Photonirvachak
J. Indian Soc. Remote Sens. (March 2010) 38 : 143–151
RESEARCH ARTICLE
Land suitability Studies for Major Crops in Pavagada Taluk, Karnataka using Remote Sensing and GIS Techniques. A. Sathish
. K.V. Niranjana,
Received: 22.09.2009 / Accepted: 25.12.2009
Keywords Land evaluation . Land suitability . Geographic Information System.
. Analyses . Soil suitability analyses . Remote sensing
Abstract Pavagada taluk of Tumkur district in Karnataka is one of the most backward taluks receiving less than 500 mm annual rainfall. The maximum area of the taluk is under monocropping, reasons for the same were not documented well. The present study was carried out using remote sensing data along with field survey and laboratory analysis for assessing the potentials and limitations of soil.
A. Sathish1 ( ) . K.V. Niranjana2 1 Agricultural Research Station, Kathalagere, Davanagere District, University of Agricultural Sciences, Bangalore 560 065, Karnataka, India 2 NBSS & LUP, Regional Centre, Bangalore - 560024, India
e-mail:
[email protected]
Using the basic information on soil, climate and topography based on the matching exercise between the growth and production requirements of the crop, suitability of soils for groundnut, paddy and finger millet was assessed as per FAO land evaluation. The soil suitability maps were prepared using Arc GIS software. About 48 per cent of the total area was moderate to marginally suitable and 13 per cent of the area was not suitable for both groundnut and finger millet. Lowland areas covering 12 per cent of the area was highly suitable, 15 per cent was moderate to marginally suitable and 20 per cent was not suitable for paddy cultivation.
Introduction Land suitability evaluation is the process of determining potential of land for alternative uses. The Land suitability evaluation forms a pre- requisite for land use planning (Sys et al., 1991). Each plant species requires specific soil and climatic conditions
144
for its optimal growth. The present day agriculture demands more from the soil which is subjected to severe degradation through improper management practices and use of chemical fertilizers and pesticides. The ever increasing demands for increasing food grain production could be met through systematic survey of the soils, evaluating their potentials for wide range of land use options and formulating land use plans which were economically viable, socially acceptable and environmentally sound. The traditional methods of survey are time consuming, labour intensive and expensive to generate data. With the advent of remote sensing the database generation became fast, cost effective and reliable. Thus generated data is integrated in GIS to obtain different thematic information for using in land evaluation techniques. The basic resource survey provides data which is useful when interpreted properly to obtain the required information. This necessitated for the development of wide range of soil survey interpretations or land evaluation approaches along with the use of geographic information system. Pavagada Taluk of Karnataka is one of the chronic drought affected taluk where in most of the area is under single crop. The major crops of the taluk include groundnut, paddy and finger millet. The productivity of these crops are very low as compared to state level. The basic soil data and information on soil suitability of crops were lacking to take up proper planning in the taluk. Hence in the present investigation, potentials and limitations of soils were assessed using satellite data along with conventional field survey. The basic data on soils was then used for studying the land suitability for groundnut, paddy and finger millet crops using FAO approach in a GIS environment. The earlier system of land evaluation grades the land from suitable to unsuitable irrespective of type of land use and management. Such a system cannot provide the necessary information to the land user to make a choice between land use options. The FAO framework to the land evaluation was used in the present study to know the consequences of applying the specified management to a particular parcel of land so that a choice could be made from the alternatives.
J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151
Materials and methods Study area Pavagada taluk is situated in Tumkur district of Southern Karnataka, India. It is surrounded on all the sides by Anantapur district of Andhra Pradesh and is connected with Chitradurga district of Karnataka state at only one point by a narrow strip of land on the north-west. It is located between 120 36' 00" to 130 03’10" N latitude and 780 20’02" E Longitude covering an area of 1358 km2.
