physicochemical properties of soil under different land ...to satisfy the food demand of growing...

INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 6, No 6, 2016

© Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0

Research article ISSN 0976 – 4402

Received on January 2016 Published on May 2016 941

Physicochemical properties of soil under different land use practices

located near Bhawanipatna town in Odisha, India Chandan Sahu, Sradhanjali Basti, Rudra Pratap Pradhan, Sanjat Kumar Sahu

P.G. Department of Environmental Sciences, Sambalpur University

[email protected]

doi:10.6088/ijes.6089

ABSTRACT

Soil physicochemical parameters provide basic assessing tool to study the soil health

condition and also forms the base for biological activity in soil. Soil quality is likely to be

disrupted during change in land use practices. Keeping this in view a work was undertaken to

determine the physicochemical properties of soil under different land use practices (viz.

forest land, pasture land, sugarcane field and rice field) located near Bhawanipatna town of

Odisha, India. The work was carried out in 3 seasons viz. pre monsoon, monsoon and post

monsoon during April 2013 to November 2013. The results of the physicochemical

parameters revealed high soil temperature in the pasture (37.830 C) and low soil temperature

in forest land (27.830 C). On the other hand the moisture content was high in the rice

(27.97%) and sugarcane field (20.68%) than that of forest (14.15%) and pasture land (8.67%).

The soil pH was found to be minimum (6.45) in rice field and maximum pH (8.10) in forest

land, whereas, the highest conductivity was measured in the pasture land (379.50µS/cm) and

the lowest conductivity was measured in the sugarcane field (76.1µS/cm). The organic carbon

and organic matter contents was in the order: forest land (2.73, 4.71%) > sugarcane field

(2.59, 4.47%) > rice field (2.43, 4.19%) > pasture land (1.08, 1.86%). However, the results

with the NPK assessment were variable and were in the following order in case of N: pasture

land (82 mg/kg) > sugarcane field (75.33 mg/kg) > rice field (55 mg/kg) > forest land (38.33

mg/kg), in case of P: rice field (99.83 mg/kg) > sugarcane field (88.33 mg/kg) > forest land

(59 mg/kg) > pasture land (51.67 mg/kg) and in case of K: forest land (0.141 mg/g) > pasture

land (0.134 mg/g) > rice field (0.086 mg/g) > sugarcane field (0.078 mg/g). The results,

however revealed an insignificant variation in physicochemical parameters indicating a very

little or no degradation in soil quality of man engineered agro-ecosystems (sugarcane field,

rice field and pasture land) as compared to natural ecosystem like forest land till today.

However, to check deterioration of soil quality in long run, proper soil management with

sustainable agricultural practices is urgently needed in the human interfered ecosystems.

Keywords: Land use, physicochemical properties, forest, pasture, sugarcane, rice field

1. Introduction

India is the second most populous country (130 crores as per 2011 census) in the world next

to China, where a large part of the population is dependent upon agriculture. The live stock

population of India also constitutes 1/6th of the world population. To satisfy the food demand

of growing human population and forage demand of huge livestock population, natural

forests are not only converted to pasture and agricultural fields, but agricultural fields are also

put under severe stress because of conventional method of agricultural practices which

ultimately results in the deterioration of soil health in converted ecosystems (Mishra et al.,

1979).

Physicochemical properties of soil under different land use practices located near Bhawanipatna town in

Odisha, India

Chandan Sahu et al.,

International Journal of Environmental Sciences Volume 6 No.6 2016 942

The physical, chemical and biological properties of the soil are intricately related with each

other. Soil physical and chemical properties are influenced by the microbiological mediation

process such as decomposition and mineralization of organic matter, nutrient cycling and soil

aggregate formation (Dick and Tabatabai, 1984) and in turn their activities are also regulated

through physicochemical properties of the soil (Aon and Colaneri, 2001) like soil texture,

temperature, moisture level, pH, organic matter content, cationic and anionic nutrients.

Results of this analysis provide valuable information on the capacity of the soil to supply

nutrients (Ladd and Jackson, 1982; Nannipieri et al., 1996) and sustain plant growth

(Nannipieri et al., 1996; James et al., 1991) and in turn in the diagnosis of the health of the

soil (McLaren, 1975; Frankenberger and Johanson, 1983). Therefore, measurement of soil

health under different land use systems is highly essential not only for protection of valuable

soil resources but also for their improvement through proper soil management practices.

