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Plastic green house

Plastic green house

INTRODUCTION
A greenhouse is a framed or inflated structure covered with glass or plastic where crops could be grown under at least partially controlled environment and which is large enough permit a person to enter into it and carry out cultural operations. Because of considerably lower initial investment, almost all new commercial greenhouse constructions utilize plastics as the glazing material. Green house have a horticultural crops, including rare and medicinal plants, especially under adverse agro-climatic conditions. Greenhouses permit round the year cultivation.

SITE SELECTION AND ORIENTATION OF GREENHOUSE :

A good site can make a difference in the functional and environmental operations of greenhouse. Ground slope for drainage is an important factor. Adequate provision should be made to divert surface water away from the greenhouse.
A greenhouse needs a dependable source of energy in the form of electricity and/or other fuel for environmental control. An electric power distribution line adjacent to the site will reduce the investment on cable laying A short access to all weather public road will facilitate material handling to and from greenhouse. Nearness supply to the market is another added advantage. A dependable supply of good quality water is needed for a greenhouse. Greenhouses should be located away from buildings and trees to avoid obstruction of sunlight.
Orientation of the greenhouse is another important factor. An East-West oriented free standing greenhouse maintains better winter light as compared to a North-South oriented greenhouse. Therefore, in north India, a free standing greenhouse should be oriented in East-West direction.. Gutter connected greenhouses should be oriented North-South to avoid continuous shading of certain portions of the green house due to structural members.
A greenhouse structure has three distinct segments i.e. frame, glazing material and control/monitoring equipment. All the three components have different designed life periods Whereas a greenhouse frame is designed for a service period of 15 to 25 years, glazing materials have lire span or 2 to 20 years, control and monitoring equipment normally wear out in 5 to 10 years.
In the prevailing economic conditions, where capital is a scare input, the choice often favors low initial investment greenhouses. Galvanised mild steel pipe as a structural member in association with wide width u.v.stabilized polyethylene film is a common option selected by greenhouse designers. A 600 to 800 gauge thick polyethylene film can safely withstand normal wind loads prevailing in most parts of the country. A single piece polyethelene film to cover greenhouse is preferred due to material economy, easy handling and improved environmental control. A 800 gauge thick polyethylene film costs approximately Rs.26/square meter and has a service span of 2 to 3 years. The selection of greenhouse equipment depends on local climatic conditions and the crops to be grown. A heating unit is a must in cold regions and a cooling unit is required in all climates in India.
Glass had been used as the sole glazing material till plastics came into existence. Glass has excellent light transmittance and weather resistance but has the disadvantages of brittleness, high cost and heavy weight. Polyethylene and poly vinyl chloride (pvc) films are in use as greenhouse covers. Polyethylene has high light transmittance but lacks durability. U.V. stabilized polyethylene film available in 100 to 250 micron thickness and width of 7m, will last two to three years, depending on quality and local climate. PVC is available as a film or as a rigid panel. PVC with an ultraviolet inhibitor has a life span of 4 years. It is available in 200 to 800 micron thickness and width upto 120 cm. Fibre reinforced plastic (FRP) panels are easy to apply. The problem or discoloration with resulting loss in light transmission and high initial cost have limited their use. They are available upto 120 cm width. Structural panels of double wall glass or rigid plastics are generally used as an energy conservation measure.
The greenhouse frame is the most important component of a greenhouse system. lt provides support for glazing material and a place for fitting of environmental control equipment. Commonly used structural shapes are gable, quonset and gothic arch with minor changes to suit local conditions. Greenhouse frames are designed to withstand wind, snow and crop "loads with minimum obstruction to sun light. Wind and snowfall data are available from the Meteorology department for every part of India. Crop load occurs due to the need to support the plants by using the greenhouse frame. For most of the locations a frame designed to withstand 100 kmph wind speed, is sufficient with the option to use heavier sections in regions of exceptionally high wind speeds.
Tubular steel sections are the most preferred structural members for greenhouse frames. Wood and aluminium are other common materials. Steel pipes provide required strength at a competitive price and also an assured service life of over 20 years.
To meet the demand for construction of low cost greenhouses a tubular frame structure covering the floor area of 4m x 20 m has been developed. Details for construction of the developed greenhouse are given as follows:

STRUCTURAL DETAILS :

The structural members of greenhouse are hoops, foundation, lateral supports, polygrip assembly and end frame. End frames are made of wood and other members are made of galvanised steel.The fabrication details the components have been described below :

HOOPS :

Hoops are the integral part of the greenhouse frame. They are semicircular in shape. Hoops are formed by bending galvanized iron pipe (15 mm dia and 5.9 m length) in a semi-circular shape. For bending of pipes a pipe bender as shown in figure 1 is used. This pipe bender can form pipe in any desired radius. Commercially available 5.9 m (20 ft approx) long pipe is fed by hand into the bender. By rotation of the pulley fitted with a handle uniform bending of pipe is obtained. The central pulley of the pipe bender can be adjusted in such a way that one pass is sufficient to give desired curvature (2 m radius) to the pipe. About 30 cm length on each end remains unbent which enables the ends to easily fit into the foundation pieces

FOUNDATION PIPE

Foundation pipes are meant to provide a firm support to the hoops and to secure the poly grip firmly. Galvanised iron pipes of 25 mm diameter(class A ) and 85 cm length are used as foundation pieces. A 10 cm piece of MS flat (25 x 3 mm) is centrally welded to the one end of pipe and a hole of 8 mm dia is drilled at 10 cm distance from the other end. The flat welded end is put in the dug hole to a depth of 70 cm grouting with concrete as per drawing. A 15 cm length of pipe remains above ground level to hold hoops and polygrip assembly. The foundation pipes are spaced 1.25 m apart in parallel rows. It is important that the tops of these foundation pipes all be at same elevation.

END FRAME

End frames are wooden structures to be fitted on both ends of the greenhouse. The end frame structures are made from 5 cm x 5 cm wooden section. The end frame should have provision for a door and installation of environmental control equipment. ln a smaller size greenhouse (less than 50 square meters of floor) a door is required only on one side while the medium and large size greenhouses may have doors on both ends. The door frame (60 cm x 170 cm) is fabricated from 5 cm x 5 cm wood sections. The open area is covered with either polyethylene film or any other rigid plastic, which is secured to the door frame with wooden battens and nails. The doors, so constructed, are hinged enhance the to the end frames.

LATERAL SUPPORTS

Lateral supports are provided to enhanced the structural rigidity of end frames. These are fabricated from 10 mm dia MS rod. A ring of 3.5 cm dia is made at one end, and a right angle hook on the other. During assembly the ring end encircles the foundation pipe which is put on before putting up hoops. The other end of the lateral support is hooked to the end frame. Four lateral supports are provided at the four corners.

POLY GRIP ASSEMBLY

The polyethylene covering of the greenhouse is to be firmed secured to the foundation pipes, so that it can withstand wind load,. without being blownoff. The polygrip mechanism has been designed in such a way that while it holds polyethylene firmly, puncturing avoided. The polygrip mechanism is made from 20 gauge GI sheet. Two strips of 4 cm and 13 cm width are cut from GI sheet. The 4 cm strip is bent centrally to form a right angle section. The 13 cm strip is bent in the shape of a channel with its edges rounded as shown in the drawing. MS rod of 6 mm dia and 56 mm long pieces are used for positioning channel, angle and polyethylene sandwiched in between and keeping these under pressure. The polyethylene film is stretched and these MS rod pieces are put at a distance of 50 cm, holding the right angle strip against the channel along the whole length of the greenhouse on both sides.

PLASTIC FILM

Ultra violet stabilized polyethylene film of 150 micron to 200 micron thickness is recommended for use in greenhouse glazing. The desured width is 7 m. the film is secured to both sides along the length using the polygrip mechanism and to end frames with wooden nailer. Note Note that a wooden fastening system can be sustituted for the polygrip assembly described above.

RIDGE LINE MECHANISM

In order to keep the hoops at equidistance and increase structural rigidity of the greenhouse structure, the hoops are inter connected with a ridge member. The ridge mechanism for equally spaced hoops is a 15 mm dia GI pipe fastened at the ridge line of the hoops. This ridge line longitudinal pipe is firmly secured to the hoops by the ridge line line grip mechanism which is fabricated from MS
Strapping looped over the crossing of the ridge and hoop and tightened with a bolt as shown in the drawing.

PROCEDURE OF ERECTING THE LOW COST
GREENHOUSE IN THE FIELD

1. A 4 m x 20 m rectangle is marked on the site, preferably orienting the longer dimension in East-West direction. This rectangle wil act as the floor plan of the greenhouse. Make sure that the two diagonals of the rectangle are equal.

2. Mark four points on the four corners of the rectangle. Start from one corner point and move along the length of the marked rectangle, marking a point every 1 25 metre distance until reaching the other corner. The same procedure is repeated on the other side of the rectangle.

3. Dig 10 cm diameter holes to 70 cm depth on all marked points with the help of bucket auger and a crow bar. This way you will get a total of 34 holes on both the parallel sides of the greenhouse floor.

4. Splice polygrip sections formed according to the drawing into two 20 m lengths. Fix the premade polygrip channels to the foundation pipes on 1.25 m spacing with the help of 6 mm dia. bolts. Set these assemblies on temporary supports between the holes with the foundation pipes hanging vertically in the holes and the tops straight and at constant elevation.

5. Pour cement-concrete mixture (1:3:6) around foundation pipes such that the lower 15 cm -20 cm pipe ends are covered in concrete. The concrete is compacted around foundation pipes with the help of the crow bar and is allowed to cure for 2-3 days.

6. After fill soil around the foundation pipes to the ground level and compact it well.

7. Position end frames on the two ends. Mark position of legs. Dig holes for the fixing of legs. Now install both the end frames vertically and duly compact soil on the legs. 8. Put the ring side of support members on adjacent foundation pipe to the corner, and other side is hooked to the end frame.

8. Put all the hoops in the foundation pipes such that the straight portion of hoop is inserted into the foundation pipe and resets on the bolt used for fixing of the polygrip channel.

9. Make a 20 m long ridge pipe by splicing 15 mm pipes together.

10. Put the 20 m long pipe at the ridge line of the hoops. Use cross-connectors on the ridge line pipe such that one half of it remains on the one side of the hoop and the other half on the other side. Put two bolts of 6 mm dia in the holes provided in the ends of the cross connectors and bring the other side closer to it. Now the bolt will pass through the hole of the other half of the cross connector. Tie a few of them with the help of nuts. Repeat the same procedure for joining all the hoops with ridge line pipe. While fixing cross connectors the distance between the hoops/ cross connectors should be maintained 1.25 m (center to center). This grip mechanism will provide a firm grip of the ridge line pipe nd hoops at right angle without allowing for slippage.

11. Spread polyethylene film over the structure from one end to the other without wrinkles and keeping the edges together.

12. Place polyethylene film between the polygrip channel and right angle strip and secure them under pressure with the help of iron rods as shown in the drawing. The film is stretched gently and fixed on the other parallel side by polygrip. This way the polyethylene is secured on both the longer sides.

13. On the other two remaining ends, polyethylene is nailed to the end frames using wooden battens and nails.

14. The remaining portion of the end frames is covered with polyethylene film which is secured with wooden battens and nails. lf fiberglass or other transparent rigid material can be obtained it can be usedon the ends.

15. Mechanical ventilation, Heating and / or cooling equipment is installed on the frames as per the crop requirements (optional).

Bill of material
Galvanised Iron Pipe Construction
4 m x 20 m floor
S.No. Item Specification Quantity

1. G.I. Pipe 15 mm bore, class B 21 pcs, 6 m long
2. G.I. Pipe 25 mm bore, class A 30 m
3. G.I. Sheet 20 guae, 90 cm x 24 cm 4 sheets
4. M.S. Flat 25 mm x 3 mm 4 m (2.5 kg)
5. Nuts, Bolts 6 mm dia, 35 mm long 70 sets
6. Lateral support to end frames 10 mm dia rod 10 m
7. Cement Concrete 1:3:6 1.0 cub. m.
8. Polythylene (Single layer) UV stabilized (800 guage) 154 sq. m. (5.4 sq.m./kg)
9. Miscellaneous (nails, hinges, latches etc.)
10. End frames 5 cm x 5 cm wooden 0.15 cub m wood

(Environmental control equipment as per the local climatic conditions)

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Agriculture in Rajasthan- At a Glance

Agriculture in Rajasthan- At a Glance
1. Agriculture in Rajasthan- At a Glance
Rajasthan is the largest state of India with a geographical area of 34.2 million hectares.

It represents around 10.4 per cent land area of the country. It is situated in North -

Western part of India between 230 3’ and 300 12’ N latitudes and 690 30’ and 780 17’ E

longitudes. The Western and Northern boundaries touch the boundary of Pakistan while in

North and North -East it is bounded by Punjab, Haryana and U.P. The boundary is further

shared in the East and South -East by M.P. and in the South- West by Gujarat. The tropic of

Cancer passes through South of Banswara town. Presently, with an irregular rhomboid shape,

the state has maximum length 869 km from West to East and 826 km from North to South.
Physiography:
Physiographically the Aravallis divide the state into two major physiographic units : i.e.

I.Western plain and II. Central high lands. Which were further demarcated into six sub

units
I.Western plain:
(i) Sandy arid plain (Wa)
(ii) Semi arid transitional plain (Wb)
II. Central high lands:
(i) Aravalli landscape (Ca)
(ii) Eastern Rajasthan upland (Co)
(iii) Pathar &Bundelkhand upland (Cp)
(iv) Malwa plateau (Cm)
The western plain is desert sandy plain, scattered aeolian dunes and interdunal flats. The

Central high lands are mostly alluvial and southern part has heavy soils or rocky eroded

upland mostly hilly in nature. Nearly 40 per cent of the area located primarily in the

Jaisalmer, Barmer, Jodhpur, Bikaner and Churu districts had a variable coverage of dunes

being dominated by longitudinal and coalesced parabolic types. The continuity of these is

interrupted by hills and sheet rock exposures. Physiography of Rajasthan is depicted in

Fig-1

Fig. 1 : Physiography of Rajasthan
Climate:
The climate of Rajasthan ranges from semi arid to arid on the west of Aravalli and semi

arid to sub – humid on the east of Aravalli. Rainfall in the state varies from 920 mm in

South-East to merely 100 mm in the extreme western districts. The distribution of rainfall

is generally erratic, occurring mostly during the period from July to September. About 57

per cent of the total geographical area is arid, 37 per cent semi-arid and 6 per cent is

sub humid to humid. There is a wide variation in the temperature ranging from below

freezing point in winter to sometimes as high as 520 C in summer. Soil temperature at 5-cm

depth ranges from 35 to 450C during monsoon period. In general the month of May is the

hottest and January is the coolest. The mean relative humidity in the afternoon during

summer ranges from 20 to 35 per cent and during monsoon from 48 to 60 per cent. The mean

evaporative rate during summer exceeds 10 mm per day. The highest PET of 2063 mm has been

recorded in Jaisalmer in the West and 1745 mm in the East at Jaipur. The average relative

humidity in Rajasthan is 60 to 66 per cent being as low as 50 per cent in the West to above

80 per cent in the East of Rajasthan. On an average, the wind velocity of 1 to 19 km hr-1

for majority of days is common through out Rajasthan. It is lowest during November and the

highest in June. During the summer months the winds are characteristically dry and warm as

they blow from West to East. Dust storms are common in western Rajasthan, but are few in

eastern Rajasthan.
Soils
The soils of the state belong to 5 orders, 8 sub-orders, 16 great groups, 32 sub groups and

117 soil series . Entisols are dominantly observed covering around 36 per cent area

followed by Inceptisols, Aridisols , Vertisols and Alfisols covering 22.8, 19.55, 2.33 and

0.73 per cent of total geographical area of the state, respectively. The names of the soil

orders, sub-divisions up to great group along with their equivalents in old system of soil

classification are presented in Table 1.1. The distribution scenario of soils in the state

is visualized in Fig 2.

