Characteristics of Groundwater and Soil Chemical Variation of Polpithigama Area, Sri Lanka

Young, Sansfica M.; Ishiga, H.

Characteristics of Groundwater and Soil Chemical Variation of Polpithigama Area, Sri Lanka

2021

Young, Sansfica M. | Ishiga, H.

Elemental compositions of water, and surface and subsurface soils indicate characterization and mobilization of elements within soil profiles. The chemical variations of groundwater (n = 21) and surface and subsurface soils (n = 18 each) of the Polpithigama area were examined to determine elemental spatial variation in the area. Physico-chemical parameters (pH, electrical conductivity (EC), dissolved oxygen (DO), oxygen reduction potential (ORP)) and NO₃⁻, PO₄²⁻, Mn, Fe, and F were analyzed for the water samples in the field using field test kits. Soil samples were analyzed using X-ray fluorescence for 22 major and trace elements. Iron, Mn, NO₃⁻, and PO₄²⁻ concentrations in water are lower than the threshold values of WHO. The fluoride content was increased with high elevation even within a short distance. The fluoride and phosphate are highly variable between the soil layers and are preferably retained in the surface soil. The vertical variation is resulted by intensive weathering under tropical conditions, mobility of ions, variation of elements, and variation of soil constituents such as different contents of organic matter and clay content consisting of high total sulfur (TS) contents. Migration of some ions to the groundwaters of the area is possible due to high mobility of elements and thus the compositions of some elements show variations in the surface and subsurface soils.

Показать больше [+]