Keeping this in view a comprehensive work was undertaken to measure the physicochemical

and biological properties of soil under different land use practices located near Bhawanipatna

town in Odisha, India. The biological properties of the soil assessed through carbon dioxide

evolution and enzyme activities has been reported elsewhere (Sahu and Sahu, 2016; per.

comm.). In the present work, the physicochemical properties of the soil under different land

use practices are reported here under.

2. Material and methods

2.1 Geographical location of study area

The study area belongs to the Sujanpur village near headquarter town of Bhawanipatna in the

district of Kalahandi, Odisha. The study involves 4 land use systems viz. pasture land site

(19o54’28.89” N, 83o11’33.83” E) which is 2 km away from the Bhawanipatna town towards

Sujanpur village, whereas, the rest three sites viz. sugarcane field (19o54’27.10” N,

83o12’50.24” E), rice field (19o54’27.23” N, 83o12’52.16” E) and forest land (19o54’28.52”

N, 83o12’50.04” E) is in the village area of Sujanpur which is 5 km away from Bhawanipatna

town.

2.2 Sampling and analysis of soil

The sampling was done thrice during the year 2013 i.e. during Pre-monsoon (April),

Monsoon (August) and Post-monsoon (November). The soil samples were taken using a soil

core sampler at 0-10 cm depth in 5 different locations (replicas) from each field (land use) by

random sampling method in each season. Temperature of the soil was recorded on the spot.

The soil samples were transported to the laboratory immediately in air-tight zip lock bags

keeping inside the ice bucket. The samples were air dried and sieved through 2mm sieve

before use for physicochemical analysis excepting soil moisture which was analyzed by the

oven dry method expressed in %. The other physicochemical parameters like pH,

conductivity, organic carbon and organic matter, sodium, potassium, nitrate and phosphate

were analyzed as per the standard methods the pH and electrical conductivity was measured

by glass electrode using soil : double distilled water in a ratio of 1 : 5 (w/v). Organic carbon

and organic matter was analyzed according to Walkley and Black’s (1934) rapid oxidation

procedure. The nitrate content was estimated by phenol disulphonic acid method (Davis,

1916). Phosphate content was determined spectrophotometrically by the molybdenum blue


Odisha, India



method (Hesse, 1971) using H2SO4 as an extractant. The sodium and potassium content was

determined flame photometrically following the method of Hanways and Heidel (1952).

3. Result and Discussion

Table – 1 shows the range and mean values for different soil parameters in various land use

practices. Soil temperature and soil moisture nourishes the condition for biological activity in

soil. A proper blend in the two parameters can actually prove to be more fruitful to the soil

health condition. The soil temperature ranged from 35 – 400 C in pre-monsoon, 24 – 38.50 C

in monsoon and 24.5 – 35 0C in post-monsoon irrespective of the land use type (Fig. 1). The

average temperature of soil recorded in forest, pasture, sugarcane and rice field was 27.83,

37.83, 30.83 and 33.0 0C respectively (Table -1). High level of soil temperature determined in

the pasture land may be attributed to bare exposure of the soil to the sunlight, whereas, low

level of soil temperature recorded in forest land may be attributed to interception of canopy to

sunlight. The soil moisture content in different land use systems ranged from 1.51 – 25.39%

during pre-monsoon, 12.08 – 32.72% during monsoon and 12.41 – 25.79% during post-

monsoon (Fig. 2). The average value of soil moisture was 14.15% in forest land, where as in

pasture, sugarcane and rice field it was 8.67, 20.68 and 27.97% respectively (Table -1). The

present study indicates high moisture content in the rice and sugarcane field than the forest

and pasture land. This is because of the fact that mulching was a common practice in

cultivated fields.

The pH of the soils under different land use systems were in the range of 6.45 – 8.10 in the

pre-monsoon, 6.60 – 6.97 in the monsoon and 6.79 – 7.87 in the post-monsoon (Fig. 3). The

soil pH was found to be minimum (6.45) in rice field and maximum pH (8.10) in forest land

irrespective of the seasons with average being 7.16, 7.60, 6.93 and 6.96 in forest, pasture,

sugarcane and rice field respectively (Table -1). The reason for slightly low pH in cultivated

lands might be due to the application of acidic fertilizers in the soil. The present findings

deviate from the results reported by Kizilkaya and Dengiz (2010) who opined that the pH of

agricultural lands is in the alkaline range.