Table 1.1: Approximate equivalent of old and new system of classification.
Order Sub-Order Great Group** Approximate equivalent in old system*
Aridisols Orthids Camborthids
Calciorthids
Salorthids
Paleorthids
Gypsiorthids Sierozems,desert soils

Saline soils of depression

Gypsiferous soils
Argids Haplargids
Alfisols Ustalfs Haplustalfs Red loam, black soils, brown soils, yellowish brown soils of

foothills, alluvial soils
Entisols Psamments Torripsamments
Quartzipsamments Desert soils and sand dunes
Fluvents Torrifluvents
Ustifluvents Alluvial soils (old and recent )
Orthents Torriorthents
Ustorthents
Inceptisols Ochrepts Ustochrepts Brown soils, red and yellow soils of foothills
Vertisols Usterts Chromusterts
Pellusterts Black soils
Source : *Soils of Rajasthan : Survey and classification in Retrospect and Prospect.

Department of Agriculture, Rajasthan, Jaipur 1974-75. ** (Shyampura and Sehgal, 1995)






Agroclimatic Zones :
Based on physiographic divisions of state, its rainfall pattern, soil types, availability

of irrigation water, cropping patterns and administrative units, the state of Rajasthan has

been classified into ten agro-climatic zones (Fig-3). Crops and cropping pattern as

determined by soil and climatic conditions of the zone differ greatly. Major crops of

different districts of Rajasthan are presented in table 1.2

Fig 3: Agro climatic zone of Rajasthan
Vegetation:
A wide variation in the climate of the state has accommodated a large diversity of

vegetation. In the arid zone Prosopis, Capparis and Zizyphus, spp. predominate, whereas in

the most desertic part Calligonum polygonoides is the main species. The semi-arid tract is

dominated by Acacia catechu and Anogeissus pendula. All these vegetation types are

associated with a large variety of annual and perennial grasses and shrubs. The main

vegetation of salt affected soils are salvadora spp., tamarix spp. and prosopis juliflora

as tree spp.
Table1.2: Main features, districts, area, rainfall and crops of the agro-climatic zones of

Rajasthan.
S.N Name of Zone Area
(Mha) Districts covered % of
state area Normal
Rainfall
(mm) Major Crops
I a Arid Western Plain 4.44 Barmer and part of Jodhpur 13.6 100-370 Pearl millet, kharif

pulses, cluster bean
I b

Irrigated North-Western plain 2.06 Sriganganagar &
Hanumangarh 6.0 100-350 Gram, Wheat, mustard, cotton, cluster bean, Pearl millet
I c Hyper Arid partially irrigated Western plain 7.71 Jaisalmer,Bikaner and part of Churu

22.5 100-300 Pearl millet, kharif pulses, cluster bean
II a Transitional Plain of
Inland Drainage 3.69 Sikar,Nagaur,
Jhunjhunu and part of Churu 10.8 300-350 Pearl millet, cluster bean, kharif pulses, gram
II b Transitional Plain of Luni Basin 3.01 Jalore,Pali, part of Sirohi and Jodhpur 8.8 300

-500 Pearl millet, cluster bean, sesame, kharif pulses, wheat, rape and mustard
III a Semi-Arid Eastern Plain 2.98 Ajmer,Dausa,
Jaipur and Tonk 8.6 500-700 Pearl millet, sorghum, sesame, wheat, barley, gram, mustard
III b Flood prone
Eastern Plain 2.70 Alwar,Dholpur
Bharatpur and part of Swai-.Madhopur 6.9 500-700 Pearl millet, sorghum, mustard, wheat

,gram
IV a Sub-Humid Southern Plain and Aravalli Hills 3.36 Bhilware,Rajsamand and part of Sirohi

Udaipur & Chittorgarh 9.8 700-900 Maize, sorghum,
Groundnut, sesame wheat, barley, gram, mustard
IV b Humid Southern Plain 1.72 Dungarpur, Banswara and part of Udaipur and Chittorgarh 5.0

500-1100 Maize, paddy, kharif pulses, wheat, gram
V Humid South-Eastern Plain 2.70 Jhalawar,Kota, Bundi and part of Swai-Madhopur 7.9 650-

1000 Sorghum, maize, sesame, wheat, gram, mustard
Source: Souvenir -25 years of soil based research (1965-90), RAU, Bikaner.
Water resources and land use pattern:
The water resources in Rajasthan state are very limited. These could be classified into two

i.e. (i) Surface and (ii) Ground water. Five rivers viz. Luni, Mahi, Sabarmati, Chambal and

Banas flow through the state. The first three rivers drain into Arabian sea and the rest

two join Jamuna. With an impressive performance of the state the development of irrigation

facilities specially through the canal network and tapping of under ground water, the gross

irrigated area during last four decades has risen from 10.07 lac hectares during 1950-51 to

69.34 lac hectares during 1999-2000 (Table1.3). Available land use pattern in Rajasthan

indicates an increasing trend in the net & gross sown area and area under forest

(Table1.4). The cropping intensity of the state increased from 109.5 per cent (1961-62) to

133.2 per cent (1998-99).
Table 1.3: Source wise net irrigated area in Rajasthan ( ‘000 ha)
Year Net irrigated area Gross irrigated area
Canals Tanks Wells/ Tube wells Others Total Canals Tanks Wells/
Tube wells Others Total
1951-52 - - - - - 224 82 684 17 1007
1960-61 - - - - - 422 255 985 21 1675
1966-67 553 185 1033 22 1794 641 214 1241 23 2120
1971-72 811 179 1151 32 2173 914 192 1298 34 2040
1976-77 867 238 1485 16 2608 1051 255 1651 16 2975
1981-82 946 85 1827 45 2903 1333 201 2239 49 3722
1986-87 1205 124 2054 37 3420 1634 140 2534 40 4350
1991-92 1424 163 2702 54 4343 1856 181 3170 57 5264
1996-97 1534 207 3793 54 5588 2200 218 4266 59 6743
1997-98 1525 182 3657 57 5421 2238 191 4164 61 6675
1998-99 1557 93 3801 48 5499 2275 100 4382 52 6809
1999-2K 1619 78 3866 47 5611 2319 81 4482 50 6934
2000-01 1354 38 3473 42 4907 1976 41 4072 45 6134
Source: Trend in land use statistics. Directorate of Agriculture. GOR,1992-93and Some focus

on Rajasthan, 2002, DES, Jaipur.50 years of Agril. Dev. in Rajasthan, 1999.Stastistical

Deptt., Jaipur
Table 1.4 Land utilization pattern in Rajasthan (Lac ha.)
Particulars 1961-62 1971-72 1981-82 1991-92 1994-95 1998-99 1999-2k 2000-01
Geographical Area 339.9 342.9 342.3 342.5 342.4 342.7 342.7 342.6
Forest 8.79 14.01 20..78 23.70 24.51 25.57 25.80 26.06
Not available for cultivation 63.13 60.51 44.71 43.93 43.37 43.08 43.06 43.06
Other cultivated land excluding fallow land 84.33 79.26 80.75 73.68 69.33 68.01 67.15 66.29
Fallow land 46.26 36.46 40.32 46.33 38.01 45.25 51.48 48.59
Net sown area 137.4 152.6 155.8 154.9 170.2 160.7 155.1 158.7
Gross cropped area 150.5 167.7 186.0 180.9 203.8 214.0 192.9 193.0
Cropping intensity 109.5 109.9 119.4 116.8 119.7 133.2 124.3 121.6
Source: 50 years of Agril. Dev. in Rajasthan, 1999 Statistical Deptt., Jaipur Vital Agril

Statistics, 2000 –2001 &2001-02
Fertilizer consumption and soil fertility:
The consumption of fertilizers in Rajasthan is very low as compare to other states in

India. During 1980 – 81, fertilizer consumption on the basis of cropped area in Rajasthan

was 10 Kg ha-1.Although the farmers of Rajasthan are using more fertilizers now than

before, but it is quite inadequate and also imbalance (Table 1.5).




Table: 1.5 Progress in NPK consumption (,000 t) and NPK use (Kg ha-1) over the years in

Rajasthan
Year NPK consumption (,000 t) NPK use (Kg ha-1)
N P2O5 K2O Total N P2O5 K2O Total
1990-91 242.7 121.4 7.0 371.1 12.9 6.4 0.4 19.7
1991-92 291.9 140.8 8.2 440.9 16.3 7.9 0.5 24.6
1992-93 349.4 136.1 5.1 490.5 18.0 7.0 0.3 25.3
1993-94 366.0 133.8 2.6 502.4 20.2 7.4 0.1 27.8
1994-95 451.1 142.8 8.0 602.0 24.9 7.9 0.4 33.3
1995-96 486.4 150.5 5.7 642.6 25.3 7.8 0.3 33.4
1996-97 546.2 147.0 7.3 700.5 26.8 7.2 0.4 34.4
1997-98 591.8 190.1 5.5 787.4 29.0 9.3 0.3 38.6
1998-99 532.5 188.5 6.1 727.1 25.7 9.1 0.3 35.1
1999-2K 546.0 246.9 6.3 817.2 27.3 11.9 0.3 39.5
2000-01 495.2 164.2 5.3 664.7 22.2 7.4 0.2 35.5
2001-02 583.3 199.7 6.8 788.9 29.1 9.9 0.3 39.3
Source: Fertilizer Statistics 1999 – 2000 and 2002 FAI, New Delhi.
On the basis of report of fertilizer and Agril. Statistics (2000-2001) district wise

fertility status of Rajasthan have been presented in Table 1.6




Table 1.6 Soil fertility status of different districts of Rajasthan
S.No Name of Districts Fertility groups
Available N Available P Available K
1 Ajmer,Alwar,Bikaner,Baran, Bharatpur,Jalore,Nagaur,
Hanumngarh, Chittorgarh Low Medium Medium
2 Jodhpur, Barmer, Jhunjhunu Low Medium High
3 Banswara,Sirohi,Bhilwara, Bundi Medium Medium Medium
4 Churu,Ganganagar, Sikar Low Low to Medium High
5 Dausa, Jaipur, Swai Madhopur Low High Medium
6 Dholpur, Rajsamand, Udaipur Low Medium Low to Medium
7 Dungarpur Low Medium Medium to High
8 Pali, Jhalawar Low Low to Medium Medium
9 Kota Low to Medium Low to Medium Medium
10 Tonk Low to Medium Medium Medium
Nitrogen 0-200 Kg ha-1 Low , 200-400 Kg ha-1 Medium , above 400 Kg ha-1 high
Phosphorus 0 - 20 Kg ha-1 Low , 20 - 50 Kg ha-1 Medium , above 50 Kg ha-1 high
Potash 0 -100 Kg ha-1 Low , 100-250 Kg ha-1 Medium , above 250 Kg ha-1 high


Crop Yields:
Data on the production and productivity trends of major crops in Rajasthan over the last 10

years (Table1.7 & 1.8) reveal that both yield and total production has been increasing

steadily. The productivity of different crops in Rajasthan with an exception for wheat and

pulses are generally low as compared to other states of the West zone of India.
Table 1.7: Stability of food grains production in Rajasthan
Year Yield (kg ha-1) Production (Mt)
1990-91 864 10.93
1991-92 705 7.95
1992-93 894 11.48
1993-94 607 7.05
1994-95 906 11.70
1995-96 805 9.56
1996-97 998 12.82
1997-98 1022 14.03
1998-99 961 12.93
2000-01 880 10.00
2001-02 1099 13.98
Source: Vital Agril Statistics, 2000 –2001 &2001-02 and Fertilizer and Agriculture

Statistics: Northern Region FAI, New Delhi (1998 – 1999)

Table: 1.8 Trend of Productivity of major field crops (Kg ha-1) in Rajasthan
Crops 1961 - 62 1971 – 72 1981 - 82 1991 - 92 1998– 99 1999-2k 2000-01 2001-02
Rice 881 1195 993 857 1220 1260 940 1247
Wheat 981 1249 1659 2517 2487 2540 2404 2793
Pearl millet 244 267 159 233 430 330 441 744
Sorghum 274 274 424 222 288 311 199 414
Maize 1038 994 822 808 1080 1037 1047 1454
Total cereals 505 551 610 835 1188 1155 1036 1341
Chickpea 618 599 650 548 737 695 587 759
Total pulses 417 353 405 324 530 360 306 425
Total food grains 479 499 550 707 982 975 884 1099
Groundnut 521 674 571 798 1090 964 923 1226
Soya bean - - 1000 756 1316 1222 692 1092
Total oil seeds 262 293 488 762 887 937 768 1008
Sugarcane 23265 42954 36646 43871 46913 41421 43154 47484
Cotton 120 196 130 303 230 287 268 94
Source: Basic Statistics, Govt. of Rajasthan. (2000) and Some focus on Rajasthan, 2002,

stastical Deptt., Jaipu

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Nature of salt affected soils and poor quality waters in Rajasthan

Nature of salt affected soils and poor quality waters in Rajasthan
2. Nature of salt affected soils and poor quality waters in Rajasthan.
Rajasthan is the largest state of India comprising of 32 districts spread over 34.24 m ha. At present about 11.22 Lac hectares of land is affected by salinity and sodicity in the state (Sharma, 1998). Considerable area of salt affected soils lies in Jaipur, Bhilwara, Pali, Ajmer , Bharatpur, Bundi, Jodhpur, Kota and Sri Ganganagar districts. Further, all western districts suffer due to this problem. The saline alkali soils in Rajasthan usually occur in association with normal soils of arid and semi arid regions. The contributing factors for the formation of these soils are low rainfall, high temperature and high evaporation, presence of salts at some depth in the soil profile, use of poor quality waters for irrigation in soils having low permeability, high water table and impeded drainage. Excessive use of irrigation water and seepage from canals resulting into rise of water table are also very important contributory factors in the development of saline-alkali soils and water logging in canal command areas. The quality of under ground irrigation water in majority of the areas in arid and semi arid regions is poor. The problem of salt infestation due to use of saline waters for irrigation had covered sizeable area in Jaipur district followed by Ajmer and Pali districts. Jodhpur, Churu, Bikaner, Sikar, Barmer and Jaisalmer districts are also badly affected districts with this problem particularly where under ground saline waters are being used for irrigation. The EC of under ground waters of Jaisalmer, Barmer, Jodhpur, Pali and Nagaur districts varies form 3.0-7.0, 2.9-9.0, 2.0-10.0, 2.9-7.4 and 3.0-8.4 dSm-1, respectively. Saline water problem is more intensive in western Rajasthan (Mehta et.al., 1969).
Soluble salts, which accumulate in saline - sodic soils, consist mainly of chlorides and sulphate of calcium, magnesium and sodium. Usually carbonate, bicarbonate and nitrate ions occur in smaller quantities. Boron also occasionally occurs in small quantities. The nature and proportion of the accumulated salts in soil obviously depend on the source of the salts and nature of soil itself. These salts affect the plant growth either due to their presence in higher quantities or changes in the exchange complex of the soil colloids or by indirect effect on soil microbes and plant root activities, or a combination of all these factors. Chemical analysis of some of the saline alkali soils of Rajasthan is given in table 2.1.
Table 2.1: Chemical analysis of some saline - alkali soils of Rajasthan.
Depth
(cm) pH EC
(dSm-1) Saturation extract analysis (mel-1)
Ca + Mg Na K CO3 + HCO3 SO4 Cl
WELL IRRIGATION
Kaparda ( Jodhpur )
0-15 8.8 5.0 8.9 39.0 0.3 9.0 19.3 20.0
15-35 8.6 14.0 27.6 111.2 0.5 7.0 23.9 108.5
35-50 9.0 18.0 33.7 147.0 0.5 4.0 32.3 145.0
50-95 9.0 11.0 11.3 98.0 0.3 6.0 31.5 72.2
95-115 9.0 12.0 6.6 112.0 0.3 5.0 47.0 86.5
Asalpur (Jaipur)*
0-26 8.7 3.5 2.5 29.0 -- 2.5 6.5 22.5
26-43 8.7 4.2 7.5 35.0 -- 2.0 14.5 26.0
43-84 8.8 3.4 6.0 44.0 -- 2.0 12.0 36.0
84-129 8.8 3.5 2.5 29.0 -- 2.5 6.5 22.5
CANAL IRRIGATION
Digod (Kota)
0-17 8.4 3.9 12.8 27.2 0.2 8.4 12.2 --
17-65 8.8 2.6 7.4 22.1 0.1 19.4 6.2 19.0
65-95 8.8 7.8 33.1 53.0 0.2 10.0 34.0 34.8
95-165 8.2 6.4 31.6 30.0 0.2 17.8 33.0 33.6
Suansars (Kota)
0-15 8.1 10.0 26.5 70.0 0.2 7.6 42.0 49.4
15-40 8.2 8.7 16.2 58.0 0.2 6.0 25.0 54.2
40-68 8.5 7.0 14.9 53.0 0.1 10.2 22.0 33.4
68-95 9.3 1.6 4.9 10.6 0.1 7.8 2.8 5.6
95-105 9.5 2.6 1.9 22.1 0.2 11.4 6.6 9.0

