Question

At a particular segment of a river near a sugar factory, the BOD is much higher than the normal level. What is it indicative of? What will happen to the living organisms in this part of the river?

Answer 1

It indicates the addition of lot of organic matter; microorganisms involved in the biodegradation of organic matter in the water body consume a lot of oxygen and as a result, there is a sharp decline in the dissolved oxygen content downstream from the point of addition of effluent from the factory. This causes mortality of fish and other aquatic organisms.