Data and methodology A base map with permanent land features like roads, river and tanks along with major drainage lines was prepared using Survey of India toposheets. It was overlaid on IRS 1C LISS III geocoded FCC (Fig. 1). Based on image characteristics and contour information physiographic units such as hills and ridges, isolated hillock, mounds, rolling lands (10-15%), undulating lands (5-10%), gently sloping lands (1-3%) and valleys (0-1%) were demarcated. The number of physiographic units and their frequency of occurrence were listed. Rapid traversing of the entire toposheet area was undertaken in order to check the physiographic delineations and correction of physiographic units was done wherever necessary. Considering the geographic distribution and frequency of occurrence of physiographic units in a toposheet area, transects were delineated in such a way that it should cut across at least three or more physiographic units. In each physiographic unit, profiles were studied depending upon slope element in order to establish relationship between physiography and soils. Based on profile characteristics such as depth, colour, texture, gravelliness, structure, soil analysis data (pH, EC, OC, CEC, base saturation) pedons were classified as per USDA Soil Taxonomy (Soil Survey Staff, 1996). In this way, all the profiles (49 profiles) were studied, classified and grouped into different soil series associations depending upon the above said characteristics. For each physiographic unit, soil
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J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151
Fig. 1 Land suitability for groundnut, Pavagada taluk, Tumukur district
composition was worked out, the final composition so arrived at for a given physiographic unit was checked at random (outside transect area) for the accuracy of soil composition and soils were classified up to soil series association level. The land suitability classification for major crops like groundnut, paddy and finger millet in Pavagada taluk was attempted based on the parametric approach of FAO (1976). The evaluation was done using several parameters, wherein every soil mapping unit was rated as per limitation technique using the criteria. Table 1, 2 and 3 shows criteria used in assessing soil suitability for groundnut, paddy and finger millet. The overall suitability of the soil was determined based on the degree and the number of limitations for a particular unit. The final soil suitability was based on the number and degree of limitations. The suitability classes were then used in Arc GIS software to generate land suitability maps and area statistics.
Results and discussion The representative soil profiles of each series were numbered as Ballasamudra series (S1), BelliBatlu (S2), Kodamadagu (S3), Kotibande (S4), Kilarlahalli (S5), Mangalawada (S6), Rappam (S7), Racharlu (S8), Shailapura (S9), Srirangapura (S10), Srirangapura Tanda (S11) and Thimmanaikanapete (S12) for discussion. The present method assess the suitability of land for major crops such as groundnut, paddy and finger millet on the basis of a matching exercise between the growth and production requirements of the crop and socio-economic condition of the land user. Based on the number and degree of limitation in the present study, the suitability classes viz., highly suitable (S1), moderately suitable (S2), marginally suitable (S3) and permanently not suitable classes (N2) were adopted to category the soils. The soil-site characteristics of different soils as shown in Table 4 form the basic data
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J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151
Table 1 Criteria used in assessing soil suitability for groundnut in Pavagada Taluk, Tumkur District. Sl N o.
So il site ch aracteris ti cs
1
Climate 0 Tem perature ( C) LG P (Days ) – Bun ch t ype -Sp read in g t ype
2 4-3 3 10 5-12 0 13 5-15 0
33-3 5 9 0-10 5 1 05-1 20
20 -2 2 <90 90-1 05
<20 <90
-
2
To po graph y (%)
0-1
1-3
3-10
1 0-15
>15
3
Tex tu ral class
Sandy lo am
Lo amy san d, Sand y clay lo am
Clay loam, San dy cl ay
Sandy , Cl ay , Silty clay
-
4
G rav el/stones v ol ume (%) Su rf ace Su bsu rface
0-15 1 5-3 5
1 5-3 5 3 5-5 0
35 -5 0 50 -7 5
5 0-75 >75
>75 -
No li mit atio n 0
Ran ge i n d eg ree of limitation s Sligh t M oderate Sev ere li mitatio n limitatio n limit ation 1 2 3
Very severe li mitatio n 4
5
So il dept h (cm )
>80
5 0-8 0
25 -5 0
1 5-25
<15
6
-1 CEC (C mol (+) Kg )
>16
1 0-1 6
5-10
<5
-
7
Bas e satu ration (%)
>80
5 0-8 0
35 -5 0
<35
-
8
D rai nag e class
Well drai ned (D 5)
Mo derately well d rained (D 4)
Imperfectly d rained (D3 )
Po or / so me what excess iv ely d rain ed (D2 /D6 )
