Open Journal of Soil Science, 2012, 2, 44-49 Published Online March 2012 (
Analysis of Macro and Micronutrients in Soils from
Palestine Using Ion Exchange Membrane Technology
Zaher Barghouthi1, Sameer Amereih2, Basel Natsheh2, Mazen Salman2*
1Dpartment of Natural Resources Research, National Agricultural Research Center (NARC), Jenin, Palestine; 2Palestine Technical
University-Kadoorie, Tulkarm, Palestine.
Email: *
Received December 15th, 2011; revised January 16th, 2012; accepted January 30th, 2012
Ion Exchange membrane technology (IEM) is a method that allowed a single extraction process and a single subsequent
measurement of different elements that are available in soil. The values of the available forms of the different macro-
and micronutrients obtained by IEM extraction were compared with the values of the soluble form obtained by conven-
tional extraction methods. In surface soil sample, the concentrations of available potassium, nitrate, phosphate, iron and
boron were 37.7 mg·kg–1, 17.5 mg·kg–1, 3.6 mg·kg–1, 171.0 µg·kg–1, and 4.2 µg·kg–1 respectively were greater than that
of soluble forms of the same elements which were 7.0 mg·kg–1, 9.2 mg·kg–1, 0.4 mg·kg–1, 109.0 µg·kg–1, and 1.9 µg·kg–1
Keywords: Ion Exchange Membrane; Available Ions; Soil; Nutrients; Palestine
1. Introduction
Soil is a diverse complex that can be defined as a mixture
of minerals and organic materials, which are capable of
supporting plant life [1,2]. Soil contains 13 out of 16 dif-
ferent elements essential for plant growth [3]. However,
only small amounts of nutrients are available for plants
[4]. Nutrients become available through mineral weath-
ering and through decomposition of organic matter into
inorganic mineral which are absorbed by plants in the
form of ions [2,4,5]. Traditionally, an assessment of the
nutrient status in the soil requires a separate extraction
and measurement process for most elements; this is cost-
ly process in terms of both time and labor [6]. In the last
decades Ion exchange resin has been used to assess the
availability of plant nutrients where anion and cation ex-
change resins are used in numerous ways in soil and plant
analysis [7,8]. The method simulates removing ions from
soil by plant roots to prevent equilibrium of ions between
the solid and the solution phases [9,10]. A major problem
in using bead resins is the difficulty in their separation
from the soil following the extraction [9,11].
Ion exchange membrane technique (IEM) was devel-
oped as an alternative to chemical extraction methods to
measure nutrients bioavailability [10,11]. In addition to
its simplicity, rapidness and accuracy compared to other
existing methods, the technique was found to be highly
suitable for soil testing because multi-element in soil can
be tested [9,11]. Other advantages of IEM include greater
sensitivity to environmental conditions, the potential abi-
lity to mimic nutrient uptake by roots, no diffusion prob-
lem due to its flat structure and minimal disturbance to
soil structure [12]. IEM involves disaggregation of soil by
shaking in water during 15 minutes with a glass marble,
the elements transfer from the soil to the AEM and CEM
during a 16 hours shaking period, removing of the mem-
brane from the soil, and finally extracting the elements
from the membrane (elution). IEM extraction method al-
low single extraction process and a single subsequent mea-
surement of the soil available nitrate, phosphate, sulfate
by IC, calcium, magnesium, total phosphorous, and heavy
metals by inductive coupled plasma (ICP), sodium and
potassium by flame photometer, and ammonium by UV/
Commercial anion exchange resin are generally found
in the chloride (Cl) ion form while cation resin are usu-
ally commercialized in the hydrogen (H+) ion form [11].
The aim of this work is to use IEM technology for si-
multaneous determination of soluble and available forms
of plant micro and macronutrients in surface and subsur-
face Palestinian soils.
2. Materials and Methods
2.1. Materials
Anion exchange membrane (AEM) and cation exchange
*Corresponding author.