Soil conductivity in different land use systems found to be highest in monsoon season

(250.80 – 379.50 µS/cm) followed by post-monsoon (206.20 – 218.80 µS/cm) and pre-

monsoon (76.16 – 135.20 µS/cm) as shown in Fig. 4. The highest conductivity was measured

in the pasture land (379.50µS/cm) and the lowest conductivity was measured in the sugarcane

field (76.1µS/cm). The average value of conductivity was 221.43, 237.97, 188.55 and 196.87

µS/cm in forest, pasture, sugarcane and rice field respectively (Table -1). Similar results have

also been reported by Acosta – Martinez et al. (2007), who highlighted the addition of

manure due to grazing activities by the remnants, might be the factor for increasing the ionic

activity in the pasture land.

The range of organic carbon and organic matter in different land use practices was 0.54 –

4.20 and 0.93 – 7.24% respectively in pre-monsoon, while in the monsoon and post-monsoon

it was 1.68 – 3.93 and 2.90 – 6.78%, and 0.66 – 1.92 and 1.14 – 3.31% respectively (Fig. 5 &

6 respectively). The maximum OC and OM content was recorded in forest land (4.20% and

7.24% respectively) and the minimum was recorded in the pasture land (0.54% and 0.93%

respectively). The high level for organic matter obtained in the natural forest may be

attributed to the large contribution of litter (Burns, 1986) and the lowest value obtained in

pasture land, may be attributed to constant grazing by the livestock (Nannipieri et al., 1980)

and rapid oxidation of oxidisable organic matter at high temperature (as evident from soil


Odisha, India



temperature measurement). Soil organic carbon and organic matter content also found to be

decreased with the change in land use practice from natural forest to cultivated land, but the

cultivated land showed higher OC and OM content as compared to the pasture land. This

might be due to the contribution of crop residues after the harvest in the agricultural fields.

Kizilkaya and Dengiz (2010) in their study also highlighted the decrease in OC content in

agricultural soil as compared to the natural forest.

Nitrate content, irrespective of land use types, was found to be highest in the monsoon (61 –

163 mg/kg), followed by post monsoon (40 – 76 mg/kg) and pre-monsoon (14 – 32 mg/kg)

and highest concentration of nitrate was measured in the pasture land (163mg/kg) and the

lowest concentration was measured in the forest land (14 mg/kg) during the period of study

(Fig. 9). Similarly, the phosphate content was found to be highest in the monsoon (82.5 – 190

mg/kg), followed by post monsoon (38.5 – 100 mg/kg) and pre-monsoon (27.5 – 55 mg/kg).

But the maximum concentration of phosphate was found in rice field (190 mg/kg) and the

minimum concentration was in forest land (27.50 mg/kg) during the period of study. The

average value of nitrate and phosphate was 38.33 and 59, 82 and 51.67, 75.33 and 88.33, and

55 and 99.83 mg/kg in forest, pasture, sugarcane and rice field respectively. It is evident from

the data that in pasture and /or cultivated land the nitrate and phosphate content was higher

than that of their counterparts in natural forest. This might have been due to the (i)

application of chemical fertilizers in the sugarcane and rice fields during cultivation (Skujins,

1978) and (ii) deposition of fecal materials by grazing animals in pasture lands (Skujins, 1978

and Acosta – Martinez et al., 2007).

Potassium content of soil varied from 0.032 – 0.099 mg/g during the pre-monsoon, 0.145 –

0.203 mg/g during the monsoon and 0.037 – 0.120 mg/g during post-monsoon in different

land use systems. Maximum concentration of potassium was noted in the forest land (0.203

mg/g) and the minimum concentration was noted in sugarcane field (0.032 mg/g) (Fig. 8).

The decline in the potassium content in the agricultural fields might have been due to large

uptake of this major nutrient by the rice and sugarcane crops (Mishra et al., 1979;Cleveland

et al., 2003).

Sodium is not a plant nutrient; however, it is required by the plants in a very low quantity.

High sodium content decreases the soil quality and ultimately decreases the plant production

(Bymes and Amberger, 1989). Very often, an increase in sodium concentration declines the

availability of other ions like Ca, Mg, K etc to plants. Sodium content ranged from 0.005 –

0.007 mg/g during the pre-monsoon, 0.031 – 0.034 mg/g during the monsoon and 0.008 –

0.031 mg/g during the post-monsoon. Highest concentration of sodium was found in rice

field (0.035 mg/g) and the minimum concentration was found in forest land (0.005 mg/g)

with average being 0.023, 0.015, 0.017 and 0.017 mg/g in forest, pasture, sugarcane and rice

field respectively (Fig. 7). In the present study, all the soils were found to contain low level of

sodium.

