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The Pharma Innovation Journal 2021; 10(8): 665-670
ISSN (E): 2277- 7695
ISSN (P): 2349-8242
NAAS Rating: 5.23
TPI 2021; 10(8): 665-670
© 2021 TPI
www.thepharmajournal.com
Received: 18-06-2021
Accepted: 23-07-2021
Sri likhitha Gudla
Department of Soil Science &
Agriculture Chemistry, Sam
Higginbottom Institute of
Agriculture, Technology &
Sciences, Prayagraj, Uttara
Pradesh, India
Narendra Swaroop
Department of Soil Science &
Agriculture Chemistry, Sam
Higginbottom Institute of
Agriculture, Technology &
Sciences, Prayagraj, Uttara
Pradesh, India
Tarence Thomas
Department of Soil Science &
Agriculture Chemistry, Sam
Higginbottom Institute of
Agriculture, Technology &
Sciences, Prayagraj, Uttara
Pradesh, India
Akshita Barthwal
Department of Soil Science &
Agriculture Chemistry, Sam
Higginbottom Institute of
Agriculture, Technology &
Sciences, Prayagraj, Uttara
Pradesh, India
Corresponding Author:
Sri likhitha Gudla
Department of Soil Science &
Agriculture Chemistry, Sam
Higginbottom Institute of
Agriculture, Technology &
Sciences, Prayagraj, Uttara
Pradesh, India
Assessment of physico-chemical properties of black
cotton soils from different blocks of Guntur District,
Andhra Pradesh, India
Sri likhitha Gudla, Narendra Swaroop, Tarence Thomas and Akshita Barthwal
Abstract
The present investigation was carried at Sam Higginbottom University of Agriculture Technology and
Sciences to assess the Physicochemical properties of black cotton soils from different blocks of Guntur
district, Andhra Pradesh, India. A total of twenty-seven soil samples were collected randomly from
different depths, i.e., 0-15cm,15-30 cm, and 30-45cm. The study area consists of mostly black cotton
soil. These soils were moderate to strongly alkaline in reaction and non-saline. On the soil complex, the
dominant cation is calcium. The overall fertility status of the soils was low, medium, and high in
nitrogen, phosphorus, and potassium respectively. The calcium and magnesium ranges are high in these
clay soils. The sulfur is sufficient in these clay soils. As the soils were calcareous and strongly alkaline,
there is a need for the application of any acid-forming amendment (S containing amendments) and
organic materials to alleviate the nutrient deficiency and improve productivity.
Keywords: Physico-chemical properties, Alkaline, Water retaining capacity, Black cotton soils
1. Introduction
Soil is the backbone of our food security. Without healthy soils, farmers wouldn’t be able to
provide us with feed, fiber, food, and fuel. Our farmers need to understand the components
which make up the soil in which their crops grow. Adequate crop growth and its production
mainly depend on the appropriate nutrition, if there is a nutrient deficiency in the soil it affects
the growth rate of plants.
Nitrogen occupies the first position in the plant requirement among the nutrient elements,
followed by phosphorus and potassium (Samuel and Ebenezer, 2014; Solanki and Chavda,
2012)
[19, 24]
; Potassium is a major nutrient that plays a major role in different physiological
processes of plants helping plants to resist against diseases and improving physical
characteristics of the plant. Magnesium is necessary for the synthesis of chlorophyll pigment
in green plants and its deficiency causes the loss of healthy green color of leaves (Mahajan and
Billore, 2014)
[13, 20]
. Calcium ion is the key element in reducing the soil salinity erosion
content and as well as phosphorous loss through flowage. Phosphorus is the most important
element because the growth of plants depends on the availability of Phosphorous content in the
soils. Soil fertility and nutrient management are important factors that have a direct impact on
crop yield and quality.
To identify the fertility status of the selected area, various soil samples were collected from
pre-determined locations and were analyzed for Physico-chemical properties (pH and electrical
conductivity) chemical characteristics including fertility parameters like available nitrogen,
phosphorous, potassium, sulfur, and exchangeable basic cations constituting calcium,
magnesium.
