Aquatic Ecosystem Factors Assessment

The video discusses key water quality parameters: pH, temperature, dissolved oxygen, and nitrates. It explains how pH levels affect aquatic life, the impact of temperature on cold-blooded organisms, the importance of dissolved oxygen for water health, and the role of nitrates in eutrophication. The interrelation of these factors and their effects on aquatic ecosystems are highlighted.

What does a pH value of 7 indicate about water?

• It is basic.

• It is acidic.

• It is highly alkaline.

• It is neutral.

Which pH range is generally considered optimal for most fish?

• 3.8 to 5.0

• 6.5 to 8.2

• 9.0 to 11.0

• 4.0 to 6.0

What is the effect of water temperature on cold-blooded animals?

• They can survive at any temperature.

• They thrive in temperatures below zero degrees Celsius.

• They have an optimal temperature range for survival.

• They prefer temperatures above 36 degrees Celsius.

Which factor does NOT affect water temperature?

• Depth of the water

• Amount of sunlight

• Color of the water

• pH level of the water

At what temperature will rainbow trout stop growing?

• 8 degrees Celsius

• 15 degrees Celsius

• 19 degrees Celsius

• 24 degrees Celsius

How does temperature affect dissolved oxygen levels in water?

• Higher temperatures decrease dissolved oxygen.

• Lower temperatures decrease dissolved oxygen.

• Higher temperatures increase dissolved oxygen.

• Temperature has no effect on dissolved oxygen.

What is the minimum dissolved oxygen level required for a healthy fish population?

• 2.0 parts per million

• 6.0 parts per million

• 4.0 parts per million

• 9.0 parts per million

What is a common source of nitrates in waterways?

• Natural decomposition

• Household detergents

• Fertilizers

• Industrial waste

What is eutrophication?

• A decrease in water temperature

• A method of water purification

• A process of increasing dissolved oxygen

• Rapid algae growth reducing oxygen levels

How do nitrates affect aquatic plant growth?

• They promote plant and bacterial growth.

• They have no effect on plants.

• They reduce bacterial growth.

• They inhibit plant growth.