INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 3, No 6, Copyright by the authors - Licensee IPA- Under Creative Commons license 3.

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1 INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 3, No 6, 2013 Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0 Research article ISSN Synthesis of parameters used to check the suitability of water for irrigation purposes Taqveem Ali Khan 1, Adil Abbasi. M 2 1- Department of Geology, A.M.U. Aligarh A.K.Khan Inter College, Amroha, Jyotiba Phoole Nagar taqveemk@yahoo.co.in doi: /ijes ABSTRACT The present study is carried out - in the area near river Ganga where water table is lying with in the vicinity of 0.76 to meter below ground level (m.b.g.l). The study is carried out to ascertain the suitability of groundwater for irrigation purposes. The parameters used to ascertain the suitability of water for irrigation purposes are synthesized. The parameters used for the purpose are; electrical conductivity, sodium adsorption ratio, sodium percent, residual sodium carbonate, magnesium ratio, permeability ratio and Kelly s ratio. U.S. salinity laboratory diagram and Wilcox diagrams were also prepared. 16% of the samples show high electrical conductivity. Rest of the parameter show groundwater is suitable for irrigation purposes save magnesium ratio which shows groundwater may be toxic to plants- so crop susceptible to high magnesium content can be avoided in the area and crops requiring high Mg contentment can be grown in the area. The ionic contribution to the groundwater is not from the atmospheric precipitation but from rock water interaction as shown by high Na/Cl and K/Cl ratios. Keywords: Sodium adsorption ratio, residual sodium carbonate, Kelly s ratio, magnesium ratio. 1. Introduction Any form of life cannot survive without water. Older civilizations flourished on the banks of rivers. Major towns of the world are on the banks of rivers. Group of peoples will move in search of water and will settle when adequate amount of water is found. They would migrate when this water will about to finish and would search another source of water. Modern knowledge has led the mankind to understand that the quality of water is as important as its quantity. Agencies world over have worked out methods to check the suitability of water for its different uses namely, domestic, irrigation and industrial (WHO 1989; USEPA 1992 ICMR 1975, BIS 1986). Groundwater is not static. It is dynamic in nature and keeps on moving. The motion of groundwater along its flow path increases the concentration of the chemical species. The presence of these chemical special species could reveal important information on the geologic history of the aquifers and the suitability of groundwater for domestic, agricultural and industrial purposes (Aghazadeh 2010). India is an agrarian economy. The survival of its people particularly of those living in rural areas lie on the resources it generates from the agricultural practices. Groundwater is the main source of irrigation in these activities. The purpose of the present case study is to synthesize all the parameters used in assessing the suitability of water for irrigation. The result of the study will help the people of the study area to know the quality of water with regard to agriculture and can plan crop cultivation accordingly. Further, the planners will get Received on May 2013 Published on July

2 the guidance to make pragmatic planning. The syntheses of parameters can help workers of the same field to use them in their respective areas. 2. Material and method Analytical results of the 18 Groundwater samples collected from open wells were used to carry out the study. For data collection and analytical work the norms laid down by American Public Health Association (APHA 1989; 1995) were used. The samples were collected so as to cover the entire area (Figure 1). 3. Study area Figure 1: Map showing sample locations in the study area River Ganga has a significant economic and environmental value in India. It start from the Himalayas and ends in the bay of Bengal traversing a course of more than 2,500 km passing through the plains of north and eastern India. The vast Ganga basin accounts for 26% of India s landmass, 30% of its water resources and more than 40% of its population. The aquifer of this large basin is one of the world s largest aquifer repositories. The study area Ganga Nim sub basin is the part of the central Ganga plain. The area forms the south eastern part of the Bulandshaher district and bounded in the east by the Ganga River and in the west by the Nim River (Figure 1). It is spread over an area of sq. kms. It lies between 28 o 5 and 28 o 22 N latitudes and between 78 o 15 to 78 o E longitudes. The Ganga - Nim sub - basin falls under the subtropical climatic zones of India. During summer temperature rises to 45 o C and falls to 4 o C during winters. The average rainfall in the area is mm. Three types of soils have been found in the area: sandy loam, sandy to loam, and loam to clay loam. Near the track of river Ganga the soil type is sandy loam. It is saline in nature, consequent to shallow groundwater table. The salt efflorescence appears to be a common feature of the entire tract which is locally called usar. Sandy loam to loam type of the soil covers the major portion of the upland tract. The soil varies in color from light brown to deep brown and the texture of the soil is sandy to good quality loam. These soils are well drained. Clay to clay loam type of soil is only in a small of the portion on left side of the lower Ganga canal. 2032

