Light scattering and consequent color change in Lukha River due to suspended aluminosilicate particles during winter months

• Published in: International Journal of Energy and Water Resources Vol. 6; no. 1; pp. 121 - 132
• Main Author: Kumar, V.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.03.2022; Springer Nature B.V
• Subjects: Aluminosilicates; Aluminum; Aluminum silicates; Analytical chemistry; Aquatic life; Aquatic Pollution; Cement; Coal mining; Color; Coloration; Creeks & streams; Earth and Environmental Science; Energy; Environment; Lakes; Light scattering; Morphology; Original Article; Photon correlation spectroscopy; Physicochemical properties; River beds; River flow; Rivers; Scanning electron microscopy; Scattering; Sea level; Sediments; Silicon; Waste Water Technology; Water analysis; Water Management; Water Pollution Control; Water Quality/Water Pollution; Water sampling; Winter; X-ray spectroscopy; Bangladesh; India; Blue River; Meghalaya; Glassy fish; Acid mine drainage; Mining pollution; Turquoise River
• ISSN: 2538-3604; 2522-0101
• DOI: 10.1007/s42108-021-00126-4

Lukha River flows in the Jaintia Hills region of Meghalaya (India). Since 2007, every year during winter months, the river turns turquoise to sky-blue in color with white-powdery sediment at river-bed throughout the coloration period, and presence of dead fishes floating on water surface during the early days of coloration. An inspection of the water sample revealed that the color of river water is actually not ‘turquoise to sky-blue’, but appears so in the river environment, is indicative of a physical phenomenon of scattering of light by suspended particles and the white-powdery precipitate on river-bed making the water appear blue/turquoise. The result of physicochemical properties (17 parameters) of river water gave no clue to the coloration phenomena. The dynamic light scattering analysis revealed the mean particle size of suspended particles in the colored portion of river water ranging between 341.07 and 446.33 d.nm. Scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis of extracted particles indicated amorphous morphology and demonstrated the content of Si, Al, S, and O as main elemental components, and the white sediment at river-bed demonstrated the content of Si, Al, and O as main elemental components. A glassy fish ( Parambassis ranga ) was found surviving in a remote pocket of colored length of river. The study concluded that the coloration of river during winter months is due to scattering of light by suspended aluminosilicate particles, precipitation of these particles as white-powdery sediment on river-bed makes the scattering visible.