9
Su rf ace cru stin g
No ne
Sligh t
M oderate
Sev ere
Very p oo r / excess iv ely drain ed (D2 /D7 ) Very severe
for soil suitability studies. The suitability classes for groundnut, paddy and finger millet are shown in Table 5. Land suitability for groundnut Land suitability for groundnut, an important oil seed crop of the taluk grown in large area has been worked out. A map showing the distribution of the suitability of soils for groundnut was prepared and depicted in (Fig.1). In the taluk, 34,053 ha (25.08%) of land was classified under moderate to marginally suitable followed by areas which were moderately suitable with 32,328 ha (23.81%) and areas not suitable for groundnut cultivation constituting 17,687 ha (13.0%). The pedons S1, S3, S5, S6, S10, S11 and S12 were moderately suitable whereas S2, S4, S7, S8 and S9 pedons were marginally suitable for cultivation of groundnut. This may be due to poor soil physical properties and low organic carbon content observed in the majority of
the areas. None of the soil series could be grouped under highly suitable class because of moderate to severe soil limitations similar to the findings of Kumar et al. (1999). The major limitations were slope, erosion, texture and soil depth confirming the study of Nagaraju et al. (2001) and Sharma et al. (2001). Land suitability for paddy Land suitability for paddy grown in command areas of major tanks and Pennar river has been worked out. A map showing the distribution of the suitability of soils for paddy was prepared and depicted (Fig.2). Of the total area, 33,989 ha (25.04%) corresponds to moderate to not suitable, 27,694 ha (20.40 %) under not suitable and 17,966 ha (13.23 %) in moderately suitable category for the cultivation of paddy. The pedon S12 was grouped as highly suitable for the cultivation of paddy as it was a valley soil having
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J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151 Table 2 Criteria used in assessing soil suitability for paddy in Pavagada Taluk, Tumkur District.
Sl No.
Soil si te characterist ics
No limit ation 0
1
Slo pe (%)
2
Soil textu ral cl as s
3
4
Ran ge in d egree of limit ations Sl ight Mo derate Severe l im itati on li mitat ion l imitation 1 2 3
Very severe limitation 4
0 -1
1-3
3-5
5-8
-
Loam, sil ty loam, sandy loam
Clay lo am , silt y clay l oam, s an dy clay loam
Lo amy sand , silty clay, clay, san dy clay
Loamy sand, heav y clay
-
Gravel/stones volume(%) Surface Subs urface
<3 <15
3-15 15-40
1 5-40 4 0-75
40-75 -
>7 5 -
Soil depth (cm)
>80
50-80
2 5-50
<25
-
-1
5
CEC (C mol (+) Kg )
>16
10-16
5 -1 0
<5
-
6
Base saturatio n (%)
>80
50-80
3 5-50
<35
-
7
Wetness – Flood ing Drainage class
Mo derate Imperfect (D3)
Stron g Moderately well / Poor (D4 /D2)
Severe Poor / E xcess ive (D2/D7 )
Very s ev ere Excessi ve (D7)
-
8
EC (dSm )
-1
<2
2-4
4-8
8-15
>1 5
nearly level topography, clayey texture and imperfect drainage favoring paddy cultivation. Moderately suitable class was assigned to S1, S3, S5, S6, S8, S10 and S11 pedons and marginally suitable class to S4 pedon as a result of moderate limitation on topography, drainage, texture, gravel content, soil depth and CEC. The pedons S2, S7 and S9 were categorized under permanently not suitable class as these units have severe topographic limitation, stoniness and sandy to sandy loam texture soils. Similar results were reported by Harindranth et al. (2001). Land suitability for finger millet Land suitability for finger millet, a major staple food crop grown in dryland tracts has been worked out (Fig. 3). About 34,054 ha (25.08%) area is classified as moderate to marginally suitable, 32,277 ha (23.78%) was moderately suitable and 17,687 ha (13.03%) under not suitable for finger millet cultivation in the taluk.
The pedons S1, S3, S5, S6, S8, S10, S11 and S12 were classified as moderately suitable and S2, S4, S7 and S9 pedons as marginally suitable for cultivation of finger millet as these soils are situated in undulating lands favoring erosion of top soil and also due to light texture, shallow depth, low organic carbon content and low rainfall. The major limitations include rainfall, topography, texture and soil depth. Khadse et al. (2001) also found similar observations in case of sorghum, pearl millet and pigeon pea. The mapping unit one has been grouped as permanently not suitable for the cultivation of groundnut, paddy and finger millet as this unit consisted of rock out crop which was occupying an extent of 13.03 per cent of the total area. Where ever rock out crops was observed along with other soils, they were grouped under moderate and marginal classes along with not suitable class as an association.