TANK IRRIGATION
Negadiya (Bhilwara)
0-20 8.1 25.0 28.0 220.0 0.1 5.6 164.0 85.0
20-50 8.3 15.0 11.6 135.0 0.2 3.4 120.0 30.0
50-85 8.6 8.0 7.2 78.0 0.2 3.2 64.0 14.2
85-105 8.6 7.5 10.2 63.0 0.2 3.8 60.0 10.8
Source: Saline-Alkali Soils in Rajasthan, their nature, extent and management, Research Monograph-1, Department of Agriculture, Government of Rajasthan, Jaipur.*Vyas et al (1973)

Gypsiferous soils are found in Jamsar, Lunkaransar, Soorsar, Dattor, Sallor distributory and Khusar minor and Mohangarh etc. The soils are shallow, found in intradunal flats at low-lying areas. A consolidated gypsiferous material either as a hard stratum or in powder form is found in soil. The surface soils are generally coarse textured but medium and fine textured soil may also appear in depressions. Most of the deposits are excavated for gypsum and other purposes.
The soil salinity and sodicity problems of Rajasthan are primarily due to irrigation with poor quality water. The severity of the problems is further accentuated by the aridity of the state. About 64.6 per cent of irrigated area (60.2 Lac ha) is covered by well irrigation out of which about 6.15 Lac ha area is affected with the problems of salinity and alkalinity. Saline and alkali soils under irrigation are highest in Jaipur, Bharatpur, Bhilwara and Pali districts. The least affected districts in the state are Udaipur, Dungarpur and Banswara (Table 2.2).
Table 2.2: Salt affected area under irrigation in different districts of Rajasthan
Districts Total irrigated** area (2000-01) Salt affected area under irrigation (`000 ha)*
Canal Tank Wells Inundation Total
1 2 3 4 5 6 7
Ajmer 85.24 -- 1.64 50.06 -- 51.70
Alwar 457.18 1.06 -- 20.80 -- 21.86
Banswara 49.61 -- 0.16 0.40 -- 0.56
Barmer 146.96 -- -- 9.31 -- 9.31
Bharatpur & Dholpur 82.25 3.54 6.12 39.14 5.16 53.96
Bhilwara 115.78 0.10 12.04 91.00 -- 103.14
Bikaner 162.07 -- -- 0.05 -- 0.05
1 2 3 4 5 6 7
Bundi 196.65 35.12 1.02 16.53 -- 52.67
Chittorgarh 100.78 0.24 0.86 51.21 -- 52.31
Churu 76.04 -- -- 0.36 -- 0.36
Dungarpur 14.45 -- -- 0.05 -- 0.05
Sriganganagar& Hanumangarh 135.98 -- -- 0.35 -- 0.35
Jaipur & Dausa 571.98 -- 0.28 139.96 -- 140.24
Jaisalmer 90.41 -- -- 0.19 -- 0.19
Jalore 199.28 -- -- 36.42 -- 36.42
Jhalawar 117.60 -- -- 0.28 -- 0.28
Jhunjhunu 243.56 -- -- 0.59 -- 0.59
Jodhpur 178.04 -- -- 21.56 -- 21.56
Kota & Baran 432.91 10.12 1.02 10.12 -- 21.26
Nagaur 298.40 -- -- 14.40 -- 14.40
Pali 108.94 0.67 -- 102.41 -- 103.08
Swai. Madhopur 223.28 -- -- 1.04 -- 1.04
Sikar 261.52 -- -- 12.60 -- 12.60
Sirohi 44.87 0.12 -- 5.16 -- 5.28
Tonk 149.05 -- -- 0.88 -- 0.88
Udaipur & Rajsamand 36.84 -- -- 0.70 -- 0.70
Total 6019.37 50.97 22.12 615.45 5.16 704.84
Source: * Mehta et al, (1969) ** Deptt. of Statistics Govt of Rajasthan 2000-2001

The salt affected soils in Rajasthan are found in small pockets throughout but they are more dominant in South eastern part of Luni basin and in Ghaggar flood area. In south eastern part of luni basin in Pali, Jalore, Barmer, Nagaur and Jodhpur district about 0.60 mha of naturally saline soils are present. They are generally 50-80 cm deep underlain by lime concretionary horizons. The saline lakes near Sambhar, Didwana and Pachpedra are major source of salts. The salt affected soils in Luni basin generally occur along the river course and in localized micro depressions (Kolarkar et al. 1980)
The problem due to seepage of water under canal irrigation with consequent rising of water table and development of salinity has affected vast areas in IGNP and Chambal command belts in Kota, Bundi, Bharatpur, Chittorgarh and Pali districts.
At present about 1.8 Lac ha land is affected by salinity and sodicity in IGNP Command area. This area is increasing day by day due to extension of irrigation facilities. Salt affected soils in IGNP are mainly located in three areas viz. Anupgarh Branch, Suratgarh Branch and Eastern Block . Maximum area is located in Anupgarh Branch due to bad soil physical properties viz. poor infiltration rate, high bulk density, poorly developed structure, stratification, hard crust formation, tillage problem etc. The soils are predominately clay to silty clay with medium sub angular blocky structure. They are difficult to cultivate when dry and remain wet for longer time than normal soils and are boggy when wet which leads to disruption and delaying in planting and harvesting operation. EC varies from 0.50 to 55.0 dSm-1, pH 8.5 to 9.0 (in certain cases up to 9.8). The flood plain soils of Ghaggar bed are invariably infested with salinity and alkalinity problem. The sodic soils occur in patches and these are mainly found in Tal lands. After introduction of the canal water in the IGNP, water-logging problem has developed. It has been observed that on both North and South sides of Rajasthan Canal feeder, i.e. Badopal, Dabli, Seelwala and Tibi areas, the water table is within two meters. In between Rawatsar and Maseetawali head, the problem is mainly due to seepage of canal water whereas in Lunkaransar lift canal area, the problem is of perched water table. In part of Gaggar flood area, the problem has also developed due to water stagnation in the depressions. In IGNP command stage II, out of total area (8.37 Lac ha) surveyed, 44.5% area has hard pan within 10m depth from surface. If this area is brought into cultivation and excess irrigation is applied, it may also turn into saline one and the problem of water-logging may come up. The status of development of water-logging and salt affected area in Rajasthan and in IGNP are presented in Table 2.3 and Table 2.4, respectively .Trend of water-logging in IGNP is presented in Table 2.5. During 1999 to 2003 the water-logged, critical and potential sensitive areas have shrunken considerably in Stage-I. In Stage –II command the water-logged and critical area have also reduced but there is an increase in potential sensitive area. This overall reduction in the area is attributed to the lack of rainfall and poor availability of water in canal in last three years.
Table 2.3: Water-logged and salt affected area in Rajasthan (' 000 ha)
Water –logged Salt affected
Canal command Un –classified Total Canal command Out side canal command Coastal Total
Rajasthan 179.5 168.8 348.3 138.2 983.8 Nil 1122.0
India 2189.4 2338.1 4527.5 3469.1 3027.0 2069.1 8565.2
Source: Sharma (1998)
Table 2.4 : Area of salt affected soils in IGNP (ha)

Salt affected area Anupgarh Branch Suratgarh Branch Eastern Block
Area (ha) % of
total area Area (ha) % of
total area Area (ha) % of total area
Highly 73850 27.2 19930 17.1 37230 23.7
Moderately 34580 12.7 7830 6.7 -- --
Total 108430 39.9 27760 23.8 37230 23.7
Source :UNDP,F.A.O.(1971)

Table 2.5 Waterlogged area in IGNP command
S No
Type of Area
Stage Total area (ha)
96– 97 97-98 98-99 99-2K 2k-01 01-02 02-03 03-04
1. Potentially sensitive area (water table within 1.5 to 6.0 m ) I
II 297820 310056
17303 298760
18067 280023
19666 225153
12184 179170
18304 164375
24572 195000

13481
2. Critical area (water table within 1.0 to 1.5 m) I
II 24140 28760
3610 27960
3792 26430
5088 13425
2229 11355
1261 8750
453 9259
317
3. Water logged area (water table within 0.0 to 1.0 m) I
II 17220 22008
1243 19492
1243 18150
1466 12672
369 10098
78 5755
16 2531
04
Source: CAD Commissioner IGNP, Bikaner 2003-04
Sharma et al. (1968) observed that in canal irrigated area of Pali district problem of soil had developed due to higher water table , whereas, in well irrigated areas the problem of salinity and alkalinity is due to use of saline under ground water.
High water table with soil salinity and sodicity is also a common problem of irrigated areas of Chambal command in Rajasthan. Out of total area surveyed in Chambal command, 16192 ha area was salt affected (table 2.6). The rise in water table was attributed to canal seepage and over irrigation. Generally the shallow ground waters have EC values > 1.5 dSm-1 with recorded values as high as 20 to 50 dSm-1 (Anonymous, 1974). The soils of the command area are fine textured consisting of tough clay, which are slowly permeable, calcareous and highly expanding. These soils occur in nearly level to gentle sloping (0.08%) land. Top soil of Kota series are 1.2-2.5 m deep with high clay content and very slow permeability.

Table 2. 6: Distribution of salt affected area (ha) in Chambal command
S.No. Saline/ Sodic Soil Area ( ha) (%)Area
1. Saline EC >4 dSm-1 5652 9.52
2 Saline Sodic EC >4 dSm-1 & SAR >15 8415 14.18
3 Sodic EC <4 dSm-1 & SAR >15 2125 3.58
Total Salt Affected Soils 16192 27.28
Source : Anonymous (1974).
Lal et al. (1971) reported that in Jobner tract there was no salinity problem but these soils had alkalinity problem. Mali (1971) observed that in Boraj- Mehla tract ground water fell in three classes C4S4, C3S2 and C2S1. The saline nature of under ground water, high water table, impermeable hard kankar pan, low tophographical situation, salt deposits in vicinity of the areas and aridity of the tract, were traced out to be the most important factors responsible for development of salt affected soils in the area.
Jat (1972) observed that principal caused for origin of salt affected soil in Nava tract (Jaipur) appeared to be saline nature of underground water, high water table, low topographical situation and salt deposits in vicinity of the tract.
Mathur et al. (1968) reported that Rajasthan has wide spread problem of salinity and alkalinity of soils which was mainly located in districts of Jodhpur, Pali, Bhilwara, Ajmer, Jaipur, Bharatpur, Alwar, Chittorgarh, Jalore, Nagaur and Sirohi constituting about 15.0 per cent of cultivated area.
Dhir et al. (1979) found that in Pali block of Rajasthan the salinity was high to very high in 25% area of the block. Studies on genesis and taxonomy of wide spread saline and sodic soils in Bharatpur district revealed that clay migration was responsible for formation of argilic and natric horizones in three pedons classified as Typic Haplustalf, typic Natrustalf and Aquic Natrustalf, based on sub surface diagnostic horizones and soil moisture regimes, as influenced by micro topographical positions. Two pedones were classified as Aeric Halaquept and typic Salorthid (Qureshi et. al. , 1994). Kameria (1995) reported that sub surface soils of Zone IIa ( Transitional plain of inland drainage) of Rajasthan have five salinity and alkalinity classes (i.e. S1, S2, S3,S4 and S5) Panwar (1996) classified the soils of Jobner tract in order – Entisol sub-order- Natripsamments, further these soils have been grouped in Ustinatripsamments – great group.
Sikarwar (1997) reported that most of the soil of Bharatpur tehsil were alkaline and highly saline in nature. Ram (1998) found that most of the irrigated soils of Pali tract were alkaline and highly saline in nature while unirrigated soil of the tract were slightly alkaline and moderately saline in nature. Singh (1994) observed that SAR & RSC of underground water of Chirwa panchyat samiti ranged between 2.84 to 17.2 and 0.1 to 6.0 mel-1, respectively and these waters were characterized in to C4S4, C4S3, C3S3, C3S2, C3S1, C2S1 and C2S2, classes.
In command area of North- West Rajasthan, waterlogging and soil salinity has been emerging as a serious problem covering 0.36 m ha land (Deo and Yadav,1999). The lower available water capacities (6.0-14.4 cm m-1) and higher infiltration rate (10.9-13.5 cm hr-1) of most of the soils of the region caused perched water. Soils are saline sodic and were loaded with chlorides and sulphates of sodium. The underground water was found Na- Mg-Ca types with dominance of chlorides followed by bicarbonates.
Oswal (1999) reported that Sambhar Panchayat Samiti of Jaipur had moderate salinity and slight alkalinity problem. The soils of Bhilwara, by an image interpretation coupled with field studies was Taxonomically classified at family level in order Inceptisol and Entisol. Of total area of 129501 ha , soils are distributed as 11384, 27677 and 55587 ha Saline, sodic and saline-sodic , respectively ( Sharma and Totawat, 2000).
Waters from different sources and their Properties:
The general properties of water include pH, presence of salts, their chemistry (nature of dissolved salts), organic matter, seeds, spores, bacteria and other micro-organisms. The properties differ from water of one source to another depending upon the origin. Rain water has been considered to be of the most fresh quality although its fertility is poor. River and canal water are usually fresh and sometimes alkaline but are very conducive from the fertility point of view. Ground water may be either good or alkaline /or saline.
Rain water:
Chemical composition of the rain water from five places in Rajasthan located at different precipitation isohytes and having different types of soils and environmental conditions, is reported in Table 2.7. The pH of rain water varied from 7.2 to 8.3, whereas, normal water in the atmosphere is in equilibrium with CO2 and has a pH of 5.7. The total soluble salt concentration varied from 37.4 to 143.7 mgl-1. Among anions, chlorides dominated over sulphates. The occurrence of saline water irrigated soils and a large number of dyeing industries at Pali seem to be the causative factors for the presence of excessive Na and Cl ions in the rain water over Pali (Agarwal, 1986).
Table 2.7: Chemical composition of rain water (1975-1977) over
Rajasthan
Location pH EC
(Scm-1) Ionic composition (mgl-1)
Cl- NO3- SO4 –2 Na+ K+ Ca++ Mg++
Palsana (Sikar) 7.8 83.3 4.5 0.83 1.12 4.8 5.4 11.3 1.97
Pali 8.3 143.7 27.1 1.15 0.83 28.8 2.4 12.7 1.87
Jodhpur 7.5 37.4 9.5 0.56 0.87 3.3 1.1 5.4 1.00
Bikaner 7.8 38.6 12.2 0.85 0.75 7.5 4.5 5.2 1.18
Jaisalmer 7.2 71.9 6.4 3.06 1.56 7.5 10.3 12.1 1.10
Source: Agarwal (1986)
Canal water:
Darra et. al. (1964) reported that canal waters in Rajasthan are of good quality .The average water has a pH and EC of 7.8 and 0.4 dSm-1, respectively. SAR and RSC were around 6.0 and 1.36 mel-1, respectively. In Rajasthan, the canal waters of Chambal, Jawai, Bagolia, west Banas and IGNP are suitable for agricultural use. The water of Ora dam is, however, highly saline primarily because of main nalah feeding the dam flow through a saline patch (Mehta et.al., 1969). According to UNDP reports (1970) waters of IGNP command had average value of pH 7.8 , EC 0.2 dSm-1, respectively, SAR and RSC were around 1.02 and 1.36 mel-1, respectively.
Lakes:
In Rajasthan, there are many important salt lakes, for example, Sambhar, Didwana, Pachbhadra and Phalodi which contribute to more than 25 per cent of the total salt ouput of India. The overall salinity of the lake waters is by far the highest on the earth qualifying them to be called as brine. The chemical composition of the brines collected from the four salt lakes is presented in Table 2.8.
Table: 2.8: Chemical analysis of brines of different salt lakes of Rajasthan
Constituents * Locations
Sambhar Didwana Pachbhadra Phalodi
pH 8.28 8.9 7.26 7.23
Cl- 119535 (12)** 166725 (17) 143183 (14) 130225 (13)
SO4 - 22854 (2.3) 54910 (5.5) 14108 (1.4) 12258 (1.2)
HCO3- 3586 2639 267 60.5
CO3 -- 3705 628 Nil Nil
NO2- 1319 0.05 9.85 0.90
NO3- 3.33 1.05 32.68 1.6
Ca++ Nil 23.2 63.6 950
Mg++ Nil 85.5 12219 990
K+ 461 580 3289 939
NH4+ Nil 3.5 0.16 n.d.
B 70.2 171.5 24 5.1
TDS 282349 (28.23) 371098 (37.11) 301543 (30.15) 240308 (24.03)
Source: Chaudhury et al. (1966) * All the constituents except pH are expressed as mgl-1
** Figures in parentheses express weight in g per 100 cc of brine.
Tanks:
The quality of tank waters irrigating a large acreage in Ajmer, Bhilwara, Jaipur, Alwar and Bharatpur districts is invariably normal for the crop cultivation (Mehta et al., 1969)
Ground water:
The ground water in the arid zone of Rajasthan, the Great Indian Desert, occurs in rocks ranging in age from the Precambrian to the quaternary system. In hard crystalline rocks, such as gneisses, schist, phyllites and quartzite, the ground water occurs and moves through the joints, fractures, foliation planes and weathered zones, whereas in sedimentary rocks, like sandstone, the ground water occurs and moves through the pore-spaces and interstitial openings of granular sediments.
Ground water in western Rajasthan generally occurs under water-table conditions (unconfined) in hard crystalline and alluvial formations. In sandstone of tertiary and older ages, ground water also occurs under semi-confined to confined conditions owing to the presence of overlying impermeable horizons. The depth to which water is available in the arid zone ranges from less than 10 m to as high as 140 m below the land surface. The deepest water table has been observed in the area south of Bikaner in Rajasthan.
The ground water department of Rajasthan has carried out a very systematic survey of the quality of ground waters in Rajasthan. Percentage distribution of ground waters based on about 10,000 samples, with respect to salinity in various districts shows that as rainfall increases from the arid districts of western Rajasthan to the semi arid districts in eastern Rajasthan, the average quality of ground water improves. In arid-cum-semi-arid districts the percentage of saline water (EC>5 dSm-1) is appreciably high, varying from 30-50 per cent in nine districts, namely, Barmer, Bikaner, Churu, Ganganagar, Jaisalmer, Jalore, Jodhpur, Nagaur and Pali. EC of some ground waters is 10 to 15 or even higher than 15 dSm-1. The highest EC of 49, 35, 34 and 22 dSm-1 have been recorded in ground waters of Bikaner, Ganganagar, Barmer and Jaisalmer districts (Gopal and Bhargava, 1981). The percentage of such waters in Jhunjhunu and Sikar districts is relatively low. In the seven semi-arid districts, EC is generally less than 10 dSm–1, except Bharatpur district where ground waters are of as poor a quality as in the arid districts. The percentage of saline ground waters varies from less than 5 to 15. In mid districts, the percentage of saline waters is negligible except in the Bundi district. In sub-humid districts, EC is largely less than 2.2 dSm-1 except in Kota. Ground water department of Rajasthan has prepared a map showing quality of waters in Rajasthan. The map is presented in Fig 4.












