Zones of Pollution in a River-system

A polluted river undergoing self-purification can be divided into four zones:

• Zone of degradation
• Zone of active decomposition
• Zone of recovery
• Zone of clear water

Here are some questions and answers about the zones of pollution in a river:

• What are the four zones of pollution in a river?
• What is the most polluted zone in a river?
• What is the process of reoxygenation?
• How does a river recover from pollution?

Here are the answers to the questions above:

• The four zones of pollution in a river are the zone of degradation, the zone of active decomposition, the zone of recovery, and the zone of clear water.
• The most polluted zone in a river is the zone of active decomposition.
• Reoxygenation is the process of adding oxygen to water. It occurs when oxygen from the atmosphere dissolves into the water.
• A river recovers from pollution through a process called self-purification. This process involves the decomposition of organic matter by bacteria and other microorganisms.