Copyright © 2012 SciRes. OJSS
Analysis of Macro and Micronutrients in Soils from Palestine Using Ion Exchange Membrane Technology 45
membrane (CEM) were provided by BDH (55164-2S and
55165-2U, respectively). Except where stated, all chemi-
cals were of analytical reagent grade. Distilled water
(18.2 M·cm) was used for ion chromatography (IC) mea-
2.2. Soil Samples
Soil samples were collected from two depths (0 - 30 cm
and 30 - 60 cm) from the agricultural station, National
Agriculture Research Center (NARC), Jericho, in the Jor-
dan Valley in the eastern side of the West Bank. The do-
minant soil texture in Jericho is sandy loam [13]. The pH
of the surface soil samples was measured after suspend-
ing the soil in water (1:1 w/v). The samples were air-dried
and sieved using 0.3 mm sieve.
2.3. Extraction of Nutrients
Soil samples (10 g each) were transferred to 250-ml Er-
lenmeyer flask containing 100 ml of double distilled wa-
ter. Each sample was shaken for 30 minutes at 100 rpm on
a rotary shaker. The solution was filtered using Whatman
#1 filter paper and the filtrate was then passed through
0.2 µm filters.
2.4. Extraction of Available Form of Nutrients
CEM and AEM sheets were cut into strips (2 × 6.25 cm).
Two strips of CEM and another two strips of AEM were
dipped in 250-ml Erlenmeyer flask containing 10 g of
soil dissolved in 100 ml of distilled water (18.2 M·cm).
The flask was placed on shaker at 100 rpm for 16 h. Ions
were then eluted by shaking the strips in 20 ml of 0.1 M
HCl for 3 h at 100 rpm. The eluent was taken for ions in-
strumental measurements and the strips were regenerated
in 100 ml sodium bicarbonate (0.5 M) on electronic shaker
(2 hours, 100 rpm) and stored in deionized water prior to
be reused.
2.5. Total Amount of Nutrients
The total amount of sodium, potassium, calcium, magne-
sium was determined by digesting soil sample using Mi-
crowave Accelerated Reaction System Model MARS 5.
The soil (0.5 g) was suspended in 10 ml distilled water
containing concentrated HNO3 (5 ml), HF (4 ml), and HCl
(1 ml) in digestion vessel. Digestion was done for 20 mi-
nutes at 210˚C. After that 30 ml of 30% boric acid were
added to each vessel and the digestion was continued for
5 minutes at 210˚C.
2.6. Extractable Sodium and Potassium
Sodium and potassium were extracted according to the
method of Richards 1954 [14]. Five grams of soil were
suspended in 33 ml of ammonium acetate in 100 ml ele-
mentary flask and shacked for five minutes at 100 rpm.
Extract was filtered through Whatman #1 filter paper and
transferred to 100 ml volumetric flask. The volume of the
extract was adjusted to 100 ml with ammonium acetate
solution, and filtered by 0.2 µm filter [14].
2.7. Instrumental Analysis
Soluble, available, extractable, and total potassium and
sodium forms were measured using Jenway flame photo-
meter (Clinical PFP7). The amount of potassium and so-
dium in mg·kg–1 was determined according to a calibra-
tion curve of potassium and sodium respectively. The
VARIAN VISTA-Charged Coupled Device Axial simul-
taneous Inductively Coupled Plasma-Atomic Emission
Spectrometer (VISTA CCD-AES) with concentric nebu-
liser was used for the analysis of soluble, available and
total calcium, magnesium, phosphorous, and heavy met-
als. Anions including nitrate, sulfate, and phosphate were
measured using ion exchange chromatography (IC) sys-
tem (Dionex 500) consisting of GP50 gradient pump, ED
40 electrochemical detector, and anion self regenerating
suppressor. The stationary phase was IonPac AS11-HC
analytical column, 2 mm (P/N 52961) while the mobile
phase was 30 mM hydroxide solution (BAKER ANA-
LYZED Reagent) with constant flow at 0.38 ml·min–1.
