Tag: water pollution and its control

Biochemical oxygen demand (BOD) is the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period. 

Biochemical oxygen demand is a measure of the quantity of oxygen used by microorganisms (e.g., aerobic bacteria) in the oxidation of organic matter. Natural sources of organic matter include plant decay and leaf fall. However, plant growth and decay may be unnaturally accelerated when nutrients and sunlight are overly abundant due to human influence. Urban runoff carries pet wastes from streets and sidewalks, nutrients from lawn fertilizers; leaves, grass clippings, and paper from residential areas, which increase oxygen demand. Oxygen consumed in the decomposition process reduces other aquatic organisms of the oxygen they need to live. If dissolved oxygen concentrations drop below 5 parts per million (ppm), fish will be unable to live for very long. This can occur in the form of organic pollution for sources such as domestic sewage, septic tank leakage, and fertilizer runoff, or could be in the form of inorganics from domestic or industrial sources. 

Biochemical oxygen demand (BOD) is the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period. 

Biological oxygen demand (BOD) is one of the most common measures of pollutant organic material in water. BOD indicates the amount of putrescible organic matter present in water. Therefore, a low BOD is an indicator of good quality water, while a high BOD indicates polluted water. The BOD test serves an important function in stream pollution-control activities.

Biochemical oxygen demand (BOD) is the amount of dissolved oxygen needed by aerobic microorganisms to break down organic material present in a given water sample at certain temperature over a specific period of time. Thus, the correct answer is option C.

BOD is abbreviated form of biological oxygen demand. It is the amount of oxygen required by microbes to break down the organic matter present in a certain volume of a sample of water. The amount of BOD in the water is a measure of a number of organic pollutants in the water.

C.O.D. stands for chemical oxygen demand. It is the measurement of the pollution which is based on the chemical decomposition of organic and oxidation of the inorganic contaminants present in dissolved water. It is mainly used against waste water which is contaminated by domestic and industrial wastes.

Biological Oxygen Demand is a measurement of the amount of dissolved oxygen that is used by aerobic microorganisms when decomposing organic matter in water.  It is expressed in milligrams of oxygen consumed per liter of the sample during 5 days of incubation at 20°C and is used to determine the degree of organic pollution of water. Hence when a huge amount of carbon dioxide is added BOD will not be affected. Thus, the correct answer is option C.