Question

Increase in BOD of the water reservoir is due to
(a)Algae
(b)Soil
(c)Moss
(d)Waste product

Answer 1

Water bodies do include a small amount of dissolved oxygen, which is needed for both fishes and other aquatic organisms to go through aerobic respiration. Biochemical oxygen demand (BOD) commonly illuminates how much oxygen is needed to break down organic matter in water.

Complete answer:
BOD calculates the amount of oxygen absorbed by microorganisms for the action of decomposition of the organic matter in the water bodies. In some water bodies, organic matter is a huge origin of oxygen gas. These organic matters include sewage and other pollutants present within the water bodies. The higher the BOD, the less is the dissolved oxygen present for the aerobic animals like fishes and other aquatic ecosystems. The BOD is consequently a calculable measure of the organic pollution of water bodies. The primary reason for treating wastewater preceding its discharge into a water resource is to lower its BOD level (the demand for oxygen). It determines the quantity of organic matter present in soils, sewages, sediment, garbage, sludge, etc.

Additional Information: Oxygen utilized in the decomposition process lowers other aquatic organisms of the oxygen they require to live. If dissolved oxygen concentrations drop below 5 parts per million (ppm), fish are going to be unable to measure for very long. This can occur within the sort of organic pollution for sources like domestic sewage, tank leakage, and fertilizer runoff, or might be within the sort of inorganics from domestic or industrial sources.
So, the correct answer is ‘Waste product’.

Note: BOD is utilized in the medicinal and pharmaceutical industries to test the oxygen utilization of cell cultures. It indicates the quantity of organic pollution present in an aquatic ecosystem. It also calculates the chemical oxidation (COD) of inorganic matter. BOD is also used in wastewater treatment to demolish and decompose organic wastes by aerobic organisms. The biochemical oxygen demand also determines the speed of respiration in living beings.