Fig. 4 : Quality of underground waters of Rajasthan
The classification of the ground waters of Rajasthan in three groups, namely, (a) arid and arid-cum-semi-arid districts; (b) semi-arid districts; and (c) humid and sub-humid districts, and their distribution in different salinity classes, brings out a very interesting picture. About 90 per cent of the ground waters in the western arid districts have EC less than 10 dSm-1, whereas in the semi-arid and humid districts 90 per cent waters have EC less than 5 and 2.2 dSm-1, respectively (Table2.9).
Table 2.9: Percentage distribution of ground waters of Rajasthan in different salinity classes
District No. of samples (10329) EC (dSm-1)
<0.75 0.75 – 2 2.2 – 5 5 – 10 10 – 15 >15
Arid
Barmer 322 10 11 31 27 15 7
Bikaner 137 2 27 37 21 10 3
Ganganagar 361 7 36 23 20 10 4
Jaiselmer 295 19 37 20 20 4 1
Jodhpur 357 8 38 27 16 8 4
Arid-cum semi-arid
Churu 244 3 16 30 29 15 7
Jalore 505 10 28 30 20 10 3
Jhunjhunu 363 8 47 34 11
Nagaur 459 8 36 28 22 4 3
Pali 498 12 34 20 17 9 8
Sikar 174 12 55 28 5 - -
Semi-arid
Ajmer 388 15 52 26 7 - -
Alwar 764 23 60 14 3 - -
Bharatpur 499 20 31 19 14 16 -
Bhilwara 572 18 52 20 10 - -
Jaipur 939 30 45 18 7 - -
S.Madhopur 505 26 52 16 6 - -
Tonk 333 10 50 26 14 - -
Sub-humid
Chittorgarh 442 35 61 4 1 - -
Bundi 238 38 43 17 - - -
Udaipur 640 23 64 10 2 - -
Sirohi 94 55 37 17 - - -
Humid
Banswara 296 73 26 1 - - -
Dungarpur 189 55 41 3 - - -
Jhalawar 243 60 34 6 - - -
Kota 472 30 57 12 1 - -
Source: Gupta (1979).
SAR value of ground waters in some districts of Rajasthan has been shown in Table 2.10 .It is apparent that values as high as 96 or 114 are noted in the waters of Nagaur and Jodhpur districts. The ground waters of arid districts have relatively higher values than the semi-arid districts. Sodium Adsorption ratio of ground waters in western Rajasthan are usually greater than 20, in eastern Rajasthan SAR values rarely exceed 20. For example, in Alwar district, the percentages of ground waters having values of SAR less than 10, 10-20 and greater than 20, are 76, 21 and 3 respectively. Distribution of underground water according to EC and SAR is presented in Table 2.11.
Table 2.10 : SAR values of ground water in Rajasthan
District No. of samples SAR
Range Average
Arid
Barmer 290 1.2 – 32.4 --
Bikaner 137 0.6 – 56.1 --
Ganganagar 200 1.1 – 36.0 --
Jaisalmer 318 1.4 – 26.8 --
Jalore 50 12.0 – 53.6 24.7
Jhunjhunu 9 12.5 – 19.6 33.5
Jodhpur 74 3.7 – 113.6 --
Nagaur 74 15.8 – 95.7 31.7
Pali 84 3.8 – 63.8 21.9
Sikar 14 3.6 – 17.2 --
Semi-arid
Ajmer 19 3.3 – 69.5 --
Alwar 340 0.2 – 61.5 --
Bharatpur 10 2.8 – 77.8 --
Bhilwara 118 4.1 – 73.3 23.3
Jaipur 92 4.8 – 39.9 16.1
Sub-humid
Udaipur 166 1.8 – 18.9 6.4
Source: Gupta (1979).


Table 2.11: Percentage-wise distribution of ground waters of western Rajasthan in different EC and SAR classes
EC (dSm-1) No. of samples (2278) SAR
<10 10 – 18 18 – 26 26 – 34 >34
<0.25 3 66.7 33.3 -- -- --
0.25 0.75 167 93.4 5.4 1.2 -- --
0.75 – 2.25 607 72.8 21.9 3.6 1.8 0.3
2.25 – 5.0 659 31.0 39.4 22.3 4.7 2.6
5 – 10 496 6.6 28.4 31.9 21.2 11.7
10 – 15 225 2.2 12.5 30.7 33.3 21.3
>15 121 3.3 4.1 12.4 22.3 57.9
Source: Dhir (1977).
The tube well waters of Jodhpur and Pali districts were reported to be very high in EC, SAR and chloride content ( Shankaranaryan et al.,1965), while those from B
Bhilwara, Ajmer and Bharatpur districts were found to be moderate to highly dominated by the sodium salts ( Mathur et al.,1968). Tube-well waters of Nagaur district were classified as highly saline having sodium as the dominant cation (Paliwal and Gandhi, 1967). The tube-well waters of Sriganganagar, Bikaner, Churu, Jalore, Nagaur, Jaisalmer and Jodhpur have high salinity and low to medium sodium hazard ( Puntamkar et al.,1967; Raghava and Joshi, 1967).
In the ground saline waters of western Rajasthan, the incidence of occurrence of RSC is less. The percentage of waters having RSC>2.5 mel-1 was 0, 14, 4, 0 and 20 in districts of Barmer, Jaisalmer, Jalore, Jodhpur and Pali, respectively (Mehta et al., 1970). In Nagaur district, RSC in ground waters varied from 0 to 21.5 mel-1, with an average value of 4.1 mel-1 (Paliwal and Gandhi, 1977). In Ajmer, Jhunjhunu and Sikar districts, RSC was generally less than 10 mel-1 (Singh and Mahnot, 1976). In high rainfall districts namely, Bundi and Jhalawar more than 75 pr cent ground waters have RSC less than 2 mel-1 (Gupta et. al., 1974; 1975).
Sodium dominates invariably in all the waters followed by magnesium and calcium. The percentage of sodium ions varies from 60 to 80 of the total cation concentration. The ratio of magnesium to calcium varies from 1 to 5. Amongst anions, chlorides dominated in all the districts except in Ajmer where sulphates dominated. The second anion was generally bicarbonate in well waters of such districts as had an average EC between 2 and 3 dSm –1. In the remaining districts sulphate was the dominant anion and such districts had an average EC >4 dSm-1 (Table 2.12).
Table 2.12: Mean chemical composition of ground waters in some districts of Rajasthan
District
No. of Samples pH
EC
(dSm-1) Ions (mel-1)
Na K Ca Mg Cl SO4 CO3 HCO3
Ajmer 19 8.7 5.5 37.7 0.28 4.86 5.50 10.2 24.76 0.80 9.70
Alwar 334 8.2 2.4 14.9 - 3.57 6.85 12.2 8.82 2.85 8.42
Barmer 339 7.9 5.2 38.8 1.60 4.73 7.13 38. 6.18 - 6.40
Bharatpur 276 8.3 3.1 20.2 - 3.70 8.70 16.5 8.20 0.50 8.40
Bhilwara 235 8.1 5.5 39.6 0.84 5.05 5.34 42.0 11.43 0.40 8.35
Bikaner 249 7.8 6.3 45.5 0.98 8.10 9.20 46.2 12.20 - 6.90
Jaipur 161 8.3 3.0 35.1 0.32 3.61 11.40 29.7 11.10 3.74 8.34
Jaiselmer 318 7.7 5.0 33.4 0.72 5.42 4.74 30.6 7.16 0.86 6.55
Jalore 472 8.0 3.3 34.8 1.01 4.96 6.19 33.2 5.50 - 6.91
Jodhpur & Nagaur 943 8.0 5.5 38.8 1.24 4.20 8.35 36.7 8.67 - 9.73
Pali 573 8.0 5.1 39.2 - 5.49 6.64 22.7 10.85 1.12 8.21
Sirohi 28 7.6 2.9 23.5 - 4.62 2.49 19.5 3.39 2.00 8.15
Ganga nagar* 138 7.6 4.3 18.7 0.6 8.8 10.1 20.5 - 1.1 5.0
Hanumangarh* 72 7.7 2.8 10.7 0.9 3.7 7.6 11.6 - 1.1 6.2
Source: Paliwal (1972, 1978) *Yadav et al.( 1998)

On an average, potassium ion was either absent or occurred in amounts less than 2 mel-1. Likewise, amongst anions, carbonates contributed the least and did not exceed 4 mel-1. Thus, in general well waters of Rajasthan could be characterized as Na-Mg-Ca cation type and Cl-HCO3-SO4 anion type in the low salinity class (EC <3 dSm-1) and Cl-SO4-HCO3 anion type in the higher salinity class (EC>5 dSm-1). As EC of water increases from low to high, percentage of divalent cations decreases (Table2.13).A large number of waters which contain Ca+Mg more than 50 per cent have EC less than 2.25 dSm-1 and waters with EC greater than 4 dSm-1 usually contain less than 30 per cent Ca+Mg (Table 2.13)
Table 2.13: Percentage-wise distribution of ground waters of some districts of western Rajasthan on the basis of conductivity and divalent cation percentage
EC
(dSm-1) Divalent cation percentage
(>50) (30 – 50) (<30)
Jaisalmer Bikaner Barmer Jaisalmer Bikaner Barmer Jaisalmer Bikaner Barmer
<0.25 0.8 - - - - - - - -
0.25– 0.75 7.6 0.8 0.9 1.2 0.8 1.3 0.8 - 0.4
0.75– 2.25 18.9 6.4 11.1 4.2 12.0 7.0 6.4 6.3 6.6
2.25 – 4.0 1.6 2.8 6.6 5.4 8.2 4.8 7.4 11.5 7.4
4.0-6.0 2.0 2.0 2.2 2.4 0.8 7.1 12.0 6.2 11.5
6.0-12.0 2.4 3.2 1.8 6.4 5.0 4.1 13.6 17.0 18.2
>12.0 0.8 0.4 0.4 2.0 3.8 0.4 4.0 13.0 8.2
Source: Bhandari et al.,(1971)
Percentage-wise distribution of ions with respect to different salinity classes (Table2.14) shows that with an increase in salinity the proportion of sodium and chloride ions increases whereas, calcium, magnesium and carbonate plus bicarbonate decreases. However, the proportion of sulphate ions increases regularly up to a mean value of 8 dSm-1 and then decreases in highly saline waters (Paliwal, 1972). The quality of ground water varies with soil type but it is difficult to correlate them ( Darra et. al., 1964).
Table2.14: Percentage-wise distribution of ions in relation with EC in groundwater of Rajasthan
Ions EC(dSm-1)
<2 2 – 6 6 – 10 >10
Na+ 51.9 70.3 72.2 74.1
K+ 1.5 3.2 2.3 1.6
Ca++ 20.4 9.4 .9 9.2
Mg++ 26.2 17.1 16.6 15.1
Cl- 30.3 54.1 67.2 75.3
SO4= 10.3 15.3 20.4 15.2
HCO3 -+CO3= 59.3 30.6 12.4 9.5
No. of samples 1671 1372 545 344
Percentage 42 35 14 9
Source: Paliwal (1972)
The tube-well waters from Bhilwara district of Rajasthan revealed that waters high in bicarbonate were associated with low total salt concentration and bicarbonate constituted as high as 60 per cent of total anions. The EC of waters having RSC more than 2.5 mel-1 mostly ranged between 1 to 2.5 dSm-1 ( Ram Deo, 1978).
Studies conducted by Gupta (1991) revealed that ground waters are sodic in character due to high SAR or RSC values. The SAR ranges from 0.15 to 176.8 with an average value of 13.9. In Barmer, Bikaner and Jaisalmer districts more than 33.3 per cent waters have SAR more than 18.High RSC generally occurs in low to medium salinity waters and ranges form nil to 68.8 mel-1 with an average value of 3.1 mel-1. The districts viz. Jhunjhunu (42.5%), Nagaur (32.3%) and Sikar (30.2%) have high RSC (more than 5 mel-1) in ground water.
Lot of work has been done under the aegis of AICRP on management of salt affected soils and use of saline water on quality of underground water of Jaipur, non-command area of Bikaner, Churu and part of Nagaur districts. In Bikaner, Churu and part of Nagaur districts from last decade only the farmers are installing tubewells in their fields and have started irrigated agriculture. Thus the quality of underground waters which had been quoted by earlier workers was related to the water (wells) which were dug by PHED and used for human consumption and not for agricultural purposes. Work on ground water quality done under the above mentioned project is highlighted below.
Jaipur District :
Twelve tehsils of Jaipur district viz. Kotputali, Viratnagar, Amber, Jaipur, Sanganer, Bassi, Dudu, Phagi, Chaksu, Sambhar, Jamva Ramgarh and Dausa were surveyed to know the underground water quality. Vyas et.al. (1993) reported that in underground water of Jaipur district the pH ranged between 7.0 to 9.0. EC of 79.5 percent samples was less than 4 dSm-1 and of 62.5 percent samples it was even < 2.0 dSm-1. In case of Bassi, Dausa, Dudu, Phagi and Sambhar tehsils, more than 10 percent samples had EC>6 dSm-1. Except Sanganer, Bassi and Sambhar tehsils, more than 54 percent samples had RSC < 2.5 mel-1 and about 7.5 to 27.1 percent samples had RSC between 2.5 to 5.0 mel-1. Sanganer and Sambhar tehsils had more than 40 percent samples having RSC > 5.0 mel-1. On an average 57.8, 19.5, 15.0 and 7.5 percent of total samples had RSC < 2.5, 2.5-5.0, 5.0-10.0 and > 10.0 mel-1, respectively. In Kotputali, Viratnagar, Amber, Jamva Ramgarh and Jaipur tehsils more than 80 percent samples had SAR value of < 10. Whereas, in Sanganer, Phagi, Chaksu, Sambhar and Dausa tehsils 34.4 to 41.5 percent samples had SAR between 10 to 20. In Sambhar and Dudu tehsils more than 30 percent samples had SAR>20. Range of chemical characteristics of tubewells/open well waters and distribution percentage of samples of different tehsils of Jaipur District falling into different ranges of pH, EC, RSC & SAR are given in Table 2.15 and 2.16, respectively.
Table 2.15: Range of chemical characteristics of Tubewells/Open well waters of various tehsils of Jaipur District
Chemical Characteristics Tehsils
Kotputali
(53)* Viratnagar
(70) Amber
(207) Jaipur (107) Sanganer (53) Bassi
(59)
pH
EC (dSm-1)
Ca++ (mel-1)
Mg++ (mel-1)
Na+ (mel-1)
K+ (mel-1)
CO3-2+HCO3-1 (mel-1)
Cl-1 (mel-1)
RSC (mel-1)
SAR 7.0-9.0
0.6-7.0
2.4-22.2**
--
1.0-47.2
0.1-2.0
4.0-16.0