2. Materials and Methods
2.1 Study area
The location of the Guntur district lies between 16
0
30
’
67” N latitude and 80
0
43'65" E
longitude. It covers a geographical area of 11,391 sq km. (Fig.1). The Krishna River forms the
northeastern and eastern boundary of the district, separating Guntur District from Krishna
District. It is located near the Bay of Bengal and is surrounded by many suburban areas.
Guntur district experiences a tropical climate in summer. And the dry and cold climate in
winter. The maximum temperature is 32
0
C and the minimum temperature is 20
0
C. The
average annual temperature is 28.5
o
C.
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When compared with winter, the summers have much more
rainfall. In a year, the average rainfall recorded is 906 mm.
2.2 Sample collection
Soil samples were collected from three different blocks of the
Guntur district of Andhra Pradesh. They are Pedakurapadu
Krosuru, Sattenpalli. Soil samples were collected with the
help of Khurpi, spade, and meter scale. In each block, three
villages were selected for sampling and were samples
collected randomly from different depths i.e., 0-15cm,15-
30cm, and 30-45cm. A total of twenty-seven soil samples
were collected.
Fig 1: Map of the study area
2.3 Soil analysis
The pH was determined in 1:2 soil water suspensions using
digital pH meter (Jackson, 1958). The EC was determined in
1:2 soil water suspensions using digital EC meter (Wilcox,
1950)
[30]
. The soil was distilled with alkaline potassium
permanganate as suggested by (Subbiah and Asija 1956)
[25]
and the ammonia evolved was determined. P in the soil
extract is determined colorimetrically using a Photoelectric
Colorimeter after developing molybdenum blue colour (Olsen
et al., 1954)
[18]
. The procedure was based on extraction with
1N NH4OAC (pH 7.0) and K was determined by Flame
Photometer (Toth and Prince, 1949)
[27]
. The same procedure
used for the estimation of K. Exchangeable calcium and
magnesium was determined by 1N Neutral Ammonium
Acetate Saturation Method or EDTA method as laid out by
Cheng and Bray (1951). Available sulphur was estimated by
the turbidimetric method as put forth by Bardsley and
Lancaster (1960)
[2]
.
3. Results and Discussion
3.1 pH and EC (ds m
-1
)
Table 1. depicted the statistical accumulation on pH and EC
of various farmer's fields which was found to be significant
differences due to depth and site. The pH ranges from 8.01 to
8.79. The highest mean value is recorded 8.79 in B3V2 and
the least mean value 7.50 in B2V3. The EC ranges from 0.37
to 0.81 ds m
-1
. The highest mean value is recorded at 0.81 ds
m
-1
in B2V1 and the least mean value of 0.37 ds m
-1
in B3V2.
Higher values were recorded in deeper layers. A similar trend
was observed by Dhale and Jagdish Prasad, (2009)
[9]
in the
black soil of Jalna district, Maharashtra.
3.2 Organic carbon and organic matter
Table 2. depicted the statistical accumulation on Organic
Carbon and Organic matter of various farmer's fields which
was found to be significant differences due to depth and site.
The Organic carbon ranges from 0.35 to 0.70%. The highest
mean value is recorded 0.70% in B2V1 and the least mean
value 0.35% in B3V2. The OM ranges from 0.60 to 1.16%.
The highest mean value is recorded at 1.16 in B1V1 and the
least mean value 0.67% in B2V2. When depth-wise values
were considered, lower values were recorded in deeper layers.
Nayak et al. (2002) observed a similar organic carbon range
(0.11 to 0.82 percent) in black soils of the Indo- Gangetic
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plains of West Bengal.