However, when the data for each parameter was subjected to two-way ANOVA to see

whether significant difference exist with respect to different land use and seasons at 0.05

confidence limit (Table – 2), soil moisture, soil temperature and potassium content showed

significant variation with respect to both land use and seasons (F1 ≥ 4.76, F2 ≥ 5.14, p < 0.05),

and conductivity, sodium, nitrate and phosphate content showed significant variation with

respect to seasons only (F2 ≥ 5.14, p < 0.05). But soil pH, organic carbon and organic matter


Odisha, India



did not show any significant variation with respect to both land use and seasons (F1 ≤ 4.76, F2

≤ 5.14, p > 0.05).

A correlation matrix among different parameters of various land use systems was also

worked out and given in Table 3. The value of “r” marked with an asterik (*) represents

strong positive or negative correlation at 0.05 level of significance. Conductivity showed

positive correlation with soil pH and potassium content of soil (r ≥ 0.815, p < 0.05), while

soil moisture showed positive correlation with phosphate content of soil (r ≥ 0.815, p < 0.05).

The following parameters showed negative correlation: soil pH with organic carbon, organic

matter, moisture and phosphate (r ≥ -0.815, p < 0.05); conductivity with moisture and

phosphate (r ≥ -0.815, p < 0.05); temperature with sodium, organic carbon and organic matter

(r ≥ -0.815, p < 0.05); moisture with potassium (r ≥ -0.815, p < 0.05); sodium with nitrate (r ≥

-0.815, p < 0.05) and potassium with phosphate (r ≥ -0.815, p < 0.05).

Figure 1: Seasonal variation in soil temp (0C) in different land use system during 2013

Figure 2: Seasonal variation in soil moisture (%) in different land use system during 2013


Odisha, India



Figure 3: Seasonal variation in soil pH in different land use system during 2013

Figure 4: Seasonal variation in soil conductivity (µs/cm) in different land use system during

2013

Figure 5: Seasonal variation in soil orgonic carbon % in different land use system during

2013


Odisha, India



Figure 6: Seasonal variation in soil orgonic matter % in different land use system during

2013

Figure 7: Seasonal variation in nitrate concentration (mg/kg) of soil in different land use

system during 2013

Figure 8: Seasonal variation in phosphate concentration (mg/kg) of soil in different land use

system during 2013


Odisha, India



Figure 9: Seasonal variation in potassium concentration (mg/kg) of soil in different land use

system during 2013

Figure 10: Seasonal variation in sodium concentration (mg/kg) of soil in different land use

system during 2013


Odisha, India



Table 1: Range and Mean ± SD values for different parameters in various land use practices

Sugracane Rice Forest Pasture

Range

Mean ±

SD Range

Mean ±

SD Range

Mean ±

SD Range

Mean ±

SD

Soil

Temperature

(0 C)

28 -

36.5

30.83 ±

4.01

29 -

40

33.00 ±

4.97

24 –

35

27.83 ±

5.07 35 - 40

37.83 ±

2.09

Soil

Moisture

(%)

13.08

-

25.27

20.68 ±

5.41

25.39

-

32.72

27.97 ±

3.37

8.73 -

16.99

14.15 ±

3.84

1.51 -

12.41

8.67 ±

5.06

Soil pH 6.6 -

7.55

6.93 ± 0.44

6.45 -

7.79

6.96 ±

0.59

6.62 -

8.1

7.17 ±

0.66

6.97 -

7.96

7.6 ±

0.45

Soil

Conductivity

(µS/cm)

76.16

-

270.7

188.55

± 82.25

103.5

-

250.8

196.87

± 66.29

135.2

-

266.2

221.43

± 60.99

128.2 -

379.5

237.97

±

105.02

Organic

Carbon (%)

1.920

-

3.930

2.59 ±

0.95

1.380

-

3.510

2.43 ±

0.87

0.660

-

4.200

2.73 ±

1.51

0.540 -

1.680

1.08 ±

0.47

Organic

Matter (%)

