DOAM

DOAM (Dissolved Organic Aquatic Matter) refers to organic materials found in aquatic environments that have dissolved into the water column. This matter is crucial for the ecological dynamics of aquatic systems, influencing both the physical and biological processes of water bodies such as lakes, rivers, and oceans.

Composition and Sources

DOAM is primarily composed of a complex mixture of organic compounds, including proteins, lipids, carbohydrates, and various other organic molecules. These compounds originate from several sources:

• Biological production: Aquatic organisms, such as phytoplankton, produce organic matter as a byproduct of photosynthesis and other metabolic activities.
• Decomposition: The breakdown of dead organic material, such as fallen leaves, dead animals, and other biological detritus, contributes to the dissolved organic pool.
• Terrestrial input: Runoff from land can carry organic materials from soils and plants into aquatic systems, particularly after rainfalls or snow melts.

Ecological Importance

DOAM plays a pivotal role in aquatic ecosystems:

• Nutrient cycling: It serves as a source of nutrients for microorganisms. The decomposition of DOAM by bacteria and fungi releases nutrients such as nitrogen and phosphorus, which are essential for aquatic life.
• Energy flow: DOAM is a significant component of the aquatic food web. It provides an energy source for heterotrophic organisms, including bacteria and zooplankton, which in turn are preyed upon by higher trophic levels.
• Water quality: The presence and concentration of DOAM can influence the optical properties of water, such as color and transparency, which affects photosynthesis rates and heat absorption.

Impact on Water Treatment

In the context of human use, DOAM has implications for water treatment processes. High levels of DOAM can lead to problems in drinking water systems, such as:

• Taste and odor issues: Certain organic compounds can impart undesirable flavors or odors.
• Disinfection byproducts: During chlorination, reactions between chlorine and DOAM can form harmful byproducts like trihalomethanes and haloacetic acids, which are potential health risks.

Research and Monitoring

Ongoing research aims to better understand the sources, transformations, and ecological impacts of DOAM. Monitoring programs are essential for managing water quality, particularly in areas used for drinking water or recreational activities.

See Also

• Biogeochemical cycle
• Water pollution
• Aquatic ecosystem