Water quality of Batang Ai Reservoir at Different depths and distances from cage culture site and abandoned cage culture

• Main Author: Elaine, Tai Szewei
• Format: Final Year Project Report
• Language: English
• Published: Universiti Malaysia Sarawak, (UNIMAS) 2014
• Subjects: GE Environmental Sciences
• Online Access: http://ir.unimas.my/id/eprint/26751/1/Elaine%20Tai%20Szewei%20ft.pdf; http://ir.unimas.my/id/eprint/26751/
• Institution: Universiti Malaysia Sarawak

The objective of this study was to compare the water quality of cage culture activities and abandoned cage culture site of Batang Ai Reservoir, Sarawak. The research was done in November 2013 and March 2014. The water quality parameters were recorded at 4 sampling stations which were station 9 (abandoned cage culture site), station 8_0 m, station 8_15 mand station 8_30 m from cage culture at three different depths (subsurface, 10 m and 20 m). The in-situ parameters done such as temperature, dissolved oxygen and pH decreased as depth increased while turbidity and electrical conductivity increased as depth increased. The value of BODs in November 2013 decreased as depth increased where the range was 6.5 mg/L to 9.6 mg/L. Both N02-N and N03-N increased among the stations as depth increased. The concentration of NH3-N decreased as distance from cage culture increased. The highest concentration of TKN recorded was 0.46 mg/L in November 2013. The TP concentration for station 8 and station 9 increased as the depth increased. At 20 m depth of the abandoned cage culture station, the total sulfide concentration (11.46 jlg/L) showed significant difference from depth of station 80m distance from cage culture site (2.36 jlg/L). Therefore, the months, weather, excess load of nutrient from cage culture site and domestic waste likely affected the water quality in the reservoir.