0.8-52.2
Nil-12.4
0.7-19.8 7.3-8.8
0.9-7.0
1.4-22.6**
--
1.0-46.0
0.1-0.5
4.0-18.0

0.8-47.0
Nil-11.0
0.6-15.2 7.2-9.0
0.4-2.9
0.2-4.0
0.0-10.0
1.0-24.0
--
1.8-10.0

0.0-156.0
Nil-11.9
0.6-21.9 7.1-8.2
0.5-6.1
0.2-0.6
0.4-15.7
1.0-41.0
0.01-1.0
1.6-16.0

0.8-46.2
Nil-18.2
0.4-30.8 7.0-8.7
0.6-6.5
0.6-15.6**
--
1.0-54.2
0.1-0.5
3.2-27.0

1.0-46.6
Nil-19.2
0.6-25.5 7.3-8.8
0.5-21.5
0.8-71.4**
--
1.0-140.0
--
3.3-20.6

1.0-182.4
Nil-20.6
0.6-26.1
Dudu (209) Phagi
(59) Chaksu
(61) Sambhar (162) J. Ramgarh (48) Dausa
(53)
pH
EC (dSm-1)
Ca++ (mel-1)
Mg++ (mel-1)
Na+ (mel-1)
K+ (mel-1)
CO3-2+HCO3-1
(mel-1)
Cl-1 (mel-1)
RSC (mel-1)
SAR 7.1-8.9
0.5-17.6
0.2-0.3
1.5-68.4
1.6-156.0
--
tr-43.0

1.0-158.5
Nil-20.6
1.1-97.8 7.2-8.9
0.7-12.0
2.2-69.6**
--
2.0-84.5
0.1-0.40
4.9-26.4

1.0-120.6
Nil-19.4
1.2-29.3 7.3-8.7
0.6-8.2
1.6-57.6**
--
2.5-46.6
--
3.4-17.4

2.2-53.0
Nil-12.1
1.3-18.3 7.0-8.4
0.6-41.6
0.5-21.5**
6.0-57.0
3.0-260.0
--
4.0-40.0

1.0-235.0
Nil-36.5
1.5-52.0 7.4-8.8
0.4-2.3
3.0-11.1**
--
1.2-72.0
--
2.5-17.5

1.5-66.0
Nil-12.4
0.6-16.8 7.0-8.8
0.6-10.0
tr-35.0**
--
3.5-102.2
--
2.2-20.6

2.0-118.0
Nil-19.6
2.0-41.8
Source : Vyas et al. (1993) * Number of samples tested ** Figures are of Ca + Mg
Table 2.16 : Distribution (percent) of water samples of different tehsils of Jaipur District falling into different ranges of pH, EC, RSC and SAR
Tehsils pH range EC range (mel-1)
7.0 -7.5 7.5 - 8.0 8.0 - 8.5 > 8.5 < 2 2 - 4 4 - 6 6 - 8 > 8
Kotputali
Viratnagar
Amber
Jaipur
Sanganer
Bassi
Dudu
Phagi
Chaksu
Sambhar
Jamva Ramgarh
Dausa 1.9
2.9
6.8
22.4
3.8
13.6
9.6
11.9
14.8
34.6
4.2
17.0 13.2
28.4
20.3
59.8
52.8
30.2
43.5
62.7
49.2
48.8
22.9
34.0 56.6
57.2
28.5
16.9
33.9
32.2
37.8
20.3
32.8
16.6
66.6
41.5 28.3
11.4
44.4
0.9
9.4
23.9
9.1
5.1
3.3
--
6.3
7.5 64.2
91.4
96.6
88.8
69.8
61.0
14.5
39.7
52.5
29.6
91.7
62.2 22.6
7.1
3.4
2.8
24.5
20.0
24.6
36.2
37.7
30.8
6.3
17.0 7.5
--
--
7.5
3.8
13.6
26.6
13.8
6.6
15.4
2.0
11.3 5.7
1.4
--
0.9
1.9
1.9
14.5
5.2
1.6
10.5
--
5.7 --
--
--
--
--
3.4
19.7
5.2
1.6
13.7
--
3.8
Average 12.1 37.6 35.6 14.7 62.5 17.0 10.0 4.9 5.6
Tehsils RSC (mel-1) range SAR range
< 2.5 2.5 - 5.0 5 -
10 > 10 < 10 10 - 20 20 - 30 > 30
Kotputali
Viratnagar
Amber
Jaipur
Sanganer
Bassi
Dudu
Phagi
Chaksu
Sambhar
Jamva Ramgarh
Dausa 60.4
67.1
66.2
57.0
30.2
45.8
64.3
57.6
62.3
37.7
58.3
54.7 20.8
21.4
22.2
27.1
7.5
17.0
13.9
22.0
18.0
18.2
25.0
15.1 13.2
10.0
11.0
14.0
24.5
27.1
16.9
13.6
18.0
22.0
10.4
17.0 5.7
1.4
1.9
1.9
37.7
10.1
4.8
6.8
1.6
22.0
6.3
13.2 79.2
90.0
91.3
82.6
54.7
67.8
27.8
52.5
65.6
37.1
83.3
37.7 20.8
8.6
7.7
11.6
41.5
28.8
28.8
39.0
34.4
34.6
14.6
41.5 --
1.4
1.0
2.9
3.8
3.4
20.0
8.5
--
17.0
--
13.2 --
--
--
2.0
--
--
23.4
--
--
13.3
2.1
7.6
Average 57.8 19.5 15.0 7.7 62.9 23.8 7.2 6.1
Source : Vyas et al. (1993)
On an average 35.5 percent water samples had none of the problem and hence, were of good quality. The range of good quality water in different tehsils, however , varies from 7.4 per cent in Sambher to 65.2 percent in Amber tehsil. In Viratnagar, Amber, Jamva Ramgarh and Jaipur tehsils, percentage of good quality water was above 50. In Kotputali and Chaksu it was about 37.7 percent and it was low in Bassi, Sanganer, Phagi and Dudu tehsils and was lowest in Sambhar tehsil (Table2.17).
In general there was less problem of salinity and sodicity alone. The results showed that there was problem of RSC, which was as high as 69.8 percent in water samples of Sanganer followed by Sambhar (58.0%) and Bassi (54.2%) tehsils. In other tehsils it was in the narrow range of 33 to 42 percent. There was both salinity and sodicity problem in Dudu tehsil (42.6%) (Table 2.17 ).
There was a severe problem (> 50%) of soil alkalinity in Viratnagar (72.9%) and Phagi (64.9%) tehsils, moderate (25 to 50%) problem in Sambhar (46.7%), Jaipur (36.1%), Dudu (36.0%) and Chaksu (32.8%) tehsils and slight problem in Bassi (23.7%), Amber (20.3%), Dausa (18.7%), Kotputali (11.3%) and Jamva Ramgarh (10.4%) tehsils. Severe problem of soil salinity was observed in Phagi (61.4%) tehsil while it was moderate in Dudu (32.6%) tehsil and slight in Tehsils of Chaksu (24.6%), Sambhar (16.6%), Bassi (15.3%) and Dausa (14.6%). (Table 2.18)
Table 2.17: Classification of irrigation waters of different tehsils of Jaipur District

Water quality Kotputali
(53)** Virat nagar
(70) Amber
(207) Jaipur
(107) Sanganer
(53) Bassi
(59)
Good
Marginally saline
Saline
Saline sodic
E1 RSC water
E2 RSC water 37.7
9.4
3.8
9.4
13.2
26.4 61.4
4.3
0.0
1.4
27.1
5.7 65.2
0.5
0.0
0.5
26.1
7.7 52.3
0.0
0.0
4.7
33.6
9.3 22.6
1.0
0.0
5.7
30.2
39.6 30.5
1.7
3.4
10.2
32.2
22.0

Water quality Dudu Phagi Chaksu Sambhar J.Ramgarh Dausa Mean
(209) (59) (61) (162) (48) (53)
Good
Marginally saline
Saline
Saline sodic
E1 RSC water
E2 RSC water 11.0
10.5
0.5
42.6
17.2
18.2 22.0
13.6
5.1
17.0
16.9
25.4 37.7
13.1
3.3
8.2
16.4
21.3 7.4
5.5
1.9
27.2
22.2
35.8 54.2
0.0
0.0
4.2
29.1
12.5 24.5
5.7
0.0
22.6
7.6
39.6 35.5
5.4
1.6
12.8
22.6
22.0
Source : Vyas et al. (1993) ** Number of samples tested.
Table 2.18 : Classification of soils of different Tehsils of Jaipur Districts based on pH and EC
Characteristics Kotputali Virat Nagar Bassi Chaksu Jamva Ramgarh Dausa
pH < 8.5
> 8.5
EC < 4.0
> 4.0 88.7
11.3
94.3
5.7 27.1
72.9
97.1
2.9 76.3
23.7
84.8
15.3 67.2
32.8
75.4
24.6 89.6
10.4
97.9
2.1 81.3
18.7
85.4
14.6
Sambhar Dudu Amber Phagi Sanganer Jaipur
pH < 8.5
> 8.5
EC < 4.0
> 4.0 53.3
46.7
83.4
16.6 64.0
36.0
68.4
32.6 79.7
20.3
98.6
1.4 35.1
64.9
38.6
61.4 90.6
8.4
92.4
7.5 3.9
36.1
96.4
4.6
(Vyas et al, 1993)








Bikaner district :
Survey of underground waters of non-command area of Nokha, Kolayat, Loonkaransar and Bikaner tehsils of Bikaner District revealed that water table of tubewells varied from 36 to 208 m. EC and pH of tubewell waters varied from 0.8 to 10.3 dSm-1 and 7.1 to 9.0, respectively. The RSC were < 2.5, 2.5 to 5.0 and >5.0 mel-1 in 81.3, 16.3 and 2.4 percent of water samples , respectively. On an average 32.6, 16.3, 17.4, 12.8, 4.1, 9.3, 4.1 and 3.4 per cent samples were categorized as good, marginally saline, high-SAR saline, high-SAR non-saline, saline, marginally alkali, alkali and highly alkali, respectively. About 11.1, 42.9, 29.7 and 16.3 percent of the samples had salinity <1.0, 1-2, 2-4 and >4.0 dSm-1, respectively (Lal et al.1998). The waters are mostly Na-Mg-Ca type with dominance of chloride followed by carbonates + bicarbonates (Table 2.19 & 2.20). Water quality map of Bikaner is depicted in Fig.5



Analysis of surface soil samples collected from the fields irrigated with corresponding water revealed that EC2 of all the soil samples is < 1 dSm-1 and soil is alkaline in nature. Correlation studies revealed that EC of soil is positively and significantly correlated with ECiw (r=0.411**) and potential salinity of irrigation water (r=0.465**). Correlation between SARiw and SAR of soil was found positive (r=0.206) but non-significant. It might be due to the fact that most of the wells are operating since 1992 and onwards only.
Table 2.19: Range of chemical characteristics of tube well/ well waters in Bikaner District

Chemical Characteristics Tehsils of Bikaner
Bikaner District as a whole
Nokha Kolayat Loonkaransar Bikaner
pH
EC (dSm-1)
CO3-2 + HCO3-1(mel-1)
Cl-1 (mel-1)
SO4-2 ( ” )
Ca++ ( ” )
Mg++ ( ” )
Na+ ( ” )
K+ ( ” )
RSC ( ” )
SAR
Adj. SAR
SSP 7.1-8.8
1.0-6.1
2.5-12.5
2.0-55.8
0-7.0
0.4-14.7
0.9-12.8
7.6-37.6
0.03-1.03
Nil-8.1
3.3-22.4
8.4-43.9
28.0-91.3 7.5-8.8
0.8-10.3
2.5-8.4
1.6-101.0
0.1-10.8
0.5-7.5
0.9-18.9
6.6-78.2
0.1-0.6
Nil-5.8
4.7-30.8
7.9-58.2
47.9-90.2 7.6-8.7
2.3-7.9
3.0-5.8
18.6-55.2
--
1.4-8.6
2.9-7.2
21.5-84.0
0.1-0.4
Nil-4.2
12.9-27.4
25.8-68.8
78.6-88.9 8.0-9.9
0.8-7.7
1.6-7.8
3.7-44.2
Nil-31.9
0.3-3.8
0.4-11.8
5.6-65.5
0.1-0.2
Nil-4.8
5.3-41.8
9.3-73.2
60.1-95.1 7.1-9.0
0.8-10.3
1.6-12.5
1.6-101.0
Nil-31.9
0.3-14.7
0.4-18.9
5.6-84.0
0.03-0.6
Nil-8.1
3.3-41.8
7.9-73.2
28.0-95.1


Table 2.20 : Percentage distribution of water samples in different ranges of EC and RSC

