Factors affecting Dissolved Oxygen in Streams

Dissolved oxygen in streams is affected by various factors such as temperature, atmospheric pressure, water flow, photosynthesis, respiration, and decomposition of organic matter.

Temperature
The solubility of oxygen in water decreases as the temperature of water increases. This means that warm water can hold less dissolved oxygen than cold water. Therefore, when the temperature of the stream increases, the dissolved oxygen decreases.

Atmospheric Pressure
Atmospheric pressure affects the solubility of oxygen in water. When the atmospheric pressure is low, the solubility of oxygen is also low, and vice versa. Therefore, low atmospheric pressure can result in low dissolved oxygen levels in the stream.

Water Flow
Water flow has an impact on the amount of dissolved oxygen in the stream. Generally, fast-flowing water has high dissolved oxygen levels because it can mix with air more efficiently. Slow-moving water, on the other hand, has low dissolved oxygen levels because it has less exposure to the air.

Photosynthesis
During photosynthesis, plants release oxygen into the water. Therefore, during the day when there is sunlight, photosynthesis is more active, resulting in high dissolved oxygen levels in the stream. This means that the maximum dissolved oxygen levels are at noon.

Respiration
Respiration is the process by which organisms consume oxygen and release carbon dioxide. This process lowers the amount of dissolved oxygen in the stream. Organisms that live in the water, such as fish, consume oxygen through respiration.

Decomposition of Organic Matter
The decomposition of organic matter can consume dissolved oxygen in the stream. Microorganisms that break down organic matter require oxygen to carry out their metabolic processes. Therefore, when there is a high concentration of organic matter, the dissolved oxygen levels in the stream can decrease.

Conclusion
From the above discussion, it is clear that the dissolved oxygen in streams is maximum at noon. During the day, photosynthesis is more active, resulting in high dissolved oxygen levels in the stream. However, as the temperature increases, the dissolved oxygen levels decrease. Respiration and decomposition of organic matter can also consume dissolved oxygen in the stream. Therefore, it is essential to maintain a balance between these factors to ensure that the dissolved oxygen levels in the stream are suitable for the survival of aquatic organisms.