The Use of Landsat TM Data in the Study of Total Suspended Solids in Merbok Estuary, Kedah

Estuary is an area where the interaction occurs between fresh water and salt water as the semi-closed sea-side communicates directly with the open sea where the salt water of dilution by freshwater flows from land drainage. The characteristics of estuaries are difficult to determine accurately because they are different in terms of their biological, chemical and physical. Because of their natural characteristics such as sheltered, shallow and calm, humans have benefited the estuaries as their source of food, transportation and development sites especially to the inland areas located far from the coast. However, the industrial activities have affected the areas by changing on the natural balance in the estuarine and pollution due to industrialization. In order to observe any changes in the area and to detect the pollution, remote sensing technology has been proven to be effective for observation of water bodies especially for total suspended solids (TSS). In this study, Landsat TM satellite image on 14 December 2009 was used to demonstrate the feasibility of TSS distribution mapping map in the lower Merbok estuary. In order to map the TSS distribution, a multiple regression algorithm was built using multi-band data for retrieval of the water constituent and the data were combined for multi-date regression analysis. In this study, the best R and RMS values were 0.96 and 18.68 mg/l. The coefficients obtained from the regression analysis were then used to map the suspended sediments. From the map analysis, assisted with the river discharge and tidal data, it was observed that the primary controlling factor to the TSS distributions in the area is the river discharge. The second predominant factor is tidal cycles. The presence of tidal cycles tends to increase or decrease the advections of the plume water.