RSC
(mel-1) EC (dSm-1)
<1 1 - 2 2 - 3 3 – 4 > 4 Total
1 2 3 4 5 6 7
Nokha Tehsil
< 2.5
2.5 – 5.0
5.0 – 7.5
> 7.5 --
--
--
-- 48.4
9.7
--
1.6 17.7
1.6
1.6
-- 11.3
--
--
1.6 6.5
--
--
-- 83.9
11.3
1.6
3.2
Kolayat Tehsil
< 2.5
2.5 – 5.0
5.0 – 7.5 3.0
3.0
3.0 27.3
18.2
-- 12.1
--
-- 12.1
--
-- 21.2
--
-- 75.7
21.2
3.0
1 2 3 4 5 6 7
Loonkaransar Tehsil
< 2.5 -- -- 33.3 46.7 20.0 100.0
Bikaner Tehsil
< 2.5
2.5 – 5.0 24.2
1.6 19.4
16.1 11.3
1.6 3.2
-- 19.4
3.2 77.5
22.5
Bikaner District as whole
< 2.5
2.5 – 5.0
5.0 – 7.5
> 7.5 9.3
1.2
0.6
-- 29.6
12.7
--
0.6 15.7
1.2
0.6
-- 11.6
--
--
0.6 15.1
1.2
--
-- 81.3
16.3
1.2
1.2
11.1 42.9 17.5 12.2 16.3 100.0


Churu Distrist:
Verma et al. (2003) reported that in Churu district EC of water samples ranged between 0.4 to19.7 dSm-1 (Table 2.21) About 32 per cent water samples have EC <2.0 dSm-1 while EC of 36 per cent samples fell between 2.0-4.0 dSm-1. Based upon EC it can be stated that Sri Dungargarh tehsil is underlain with relatively better quality waters followed by Sujangarh, whereas , water of North- Eastern tehsils viz. Churu, Taranagar, Rajgarh and Sardarshahar are of marginal quality. pH of water samples ranged between 7.2 to 9.3. pH of more than 57 per cent water samples ranged between 8.1 to 8.5 while only 3.0 per cent samples have pH less than 7.5. Tehsils of Northern part of district Viz; Sardarshahar ,Taranagar and Rajgarh have waters of high pH (>8.5), as compared with others . RSC of water varied between nil to 13.1 mel-1 . About 75 per cent water samples recorded RSC <2.5 mel-1 whereas, about 9 and 16 per cent water samples had RSC between 2.5 to 5.0 and >5.0 mel-1, respectively. Tube wells are relatively shallow (<50 m) in Eastern part of district i.e. Taranagar, Rajgarh and Chruru tehsils, whereas, tubewells are deeper in Sri Dungargarh , Sardarshahar and Sujangarh. Aquifer depth from tube wells draw water varied from 7 to175 m.Mg/ Ca ratio >3.0 was in ground waters of north-eastern tehsils of Churu district Viz. Sardarshahar , Churu ,Taranagar and Rajgarh tehsils , while, it was between 1.0-2.0 in more than 75 per cent samples of Sri Dungargarh and Ratangarh tehsils .The quality of under ground waters of Churu, Taranagar, Rajgarh and Sardar Shahar tehsils of Churu district is poor. On an average 26.6 per cent samples fell under the category good, whereas, 15.3, 4.9, 28.7, 4.3 and 20.0 per cent samples were under marginally saline, saline, high SAR saline, marginally alkali and high alkali, respectively (Table 2.22). Water quality map of Churu is depicted in Fig.6







Table 2.21: Range of chemical characteristics of tube wells / open wells
water of Churu district
Chemical
Characteristics Sri
Dungar Garh
(87)* Sardar
Shahar

(93) Sujan
garh

(101) Ratan
garh

(67) Churu


(61) Taranagar


(23) Rajgarh


(124) Churu district
pH 7.8-9.2 8.0-9.1 7.8-8.7 7.6-8.7 7.3-8.4 8.1-9.2 7.9-9.3 7.3-9.3
EC (dS m-1) 0.4-4.1 0.6-8.6 0.8-11.6 1.1-4.8 2.1-1.4 1.9-19.7 1.7-18.2 0.4-19.7
RSC (me l-1) Nil-7.8 Nil-11.4 Nil-4.3 Nil-10.0 Nil-13.1 Nil-9.3 Nil-12.8 Nil-13.1
SAR 1.0-17.7 2.2-31.4 1.7-21.7 3.4-1.5 6.9-7.7 6.2-33.5 8.4-27.9 2.2-33.5
Adj . SAR 2.2-49.6 4.2-74.0 3.8-62.9 7.5-3.3 18.9-77.3 16.0-80.4 19.2-14.6 2.2-14.6
SSP 23.0-87.5 43.7-95.1 31.6-84.8 49.0-91.7 16.0-90.9 46.6-93.2 46.4-1.0 16.0-3.2
Mg/Ca 0.5-3.3 1.0-7.5 0.6-4.6 0.4-3.3 1.1-6.2 1.1-6.6 1.0-11.0 0.4-11.0
Water table (m) 35-152 40-87 20-175 38-133 23-50 7-37 10-61 7-175
Soil
pH 8.2-9.1 8.6-10.2 7.7-9.3 8.5-9.9 8.2-9.8 7.9-8.5 7.8-10.4 7.7-10.4
EC (dSm-1) 0.1-0.6 0.1-0.8 0.1-1.9 0.2-1.2 0.3-2.3 0.7-1.9 0.4-2.3 0.1-2.3
SAR 0.3-2.9 0.7-4.3 0.5-20.0 1.4-2.1 1.6-9.2 3.0-26.0 2.4-19.6 0.3-26.0
Source : Verma et al. (2003) *Figure in Parenthesis indicate number of sample tested

Table 2.22: Percent distribution of water samples under different
categories of water quality in Churu district.
Water quality Sri
Dunga
garh Sardar
Shahar Sujan
garh RatanGarh Churu Taranagar Rajgarh Churu district
Good 72.4 11.8 49.5 32.9 -- -- 1.6 26.6
Marginally saline 11.5 5.4 31.7 26.9 6.6 -- 12.9 15.3
Saline 1.1 3.2 6.9 1.5 9.8 4.4 6.5 4.9
High SAR Saline 6.9 33.3 9.7 3.0 62.3 73.9 45.2 28.7
Marginally Alkali 3.4 7.5 2.0 11.9 -- -- 3.2 4.3
Alkali -- 1.1 -- -- -- -- -- 0.2
High Alkali 4.6 37.6 -- 23.8 21.3 21.7 30.6 20.0
Nagaur district:
Survey and characterization of underground waters of five tehsils (Nagaur, Jayal, Ladnu , Kheenwsar and Merta ) of Nagaur district revealed that EC and pH of water samples ranged between 0.61 to 11.9 dSm-1 and 7.0 to 9.3,respectively (Table 2.23). RSC of water varied between nil to 14.1 mel-1. As regards salinity 2.3, 16.0, 41.3 and 40.2 percent water samples showed EC < 1.0, 1.0 - 2.0, 2.0 - 4.0 and > 4.0 dSm-1, respectively in Nagaur tehsil. In Jayal tehsil 59.2 per cent water samples showed EC > 4.0 dSm-1. In Jayal, Ladnu, Kheenwsar and Merta tehsils about 59.2, 33.9, 22.9 and 32.6 percent water samples showed EC > 4.0 dSm-1, respectively (Table 2.29).On an average 10.6, 11.8, 4.7, 36.5, 3.5 and 32.9 percent water samples were under good, marginally saline, saline, high SAR saline, marginally alkali and high alkali categories, respectively in Nagaur tehsil, whereas in Jayal tehsil, about 10.2,15.3, 8.4, 47.3, 8.4 and10.2 percent water samples were under good, marginally saline, saline, high SAR saline, marginally alkali and high alkali categories, respectively. In Ladnu tehsil on an average 18.6, 40.7, 1.7, 33.9 and 5.1 per cent water samples were under good, marginally saline, saline, high SAR saline and high alkali categories, respectively, whereas in Kheenwsar tehsil 28.3, 45.8 and 25.7 percent samples were under good , marginally saline and high SAR saline, respectively. In Merta tehsil about 34.1, 26.1 13.0, 26.1 and 0.7 per cent water samples fell under good, marginally saline, saline, high SAR saline and marginally alkali categories, respectively(Table 2.24). About 35.5 ,18.6 and 6.8 percent water samples had RSC > 2.5 mel¬-1 in Nagaur, Jayal and Ladnu tehsils, respectively whereas kheenwsar and Merta tehsils are free from RSC problem. Fluoride and Nitrate contents in under ground irrigation waters of these tehsils ranged between nil to 16.5 and 0.2 to 148.4 mgl-1, respectively. The waters were Na:Mg:Ca type dominated with chloride anion. Range of chemical characteristics of soil under tube well / open well irrigation water in different tehsils of Nagaur district are presented in table 2.25.
Table2.23: Range of chemical characteristics of tube wells / open wells water of Nagaur district
Chemical
Characteristics Nagaur
85* Jayal
59 Ladnu
59 Kheenwasar
70 Merta
138 Range
411
pH 7.8-9.2
(8.18) 7.9-9.1 (8.36) 7.0-8.6 (7.68) 7.2-8.7
(8.08) 7.31-9.3 (8.00) 7.0-9.3 (8.06)
EC
(dSm-1 ) 0.9-9.5
( 3.70) 0.7-1.9
(4.92) 1.2-7.6 (3.49) 0.61-6.2(0 (2.74) 0.77-7.54 (2.90) 0.61-11.9
(3.41)
RSC
(mel-1 ) Nil - 14.1 Nil - 9.6 Nil-10.8 Nil-2.1 Nil-3.3 Nil-14.1
SAR 2.6 - 34.7 2.2 - 48.6 3.5-48..2 2.1-25.5 1.3-28.7 1.3-48.6
Adj . SAR 4.6 - 72.5 4.0 - 102.1 9.8-90.0 4.0-53.9 3.0-67.2 3.0-102.1
SSP 36.3 -94.0 32.6 - 95.0 36.1-94.9 38.9-88.6 21.4-91.3 21.4-95.0
Mg/Ca 0.6 - 4.9
(2.07) 0.7-4.5 (2.73) 0.6-5.7(2.85) 0.7- 4.0
(1.78) 1.0-8.6 (3.00) 0.6-8.6
(2.54)
Nitrate
(mg l-1) 0.3-19.3 1.2 - 56.0 0.4-66.8 2.0-62.0 0.2-148.4 0.2-148.4
Fluoride
(mg l-1) Nil - 11.8 Nil - 12.0 0.5 - 16.5 0.7 -4.0 0.1-9.1 Nil-16.5
Water table (m) 32.7-134.0 30.0 - 100.0 40.0-133.3 53.3-153.3 16.3-150.0 30.0-153.3

Source : Verma et al. (2005) *Number of sample tested Figure in Parenthesis are the average value
Table 2.24: Distribution (percent) of water samples in different ranges of EC and RSC in Nagaur district
RSC (mel-1 ) EC (dSm-1 )
<1 1-2 2-3 3-4 >4 Total
Nagaur Tehsil
<2.5 2.3 8.0 3.4 13.8 36.8 64.3
2.5-5.0 - 3.4 2.3 2.3 - 8.0
5.0-7.5 - 4.6 8.1 3.4 2.3 18.4
> 7.5 - - 3.4 4.6 1.1 9.1
Jayal Tehsil
<2.5 3.4 6.8 13.6 6.8 50.8 81.4
2.5-5.0 - 3.4 3.4 - 8.4 15.2
5.0-7.5 - - - 1.7 - 1.7
> 7.5 - - 1.7 - - 1.7
Ladnu Tehsil
<2.5 - 20.3 35.6 8.5 28.8 93.2
2.5-5.0 - - - - 1.7 1.7
5.0-7.5 - - - 1.7 1.7 3.4
> 7.5 - - - - 1.7 1.7
Kheenwasar Tehsil
<2.5 17.1 12.9 32.9 14.2 22.9 100.0
Merta tehsil
<2.5 2.9 31.9 16.7 15.2 32.6 99.3
2.5-5.0 - - - 0.7 - 0.7

Table 2.25: Percent distribution of water samples under different categories of water quality in Nagaur district.
Water quality categories Tehsils
Nagaur Jayal Ladnu Kheenwasar
Merta
Good 10.6 10.2 18.6 28.5 34.1
Marginally saline 11.8 15.3 40.7 45.8 26.1
Saline 4.7 8.4 1.7 - 13.0
High SAR Saline 36.5 47.3 33.9 25.7 26.1
Marginally Alkali 3.5 8.4 - - 0.7
Alkali - - - - -
High Alkali 32.9 10.2 5.1 - -

Table 2.26: Range of chemical characteristics of soil under tube well / open well irrigation water in different tehsils of Nagaur district
Chemical
Characteristics Tehsil
Nagaur
78* Jayal
46 Ladnu
43 Kheenwasar
53 Merta
138
pH 7.8-10.0 (8.91) 8.4-10.0 (9.07)** 8.5-9.7 (9.02) 7.3-9.6 (8.79) 7.2 -10.4 (8.81)
EC (dSm-1) 0.2 - 3.1 (0.87) 0.18-4.68 (1.05) 0.16-1.37 (0.44) 0.18 - 4.26 0.19-3.36 (0.66)
Ca (mel-1) 0.4 - 7.8 0.3 - 9.0 0.4 -1.3 0.3 -10.1 0.3 - 7.6
Mg (mel-1) 0.3 - 6.8 0.5 - 8.8 0.4 -1.4 0.3 -11.6 0.4 - 11.0
Na (mel-1) 1.0 – 29.0 1.1 - 21.8 0.8 -12.2 0.7 -17.0 1.1 - 28.9
K (mel-1) 0.1 - 0.5 0.04 - 0.99 0.04 - 0.38 0.02 - 0.28 0.03 -1.0
CO3- -+HCO3- (mel-1) 0.9 - 8.3 0.6 - 3.6 0.9 - 2.2 0.6 - 2.5 0.6 - 7.9
Cl - (mel-1) 0.7 – 29.7 0.9 - 44.0 0.7 -10.8 0.8 - 26.0 0.6 - 30.4
SO 4- - (mel-1) 0.2 - 3.4 0.2 - 8.7 0.19 - 3.35 0.13 - 4.28 0.15 - 3.71
SAR 1.2- 28.8 1.6 - 19.8 1.0 - 13.5 0.8 - 10.5 0.7 - 18.4
* Number of samples tested **Figures in parenthesis are the average values
Salinity levels:
It has been reported that in areas in the north-eastern and southern parts of Rajasthan (Jaipur, Kota and Udhaipur where rainfall > 500mm), the ground waters have residual alkalinity in significant amounts. Ground waters of Nagaur, Sikar and Jhunjhunnu districts also have high residual alkalinity. Salinity of ground waters in shallow aquifers of eastern Rajasthan is generally <2 dSm-1. Ground water salinity increases towards north and north-east Rajasthan. Over 4 dSm-1 of ground water salinity is found in major parts of eastern Rajasthan, namely Bharatpur, Tonk, Sawai Madhopur and Ajmer districts . Phreatic ground water with EC more than 8 dSm-1 was analysed in major portions of Barmer and Jaisalmer districts except western, central and south central parts where ground water is fresh and potable; western half of Bikaner district and major parts of Ganganagar district except along Gaggar flood plains.In south-eastern, northern and north- eastern parts of Churu district salinity is above 8 dSm-1. Saline ground water with EC>8 dSm-1 is common in Nagaur district,central parts of Bharatpur district and in very small pockets in the vicinity of Sambhar lake in Jaipur and Ajmer districts. Salinity levels in shallow ground water varies widely from good to as much as 47 dSm-1. In respect of western districts the upper limit of salinity in ground water ranges upto 47 dSm-1 , whereas, in the eastern districts it is upto 13 dSm-1 . In a localized area around Sitapur and Todara in Sawai Madhopur district salinity is around 21 dSm-1. Brine deposits with salinity (TDS >240000 ppm) in saltlake depression area around Pachpadra (Barmer district), Phalodi (Jodhpur district), Sambhar lake ( Jaipur district) , Didwana ( Nagaur district) and in depression areas of Bharatpur district is unique. In deeper aquifers the upper limit of salinity reaches as high as 58 dSm-1 in Barmer district, 23 dSm-1 in Bharatpur district and 47 dSm-1 in Pali district.
Fluoride:
Fluoride occurs in ground waters in all the districts of Rajasthan, irrespective of salinity . Somani et al. (1972) reported that well water from Nagaur and Jaipur district contained 4.5 and 28.1 mgl-1 fluorine with a mean value of 5.5 mgl-1. Further, in Udaipur district Somani (1974) found a mean value of 4.8 mgl-1 with a range of 0.18 to 21.6 mgl-1 fluorine. Positive correlation was found between fluorine with depth of water table and sodium content of water (Somani, 1974; Singh and Sisinwar ,1975). Sinsinwar et. al.(1981) reported that fluoride content in well waters of Srigagangar district ranged from 0.10 to 28.2 mgl-1. Gupta (1986) observed 40 per cent water samples in Pali and Jalore districts containing fluoride concentration above the permissible limit of 2.0 mel-1. Singh and Anand (1991) reported that ground water of Jhunjhunu district is suitable for drinking purpose but at some locations fluoride content exceeds 30 mgl-1. Ozha and Sharma (1993) while making investigation of 1870 water samples from Nagaur, Barmer and Jalore districts of western Rajasthan found that more than 50 per cent water samples had fluoride concentration > 1.5 mgl-1 and the problem was more acute in Nagaur district.They noted 34 mgl-1 fluoride in these waters . The problem of high fluoride was equally serious in southern -eastern part of state as Gupta et al. (1983) noted 10 to 20 per cent water samples in Banswara, Bundi, Rajsamand and Udaipur and more than 25 per cent samples of ground waters of Ajmer, Bhilwara, Dungarpur and Kota districts had > 1.5 mgl-1 fluoride. The situation found to be most grim in Bhilwara and Ajmer districts where 47.6 and 63 per cent water samples, respectively showed this condition. Highest 16.2 mgl-1fluoride was noted in Ajmer by them in their study. Baran, Chittorgarh and Jhalawar districts presented better picture with respect to fluoride where more than 90 per cent water samples were found to be in safe limit. In arid and semi arid regions of Rajasthan the percentage of waters having fluoride higher than 10.0 mg L-1, is very small(< 5) and the highest concentration is 30 mg l-1 except Nagaur district, where it occurs up to 90.0 mg L-1 ( Anonymous, 2000 ;Table 2.27).Bagoria (2002) reported that fluoride content of Nagaur tehsils ranged between 0.10 to 11.0 mg L-1 and about 20 percent water samples were found to have fluoride content within permissible limit as per W.H.O.