3 4. Result and discussion 4.1 Hydrochemistry The groundwater of the study area is alkaline in nature where ph ranges between The electrical conductivity of the water sample ranges between micromhos/cm at 25 o C. Chloride concentration in the groundwater samples of the area varies from mg/l. Save at two location water is suitable for drinking purposes. Sulphate concentration varies from mg/l. Except at one location the water is within the permissible limit of 250 mg/l (ICMR.1975, W.H.O., 1984) Sodium is found to range between 4.98 to 216 mg/l. Save the location number 17 water samples were found within the limit. Potassium varies between 2mg/l to 172mg/l. The calcium ranges between 39 to 151 mg/l. Magnesium was found to vary from 28 to 207mg/l. Total hardness varies from 104 to 760mg/l. Total dissolve solids range between 233 to 281mg/l. In all the groundwater of shallow aquifer of the area that is used for drinking and other household purposes is potable, hard, and alkaline in reaction and slightly -mineralized (Khan and Abbasi 2003). 4.2 Irrigation water quality Following parameters are considered important to determine the suitability of water for irrigation purposes. 1. Electrical conductivity 2. Sodium adsorption ratio. 3. Sodium percentage. 4. Residual sodium carbonate. 5. Magnesium ratio 6. Permeability index. 7. Kelly s ratio Electrical conductivity Electrical conductivity is a potent tool to measure the salinity hazards to crops. EC reflects the TDS in groundwater. The EC of the area is compared with the table of EC classification (Table 1) (Raghunath 1987) and it was found that only three samples fall in doubtful class i.e. 16% and 14 samples fall in good category i.e., 77.78% and only one sample in excellent class ie. 5.56% Table 1: Quality of irrigation water based on electrical conductivity Quality of Water Electrical conductivity Percentage (micromhos/cm) Samples (%) Excellent < Good Doubtful Unsuitable > of 2033

4 Sodium adsorption ratio (SAR) SAR is defined by U.S. Salinity Laboratory (1954) where the ion concentrations are expressed in milliequivalents per liter. Experiments conducted at the U.S. Salinity laboratory show that the SAR reasonably predicts the degree to which irrigation water tends to enter into cation exchange reaction in soil. High values of SAR imply a hazard of sodium replacing adsorbed calcium and magnesium, a situation ultimately damaging to soil structure. The values are empirical and of otherwise limited geochemical significance (Hem 1991). SAR is expressed as SAR = Na + / [(Ca 2+ Mg 2+ )/2)] 1/2. All the concentrations are in meq/l. As per the classification given in table 2 the water is classified as excellent for irrigation purposes. For more detailed analysis the US salinity diagram is prepared (Figure 2). The US salinity lab s diagram (US Salinity Lab Staff, 1954) is widely used for rating irrigation waters, where SAR is plotted against EC. The analytical data plot is shown in Figure 2. The USSL diagram depicts that the groundwater of the area fall in C2SI class. This suggests: groundwater of the area has medium EC hazard and low SAR hazard. Table 2: Alkalinity hazard of water Sodium adsorption ratio Alkalinity Hazard Quality of Water (SAR) 2- <10 S1 Excellent S2 Good S3 Doubtful >26 S4 Unsuitable Figure 2: Classification of groundwater quality in the study area 2034

