Surface and subsurface water quality appraisal for irrigation
R K Isaac1, T K Khura, J R Wurmbrand
1Department of Soil water Land Engineering and Management, Allahabad Agricultural Institute-Deemed University, Allahabad, U.P., 211007, India, isaac_rk@hotmail.com
Environmental Monitoring and Assessment
|December 23, 2008
Summary
Irrigation water from various sources in Allahabad was chemically analyzed. Most water samples are suitable for agricultural use, with only minor concerns regarding specific ion concentrations.
Area of Science:
- Agricultural Science
- Environmental Science
- Water Quality Assessment
Background:
- Irrigation water use is vital for agriculture but poses environmental and health risks.
- Assessing water suitability for irrigation is crucial for sustainable farming practices.
Purpose of the Study:
- To chemically analyze water samples from diverse sources in Allahabad's Chaka block.
- To determine the suitability of these water sources for irrigation based on salt content and chemical parameters.
Main Methods:
- Collection of 44 water samples from canal, sewage, confined and unconfined tube wells, and traditional wells.
- Chemical analysis of water samples for parameters including pH, electrical conductivity, and ion concentrations.
- Classification of water based on salt content and calculation of indices like Sodium Adsorption Ratio (SAR) and Residual Sodium Carbonate (RSC).
Main Results:
- Water samples generally exhibited suitable pH (7.17-8.42), with sewage water being an exception (7.34-9.04).
- Electrical conductivity ranged from 0.26 to 1.37 millimhos/cm, indicating low to moderate salinity.
- Key parameters like SAR (1.17-2.74), RSC (-4.46 to -1.07), and SSP (63.97-28.15) were within permissible limits for most samples.
Conclusions:
- The majority of analyzed irrigation water sources in the Chaka block are suitable for agricultural applications.
- Careful monitoring is advised, particularly for sewage water and specific ion concentrations in certain locations, to mitigate potential risks.
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