Soluble and available ammonium was determined ac-
cording to Berthelot analytical procedure [15,16] using
PERKIN ELMER UV/VIS Spectrophotometer. Untritro-
nic-OR (Selecta P) thermostat was used as an electronic
shaker. Soil pH was measured by 3310 JENWAY pH
3. Results and Discussion
In past few decades, soil testing has been plagued by
many problems that defy accuracy. These problems can
be overcome using IEM methodology where the amount
of recently nutrients that are available to the plants can
be determined.
3.1. Macronutrients
3.1.1. Potassium
Potassium is an essential macronutrient for plant growth
and development as well as for many plant functions [17,
18]. Testing potassium availability in soil plays the major
role in estimating fertilization requirements. Potassium
has four soil forms: solution, exchangeable, non-exchan-
geable, and mineral. The water soluble and exchangeable
forms represent the available fraction of potassium. Whe-
reas non exchangeable and mineral potassium forms are
known to be slowly available unavailable [19]. Potassium
availability is a complex situation; depletion of one form
shifts the equilibrium between forms to replenish it (i.e.
Copyright © 2012 SciRes. OJSS
Analysis of Macro and Micronutrients in Soils from Palestine Using Ion Exchange Membrane Technology
Non-Exchangeable K Exchangeable K Soil Solu-
tion). Potassium uptake by plants is governed by the rate
of transport from the bulk soil to the root via diffusion
[20]. It is expedient to measure a parameter that is closely
related to diffusion. This might be achieved by measuring
the concentration of soil potassium in the solution and
exchangeable forms.
Figure 1 shows the amount of potassium in soluble,
exchangeable, extractable, and available forms measured
in soil samples at 0 - 30 and 30 - 60 cm sub surfaces. Ex-
tractable potassium represents the available form which
was measured by using ammonium acetate extraction me-
thod [14]. In some soils (e.g. calcareous) can be estima-
ted as the sum of the soluble and exchangeable forms of
potassium [21]. In this study the exchangeable potassium
(29.3 mg·kg–1) was calculated from the difference be-
tween the extractable (36.3 mg·kg–1) and the soluble (7
mg· k g –1) forms. Available potassium was measured using
IEM extraction. The available potassium form reflects
soluble and exchangeable forms. Our results showed that
the available potassium which was measured using the
IEM in surface and subsurface soil samples was 37.7 and
27.3 mg·kg–1, respectively. The total potassium in both
samples measured using flame photometer was 167 ± 2.7
and 172.4 ± 3.1 mg·kg–1 respectively.
3.1.2. Nitrogen
In terms of its requirement and management in the field,
nitrogen is the most important nutrient for all crop plants
[22]. The availability of nitrogen is closely associated
with plant productivity [23,24]. Nitrogen is used by
plants in two forms, ammonium (4-N) and nitrate
(3-N) [25]. Nitrate is the dominate form of mineral
nitrogen available for plant use [26,27]. The sum of the
two forms constitutes the pool of plant-available nitrogen
[21]. Several laboratory methods have been developed to
assess nitrate availability. Most of these methods are in-
sensitive to environmental factors that influence the soil
nitrogen such as temperature and moisture [12]. IEM is a
suitable alternative to overcome environmental sensitiv-
ity conditions. In the present work, both soluble and avai-
lable forms of nitrate were extracted by IEM and meas-
ured by ion exchange chromatography (IC) using Dionex
500 system. Soluble and available forms of ammonium
were measured colorimetrically using spectrophotometer.
The amount of soluble and available nitrate and ammo-
nium are given in Table 1. Our results revealed that the
available amount of nitrate and ammonium in both sur-
face and subsurface soil were greater than that of the
soluble amount.
3.1.3. Phosphorou s
The concentration of available form of phosphorous in
soil is very low [21]. Determination of index of available
Figure 1. Soluble, exchangeable, extractable, and available
forms of potassium in surface (0 - 30 cm) and subsurface
(30 - 60 cm) soil samples measured by flame photometer in
mg·kg–1. The value of each form in the figure is the average
of nine replicates.
Table 1. Soluble and available forms of macronutrients in
surface (0 - 30 cm) and subsurface (30 - 60 cm) soil in mg·kg–1.
