What role do wetlands play in water purification?

Wetlands play a crucial role in water purification by filtering out pollutants and absorbing excess nutrients from the water.

Wetlands, often referred to as 'nature's kidneys', are vital in maintaining the quality of water. They act as natural water purifiers by trapping sediments and pollutants that could otherwise contaminate water bodies. Wetlands are rich in vegetation and microbial life, which help in breaking down various pollutants. They absorb excess nutrients like nitrogen and phosphorus, which can cause harmful algal blooms in water bodies if present in high quantities.

The process of water purification in wetlands is a combination of physical, chemical and biological processes. The physical process involves the trapping of sediments and particulate matter in the water. As water flows through a wetland, the speed of the water decreases, allowing these particles to settle down. This process is known as sedimentation.

The chemical process involves the absorption and transformation of various pollutants. Wetlands are rich in anaerobic bacteria, which can convert harmful substances like nitrates into harmless nitrogen gas through a process called denitrification. Wetland plants also play a significant role in this process. They absorb excess nutrients from the water for their growth, thereby reducing the nutrient load in the water.

The biological process involves the breakdown of organic pollutants by microorganisms present in the wetland. These microorganisms use organic pollutants as a source of energy and in the process, convert them into less harmful substances.

Wetlands also play a role in the removal of heavy metals from the water. Certain types of wetland plants are known to absorb heavy metals like lead and mercury from the water, thereby reducing their concentration.

In conclusion, wetlands play a multifaceted role in water purification. They not only filter out sediments and pollutants but also absorb excess nutrients and heavy metals, thereby maintaining the quality of water. This makes the conservation of wetlands crucial for maintaining the health of our water bodies.