3.3 Available Nitrogen, Phosphorus, and Potassium
Table 3. depicted the statistical accumulation of Nitrogen (kg
ha
-1
) and Potassium (kg ha
-1
) of various farmer's fields and
depths which were found to be significant differences due to
depth and site but phosphorus showed nonsignificance due to
depth and significance due to site. The N ranges from 168 to
277.66(kg ha
-1
). The highest mean value is recorded 277.66 in
B2V1 and the least mean value 168. Similar trends were
observed by Bharmbe et al. (1999)
[4]
in Vertisols of the
Majalgao canal command area. The Phosphorus ranges from
11 to 60.3(kg ha
-1
) 3. The highest mean value is recorded
60.33(kg ha
-1
) in B1V1 and the least mean value 11(kg ha
-1
)
in B3V1. Satish (2003)
[21]
and Varaprasad Rao et al. (2008)
[28]
reported medium availability of phosphorus in soils of
Chebrolu Mandal, Guntur district, and Ramachandrapuram
Mandal, Chittoor districts of Andhra Pradesh, respectively.
The Potassium ranges from 505 to 984.33(kg ha
-1
). The
highest mean value is recorded at 984.33 in B1V1 and the
least mean value 479(kg ha
-1
) in B2V3. Similar observations
of high potassium content were reported by Bandyopadhyay
et al. (2004)
[1]
and Dhale and Jagdishprasad (2009)
[9]
in
black soils of Maharashtra. The available Nitrogen,
Phosphorus, and Potassium content were high values at the
surface than in lower layers.
3.4 Exchangeable Calcium and Magnesium
Table 4. depicted the statistical accumulation of exchangeable
calcium [cmol (p+) kg
-1
] showed no significant difference was
found at depth and a significant difference was found at
villages. Very low values were recorded in all the sites. This
may be due to the leaching of calcium as hydrogen is added to
the soil by the decomposition of organic matter as well as due
to heavy rainfall. The highest mean value of 27.7 cmol (p+)
kg
-1
was recorded at B3V3. And the lowest mean value of
22.76 cmol (p+) kg
-1
was recorded at B3V2. Magnesium
showed No significant difference in both depth and site. Very
low values were recorded in all the sites. This may be due to
the leaching of magnesium as hydrogen is added to the soil by
the decomposition of organic matter as well as due to heavy
rainfall. The highest mean value of 9.9 cmol (p+) kg-1 was
recorded in B1V1. The maximum exchangeable magnesium
of 11.73 cmol (p+) kg-1 was recorded in B1V3 while the
minimum value was recorded as 6.4 cmol (p+) kg-1 in B3V3.
Similar results were observed by Naga Raju Kola and Babu
Rao Gudipudi (2020)
[16]
. Soil Chemistry of Erravagu Sub-
basin of Guntur District, Andhra Pradesh 2020
3.5 Available Sulphur
Table 5. depicted the available sulfur (ppm) in soils from
various villages and at different profile depths. A significant
difference was found. Medium values of available sulfur were
recorded in all the sites. The highest mean value was recorded
at B2V1 as 36.66 ppm. Low values may be attributed to the
leaching of sulfur. The available sulfur was found to decrease
with an increase in depth. The maximum available sulfur was
recorded in B2V1 which was 36.33 ppm. While the minimum
value was recorded in B3V1 as 9.33 ppm. Similar trends were
observed in Inceptisol of Chittoor district, Andhra Pradesh
(Basavaraju et al, 2005)
[3]
and (Varaprasad Rao et al. 2008)
[28]
.
3.6 Correlation Coefficient (R) Between Physicochemical
Properties of Black Cotton Soils of Guntur District,
Andhra Pradesh, India
The electrical conductivity showed the significant negative
correlation with pH (-0.71 @ CD P = 0.01). The available
nitrogen showed the significant positive correlation with EC
(0.711 @ CD = 0.01). The available nitrogen showed non-
significant and negative correlation with pH (-0.334). The
available Phosphorus showed the significant positive
correlation with% organic carbon (0.549 @ CD P = 0.05).