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J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151
Fig. 2 Land suitability for paddy, Pavagada taluk, Tumkur district
Fig. 3 Land suitability for finger millet, Pavagada taluk, Tumkur district
149
J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151 Table 3 Criteria used in assessing soil suitability for finger millet in Pavagada Taluk, Tumkur District. Sl No.
Soil site characteri sti cs
No l imi tatio n 0
1
Rai nfal l (mm )
2
Slope (%)
3
Soil textural class
4
Gravel /sto nes vol ume (%) Surface Subsu rface
R an ge in d egree of lim it at ions Sligh t Mod erate Severe lim itati on l im itati on l imi tatio n 1 2 3
Very severe lim it at ion 4
>750
650 -75 0
500-65 0
400-500
<40 0
1-3
3-5
5-10
10-15
>15
Lo am , si lt l oam , sand y lo am
C lay l oam, sil ty clay loam, sandy clay l oam
Loam y sand, s ilt y clay, clay, sand y cl ay
San d, heavy cl ay
-
0-15 0-35
15 -3 5 35 -5 0
35-50 50-75
50-75 >75
>75 -
5
Soil dep th (cm)
90
50 -9 0
25-50
10-25
<10
6
CE C (C mol (+) -1 Kg )
>16
10 -1 6
5-10
<5
-
7
Base s at urat ion (%)
>80
50 -8 0
35-50
<35
-
8
Drai nage cl as s
M oderatel y drained (D4)
Im perfect ly d rain ed (D3 )
Po or / so me what excessi vel y drained (D2 /D6)
Poor / excessiv el y drained (D2/ D7)
-
The study revealed the importance of land suitability studies for taking up appropriate crop which gives higher productivity. If planning is made based on land suitability studies, then productivity can be enhanced and sustainability in food grain production is possible confirming the studies of Rajkumar et al. (1984). Thus the information on soil resources obtained through use of remote sensing data, field survey and laboratory analysis coupled with GIS helps in drawing meaningful conclusions for taking up alternate cropping systems to obtain better returns without disturbing the ecosystem.
References Kumar AV, Natarajan S and Mani S (1999) Remote sensing for soil resource and land evalution studies in lower palar-Manimuthar watershed. Proc. ISRS Natn.symp., Jan 19-21 1999, Bangalore: pp 136-139 FAO (1976) A Frame work of evalution. Soils Bull., 32, FAO, Rome Harindranath CS, Reddy RS and Krishnan P (2001) Soils of Tumkur district (Karnataka) for land use planning. Report No.553, NBSS & LUP, Regional Center, Bangalore
150
J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151
Table 4 Soil - site characteristics of different soils of Pavagada Taluk, Tumkur District Sl Soil Series No. Association
Topo- Drain- Ground graphy age water class table
Stoniness Surf- SubSoil face Surface depth (cm)
Surface
Texture pH Soil SurfSoil contace control rol section section
OC (%)
CEC (C mol (+) Kg-1)
Base saturation (%)
1
Ballasam-udra
3-5
D5
>10
St0
St1
67
SC
SCL
6.6
6.2
0.45
16.8
83.01
2
Kodama-dagu 5-10
D5
>10
St1
St2
77
SL
SCL
6.3
6.1
0.42
14.50
94.41
3
Kotibande
3-5
D4
>10
St1
St3
22
SC
CL
8.2
8.3
0.58
27.19
88.00
4
Kilarlahalli
0-1
D4
>10
St0
St0
106
SCL
C
8.2
8.3
0.56
29.15
94.48
5
Mangalawada
3-5
D5
>10
St0
St2
92
SL
CL
6.4
6.4
0.43
25.6
89.93
6
Rappam
10-15
D5
>10
St1
St3
44
S
SCL
6.6
6.4
0.35