Each value in the table is the average for nine replicates.
Soluble Available Total
0 - 30 (cm)30 - 60 (cm) 0 - 30 (cm) 30 - 60 (cm)
Nitrate 9.2 ± 0.25.6 ± 0.1 17.5 ± 0.3 10.2 ± 0.142.5
Ammonium3.6 ± 0.33.1 ± 0.2 5.0 ± 0.4 3.5 ± 0.315.2
Phosphate0.4 ± 0.10.22 ± 0.04 3.6 ± 0.2 2.9 ± 0.27.12
Sulfate 21.5 ± 0.39.7 ± 0.2 76.2 ± 1.2 44.7 ± 1.4152.1
Calcium 20.4 ± 0.516.5 ± 0.2 69.5 ± 2.1 69.8 ± 1.3176.2
Magnesium5.6 ± 0.34.8 ± 0.1 11.9 ± 0.3 12.1 ± 0.234.4
phosphorous is still a matter of interest [25]. The pool of
bioavailable phosphorous is indexed by extraction of a
portion of labile pool of inorganic phosphorous using che-
mical extractants such as Bray 1, Mehlich 1 or 3, and
Olsen’s solution [10,28]. In the present work, the avail-
able form of phosphate was tested (Table 1). The amount
of phosphate available, in surface and subsurface soils,
which was measured using IC system was 3.6 mg·kg–1
and 2.9 mg·kg–1 respectively. The low values of phos-
phate indicate phosphorous deficiency. It is well known
that phosphorous is considered deficient when the con-
centration of available form of phosphorous is less than
6.0 mg·kg–1.
3.1.4. Sulfur
Sulfate is one of the most commonly monitored anions in
Copyright © 2012 SciRes. OJSS
Analysis of Macro and Micronutrients in Soils from Palestine Using Ion Exchange Membrane Technology 47
soils and natural waters. In soil extracts, sulfate is a mea-
sure of the available sulfur status [29]. Sulfate is sub-
jected to leaching due to its high solubility. Therefore, it
is usually found at variable depths. Our data reveal that
the available amount of sulfate is greater than that of the
so- luble amount (Table 1).
3.1.5. C alcium an d M agnesium
Calcium and magnesium are available as exchangeable
cations (Ca2+ and Mg2+). The amount available of both
elements is importantly related to mineral weathering and
degree of leaching [30].
In the present work the different fractions of calcium
and magnesium were measured using ICP instrumental
system. The available fractions of both calcium and mag-
nesium, in the surface and subsurface soils, were greater
than that of the soluble forms. Compared to calcium, ma-
gnesium is less strongly absorbed to cation exchange sites.
Thus much less available magnesium exists in soils and
magnesium deficiencies have been observed frequently.
The total amounts in the surface and subsurface soils of
calcium were 2142.0 ± 4.9 mg·kg–1 and 2120.0 ± 14.8
mg·kg–1, respectively and the amounts of magnesium were
165.6 ± 1.6 mg·kg–1 and 160.9 ± 4.8 mg·kg–1, respec-
3.2. Micronutrients
The pH is a key factor that affects the availability of the
micronutrient. Except for molybdenum, availability of mi-
cronutrients decreases at higher pH and increased soil cal-
careousness due to adsorption precipitation reactions [21,
31]. It was found that the pH of soil under investigation
was around 8. In high acidic soils, there is a relative abund-
ance of iron, manganese, zinc, and copper ions, which
are considered to be toxic to plants. In the present work,
IEM was used successfully to determine the amount (in
µg·kg–1) of micronutrients cations including soluble and
available forms of iron, manganese, cupper, and zinc in
both surface and subsurface soils (Figure 2). Cobalt ca-
tion was not detected in the soil under investigation. Our
results indicated that the concentration of micronutrients
in surface soils was lower than that in the subsurface soil
samples (Figure 2).