The available Potassium showed the positive correlation with
both% organic carbon (0.576 @ CD P = 0.05) and
Phosphorus (0.970 @ CD P = 0.01). The exchangeable
calcium showed the significant positive correlation with
available nitrogen (0.820 @ CD P = 0.01). The exchangeable
magnesium showed the significant positive correlation with
Phosphorus (0.764 @ CD P =0.01) and Potassium (0.716 @
CD P = 0.01). The available sulphur showed the positive
correlation with both available Nitrogen (0.801@ CD P =
0.01) and exchangeable Calcium (0.540 @ CD P = 0.05).
Table 1: Soil pH and Soil EC (dS m-1) at different depths (cm)
villages
pH
EC
0- 15cm
30- 45cm
0-15cm
15-30cm
30- 45cm
B1 V1
7.8
8.2
0.73
0.79
0.85
B1 V2
8.36
8.53
0.39
0.43
0.47
B1 V3
8.25
8.62
0.63
0.67
0.7
B2 V1
8.3
8.51
0.77
0.82
0.86
B2 V2
8.4
8.71
0.43
0.46
0.48
B2 V3
7.9
8.2
0.63
0.69
0.75
B3 V1
8.45
8.81
0.53
0.57
0.61
B3 V2
8.62
8.91
0.33
0.37
0.42
B3 V3
8.74
8.82
0.43
0.47
0.5
Range
7.8- 8.74
8.2- 8.91
0.33- 0.77
0.37- 0.79
0.43- 0.86
Mean
8.31
8.59
0.54
0.58
0.62
F- test
F- test
S.Ed. (±)
s
s
0.024704
S
s
0.054379
Table 2: Soil Organic carbon (%) and Soil Organic matter (%) at different depths (cm)
villages
Organic carbon (%)
Organic matter
0- 15cm
15-30cm
30- 45cm
0- 15cm
15- 30cm
30- 45cm
B1 V1
0.72
0.68
0.63
1.24
1.17
1.08
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B1 V2
0.5
0.49
0.45
0.86
0.84
0.77
B1 V3
0.47
0.39
0.38
0.81
0.67
0.65
B2 V1
0.39
0.35
0.32
0.67
0.6
0.55
B2 V2
0.48
0.45
0.42
0.82
0.77
0.72
B2 V3
0.46
0.42
0.39
0.79
0.72
0.67
B3 V1
0.45
0.41
0.38
0.77
0.7
0.65
B3 V2
0.56
0.54
0.52
0.96
0.93
0.89
B3 V3
0.51
0.48
0.39
0.87
0.82
0.67
Range
0.39- 0.72
0.35-0.68
0.32- 0.63
0.67- 1.24
0.60- 1.17
0.55- 1.08
Mean
0.50
0.46
0.44
0.86
0.80
0.73
F-test
S.Ed. (±)
F- test
S.Ed. (±)
s
0.02117
S
0.0365
s
0.031265
s
0.0539
Table 3: Available NPK (kg ha-1) at different depths (cm)
villages
Available Nitrogen (kg ha
-1
)
Available phosphorus (kg ha
-1
)
Available Potassium (kg ha
-1
)
0-15cm
15-30cm
30-45cm
0-15cm
15-30cm
30-45cm
0-15cm
15-30cm
30-45cm
B1 V1
238
225
217
63
60
58
996
987
970
B1 V2
201
189
175
53
51
67
932
927
918
B1 V3
220
212
207
48
47
45
900
893
887
B2 V1
289
275
269
17
17
15
604
597
593
B2 V2
238
233
225
19
18
16
585
578
565
B2 V3
207
201
193
18
17
14
503
497
479
B3 V1
204
193
182
13
11
9
513
507
495
B3 V2
180
169
157
17
15
13
617
659
647
B3 V3
209
197
183
23
21
19
653
647
635
Range
180-289
169-275
157-269
13 - 63
11-60
9-67
503-996
497-987
479-970
Mean
220.66
210.44
200.88
30.11
28.56
28.44
700.33
699.11
687.66
F-test
S.Ed. (±)
F-test
S.Ed. (±)
F-test
S.Ed. (±)
C.D.at 0.05%
S
5.710
NS
0.5379
s
4.0339
S
10.601
S
6.5735
s
62.599
Table 4: Exchangeable calcium and Magnesium [cmol (p+)kg-1]
villages
Exchangeable calcium [cmol (p+)kg-1
Exchangeable magnesium [cmol (p+)kg-1