10.15
87.81
7
Racharlu
3-5
D4
>10
St1
St3
59
C
C
8.3
8.3
0.45
28.13
93.15
8
Shailapura
10-15
D5
>10
St1
St2
89
SL
SCL
6.1
6.2
0.46
14.40
79.44
9
Srirangapura
3-5
D5
>10
St2
St3
56
SCL
SCL
6.2
6.3
0.24
21.60
89.87
10
Srirangapura Tanda
3-5
D4
>10
St2
St3
71
SL
SCL
8.1
8.4
0.27
18.50
74.09
11
Thimmanaikanapete
St0
58
SCL
SCL
8.4
8.2
0-1
D3
>10
St0
Khadse GK, Rajankar PB and Tikekar SS (2001) Land evaluation studies in semi-arid plateau plains in Karmala block, Solapur district, Maharashtra. Proc. of ICORG-2000, Vol.II, 2-5th Feb.2001, Hyderabad: pp 495-501 Nagaraju MSS, Nayak, DC, Verma TP, Ravi Shankar T, Rao BRM and Venkataratnam L (2001) Soils and their suitability evalution for different crops using remote sensing and GIS techniques - A case study in part of Podili Manndal, Prakasam district, Andra Pradesh. Proc. of ICORG-2000, Vol.II, 2-5th Feb.2001, Hyderabad : pp 382-387 Rajkumar AR, Kalbande RJ, Landey and Yadav SC (1984) Soil evaluation for Agricultural land use –
0.58
29.15 89.98
II Productivity potential appraisal. Journal of the Indian Society of Soil Science 32: 467-472 Sharma JP, Rajeev Srinivastava, Bhattacharyya T, Shyampura RL, Saxena RK and Gajbhiye KS (2001) Utilization of remote sensing data in soil resource mapping for land use planning. Proc. of ICROG-2000, Vol. II, 2 - 5th Feb. 2001, Hyderabad: pp 270-275 Soil Survery Staff (1996) Keys to Soil Taxonomy, USDA SCS, Washington DC, US. Soil Survey Staff (1970) Soil Survey Manual, Oxford and IBH publishing Co. Sys C, Van Raust E and Debaveye J (1991) Land Evaluation, Part 2. Methods in Land Evaluation. Agricultural publications No.7, Belgium
151
J. Indian Soc. Remote Sens. (March 2010) 38 : 141-151 Table 5 Soil-site characteristics of different soils of Pavagada Taluk, Tumkur District Sl No
Soi l seri es / Associat ion
1
Rock out crop
Suitabi lit y class wi th per cent of total area Ground nut
% Area
Padd y
% Area
Finger millet
% Area
N2
13.03
N2
20.40*
N2
13.03
?
S2 S2
?
1 3.23
S2 S2
2 3.78
?
2
Ballasamudra Mangal awada
S2 S2
23.8 1
3
Bellib atl u Rock out crop Ballasamudra
S3 N2 S2
3.86*
N2 N2 S2
11.27€
S3 N2 S2
3.86*
4
Bellib atl u Sriran gapu ra Tan da
S3 S2
8 .78€
N2 S2
11.27
€
S3 S2
7.35
5
Kilarl ahalli
S2
23.8 1?
S2
1 3.23
?
S2
2 3.78
6
Mangal awada Rappam
S2 S3
25.08
S2 N2
25.04
¥
S2 S3
25.08
7
Mangal awada Rock out crop Ko tibande
S2 N2 S3
4 .64
¥
S2 N2 S3
2.93
S2 N2 S3
2.84
8
Rappam Rock out crop Mangal awada
S3 N2 S2
3.86*
N2 N2 S2
11.27
€
S3 N2 S2
3.86*
9
Rappam Rock out crop Shailapura
S3 N2 S3
9.58
N2 N2 N2
20.40*
S3 N2 S3
7.54
10
Racharlu Ko tibande Kilarl ahalli
S3 S3 S2
8 .78€
S2 S3 S2
1.48
S2 S3 S2
1.43
11
Shailapura Ko dam ad agu
S3 S2
8 .78
€
N2 S2
11.27
S3 S2
7.35
12
Shailapura Ko dam ad agu Rappam
S3 S2 S3
7.54
N2 S2 N2
9.59
S3 S2 S3
9.58
13
Shailapura Ko dam ad agu Sriran gapu ra
S3 S2 S2
8 .78
€
N2 S2 S2
11.27
€
S3 S2 S2
7.35
14
Sriran gapu ra Rock out crop Shailapura
S2 N2 S3
4 .64
¥
S2 N2 N2
25.04
¥
S2 N2 S3
2.84
15
Sriran gapu ra Sriran gapu ra Tan da
S2 S2
23.8 1
?
S2 S2
1 3.23
?
S2 S2
2 3.78
?
16
Thimm an aik anapete
S2
23.8 1
?
S1
12.39
S2
2 3.78
?
€
€
?
¥
€
€
¥