Assessing river ecosystem health using remote sensing and geographic information system (gis) techniques: a case study in Jeli, Kelantan

This study assesses the health of the river ecosystem in Jeli, Kelantan, which has been increasingly affected by land use change and anthropogenic pressures. The objectives are to evaluate the river ecosystem health and to produce a thematic map of water quality indicating ecosystem health using remote sensing and Geographic Information System (GIS) techniques. Landsat 8 imagery was processed to generate the Normalized Difference Water Index (NDWI), Normalized Difference Turbidity Index (NDTI) and Normalized Difference Chlorophyll Index (NDCI), which were then analyzed and stacked to classify river health. Ground truth data for turbidity and dissolved oxygen (DO) were collected and used for accuracy assessment through confusion matrices and able to get overall accuracy over 70%. The findings indicate that most river sections exhibit good ecosystem health, particularly in upstream areas, while moderate degradation was detected in zones near recreational or agricultural activity. The study recommends the integration of high-resolution data, seasonal monitoring and additional water quality parameters in future research to support more comprehensive and precise river management strategies.