0- 15cm
15- 30cm
30- 45cm
0- 15cm
15- 30cm
30-45cm
B1 V1
22.5
27.5
26
10.5
9.9
9.3
B1 V2
24.7
23.5
24.1
12.3
11.7
11.2
B1 V3
27.8
24.3
26.1
11.3
10.5
10.3
B2 V1
34.5
32.7
33.2
9.5
8.7
8.3
B2 V2
26.3
24.3
23.2
10.2
9.8
9.3
B2 V3
25.8
24
24.5
7.2
6.8
7.1
B3 V1
24.9
23.5
23.2
7.9
7.8
7.7
B3 V2
23.7
22.5
22.1
6.8
6.7
6.6
B3 V3
28.9
27.4
26.8
6.5
6.3
6.4
Range
23.7- 34.5
22.5- 32.7
22.1- 33.2
6.5- 12.3
6.3- 11.7
6.4-11.2
Mean
26.56
25.52
25.46
9.13
8.68
8.46
F-test
S.Ed. (±)
F-test
S.Ed. (±)
NS
0.3577
NS
0.1959
S
1.0605
NS
0.6306
Table 5: Available Sulphur (ppm)
villages
Available Sulfur (ppm)
0-15cm
15-30cm
30-45cm
B1 V1
29
25
23
B1 V2
26
24
21
B1 V3
25
22
19
B2 V1
39
37
33
B2 V2
37
34
31
B2 V3
30
27
23
B3 V1
12
9
7
B3 V2
18
15
12
B3 V3
21
19
9
Range
12-39
9-37
7-33
Mean
26.33
23.55
19.77
F-test
S.Ed. (±)
S
1.8997
S
2.9239
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Table 6: Correlation coefficient (r) between physicochemical properties of black cotton soils of Guntur district, Andhra Pradesh, India
pH
EC
%OC
N
P
K
Ca
Mg
S
pH
1
EC
-0.721**
1
%OC
-0.252
-0.061
1
N
-0.334
0.710**
-0.287
1
P
-0.431
0.190
0.549*
-0.004
1
K
-0.268
0.129
0.576*
-0.014
0.970**
1
Ca
-0.070
0.592*
-0.456
0.820**
-0.131
-0.090
1
Mg
-0.297
0.149
0.096
0.286
0.764**
0.716**
-0.007
1
S
-0.475
0.446
-0.165
0.801**
0.112
0.056
0.540*
0.407
1
* Significant at (0.05) 5% level; ** Significant at(0.01) 1% level.
EC= Electrical Conductivity, OC=Organic Carbon, N=Available Nitrogen, P=Available Phosphorus, K=Available Potassium, Ca=Exchangeable
Calcium, M= Exchangeable Magnesium, S= Available Sulphur.
4. Conclusion
It is concluded that the study area consists of black cotton
soil. These soils were moderate to strongly alkaline in
reaction and non-saline. On the soil complex, the dominant
cation is calcium. The overall fertility status of the soils was
low, medium, and high in nitrogen, phosphorus, and
potassium respectively. The calcium and magnesium ranges
are high and sulfur is sufficient in these clay soils. These
analyses may help the farmers to maintain proper nutrient
management and as the soils were calcareous and strongly
alkaline, there is a need for the application of any acid-
forming amendment (S containing amendments) and organic
materials to alleviate the nutrient deficiency and improve
productivity.
5. Acknowledgement
I am highly indebted to my advisor for his guidance and
constant supervision as well as for providing necessary
information regarding the study. I express a heartfelt thanks to
the authors and thank the Hon'ble Vice-Chancellor, HOD, and
Advisor, Department of Soil Science and Agricultural
Chemistry, Sam Higginbottom University of Agriculture,
Technology and Sciences, Prayagraj, U. P.
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