Table 2.27: Percentage wise distribution of fluoride (mgl-1 ) in ground waters of Rajasthan.
District No. of Samples Fluoride (mgl-1 )
<5 5-10 >10 Max
Barmer 537 73.1 9.1 2.8 19.6
Bikaner 144 91.9 7.6 1.4 12.0
Churu 316 92.1 6.6 1.3 30.0
Jaisalmer 268 97.4 2.6 - 5.0
Jalore 165 92.3 9.1 0.6 14.2
Jodhpur 704 89.9 9.1 1.0 22.0
Nagaur 1080 83.9 11.4 4.7 90.0
Pali 236 89.4 8.5 2.1 18.3
Ganganagarh &Hanumangarh 84 97.6 1.2 1.2 26.0
Sikar 314 95.6 4.4 - 15.0
Sirohi 597 98.5 1.5 - 11.0
Jhunjhunu 295 95.0 5.0 - 12.0
Jaipure 120 - - - 28.1
Bhilwara - - - - 24.0
Udaipur 166 - - - 21.5
Bharatpur 100 - - - 21.5
Tonk - - - - 18.4
Alwar - - - - 7.6
Source: Anonymous,2000


Nitrate:
In Barmer, Jaisalmer and Bikaner districts about 45, 18 and 25 percent water samples were in the range of < 20, 20-50 and 50-100 mgl-1 nitrate, respectively (Gopal et. al. 1983; Table 2.28). Singh and Anand (1991) reported that ground water of Jhunjhunu district is suitable for drinking purpose but at some location nitrate content exceeds 100mgl-1.Ozha and Jain (1992) noted greatest frequency of water having nitrate above 100 mgl-1in Churu district (76.0%) followed by Nagaur (53.7%),Barmer (53.7%) and Jalore (41.0% ) district. Lower frequency (3.04%) of such water was recorded in Bikaner district. In an another study of Ozha and Sharma (1993) in Churu district maximum nitrate level was recorded as 2400 mgl-1and only 14.2 per cent of water samples contained nitrate up to 50 mgl-1. In Barmer district the maximum recorded Nitrate value was 1900 mgl-1 and 32 per cent samples contained nitrate up to 50 mgl-1. Rai and Gulati (1997) reported a range of 15 to 590 mgl- 1 nitrate in 60 well water samples of Jodhpur. They recorded the nitrate levels in 55 out of 60 wells beyond maximum permissible limit.About 75% water samples having nitrate >100 mgl-1 was reported in Churu district (Anonymous,2000 ; Table 2.29)
Table 2.28: Distribution percent of nitrate in ground water of some districts of western Rajasthan
NO3 (mgl-1) Barmer Jaisalmer Bikaner Average
<20 18 50 66 45
20-50 8 19 27 18
50-100 63 22 2 25
Source: Gopal et al. (1983)

Table 2.29: Percentage wise distribution of nitrates (mgl-1 ) in waters of Rajasthan.

Climatic zone
District Nitrate (mgl-1)
Max. <50 50-100 >100
1 2 3 4 5 6
Arid * Barmer 1600 32.0 13.2 54.8
Bikaner 2100 47.0 16.7 36.2
Sriganganagar 533 72.0 13.9 13.9
Hanumangarh 780 56.0 20.0 24.0
Jaisalmer 1400 62.7 10.4 26.8
Jodhpur 2800 41.0 21.0 37.9
Arid-cum semi-arid * Churu 2350 16.2 8.2 75.7
Jalore 600 56.4 10.9 32.7
Jhunjhunu 544 51.8 23.4 24.6
Nagaur 4750 31.0 16.8 52.1
Pali 1400 71.6 16.1 12.2
Sikar 748 47.4 24.0 28.6




1



2



3



4



5



6
Semi-arid** Ajmer 730 57.4 20.9 22.1
Alwar 1350 30 30 40
Bharatpur 825 70 ----------30----------
Bhilwara 1010 65 16 19
Dausa 780 - - -
Dhaulpur 300 2 - -
Jaipure 2640 37 42 21
Karauli 460 - - -
Sawaimadhopur 1100 - - -
Tonk 1050 72 12.3 15.8
Sub-humid ** Bundi 395 92.2 - 7.8
Chittaurgarh 270 - - -
Rajsamand 370 ---- -89 ------------ 11
Sirohi 395 8 9.3 10.7
Udaipur 472 68.7 21.3 10.0
Humid** Banswara 206 83 7.4 3
Baran 370 89.3 6.1 4.6
Dungarpur 408 87.2 4.3 8.5
Jhalawar 397 83 10 7.0
Kota 650 83.4 11.0 5.7
Source: Gupta (2000)*; SRSAC &7 GWD (1999)**

Boron:
In Rajasthan Boron in irrigation waters is quite high and ranges from traces to as high as 5 mgl-1 in some well waters of Nagaur, Jaipur, Sirohi, Jodhpur, Bhilwara and Pali districts. Mandal (1967) reported that boron content of different kinds of underground water used for irrigation in Rajasthan varied from 0.28 to 7.66 mg l-1 Examination of boron content of 452 ground water samples from several districts of Rajasthan reveal the content lesser than 3 mgl-1 (Paliwal, 1972). However, 10.7 mgl-1 boron has been reported in ground water of Bikaner district having EC 15.0 dSm-1 (Gajbhiye et al. 1973). Boron content of well waters of Rajasthan as reported by different workers is given in table 2.30.
Table 2.30 : Boron content of well waters of Rajasthan
District No. of samples Range (mgl-1) Av. (mgl-1) Authors
Nagaur 74 0.05-3.1 1.28 Paliwal & Gandhi,1969
Bhilwara 59 0.13-1.62 0.75 Paliwal & Maliwal,1966
Pali 19 0.62-3.1 1.28 Paliwal & Maliwal,1966
Jodhpur 11 0.62-2.18 1.32 Paliwal & Maliwal,1966
Jalour 110 0.50-5.0 1.33 Anonymous,1964
Kota 65 0.10-3.0 0.95 Mathur et al. 1969
Jaipur 85 Tr.-6.0 1.80 Paliwal & Maliwal,1966
Bikaner 137 0.22-10.7 - Gajbhiye et al . 1973
Bharatpur 100 Tr.- 4.4 - Gupta. 1979
Udaipur 166 0.05-4.1 0.4 Gupta. 1979

Lithium :
Gupta and Sanganeria (1979) analysed 126 ground water samples from Udaipur district in Rajasthan. Lithium content varied from 0-0.39 mgl-1 with an average value of 0.05 mgl-1 in waters having EC 0.34 to 9.2 dSm-1. Lithium content increased with increase in salinity.The percentage of water samples having lithium <0.05 and 0.05 to 0.5 mgl-1 was 34 and 46, respectively
Other trace elements:
Gupta and Sanganeria (1979) determined the trace elements in ground water of Udaipur district having EC 0.34 to 9.2 dSm-1 which are presented in Table 2.31
Table 2.31: Trace elements in ground water of Udaipur district (mgl-1 )
Elements Min. Max. Average
Cu 0 0.19 0.019
Fe 0 3.00 0.41
Mn 0 2.05 0.074
Zn 0.06 1.25 0.147
Source : Gupta and Sanganeria (1979)

