Marine Ecosystems: Neritic Waters, Seagrass, Coral Reefs, Intertidal Zones, Estuaries, Saltmarsh & Mangroves

What are the reasons for high productivity in shallow subtidal ecosystems?

Shallow subtidal ecosystems have high productivity due to ample sunlight, nutrient availability, and the presence of diverse primary producers.

Compare the three phyla of macroalgae based on pigments.

Green algae (Chlorophyta) contain chlorophyll a and b, brown algae (Phaeophyta) contain chlorophyll a and c along with fucoxanthin, and red algae (Rhodophyta) contain chlorophyll a and phycoerythrin.

What are the basic ecological roles of macroalgae?

Macroalgae provide habitat, food, and oxygen; they also play a role in nutrient cycling and carbon fixation.

Describe the habitat and adaptations of kelp forests.

Kelp forests develop in nutrient-rich, shallow waters; kelp has adaptations like gas-filled bladders for buoyancy and a flexible structure to withstand wave action.

What are the dominant invertebrates found in kelp forest ecosystems?

Dominant invertebrates include sea urchins, crabs, and various mollusks.

What factors influence the vertical zonation of kelp forests?

Vertical zonation in kelp forests is influenced by light availability, water temperature, and competition among species.

What is a generalized food web of a kelp forest?

A kelp forest food web includes primary producers (kelp), primary consumers (herbivorous fish, sea urchins), secondary consumers (predatory fish), and top predators (sea otters, sharks).

What are the morphological characteristics of seagrasses?

Seagrasses have elongated leaves, root systems for anchorage, and adaptations for underwater life, such as reduced air spaces.

What ecological roles do seagrasses play?

Seagrasses stabilize sediments, improve water clarity, provide habitat for marine organisms, and contribute to nutrient cycling.

What are the dominant herbivores in seagrass ecosystems?

Dominant herbivores include manatees, sea turtles, and certain fish species.

What are the basic ecological roles of reef-building corals?

Reef-building corals provide habitat, promote biodiversity, and contribute to the structure of coral reef ecosystems.

How do corals reproduce?

Corals reproduce through both sexual (spawning) and asexual (budding) methods.

Why are coral reefs productive despite nutrient-poor waters?

Coral reefs are productive due to symbiotic relationships with zooxanthellae, which provide energy through photosynthesis.

What factors determine zonation in intertidal zones?

Factors include tidal action, wave exposure, and the ability of organisms to withstand desiccation and temperature changes.

What adaptations do intertidal organisms have?

Adaptations include the ability to cling to surfaces, tolerate varying salinity, and withstand exposure to air.

What are the differences between soft-sediment and rocky intertidal zones?

Soft-sediment zones have more stable sediments and lower biodiversity, while rocky zones have higher competition and more diverse organisms.

Define an estuary.

An estuary is a coastal area where freshwater from rivers meets and mixes with saltwater from the ocean.

What are the types of estuaries based on formation?

Estuaries can be classified as coastal plain, tectonic, and bar-built estuaries.

What are saltmarshes and mangroves?

Saltmarshes are coastal wetlands dominated by herbaceous plants, while mangroves are coastal ecosystems characterized by salt-tolerant trees.

What is detritus and its role in food webs?

Detritus is decomposed organic material that serves as a foundation for food webs, providing nutrients for primary producers.