ASSESSMENT AND CHARACTERIZATION OF WATER QUALITY AND POLLUTION IN THE COASTAL ENVIRONMENT OF PEKALONGAN, CENTRAL JAVA, INDONESIA

Coastal waters are complex ecosystems essential to environmental, economic, and social sustainability.The dynamic characteristics of the Pekalongan coast are shaped by both natural processes and human activities.This study analyzes pollution characteristics at the Loji and Sengkarang estuaries.In-situ sampling was conducted to measure pH, temperature, salinity, and dissolved oxygen (DO), while exsitu laboratory analysis was used to examine BOD, COD, TSS, nitrate, phosphate, and total coliform levels.The overall water quality was assessed using the Pollution Index and visualized through a geospatial approach.Results show that pollution indices in Pekalongan's coastal waters fall into the "slightly polluted" to "heavily polluted" category, with varying scores at different stations.The Loji Estuary exhibited higher pollution levels than the Sengkarang Estuary.Coastal areas were generally more polluted than open sea areas.The primary sources of pollution are human activities, including industry, fishing, port operations, agriculture, and residential settlements.A multidisciplinary approach is recommended to foster effective dialogue among researchers, environmental advocates, and stakeholders for the sustainable management of coastal ecosystems.