Analysis of Detergent Content and Diatom Abundance in the Waters of Pakning Village, Bukit Batu Subdistrict, Bengkalis Regency, Riau

Abstract

Water pollution from domestic waste, particularly detergents, is a serious problem that can disrupt aquatic ecosystems and the lives of phytoplankton, such as diatoms. Diatoms are biological bioindicators sensitive to changes in water quality. This study was conducted in April 2025 in the waters of Pakning Asal Village, Bukit Batu Subdistrict, Bengkalis Regency, Riau Province. The objectives of this study were to analyse detergent content, assess diatom abundance, and determine the relationship between the two. Samples were collected at three stations representing residential, mangrove, and industrial areas. Detergent content was analysed using the MBAS method with a UV-Vis spectrophotometer, while diatom identification and abundance analysis were conducted microscopically in the laboratory. The results showed that the highest detergent content was found at Station I (2.8676 mg/L) and the lowest at Station III (0.5152 mg/L). The highest diatom abundance was found at Station III (390.625 ind/L) and the lowest at Station I (248.2 ind/L). Rhizosolenia sp. was the dominant species found at all stations. Regression analysis showed a weak negative relationship between detergent content and diatom abundance (r = 0.342; R² = 0.117), indicating that detergent is not the main factor influencing diatom abundance. In conclusion, although detergents contribute to diatom community variation, other environmental factors such as nutrients, salinity, and light intensity also play significant roles.