3.310

-

6.775

4.47 ±

1.63

2.379

-

6.051

4.19 ±

1.50

1.138

-

7.241

4.71 ±

2.60

0.931 -

2.896

1.86 ±

0.81

Nitrate

(mg/kg)

32 -

118

75.33 ±

35.11

31 -

83

55.00 ±

21.42

14 -

61

38.33 ±

19.22

24 -

163

82.00 ±

59.03

Phosphate

(mg/kg)

55 -

110

88.33 ±

23.92

52 -

190

99.83 ±

63.80

27.5 -

92

59.00 ±

26.35

34 -

82.5

51.67 ±

21.88

Potassium

(mg/g)

0.032

-

0.164

0.078 ±

0.061

0.051

-

0.145

0.086 ±

0.042

0.099

-

0.203

0.141 ±

0.045

0.092 -

0.194

0.134 ±

0.044

Sodium

(mg/g)

0.006

-

0.031

0.017 ±

0.010

0.006

-

0.035

0.017 ±

0.013

0.005

-

0.034

0.023 ±

0.013

0.007 -

0.032

0.015 ±

0.011


Odisha, India



Table 2: Two-way ANOVA for different parameters between various land use practices and

seasons

Parameters Source of

Variation SS df MS FCal

Ftab at

0.05

S or

NS

Soil

Temperature

Between Land

use 159.56 3 53.19 10.46 4.76 S

Between

Seasons 182.00 2 91.00 17.90 5.14 S

Soil Moisture

Between Land

use 625.12 3 208.37 31.39 4.76 S

Between

Seasons 203.12 2 101.56 15.30 5.14 S

Soil pH

Between Land

use 0.86 3 0.29 0.79 4.76 NS

Between

Seasons 1.36 2 0.68 1.86 5.14 NS

Soil

Conductivity

Between Land

use 4618.47 3 1539.49 0.94 4.76 NS

Between

Seasons 67910.29 2 33955.14 20.76 5.14 S

Organic

Carbon

Between Land

use 5.22 3 1.74 1.92 4.76 NS

Between

Seasons 6.99 2 3.50 3.87 5.14 NS

Organic

Matter

Between Land

use 15.52 3 5.17 1.92 4.76 NS

Between

Seasons 20.79 2 10.40 3.87 5.14 NS

Nitrate

Between Land

use 3555.33 3 1185.11 2.16 4.76 NS

Between

Seasons 13350.17 2 6675.08 12.18 5.14 S

Phosphate

Between Land

use 4783.73 3 1594.58 1.92 4.76 NS

Between

Seasons 12475.17 2 6237.58 7.53 5.14 S

Potassium

Between Land

use 0.01 3 0.00 21.15 4.76 S

Between

Seasons 0.03 2 0.01 93.46 5.14 S

Sodium

Between Land

use 0.0001 3 0.0000 0.89 4.76 NS

Between

Seasons 0.0015 2 0.0007 19.78 5.14 S


Odisha, India



Table 3: Correlation matrix among different parameters in various land use practices

pH EC OC OM Moist. Temp. Na K NO3

- PO4-

pH 1.000

EC 0.950* 1.000

OC -

0.881* -0.709 1.000

OM -

0.881* -0.709 1.000 1.000

Moist. -

0.876*

-

0.870* 0.617 0.617 1.000

Temp. 0.660 0.439 -

0.933*

-

0.933* -0.298 1.000

Na -0.245 0.054 0.666 0.666 -0.040 -

0.854* 1.000

K 0.768 0.923* -0.385 -0.385 -

0.822* 0.062 0.431 1.000

NO3- 0.374 0.068 -0.691 -0.691 -0.260 0.764

-

0.911* -0.270 1.000

PO4-

-

0.865*

-

0.923* 0.542 0.542 0.975* -0.205 -0.204

-

0.926*

-

0.061 1.000

‘*’ p < 0.05

3. Conclusion

It is an established fact that when the natural forest gets converted to pasture land and/or

subsequently to cultivable land, the soil quality and soil health is likely to diminish. But our

results did not show any significant difference with respect to physicochemical parameters

studied in different land use systems. This indicates that the soil quality has degraded to a

very little or no extent so far in human interfered ecosystems. However, proper soil

management with sustainable agricultural practices is urgently needed in the human

interfered ecosystems (pasture, sugarcane and rice field) located near Bhawanipatna town of

Odisha, India not only to check further deterioration of soil quality but also to restore the

health of the soil.

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