Primary salinity is caused by natural processes such the accumulation of salt from rainfall over many thousands of years or from the weathering of rocks.

1. Inland Salinity Development in
Anuradhapura
AG 4015
 2017T00094
 2017T00097
 2017T00111
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2. Introduction
 Salinization is an increase in the total dissolved solids (TDS) of the aquifer
caused by natural or anthropogenic factors.
 Salinity is the accumulation of salt in land water to a level that damage the
natural and built environment,
 The processes and sources of salinization vary for inland and coastal aquifers.
 Anuradhapura district is dry zone agricultural area. annual rain fall below the
1500mm.
 This area has more possibility to develop salinity.
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3. • Soil pH drastically change due to salinity,
• pH usually increases with an increase in salinity due to the presence of
sodium ions.
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Fig. Sources of inland salinization of groundwater

4. Factors affect for the salinity
 Major anthropogenic sources of inland salinization include,
• Irrigation of dry areas that lack proper drainage.
• Increased evaporation and decreased precipitation facilitated by climate
change.
• Excessive groundwater pumping.
• wastewater with a high salt content being disposed of carelessly by industries
onto the surface.
• The distribution and rates of precipitation.
• Evapotranspiration and recharge rates.
• Type of aquifer material and its characteristics, residence time.
• Nature of the discharge areas
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5. Effect of inland salinity
 Salinization, which is the biggest troublemaker in Anuradhapura district.
 It will result in the deterioration of the physical, chemical, fertility, and
biological properties of soil
 And loss of organic matter in soil due to excess salt and sodium
accumulation in fertile agricultural areas.
 plant functions such as taking plant nutrients from soil including nitrogen
will decline and stop completely and production will be adversely affected.
.
How to avoid
 Maintain the adequate vegetation cover
 Adding gypsum or fertilizer to plant growth
 Planting salt tolerant grass
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6. Summary
 Anuradhapura district is dry zone agricultural area annual rain fall below
the 1500mm.
 Salinity is the saltiness or amount of salt dissolved in a body of water.
• There are some factors affect for the salinity like Excessive groundwater
pumping. ,Irrigation of dry areas that lack proper drainage, The distribution
and rates of precipitation, Evapotranspiration and recharge rates
 Salinity will result in the deterioration of the physical, chemical, fertility,
and biological properties of soil
 It has been revealed that soil salinity has increased with the increase of
cropping duration of Agro-wells. After the next 25 years E/C values can be
increased up to “medium salinity “ level (up to 0.4 ds/m) and after the next
40 years E/C values can be increased up to “high salinity “ level (more than
0.8 ds/m) under the current condition.
References
 R.S. Dharmakeerthi, et al, “Manual of Soil Sampling and Analysis”, Soil
Science Society of Sri Lanka, Peradeniya, 2007.
 International Research Centre (InRC), University of Peradeniya, Sri Lanka,
Grants Reference Number: InRC/RG/13/06 P.B.
 Dharmasena, “Guidelines for Use of Ground Water in the Dry Zone:
Project Terminal Report”, FCRDI, MahaIluppallama, 2000.
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