『Abstract
The complex depositional pattern of clay and sand in most of
the areas controlled the vertical and lateral movement of nitrate
in groundwater. The variation of nitrate concentration at different
groundwater levels and the lateral distribution of nitrate in
the groundwater at two sites indicated the filtration of nitrate
by clayey formations. A rural agricultural district located in
the Vamsadhara river basin, India was selected for studying the
lateral and vertical distribution of nitrate in the groundwater
and the association of nitrate with other chemical constituents.
The nitrate concentrations in the groundwater are observed to
vary between below detectable limit and 450 mg NO3/L.
The sources for nitrate are mainly point sources (poultry farms,
cattleshed and leakages from septic tanks) and non-point sources
(nitrogenous fertilisers). The nitrate concentrations are increased
after fertiliser applications. However, very high concentrations
of nitrate are derived from animal wastes. Relatively better correlations
between nitrate and potassium are observed (R = 0.74 to 0.82).
The better relationship between these two chemical constituents
in the groundwater may be due to the release of potassium and
nitrate from both point and non-point sources. The nitrate and
potassium concentrations are high in the groundwater from clayey
formations.
Keywords: Nitrate; Potassium; Groundwater; Clay membrane; Point
source; India』
Introduction
Study area
Materials and methods
Results
Discussion
Conclusion
Acknowledgements
References