Aquatic Ecosystems Quiz

What is the primary characteristic that distinguishes freshwater ecosystems from marine ecosystems?

• Higher biodiversity

• Presence of aquatic plants

• Salt content less than 1%

• Presence of coral reefs

Which zone in a lake is known for being well-lit and supporting a variety of freshwater fish?

• Littoral zone

• Benthic zone

• Limnetic zone

• Profundal zone

Which type of lake is characterized by being nutrient-poor with limited vegetation?

• Eutrophic lake

• Mesotrophic lake

• Oligotrophic lake

• Hypereutrophic lake

What is a significant change observed from the headwaters to the mouth of a river?

• Increase in oxygen levels

• Decrease in sediment levels

• Increase in temperature and sediment levels

• Decrease in biodiversity

Which human activity is NOT mentioned as impacting freshwater wetlands?

• Building dams

• Deforestation

• Constructing canals

• Agricultural drainage

What percentage of the Earth's surface is covered by marine ecosystems?

• 80%

• 70%

• 60%

• 50%

Which zone in the ocean is known for having the highest levels of photosynthesis?

• Euphotic zone

• Abyssal zone

• Mesopelagic zone

• Benthic zone

What is the primary role of estuaries in marine ecosystems?

• Providing habitat for coral reefs

• Acting as carbon sinks

• Serving as nurseries for juvenile marine life

• Reducing salinity levels

Which of the following is a major threat to coral reefs?

• Increased oxygen levels

• Decreased salinity

• Ocean warming

• Increased biodiversity

What is the function of mangroves in coastal ecosystems?

• Increasing salinity levels

• Providing timber for construction

• Reducing high salinity levels

• Supporting coral reef growth