Ground water quality in IGNP:
The chemical quality of ground water is largely saline except along Ghaggar plains. The EC of ground water ranges between 0.48 to 39.6 dSm-1. Chemical quality along Ghaggar plains in upper horizon ( up to a depth of 25 to 30m) was observed to be fresh. It is evident from the data (Table 2.32) that a fresh cushion is developed over the saline native ground water mainly due to continuous recharge from different sources. The exploitable fresh ground water zones are mainly restricted in Ghaggar bed in the proximity of main canal and distributory systems.
Table 2.32: Changes in chemical quality in IGNP Phase I:
Site 1993-94 1994-95 95-96 96-97 98-99 1999-2k 2k-01 01-02 02-03
EC * pH EC pH EC EC EC EC pH EC EC EC
Anupgarh 0.86 7.5 0.79 9.9 0.68 0.78 0.85 0.65 8.1 0.61 0.70 0.80
Ramsingh pur 1.45 9.8 1.70 8.8 1.58 1.05 1.20 1.20 8.1 1.14 1.23 1.10
Sangeeta 1.30 8.5 1.38 8.6 1.40 1.44 1.60 1.68 8.1 1.36 1.47 1.71
Manaksar 0.56 9.0 0.64 8.4 0.70 0.48 0.60 0.61 8.1 0.61 0.63 0.64
Rangmahal 9.65 8.4 12.2 8.8 8.20 8.50 12.35 11.8 7.9 10.6 10.0 8.80
Badopal 0.74 7.8 0.63 8.7 0.99 1.00 2.00 0.87 8.0 1.14 1.01 1.15
Bherusari 1.60 8.5 1.40 8.8 1.23 0.80 2.55 0.72 8.0 0.82 1.30 1.23
Khetawali 1.87 9.0 2.04 8.1 2.08 1.95 0.80 2.10 8.0 1.91 1.65 1.81
Dubali Khurd 0.98 8.3 1.40 8.5 0.99 0.85 38.0 1.15 7.9 0.73 1.46 0.89
29DWD - - 33.6 7.1 - 14.0 9.80 39.5 9.8 41.8 41.3 30.6
Basir 7.00 8.7 8.36 8.6 8.00 7.8 6.20 6.93 8.1 9.6 8.87 7.39
Lakhuwali 7.60 9.3 6.20 8.6 6.00 6.10 - 6.00 7.8 6.07 6.13 6.13
Manaktheri 0.96 9.0 0.84 9.0 - 0.70 - - - 1.61 1.58 1.55
Source : Annual Report, CAD (2003-04) * EC is expressed in dSm-1
Data on changes in chemical quality of ground water in IGNP Phase II (Table 2.33) indicated that in general native ground water is saline having EC about 10.0 dSm-1. However chemical quality in the vicinity of canals is better with EC values of 3.0 dSm-1, which shows that fresh water horizon , is developing gradually. This fresh water cushion has a significant thickness at places , which can be attributed to the percolation , seepage of water from irrigation network developed in the area.
Table 2.33: Changes in chemical quality in IGNP Phase II
Site 1993-94 1995-96 96-97 97-98 98-99 99-2k 2k-01 01-02 02-03
EC pH EC pH EC EC EC pH EC EC EC EC
ManaksarDy.RD 100 0.9 7.7 1.05 8.5 0.73 0.55 0.60 7.9 0.99 1.41 1.35 1.39
Chakosa 10.15 7.1 9.00 7.7 9.40 8.28 9.81 8.0 10.6 10.3 9.6 9.83
Ramai 10.57 7.5 10.50 8.0 9.80 9.00 8.90 8.1 10.0 10.3 10.1 10.3
Adhuri head 0.74 8.2 0.92 8.9 0.70 0.84 0.80 8.2 4.48 4.36 4.41 4.79
Adhuri village 6.70 8.0 3.30 8.5 3.00 2.95 3.60 8.0 4.48 4.36 4.41 4.48
Makheri 12.90 7.9 14.40 7.8 14.7 11.0 13.90 7.9 13.0 14.0 13.8 13.7
IGN 1381 RD 0.55 8.8 0.93 7.9 0.91 0.45 0.30 8.0 0.64 0.59 0.61 0.65
Tanwarwala 15.00 7.8 15.30 8.1 15.6 12.1 15.90 8.1 16.3 16.5 16.4 16.5
IGN 1458RD 0.52 8.9 0.70 8.5 0.94 0.68 0.51 8.2 0.56 0.80 0.82 0.71
Deli Talai 2.53 8.5 1.68 8.6 2.88 1.75 1.95 8.0 1.71 1.76 1.87 1.91
Jaggasar 1.56 8.2 0.94 8.6 1.35 1.51 0.90 7.9 0.74 0.83 0.83 0.85
Cholewali Dy.R D10 2.61 7.6 3.70 9.2 0.54 0.51 0.58 8.0 0.56 0.61 0.63 0.68
SBS 17 RD - - - 7.60 7.25 6.70 8.0 8.80 8.50 8.70 8.78
JJW 53 RD - - - - 7.80 1.31 3.00 8.2 5.90 6.35 6.55 9.01
TuliDy.00RD8. - - - 12.9 13.9 13.70 8.1 12.5 6.74 6.78 14.7
Sadhan Dy. 165 RD - - - 9.30 13.9 18.8 8.0 17.4 18.0 18.2 18.4
SMG 90 RD - - - - 23.9 26.6 29.2 8.1 28.9 29.0 29.3 29.4
Nedai - - - - 13.2 34.1 22.9 8.1 23.4 23.9 24.6 24.7
Arjana - - - - 8.70 8.80 9.0 8.2 8.2 7.74 7.50 7.45
Source : Annual Report, CAD (2003-04) * EC is expressed in dSm-1
Dogne (1995) studied soils of Kanwar Sen Lift Canal area of IGNP, and classified into different categories, based on the USDA classification. Out of 50 chacks, 29 chacks had sodic soils, 7 chacks saline sodic, 11 chacks saline soils and 3 chacks had both saline and saline sodic soils. Prakash (2001) reported that the salt accumulations were found more in sub surface soils as compared to surface soils. On the basis of salinity and alkalinity indices, the surface and sub surface soils have moderate salinity and slightly alkalinity problems in the soils of Kanwar Sen Lift Canal area of IGNP, Bikaner (Rajasthan).
For computation of ground water resources of Rajasthan ground water with electrical conductivity over 8 dSm-1 in the districts of western Rajasthan (3, 42,226 km2 geographical area) and over 6 dSm-1 in the districts of eastern Rajasthan has been taken by the state ground water department as unsuitable for any use and thus taken as saline ground water areas. A total of 1, 06,018 km2 area (about 31% of Rajasthan) comes under saline ground water in the state. Of this 88675 km2 area falls in western districts viz. Ganganagar, Barmer, Bikaner, Churu and Jaisalmer. District-wise saline areas are given in Table 2.34.
Table 2.34: Saline ground water areas in Rajasthan
District Geographical area
(km2) Saline area EC > 6dSm-1 (km2) Percent of district area Saline area EC > 4dSm-1 (km2) Percent of district area
Ajmer 8481 587 6.9 700 8.2
Alwar 8380 476 5.7 1200 14.3
Barmer 28367 14830 52.2 18750 66.0
Bharatpur 5100 1380 27.1 3060 60.0
Bikaner 27244 15683 57.6 19750 72.4
Churu 16830 10389 61.7 11780 69.9
Dausa 3472 101 2.9 370 10.6
Ganganagar 20634 18347 88.9 19000 92.2
Jaipur 11066 566 5.1 900 8.1
Jaiselmer 38401 29426 76.6 31426 81.8
Jalore 10640 2123 19.9 7020 65.9
Jhunjhanu 5923 119 2.0 400 6.7
Jodhpur 22850 5349 23.4 11000 43.1
Nagaur 17718 2485 14.0 6500 36.6
Pali 12307 3188 25.7 4550 36.7
Sawai Madhopur 10057 176 1.7 200 1.9
Sikar 7732 93 1.2 350 4.5
Tonk 7194 695 8.7 750 10.4
Total geographical area 342260 106018 31 141036 41
Note: EC of ground water in western Rajasthan over 8 dSm-1 and in eastern Rajasthan over 6 dSm-1
Source: Minhas and Samra(2003)
Hydro-geology:
Hydro-geogical studies indicate that state has three types of Aquifers: (a) Unconsoli -dated formations (alluvial and aeolian deposits) associated with residual hill slopes, abandoned river courses, the piedmont plains, aeolian plains of Jalore, Barmer and Jodhpur districts and catchments of river Katali in Jhunjhunu, Luni in Ajmer, Banes and Khari rivers in Udaipur, Tonk and Bhilwara districts; (b) in districts of Jaisalmer and Barmer, aquifers are in semi-consolidated sedimentary rock formations, Lathi stone formations in about 10000 km2 (2.9%) area have proved to be promising aquifers and (c) Aquifers in regions having consolidated rock formations have some water that can be used for agriculture. District wise aquifers in potential zones and area (Sq.Km.) are given in table 2.35.
Table 2.35 : District wise aquifers in potential zones and area (Sq.Km.)
S.No. District Aquifers in potential zones and area (Sq.Km.)
1 2 3
1 Ajmer Alluvium (332.5), Calc- schist ( 2002.6) , Granite-gneiss(5121.7)
2 Alwar Older Alluvium (5820.7), Quartzites (545.4), Slate (667.4)
3 Banswara Aasalt (1238.4), Lime stone (80.6), Quartzites( 78.4), Phyllite & Schist(1005.5), Granite-gneiss ( 986.5)
4 Baran Sand stone (3830.6) ,Alluvium ( 274.7),Basalt (966.8)Shale (637.1) Lime stone (1183.0)
5 Barmer Younger Alluvium ( 1540.0 ) , Older Alluvium (5614.5) Tertiary sand stone (2084.2) Lathi sand stone (1497.8) , Rhyollite
( 1306.4) Granite (303.3)
6 Bharatpur Older Alluvium(1544.5) Sand Stone (1487.5) , Quartzite ( 76.9)
7 Bhilwara Phyllite & Schist (4325.8), Granite-gneiss ( 4541.7) Sand stone (428.7) , Lime stone (60.7)
8 Bikaner Older Alluvium(1544.5) Tertiary Sand Stone (6287.0) , Nagaur sand stone (3248.4),Bilara sand stone ( 172.1)
9 Bundi Alluvium (1158.3) ,Phyllite (1667.5) , Sand stone (404.4) , Lime stone (247.8), Shale (126.7), Lime stone with Shale (635.4)
10 Chittorgarh Basalt ( 1715.3), Granite-gneiss( 1787.5), Sand stone (697.2), Lime Stone(467.1), Shale ( 1991.9), Phyllite & Schist (1551.0)
11 Churu Younger Alluvium (1920.2) , Older Alluvium (1361.2) Tertiary Alluvium (1049.8 , Nagaur lime stone (1267.3), Bilara lime stone (488.0), Jodhpur sand stone ( 353.7)
1 2 3
12 Dausa Younger Alluvium (709.2) , Older Alluvium (1902.9) , Quartzite
( 327.4), Phyllite (52.5), Granite-gneiss (73.7)
13 Dhaulpur Schist Alluvium (1430.0) , Sand stone (801.4)
14 Dungarpur Ultra base (81, Biotic Schist (282), Phyllite & Schist (1998.2), Granite-gneiss (287.6)
15 Ganganagar Alluvium (1925.4)
16 Hanumangarh Alluvium (920.7)
17 Jaipur Younger Alluvium (4383.5) , Other Alluvium (2829.0) Quartzite (540.7, Phyllite & Schist(704.6), Granite-gneiss ( 1431.9)
18 Jaisalmer Alluvium (2706.5), Tertiary sand stone (716.6),Parwar sand stone (784.1), Bhadesar sand stone (462.0) , Jaisalmer sand stone ( 568.8), Lathi sand stone ( 4502.2), Jodhpur sand stone (695.3), Granite (209.4), Rhyollite (336.3)
19 Jalore Younger Alluvium (1378.4) , Older Alluvium (6099), Granite (582.4), Phyllite (68.8)
20 Jhalawar Basalt (4732.1), Sand stone (1374.1
21 Jhunjhunu Younger Alluvium (299.2) , Older Alluvium (4220.4), Quartzite schist, Phyllite Lime stone and Granite (754.1)
22 Jodhpur Older Alluvium (826.8),Nagaur sand stone (790.4) Bilara Lime stone (2821.4), Jodhpur sand stone (10106.8), Rhyllite (383.1),Granite (1596.7)
23 Karauli Older Alluvium and Quaternary (2338.2), Sand stone (1454.9), Quartzite (108.7)
24 Kota Alluvium (1410.3), Lime stone (1180.5), Sand stone (235.9), Shale (151.5)
25 Nagaur Other Alluvium (5682.0), Palana sand stone (1005.3), Nagaur sand stone (2505.1) , Bilara lime stone (3363.6), Jodhpur sand stone (1341.3), Phyllite , Schist & Gneiss (2481.2)
26 Pali Younger Alluvium (81.2) , Older Alluvium (236.1), Erinpura Granite (3140.6) , Slate , Phyllite & Schist (1623.4), Granite-gneiss (704.2)
27 Rajsamand Mica Schist , Phyllite & Schist (251.2), ), Granite-gneiss (1735.9)
28 Swai Madhopur Alluvium (2256.3), Lime stone (583.9) , Shale (529.6), Quartzite (164.9) , Phyllite & Schist (790.9),
29 Sikar Younger Alluvium (165.2) , Older Alluvium (6010.9),Quartzite , Dolomite, Lime stone, Schist, Phyllite & Gneiss (1087.3)
30 Sirohi Alluvium (987.8), Calc. Schist & Gneiss (525.4), Phyllite & Schist (1543.4) , Granite (1550.5)
31 Tonk Alluvium (1307.8), Phyllite & Schist (4203.8), Granite & Gneiss (1014.2)
32 Udaipur Calc. Schist & Calc. Gneiss(825.8), Granite (253.1), Quartzite (151.7) Phyllite & Schist (3729.1) ), Granite & Gneiss (3300.8)

Major parts of the saline areas are restricted in the Quarternary alluvial deposits which comprises of silt, sandy clay, ‘kankar’ etc. of Eesozoic and tertiary age and form saline aquifers in the Barmer, Bikaner, Jaisalmer, Churu, Jodhpur districts. In the western districts the thickness of uncosolidated sediments is more than 300m. Semi consolidated formations occur as discontinuous aquifers with limited thickness down to100 m. The depth to water levels varies very widely in the western districts ranging from about 10m in south western parts of Jalore district to as much as about 100 m in parts of Jaisalmer and Bikaner districts. In 1999-2000, 68.9% of total irrigated area 5.61million ha. was served by ground water, 28.8% by canals and remaining 2.3% by tank etc.
Ground water potential in Rajasthan:
Due to scarcity of surface water , Rajasthan has to depend on ground water resources to a great extent .Ground water potential area in the state is 215142 sq. km.The fresh ground water resource has been made block wise in respect of Rajasthan as per guide lines given by the Ground Water Esimation Committee. Saline ground water areas with electical conductivity over 8 dSm-1 in western Rajasthan and over 6 dSm-1 in eastern Rajasthan were excluded from the usable ground water areas. On adhoc basis a very approximate estimation of dynamic recharge in the saline areas is of the order of 2790 MCM per annum (Table 2.36).

Table 2.36: Saline ground water resources in Rajasthan
District Annual recharge (MCM/yr) (for saline areas where GW salinity EC > 8dSm-1 in western Rajasthan and >6dSm-1 in eastern Rajasthan Annual recharge (MCM/yr) (for saline areas where EC of GW is over 4dSm-1
Ajmer 20.05 23.83
Alwar 52.92 130.92
Barmer 423.28 537.34
Bharatpur 138.00 305.79
Bikaner 332.17 418.09
Churu 310.35 351.49
Dausa 9.10 32.97
Ganganagar 464.07 480.51
Jaipur 26.23 44.51
Jaiselmer 372.08 397.28
Jalore 80.00 264.47
Jhunjhanu 8.31 26.71
Jodhpur 170.60 349.66
Nagaur 85.53 222.33
Pali 213.23 306.77
Sawai Madhopur 16.11 18.15
Sikar 16.61 59.92
Tonk 50.36 53.93
Total geographical area 2790.00 4024.67
Source: Minhas and Samra(2003)

The ground water resources position as on 1.1.95 & 1.4.98 is given below ( Annonymous, 2000)
1. 1.95 1.4.98
The ground water resources 13157.2 MCM 12602.1 MCM
Utilizable ground water for irrigation 11028.2 MCM 10604.4 MCM
Utilized for irrigation 6493.7 MCM 7724.5 MCM
Ground water balance 4534.5 MCM 2879.9 MCM
Stage of ground water development 58.9 % 72.8 %

In 2001 ground water development was 104% with a net negative balance of –476.0 MCM and 70% of the assessment blocks were in critical and over exploited category of water table. In major parts of the western districts average depth is between 40 to 70 m bgl. In the saline areas of eastern districts groundwater rests at depth ranging from 10m to 40m below ground level.
Present use:
About two third area of western Rajasthan and parts of eastern Rajasthan are underlain with saline ground water and potable water sources are not available as such. Ground water with EC 8 dSm-1is being used for irrigation , drinking and other domestic uses. Such water have unpalatable taste and may cause adverse effect on health. Saline water is also being used for livestock as they have higher tolerance to saline water. To provide safe drinking water, the State Govt. has commissioned a total of 91 desalination plants (50 R0 and 41 ED plants) in Barmer, Churu, Jhunjhunu, Nagaur, Bikaner, Jodhpur, Bharatpur and Jaipur districts. Due to operational and maintenance problems, difficulties are being felt to run these plants. The defence research Lab. Jodhpur has developed indigenous ED plants for their own use and commissioned in Barmer district for public. These ED plants can produce 30 cu.m/day of potable water (TDS 1500 mgl-1) from input salinity of 5000 mgl-1 TDS. Besides salinity this also removes other harmful constituents like fluoride and nitrate.
Saline ground water for irrigating salt tolerant crops is being used in Jalore, Jodhpur, Pali, Alwar and Sikar districts where the soil is coarse textured and water table is within 40 m. Farmers use saline water as life saving irrigation for kharif crops to make up moisture deficiency and also for irrigating rabi crops, namely wheat, varieties Kharchia-65, Kalyansona and Barley etc. As a management practice farmers divide their holdings in four to five plots and irrigate only one plot in one season and keep it fallow for one or more years so that salt enriched soil can be leached during rains. Brines and highly saline ground water are being used to manufacture common salt and industrial salts in part of Barmer, Jodhpur, Nagaur, Sikar, Jaipur and Bharatpur districts. With the availability of fresh canal water supplies from IGNP, the conjuctive use of saline water for irrigation is likely to increase.
In Bikaner and Churu districts the soil is coarse textured sandy and deep. The underground water has EC ranging from 2.0 to 6.0 dSm-1. In many cases the waters is alkali. This water are being used to irrigate crops like groundnut, cluster bean, pearl millet etc in kharif and mustard, wheat, cumin, fenugreek in rabi using sprinkler system of irrigation.. However due to aridity of the region the soil tend to becomes saline the use of such poor quality water for irrigation.
Periodic development of water level in state:
Water level varies with rainfall, physiology, drainage and climatic condition. The ground water condition in the state varies widely. To the East of Aravalies, depth of water is comparatively shallower than in the West. It generally varies between 10 to 25m in the eastern part ,whereas, in the western part it ranges between 20 to 140m. The water level slopes toward east and south- east on the eastern site, whereas to the west of Aravalies, it slopes towards west and north-west. Shallow water level ( 7 to 26 m) have been noted in the canal command area of Ganganagar , Banswara, Kota and Bundi districts, whereas, deeper depth of water level has been observed in the western districts of Rajasthan particularly in Jaisalmer, Bikaner, Barmer and Jodhpur.
Ground water development is significantly high in eastern part of Rajasthan as compared to the western part. The ground water recharge is relatively less in the western Rajasthan , due to low and erratic rainfall, absence of ground water resources and high evaporation . However, in some of the thick aquifers, the storage is many times the annual recharge and hence, sustained pumpage can be achieved even during dry spell.
For evaluating trend of water level and long term fluctuation, year 1984 has been considered as base year. The trend has been analysed between pre monsoon 1984 and pre monsoon ,1997 (Fig .7) on the basis of data collected from a network of 6700 Key wells in the state ground water department of Rajasthan ( Annonymous,2000)
The state has been divided into 594 ground water potential zones. Out of these 322 zones fall in “white” category, where the ground water development is < 65 %, 71 zones fall in the “Grey “ category , having 65 to 85 % stage of development. The remaining 201 zones has been categorized as “ Dark” zone, where stage of ground water development is > 85%, out of these, 173 zone are over exploited , having a stage of development > 100%.
As per studies , out of 32 districts, 26 districts showed an average depletion of water level and 6 districts showed marginal rise except certain pockets.The districts which showed water level depletion are Ajmer, Alwar, Jaipur, Jalore, Jhunjhunu, Jodhpur, Nagaur, Pali and Sirohi (Table 2.37)



Fig 7. Water Level Fluctuation in Rajasthan
Table 2.37: District critically affected by water level depletion during 1984-2000
S. No. Districts Av. drop (m) S. No. Districts Av. Drop (m)
1 Ajmer (-)5.59 6 Jodhpur (-) 6.60
2 Alwar (-)5.12 7 Nagaur (-)6.50
3 Jaipur (-)5.74 8 Pali (-)6.69
4 Jalore (-)8.00 9 Sirohi (-)6.49
5 Jhunjhunu (-)6.22 - - -

The prime reason for water level depletion is excessive withdrawl of water to meet out the ever growing demand of agriculture, domestic and industrial purposes.The sustainability of vagaries has further fallen prey to the unplanned development. Thus due to shrinking of ground water resources, wells are getting dried up and chemical quality of ground water is getting deteriorated.

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