Environmental Factors in Freshwater Systems

The amount of dissolved oxygen in freshwater decreases as temperature increases. Decomposition of dead plants and animals also reduces oxygen levels as oxygen is used during the process.

The types and amounts of salts in freshwater are primarily determined by the geology of the surrounding land. Salts are often carried into the water by soil erosion.

Calcium and magnesium bicarbonates are the most common salts found in freshwater. These salts are often formed by the interaction of carbon dioxide with water and rocks.

Freshwater organisms can be classified based on their role in the food chain or energy chain.

Producer organisms in freshwater environments are those that make their own food, such as plants and photosynthetic microorganisms.

Consumer organisms in freshwater environments are those that eat other organisms to obtain energy, including secondary producers, plant-eaters, predators, and parasites.

Saprophytic organisms, also known as decomposers, break down dead organic matter in freshwater environments. These organisms play a vital role in recycling nutrients.

Benthic organisms live on or in the bottom sediments of freshwater environments. They include filter feeders, such as oysters, and sediment feeders, such as gastropods.

The range of temperatures that aquatic organisms can tolerate is typically narrow, making temperature changes a significant factor affecting their survival. Changes in temperature can lead to shifts in water masses, altering water layers and density.

Suspended materials, like silt, affect how far light can penetrate water. Transparency in water is crucial for plant growth and the entire food chain.

The Secchi disk is a simple device used to measure the transparency of water. It was invented by an Italian scientist in 1865.

Water currents influence the movement of nutrients, gases, and small organisms in aquatic environments. They are vital for the survival of organisms, especially those living in rivers and streams.

Dissolved oxygen is essential for aquatic life. Its concentration is a key indicator of water quality and pollution levels.

In marine environments, both oxygen and carbon dioxide play significant roles in the survival of aquatic organisms.

The amount of dissolved oxygen in water is often used to assess the health of the environment.

Environmental pollution is a major concern, and measuring dissolved oxygen levels is a critical way to monitor the health of our water resources.