Vertical distribution of hydrogen sulfide in the water of Tasik Kenyir, Terengganu

Abstract

This study was conducted at Tasik Kenyir. Tasik Kenyir is the biggest man made lake in Southeast Asia. For depth below thanlOm, anaerobic condition was found where the dissolve oxygen is between 0-3mg/l. There was a drastic temperature changes in the water profile at 1 Om below. During monsoon, the temperature gradient from the surface to the bottom is 3-4°C. Its mean, monsoon does not effect the thermocline. However, it does increase the aerobic layer down to 25m. This is due to heavy precipitation during monsoon. Hydrogen sulfide level in Tasik Kenyir is 16.84 mg/1 in the hypolimnion and the DO was reached less than 1 mg/1. Hydrogen sulfide not naturally come from lake or sg. Como, but it is due to cage culture at lake.