5 Percent. Sodium The tendency for a water to enter into cation exchange reactions was commonly evaluated in terms of the sodium percentage. It is the percentage of total cations made up by sodium. Because divalent cations usually are preferentially held in exchange position on clay minerals, the extensive displacement of Ca and Mg by Na is unlikely unless the sodium percentage is considerably higher than 50 or the total concentration of solutes is large(hem 1989). Sodium percent is an important criterion in classifying irrigation water. A set proportion of air and water in the pore spaces is required for the proper growth of plants. The Sodium content of water reacts with the soil and accumulates in the pore spaces thus reducing its permeability. Sodium contents is expressed in terms of percent sodium or soluble sodium percentage. The Indian standards suggest maximum of 60% sodium is permissible for irrigation water. The range of sodium percent in the samples of the area is That is all the samples are below the threshold of 50 percent. This suggests the water has no sodium hazard and fit for irrigation as far as the sodium percent is concerned. Wilcox (1955) suggested a graphical method for knowing the suitability of water for irrigation purposes. The proposed method is widely used and is based on percent sodium and electrical conductivity plot. The diagram consists of five distinct areas i.e., excellent to good, good to permissible, permissible to doubtful, doubtful to unsuitable and unsuitable. The data was calculated and subsequently plotted on the Wilcox diagram (Figure 3). Figure 3: Wilocox diagram for classification of groundwater quality in the study area The plot on the diagram shows that maximum number of samples are in category of very good to good category and few samples are in good to permissible category. This arrangement directs the groundwater of area is suitable for irrigation purposes Residual sodium carbonate Residual sodium carbonate (RSC) has been calculated to determine the hazardous effect of carbonate and bicarbonate on the quality of water for agricultural purpose and is expressed by the equation RSC = (CO3 +HCO3) - (Ca+ Mg) 2035

6 where all ionic concentrations are expressed in meq/l (Eaton 1950). The classification of irrigation water according to the RSC values (Table 3) is waters containing more than 2.5 meq/l of RSC are not suitable for irrigation, while those having 2.93 to 2.3meq/l are doubtful and those with less than 1.25 meq/l are good for irrigation(aghazadeh 2010). Based on this classification, all of groundwater samples belong to the safe category. Table 3: Gives the results and rating of waters based on residual sodium carbonate (WHO 1989) RSC meq/l Irrigation Class Number of samples < 1.25 Safe All Marginal - > 2.50 Unsuitable Magnesium ratio Calcium and magnesium in water are, generally, in the state of equilibrium. The large amount presence of magnesium in water adversely affects soil-quality. It converts the soil into alkaline in nature thus reducing its crop yield. It is expressed as Mg ratio = [Mg / (Ca + Mg)] x 100, where all values are in epm. Magnesium ratio of more than 50% in a water body will make the water poisonous to plants. The magnesium ratio in the groundwater samples of the area ranges from 56 to 99 percent. So all the samples fall in the dangerous category. The high magnesium in water also causes heart diseases Permeability index The soil permeability is affected by consistent use of irrigation water which increases the presence of sodium, calcium, magnesium and bicarbonate in the soil (Chandu et al 1995). The permeability index (PI) is used to measure the suitability of water for irrigation purpose when compared with the total ions in meq/l. The PI is expressed as follows Na+ + (HCO- 3)0.5 P I = x 100 Ca++ + Mg++ + Na+ where, all values are expressed in meq/l. Doneen (1964) has developed a graph based on the permeability index (PI) and total salt concentration for classification of irrigation water. On the bases of this the water can be of three types; class I, class II, class III. The average of PI in the area comes out to be 31.3, so it falls in the class I type Kelly s ratio Suitability of water for irrigation purposes is also assessed on the bases of Kelly s ratio (Kelly 1951). Ratio of sodium verses calcium and of sodium verses magnesium is used as Kelly s ratios. Groundwater having Kelly s ration more than one is considered not-suitable for irrigation purposes. Kelly s ratio of the groundwater samples of the area ranges between 0.56 and with mean of As per this criteria the groundwater is suitable for irrigation purposes. 2036