Unlike cations, micronutrient anions are quite different
chemically, thus little similarity would be expected in
their reaction with soil. Boron was measured efficiently
by IEM. The soluble and available boron in surface soil
samples was 1.9 ± 0.3 µg·kg–1 and 4.2 ± 0.3 µg·kg–1, re-
spectively, while soluble and available boron in subsur-
face soils was 1.7 ± 0.2 µg·kg–1 and 3.2 ± 0.1 µg·kg–1,
respectively. Results of the current work demonstrated
that the concentration of boron is within acceptable range
for plant growth. In fact, when soil boron levels are less
than 0.5 µg·kg–1, deficiency is likely to occur for most
crops. However, toxicity may occur when boron levels
are greater than 5.0 µg·kg–1 [21]. The total amounts of
iron in surface and subsurface soils were 270.5 ± 1.8 and
265.1 ± 4.4 µg·kg–1, and the concentrations of manganese
were 4.8 ± 0.1 and 4.6 ± 0.1 µg·kg–1 respectively. There-
fore, small fraction from the total amount of micronutri-
ents is available to plants.
3.3. Sodium and Some Heavy Metals
The measured values of soluble, exchangeable, extract-
able, and available forms of sodium in surface and sub-
surface soil samples are given in Figure 3. Extractable so-
dium (139.4 mg·kg–1) represents the available form which
can be measured using ammonium acetate extraction me-
thod [14], while exchangeable sodium (83 mg·kg–1) was
calculated as the difference between the extractable and
the soluble forms. Total soil sodium was determined us-
ing the conventional ammonium acetate extraction method
Available subsurface
Figure 2. Soluble and available iron, manganese, copper,
and zinc in surface and subsurface soils measured by ICP-
AES in µg·kg–1.
Figure 3. Soluble, exchangeable, extractable and available
forms of sodium in sur face and subsurface soi l samples mea-
sured by flame photometer in mg·kg–1. Each value is the av-
erage for nine replicates.
Copyright © 2012 SciRes. OJSS
Analysis of Macro and Micronutrients in Soils from Palestine Using Ion Exchange Membrane Technology
Figure 4. Soluble and available forms of chromium in differ-
ent soil depths measured by ICP in µg·kg–1.
(Figure 3). However, this fraction can be determined more
accurately by IEM extraction method.
Interestingly, the availability of heavy metals was pre-
dicted by applying the IEM (Figure 4). Chromium was
detected in surface and subsurface soils.
4. Conclusion
IEM method allowed a single extraction and a single sub-
sequent measurement of the concentrations of the avail-
able forms of the different macro- and micro-nutrients.
The assessment of plant available nutritional ions using
IEM may be superior to the standard chemical extractions.
The exchangeable quantity of nutrients, which can rela-
tively easily mobilized or mineralized during the growing
season, is included in IEM extraction. This leads to better
evaluation of the exactly amount of the fertilizer needed
for the growing crops. There are no significant differen-
ces between available potassium and sodium measured
by IEM or that measured by the conventional ammonium
acetate extraction. The available amounts of different ions
in standard soil sample were measured using IEM extrac-
tion method, and the results are in good agreement with
that measured by the conventional methods.
5. Acknowledgements
The authors thank Prof. Mustafa Khamis and Prof. Magdy
el-Dakiky for their suggestions and helpful discussions.
Authors also thank the staff of the Center for the Chemi-
cal and Biological Research in Al-Quds University for
their technical assistance. Special thanks are due to Mr.
Azmi Saleh, Palestine Technical University (PTUK) for
his constructive and objective comments on the manu-
[1] A. S. Ayoub, B. A. McGaw, C. A. Shand and A. J. Mid-
wood, “Phytoavailability of Cd and Zn in Soil Estimated
by Stableisotope Exchange and Chemical Extraction,” Plant
and Soil, Vol. 252, No. 2, 2003, pp. 291-300.
[2] N. C. Brady, “The Nature and Properties of Soils,” Mac-
millan Publishing Company, New York, 1990.
[3] P. H. Raven, R. B. Linda and B. J. George, “Environment,”
Saunders College Publishing, Orlando, 1995.
