Explanation:

Any practice that affects the equilibrium of an aquatic environment may alter the temperature of that environment and subsequently cause thermal pollution. It may come in the form of warm or cold water being dumped into a lake, river, or ocean.
In layman’s terms, thermal pollution is when an industry or other human-made organization takes in water from a natural source and either cools it down or heats it up. They then eject that water back into the natural resource, which changes the oxygen levels and can have disastrous effects on local ecosystems and communities.
Thermal pollution is defined as sudden increase or decrease in temperature of a natural body of water which may be ocean, lake, river or pond by human influence. This normally occurs when a plant or facility takes in water from a natural resource and puts it back with an altered temperature. Usually, these facilities use it as a cooling method for their machinery or to help better produce their products.
Source of thermal pollution
•Volcanic eruption or geothermal activities below the ocean.
•Heated waste water produces from coal-based power plant,
•Textile paper and pulp industry.
•Deforestation and decreasing tree coverage and Soil erosion.
Ecological Impact of thermal Pollution
Decrease in dissolved oxygen: warmer water increases the rate of decomposition of organic matter, resulting in higher rate of decreasing the depleted oxygen. Threat to temperature sensitive organism for instance, stenothermic organism can survive in a narrow range of temperature any variation in temperature is detrimental to their survival. It disrupts the stability of food chain and alters the ecology of marine organisms.