7 4.3 Source of ions in the groundwater The dissolve ionic species in the groundwater are the resultant product of weathering of rock forming minerals with minor contribution from atmospheric precipitation and anthropogenic activities (Berner and Berner 1987). The contribution of atmospheric sources to the dissolved salts in the aquatic water can be assessed by considering the rain water chemistry or by taking the ratios of elements to Cl (Stellard et al 1983, Sarin et al 1989). The average Na/Cl and K/Cl ratios of the groundwater in the area comes out to be and respectively. These ratios are higher than the marine aerosols (Na/Cl = 0.85 and K/Cl = ) (Zhang et al 1995). This suggests that the contribution in from the atmospheric precipitation is limited in the area. The contribution in the area is from rock water interaction. 5. Conclusion The electrical conductivity of 16% of the samples is high so as to put the water of these samples in doubtful class. Rest of the sample have EC good to excellent class for irrigation purposes. SAR values are <10 classifying groundwater of the area as excellent for irrigation. The groundwater of the area has sodium percent less than 50- the India s threshold value- and suitable for irrigation purposes. In the Wilcox diagram plot the groundwater samples fall in good to permissible category. RSC values are less than 1.25 suggesting the suitability of water for irrigation. Magnesium ratio in the groundwater samples ranges between 56 to 99 percent making it not suitable for irrigation. Both permeability index and Kelly s ratio permit groundwater ratio to be used for irrigation purposes. The ionic species present in the groundwater are due to the rock water interacting as suggested by high Na/Cl and K/Cl ratios. The water table in the area is shallow and ranges between 0.76 to m.b.g.l. The area is sub tropical climatic zone where the evaporation rate is high. Owing to these conditions the mineral contents in the water should have been high. But as the area is near the river Ganga, which is flowing in low lying tract following the topography, the horizontal flow of groundwater towards the Ganges reduces the staying time of water in the vadose zone. This act as washing of the salts to the river Ganga. So, the salts content near the rivers are less and make water suitable for irrigation. 6. References 1. Aghazadeh Nosrat., Asghar Asghari Mogaddm, (2010), Assessment of groundwater quality and its suitability for drinking and agricultural uses in the Oshnavieh area, Northwest of Iran, Journal of environmental protection, 1, pp APHA, (1989), Standard methods for examination of water and wastewater, 17th edn. American Public Health Association, Washington, DC. 3. APHA, (1986), Standard methods for the examination of water and wastewater, 19th edn. American public Health Association, Washington, DC. (1995) BIS: Guidelines for quality of irrigation water, Bureau of Indian Standards, New Delhi,. 4. Berner, E.K. and Berner, R.A., (1987), The global water cycle: geochemistry and environment. Prentic Hall, Englewood cliff. 5. Chandu, S.N., N.V.Subbarao and S.R.Prakash., (1995), Suitability of groundwater for domestic and irrigational purposes in some parts of Jhansi District, U.P.Bhujal Newa, 10(1), pp

8 6. Doneen, L.D., (1964), Notes on water quality in agriculture, published as water science and engineering, Paper 4001, Deptt of water, Science and engineering, University of California, Davis.. 7. Eaton, F. M., (1950), Significance of carbonate in irrigation water, Soil science, 69(2), pp Hem J D., (1991), Study and interpretation of the chemical characteristics of natural water, 3rd edn. Book 2254, Scientific Publ. Jodhpur, India. 9. I.C.M.R., (1975), Manual of standards of quality for drinking water supplies. I.C.M.R., New Delhi, 2nd edition. 10. Kelly WP., (1951), Alkali soils-their formation properties and reclamation. 3rd edition. Reinhold Publication, New York, USA, p Khan, T. A. and M. A. Abbasi., (2003), Hydrochemical studies of shallow groundwater in the Dibai Block of Bulandshahar Distt, U.P., Pollution Research, 22(4), pp Ragunath, H. M., (1987), Groundwater, Wiley Eastern Ltd., New Delhi, p Stellard, R.F. and Edmond, J.M., (1983), Geochemistry of the Amazon 2: The influence of geology and weathering environment on dissolve load. Jour. Geophys. Res., 88 pp , 14. Sarin, M.M., Krishnawamy, S., Dilli, K., Somayajulu, B.L.K, and Moore, W.S., (1989), Major in chemistry of Ganga Brahmaputra river system: weathering processes and fluxes to the bay of Bengal, Geochim Cosmochim Acta, 53, pp USEPA, (1992), Guidelines for water use. USEPA, Washington, Tech. Report, 81, p US Salinity Lab Staff (1954), Diagnosis and improvement of saline and alkali soils. USDA, USA. 17. W.H.O., (1984), Guidelines for drinking water quality, W.H.O, Geneva. 18. WHO (1989), Health guidelines for the use of waste water in agriculture and aquaculture. Report of a WHO Scientific Group Technical report series, 778, WHO Geneva, p Wilcox L V., (1955), Classification and use of irrigation waters. USDA Circular No.969, p Zhang, J., Huang, W.W., Letolle, R, and Jusserand, C., (1995), Major element chemistry of Husanghe (Yellow river), Chine weathering processes and chemical fluxes, Journal hydrology, 168, pp