[4] E. O. McLean and M. E. Watson, “Soil Measurements of
Plant-Available Potassium,” In: R. D. Munson, Ed., Po-
tassium in Agriculture, Soil Science Society of America,
Madison, 1985, pp. 227-308.
[5] R. Durand, N. Bellon and B. Jaillard, “Determining the
Net Flux of Charge Released by Maize Roots by Directly
Measuring Variations of the Alkalinity in the Nutrient So-
lution,” Plant and Soil, Vol. 229, No. 2, 2001, pp. 305-318.
[6] M. J. McLaughlin, P. A. Lancaster, P. W. G. Sale, N. C.
Uren and K. I. Peverill, “Use of Cation/Anion Exchange
Membranes for Multi-Element Testing of Acidic Soils,”
Plant and Soil, Vol. 155-156, No. 1, 1993, pp. 223-226.
[7] K. J Greer and J. J. Schoenau, “A Rapid Method for As-
sessing Sodicity Hazard Using a Cation Exchange Mem-
brane,” Soil Technology, Vol. 8, No. 4, 1996, pp. 287-292.
[8] R. R. Schnabel, “Nitrate and Phosphate Recovery from
Anion Exchange Resins,” Communications in Soil Science
and Plant Analysis, Vol. 26, No. 3-4, 1995, pp. 531-540.
[9] P. Qian, J. J. Schoenau and W. Z. Huang, “Use of Ion
Exchange Membranes in Routine Soil Testing,” Commu-
nications in Soil Science and Plant Analysis, Vol. 23, No.
15-16, 1992, pp. 1791-1804.
[10] S. Sato and N. B. Comerford, “Assessing Methods for
Developing Phosphorous Desorption Isotherms from Soils
Using Anion Exchange Membranes,” Plant and Soil, Vol.
279, No. 1-2, 2006, pp. 107-117.
[11] M. B. Turrion, J. F. Gallardo and M. I. Gonzalez, “Ex-
traction of Soil-Available Phosphate, Nitrate, and Sul-
phate Ions Using Ion Exchange Menbranes and Determi-
nation by Ion Exchange Chromatography,” Communica-
tions in Soil Science and Plant Analysis, Vol. 30, No. 7-8,
1999, pp.1137-1152.
[12] T. Pare, E. G. Gregorich and B. H. Ellert, “Comparison of
Soil Nitrate Extracted by Potassium Chloride and Adsorbed
on an Anion Exchange Membrane in Situ,” Communica-
tions in Soil Science and Plant Analysis, Vol. 26, No. 5-6,
1995, pp. 883-898. doi:10.1080/00103629509369341
[13] Applied Research Institute-Jerusalem, “Environmental Pro-
file for the West Bank Volume 2: Jericho District,” Ap-
plied Research Institute-Jerusalem, Bethlehem, 1995.
[14] L. A. Richards, “Diagnosis and Improvement of Saline
and Alkali Soils,” U.S. Government Printing Office, Wash-
ington DC, 1954.
[15] J. F. van Staden and R. E. Taljaard, “Determination of
Ammonia in Water and Industrial Effluent Streams with
Copyright © 2012 SciRes. OJSS
Analysis of Macro and Micronutrients in Soils from Palestine Using Ion Exchange Membrane Technology
Copyright © 2012 SciRes. OJSS
the Indophenol Blue Method Using Sequential Injection
Analysis,” Analytica Chimica Acta, Vol. 344, No. 3, 1997,
pp. 281-289. doi:10.1016/S0003-2670(96)00523-5
[16] E. Ballesteros, A. Rios and M. Valcárcel, “Integrated Auto-
matic Determination of Nitrate, Ammonium and Organic
Carbon in Soil Samples,” Analyst, Vol. 122, No. 4, 1997,
pp. 309-313. doi:10.1039/A607849D
[17] F. Zhang, J. Niu, W. Zhang, X. Chen, C. Li, L. Yuan and
J. Xie, “Potassium Nutrition of Crops under Varied Re-
gimes of Nitrogen Supply,” Plant Soil, Vol. 335. No. 1-2,
2010, pp. 21-34. doi:10.1007/s11104-010-0323-4
[18] P. Mäser, M. Gierth and J. I. Schroeder, “Molecular Mecha-
nisms of Potassium and Sodium Uptake in Plants,” Plant
and Soil, Vol. 247, No. 1, 2002, pp. 43-54.
