertilizers and chemical pesticides to improve the crop
productivity, and insufficient irrigation [5–9]. The use of
greenhouses has dramatically increased due to the
increase indemand for greenhouse crops and because of
the large yields that can be achieved [10]. Greenhouses in
Korea account for 3.5% of the total agricultural area.
Repeated cultivation is generally performed and manure
is spread over the field. The closed system of a greenhouse is designed to create a particular environment in
which a high inside temperature is maintained and rainfall is intercepted[11]. However, consequently, salts from
the fertilizers do not percolate into the subsoil and are not
washed away by the rain as they would in an open field.
Furthermore, the high greenhouse temperature increases
evaporation, causing salt accumulation at the soil surface.
Moreover, the repeated cultivation accelerates soil salinization. Many species of salts exist in ionic form in the
soil:cations include sodium, calcium, potassium, magnesium, etc.; anions include chloride, sulfate, nitrate, and
phosphate, etc. A certain quantity of salts is essential for
plant growth, and all soils contain some salts in pore
water. However, an excess amount of salt in soil can
have a detrimental effect on plant growth, including
reduced water availability, osmotic adjustment, and
nutrientuptake and also tissue injury [6]. Excess nitrate
can have adverse effects not only on plants, but also on
humans, e.g., methemoglobinemia (blue baby syndrome)
and epidemiological gastric cancer [12, 13]. Further,
surplus Na? causes the virulence to plants and degrades

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soil physical properties, and Cl- can be toxic. The
salinity of soil can be expressed in term of its...