Status of Pond Waters for Irrigation in Kanyakumari District, Tamilnadu, India

 

Dr. N.K. Amaliya¹* and Dr. Sugirtha P. Kumar²

¹Assistant Professor, Department of Chemistry, Women’s Christian College, Nagercoil -629001

²Associate Professor, Department of Chemistry, Women’s Christian College, Nagercoil -629001

*Corresponding Author E-mail: amaliya87@gmail.com

Ponds are considered to be the traditional water resource for irrigational purpose in India. Kanyakumari district is blessed with many perennial ponds. But many of these are being polluted drastically due to the increased human population and rapid industrialization. So in this study, the pond water samples one each from four taluks of Kanyakumari district were chosen and analyzed on their suitability for irrigation purpose based on the values of Sodium Hazard(EC), Sodium Adsorption Ratio(SAR), Residual Sodium Carbonate(RSC), Magnesium Hazard(MH), Sodium Percent(%Na), Total Hardness(TH) and Total Dissolved Solids(TDS). Finally the results predicted their suitability for irrigation purpose.

 

 

 

INTRODUCTION  

Earth is a unique planet in the solar system and in the universe to originate and flourish living creatures, only because of its important factor (i.e. Water). Various water sources used for industrialization and agricultural purposes includes: ponds, lakes, rivers and dams. But these water bodies are drastically polluted because of discharge of effluents from industries, agricultural runoff and due to domestic activities like washing of clothes, cleaning of animals etc. so water quality evaluation prior to its use in irrigation will help in arresting any harmful effect on plant productivity and ground water recharge. Irrigational water quality depends upon the kind and amount of salts presence in water which in turn will affect the crop growth and its development. Waters with high salt concentration influences osmotic pressure on soil solution and it will affect the ability of plants to absorb water through their roots¹.

 

Study area

In India, Kanyakumari district lies at its southernmost tip with seas bounded on its three sides and by Western Ghats bordering on the northern side. It comprises of four taluks namely: Agastheeswaram, Vilavancode, Kalkulam and Thovalai.  In the present study, different ponds from four taluks of Kanyakumari district were selected and were analyzed on their suitability for irrigation purpose.

 

MATERIALS AND METHODS:

The pond water samples, one from each taluk were collected for a period of one year from Aug 2011 to Aug 2012. The chemical characteristics of water were analyzed as per the standard procedure of APHA² and their irrigational water suitability were found out using the factors such as salinity hazard (EC), residual sodium carbonate (RSC), sodium adsorption ratio (SAR), total hardness (TH), total dissolved solids (TDS), sodium percent (%Na) and magnesium hazard (MH)³.

 

Salinity Hazard (EC)

It is based on the electrical conductivity value of the water sample. It means that excess salt concentration increases the osmotic pressure of the soil, which will enable the plants to absorb water from soil through their roots leading to physiologically drought condition to the plants. EC < 700 µmhoscm^-1 - little / no threat to most crops; EC > 3000 µmhoscm^-1 -limit the plant growth⁴.

 

Fig 1: Pictorial representation of the study area

 

Sodium Adsorption Ratio (SAR)

It is determined by the absolute and relative concentrations of cations⁵.

Sodium adsorption ratio (SAR) =

 

If the irrigational water is enriched with Na⁺ ions, then uptake of Na⁺ takes place with the release of Ca²⁺ and Mg²⁺ into the soil leading to soil aggregation which in turn will also reduce the soil permeability due to this ion exchange reaction.

 

Sodium Percent (%Na)

In irrigational water it is expressed in terms of percent sodium or soluble sodium percentage.

 

% Na =   × 100

 

High percentage of Na⁺ with respect to (Ca⁺, Mg²⁺, Na⁺) in irrigation water causes deflocculation and impairing of soil permeability⁶.

 

Magnesium Hazard (MH)

It is calculated using the formula given below:

 

Magnesium hazard (MH) =   × 100

 

If its value is greater than 50, it will adversely affect the soil quality and rendering the soil unfit for cultivation.

 

Residual sodium carbonate (RSC)

It is used to find the suitability of water for irrigation in clay type soils where it will have high cation exchange capacity⁷.

 

Residual sodium carbonate (RSC) = (CO₃^2- + HCO₃^-) – (Ca²⁺ + Mg²⁺)

 

RESULTS AND DISCUSSION:

The results for different pond water samples from four taluks of Kanyakumari district with regard to irrigational quality parameters are tabulated below:

 

 

Table 1: salinity hazard status of four different pond water samples

 

 

Table 2: SAR status of four different pond water samples

 

Table 3: sodium percent status of four different pond water samples

 

Table 4: RSC status of four different pond water samples

 

Table 5: MH status of four different pond water samples

 

Table 6: TH status of four different pond water samples

 

Table7: TDS status of four different pond water samples

 

So from the above results, it is clearly understood that the samples chosen for the present study are best suiting for irrigation purpose.

 

CONCLUSION:

Thus from the present study the status of the pond waters from four taluks of Kanyakumari district on their suitability for irrigation based on EC, SAR, RSC, %Na, MH, TH and TDS were found and was concluded as best suitable for irrigation. But it’s our prime duty to preserve the pond waters, which are considered to be the wealth of our country from being polluted by careful periodic monitoring.

 

REFERENCES:

1.        Glover, C.R. Irrigation water classification systems. Guide A-116. Cooperative extension service, college of agriculture and home economics, New Mexico State University. 1996.

2.        APHA. “Standard method for examination of water and waste water”, American Public Health Association, Washington, D.C. 1989.

3.        Yidana, S.M, Ophori, D and Banoeng-Yakubo, B. Hydro geological and hydrochemical characterization of the Voltaian Basin: The Afram Plains Area. Environmental Geology. 53: 2008; pp: 1213-1223.

4.        Tijani, M.N. Hydrochemical assessment of ground water in Moro area, Kwara State, Nigeria. Environmental Geology. 24: 1994; pp: 194–202.

5.        Karanth, K.R. Ground water assessment, development and management, Tata McGraw Hill, New Delhi. 1987; pp: 720.

6.        Singh, A.K, Mondal, G.C, Suresh Kumar, T.B, Singh, B.K, Tewary, A, and Sinha. Major ion chemistry, weathering processes and water quality assessment in upper catchment of Damodar river basin, India. Environmental Geology.54: 2008; pp: 745–758.

7.        Ragunath, H.M. Groundwater: Wiley Eastern Ltd, New Delhi, India.1987; pp: 563.

 

 

Received on 27.01.2015         Modified on 20.02.2015

Accepted on 25.02.2015         © AJRC All right reserved