What causes water discoloration due to decaying vegetation?

Discoloration of water due to decaying vegetation is primarily caused by organic substances known as humic substances. These humic substances are the result of the breakdown of plant materials and other organic materials in the water. When vegetation decays, it releases various organic compounds into the water. Humic substances contribute to the brown or yellowish coloration observed in such water bodies.

These compounds not only affect the aesthetic quality of water but can also have implications for water treatment processes. They can interact with chlorine during disinfection, leading to the formation of potentially harmful by-products. Understanding the role of humic substances is crucial for effective water treatment, particularly when dealing with raw water that is impacted by vegetation decay.

Other factors like algae growth can also affect water color but typically do not originate from the decomposition of vegetation itself. Pesticide runoff and mineral deposits have distinct causes and effects unrelated to the decay of plant matter.