Estuaries and Ecosystems - Grade 9

Flashcards for reviewing and understanding key concepts related to estuaries and ecosystems.

What is an estuary?

A partially enclosed body of water formed where a river flows into an ocean.

What is a watershed?

A region of land that drains into a river, a river system, or another body of water.

What is the littoral zone?

The area located between the high and low water marks along the shoreline.

What is the limnetic zone?

The open water located farther out from shore.

What is the benthic zone?

The lake or pond bottom, where less sunlight reaches.

Why are estuaries referred to as dynamic environments?

Because they are characterized by a mixture of fresh and salt water and support a variety of marine life.

What distinguishes estuaries from other marine environments?

The mixture of fresh water from rivers and salt water from the ocean.

How do estuaries compare to tropical rain forests and coral reefs in terms of productivity?

Estuaries are highly productive ecosystems comparable to tropical rain forests and coral reefs.

What is the role of phytoplankton and zooplankton in estuaries?

They support a variety of species, serving as a primary food source for fish.

Why are estuaries called nurseries of the sea?

Because many aquatic species lay eggs in estuaries, and their young mature there before venturing into the ocean.

What adaptations do organisms in estuaries have to cope with changing salinities?

Some organisms have glands that remove excess salt from their bodies.

List five types of ecosystems that can be found in estuaries.

Salt marshes, mud flats, open water, mangrove forests, tidal pools.

How can the removal of estuaries affect coastal areas?

It makes coastal areas more vulnerable to flood damage from storms such as hurricanes.

What defines the characteristics of rivers and streams?

The speed of flow, the type of river bottom, and seasonal water level changes.

How do human activities affect rivers?

By damming rivers or draining water for irrigation or drinking.

What factors determine the variety of freshwater organisms in a body of water?

Water temperature, oxygen levels, pH, and water flow rate.

What adaptations do trout have that allow them to thrive in fast-moving rivers?

They have streamlined bodies that allow them to swim against strong currents.

How do stoneflies avoid being swept away in fast-running water?

They use hooks on their bodies to attach themselves to solid surfaces.

What is the difference between the littoral zone and the limnetic zone?

Littoral zone is near shore, while limnetic zone is the open water farther from shore.

What types of plants can be found in the littoral zone?

Emerged plants, floating plants, and terrestrial plants.

What is the euphotic zone?

The upper layer of water in lakes where sunlight penetrates and photosynthesis occurs.

What organisms live in the benthic zone?

Decomposers, such as bacteria, live in the mud and sand of the benthic zone.

How do barrier islands benefit estuaries?

They protect estuary species from storms and strong currents.

What role do decomposers play in estuaries?

They decompose dead organic matter and return vital nutrients to the ecosystem.

In what way is the life cycle of many fish linked to estuaries?

Estuaries serve as breeding and nursery grounds for many fish species.

What are the main threats to estuarine ecosystems?

Pollution, habitat destruction, and climate change.

What is a tidal pool?

A coastal water body that remains in place even at low tide.

How do salinity changes challenge organisms in estuaries?

Organisms must adapt to varying salt levels, which can affect their survival.

What is the significance of detritivore communities in estuaries?

They help decompose organic matter, recycling nutrients within the ecosystem.

What is the function of wetlands within the estuarine ecosystem?

They provide critical habitat for wildlife and help filter pollutants.

How does photosynthesis support the food web in estuaries?

Photosynthetic organisms convert sunlight into energy, forming the base of the aquatic food web.

What role do human activities play in the health of estuaries?

Human development can lead to pollution and habitat loss, impacting ecosystem health.

Why is it important to protect estuarine environments?

They are critical for biodiversity and provide essential resources for humans.

Describe the physical adaptations of plants found in estuaries.

Plants may have specialized root systems to anchor in unstable substrates and tolerate salinity.

How do seasonal changes affect river ecosystems?

Seasonal changes can alter flow rates, temperatures, and nutrient levels, impacting aquatic life.

What is the impact of nutrient runoff on estuarine ecosystems?

It can lead to algal blooms, which reduce oxygen levels and harm marine life.

Why are estuaries considered biodiversity hotspots?

They provide diverse habitats for various species and support complex food webs.

What adaptations do mangroves have to survive in brackish waters?

They have specialized roots that help filter salt and stabilize shoreline.

Define the term 'bioindicators' in the context of estuarine health.

Organisms that signal the health of an ecosystem, often used to monitor environmental conditions.

What human interventions can protect estuary habitats?

Restoration projects, pollution control measures, and sustainable development practices.

How does climate change threaten estuaries?

It can cause sea level rise, altering salinity and impacting habitat availability.