Distribution and Availability of Sulphur in some Terai Soils under Subtropical Zone of Eastern India
Table 2. Distribution of available sulphur (mg kg -1 ) in soils according to locations from where samples were collected
Available S (mg kg -1 )
Percent soil samples following in the category
Soil series/
Number of
content
Sl.
No.
benchmark
samples in each
sites
site
Low (<10 mg Medium (10-20 mg
Range
Mean
High (>20 mg kg -1 )
kg -1 )
kg -1 )
Coochbehar district
1
Lotafela
10
16.62-26.77
21.66
0
40.0 (4)*
60.0 (6)
2
Balorampur
10
17.29-36.50
21.88
0
60.0 (6)
40.0 (4)
3
Rajpur
10
15.35-22.96
19.52
0
60.0 (6)
40.0 (4)
4
Pundibari
10
18.75-30.37
23.83
0
10.0 (1)
90.0 (9)
5
Matiarkuthi
10
17.16-27.87
22.39
0
20.0 (2)
80.0 (8)
Jalpaiguri district
6
Berubari
10
21.46-31.43
25.54
0
0
100 (10)
7
Binnaguri
10
19.41-39.21
28.90
0
10.0 (1)
90.0 (9)
8
Mainaguri
10
16.61-30.16
23.70
0
20.0 (2)
80.0 (8)
9
Dhupguri
10
16.64-30.62
23.45
0
30.0 (3)
70.0 (7)
Darjeeling district
10
Kharibari
10
18.28-43.26
30.65
0
10.0 (1)
90.0 (9)
North Dinajpur district
11
Islampur
10
17.26-37.32
23.98
0
20.0 (2)
80.0 (8)
Overall figure
110
15.35 – 43.26
24.14
0
25.46 (28)
74.55 (82)
*figures in the parentheses represent the number of samples in each category of sulphur status in respective cases.
Results and Discussion
estimationȱofȱsilt+clayȱwhichȱaccountedȱforȱ22.72ȱtoȱ
52.72ȱwithȱaverageȱvalueȱofȱ36.31ȱperȱcent.ȱTheȱacidȱ
Physico-chemical characteristics of soil
ammoniumȱoxalateȱextractableȱAlȱ(ox-Al)ȱandȱFeȱ(ox-
Theȱresultsȱofȱsomeȱofȱtheȱimportantȱphysicochemicalȱ
Fe)ȱfractions,ȱobservedȱtoȱmaintainȱhighȱvariabilityȱ
characteristicsȱofȱsoilsȱstudiedȱareȱpresentedȱinȱTableȱ
inȱsoilsȱwhichȱrangedȱfromȱ0.01ȱtoȱ0.81ȱandȱ0.02ȱtoȱ
1.ȱ Aȱ perusalȱ ofȱ theȱ dataȱ showedȱ thatȱ soilsȱ variedȱ
0.76ȱwithȱmeanȱofȱ0.15ȱandȱ0.18ȱperȱcentȱrespectively.ȱ
widelyȱ inȱ theirȱ pHȱ valuesȱ rangingȱ betweenȱ 4.16ȱ
TheȱdithioniteȱextractableȱAlȱ(CBD-Al)ȱandȱFeȱ(CBD-
andȱ 6.50ȱ withȱ aȱ meanȱ valueȱ ofȱ 5.28.ȱ Theȱ organicȱ
Fe)ȱ fractionsȱ alsoȱ recordedȱ toȱ haveȱ highȱ extentȱ ofȱ
carbonȱ contentȱ ofȱ soilsȱ alsoȱ variedȱ widelyȱ rangingȱ
variabilityȱinȱtheirȱcontentsȱwithinȱtheȱlimitsȱofȱ0.02ȱ
fromȱ0.40ȱtoȱ2.42ȱwithȱanȱaverageȱofȱ1.13ȱperȱcent.ȱ
toȱ1.16ȱandȱ0.04ȱtoȱ0.81ȱwithȱrespectiveȱmeansȱofȱ0.21ȱ
CECȱofȱallȱtheȱsamplesȱstudiedȱandȱrecordedȱtheirȱ
andȱ0.27ȱperȱcent.ȱCombinedȱvalueȱofȱCBD-Alȱandȱ
valuesȱinȱbetweenȱ3.65ȱtoȱ12.58ȱwithȱaȱmeanȱofȱ7.56ȱ
CBD-Feȱalsoȱhasȱshownȱtoȱvaryȱwidelyȱbetweenȱ0.06ȱ
cmol(p + )kg -1 ȱsoil.ȱInȱrespectȱofȱtexture,ȱsoilsȱshowedȱ
andȱ2.13ȱwithȱitsȱmeanȱofȱ0.48ȱperȱcent.
markedȱ variationȱ inȱ theirȱ clayȱ contentȱ rangingȱ
fromȱ10.60ȱtoȱ23.96ȱwithȱhavingȱaȱmeanȱofȱ15.43ȱperȱ
Available sulphur
cent,ȱindicatingȱthatȱsoils,ȱinȱgeneral,ȱareȱcoarseȱinȱ Theȱ availableȱ Sȱ ofȱ experimentalȱ soilsȱ registeredȱ aȱ
texture.ȱSimilarȱwasȱtheȱresultȱinȱrespectȱofȱcombinedȱ highȱ variationȱ inȱ itsȱ contentȱ rangingȱ fromȱ 15.35ȱ toȱ
349