[19] R. Setia, K. N. Sharma, P. Marschner and H. Singh,
“Changes in Nitrogen, Phosphorous, and Potassium in a
Long-Term Continuous Maize-Wheat Cropping System in
India,” Communications in Soil Science and Plant Analy-
sis, Vol. 40, No. 21-22, 2009, pp. 3348-3366.
[20] Q. Zeng and P. Brown, “Soil Potassium Mobility and Up-
take by Corn under Differential Soil Moisture Regimes,”
Plant and Soil, Vol. 221, No. 2, 2000, pp. 121-134.
[21] J. Ryan, S. Garabet, K. Harmsen and A. Rashid, “A Soil
and Plant Analysis Manual Adapted for the West Asia
and North Africa Region,” International Center for Agri-
cultural Research in the Dry Areas, Aleppo, 1996.
[22] J.-L. Zhang, T. J. Flowers and S.-M. Wang, “Mechanisms
of Sodium Uptake by Roots of Higher Plants,” Plant Soil,
Vol. 326, No. 1-2, 2010, pp. 45-60.
[23] M. Giese, Y. Z. Gao, S. Lin and H. Brueck, “Nitrogen
Availability in a Grazed Semi-Arid Grassland Is Domi-
nated by Seasonal Rainfall,” Plant and Soil, Vol. 340, No.
1-2, 2010, pp.157-167. doi:10.1007/s11104-010-0509-9
[24] Z.-Y. Yuan and L.-H. Li, “Soil Water Status Influences
Plant Nitrogen Use: A Case Study,” Plant Soil, Vol. 301,
No. 1-2, 2007, pp. 303-313.
[25] B. van Raij, J. A. Quaggio and N. M. da Silva, “Extrac-
tion of Phosphorus, Potassium, Calcium, and Magnesium
from Soils by an Ion-Exchange Resin Procedure,” Com-
munications in Soil Science and Plant Analysis, Vol. 17,
No. 5, 1986, pp. 547-566.
[26] S. M. Helali, H. Nebli, R. Kaddour, H. Mahmoudi, M. La-
chaal and Z. Ouerghi, “Influence of Nitrate—Ammonium
Ratio on Growth and Nutrition of Arabidopsis thaliana,”
Plant Soil, Vol. 336, No. 1-2, 2010, pp. 65-74.
[27] M. M. Wander, D. V. McCracken, L. M. Shuman, J. W.
Johnson and J. E. Box, “Anion-Exchange Membranes Used
to Assess Management Impacts on Soil Nitrate,” Com-
munications in Soil Science and Plant Analysis, Vol. 26,
No. 15-16, 1995, pp. 2383-2390.
[28] P. Nesse, J. Grava and P. R. Bloom, “Correlation of Sev-
eral Tests for Phosphorous with Resin Extractable Phos-
phorous for 30 Alkaline Soils,” Communications in Soil
Science and Plant Analysis, Vol. 19, No. 6, 1988, pp. 675-
[29] S. V. Karmarkar, “Quick Ion Chromatographic Determi-
nation of Sulfate Alone in Soil Extracts and Natural Wa-
ters,” Communications in Soil Science and Plant Analysis,
Vol. 27, No. 3-4, 1996, pp. 843-852.
[30] H. D. Foth, “Fundamentals of Soil Science,” John Wiley
& Sons, New York, 1978.
[31] R. J. Haynes, “Effects of Soil Acidification on the Chemi-
cal Extractability of Fe, Mn, Zn and Cu and the Growth
with Micronutrient Uptake of Highbush Blueberry Plants,”
Plant and Soil, Vol. 84, No. 2, 1985, pp. 201-212.