20. Communities and Ecosystems

If a forest contains 47,000 kg of plant material, how many kg of tertiary consumers can it support?

Match each of the following species to their role in their respective communities:

Beaver: builds dams in rivers/lakes, significantly altering habitats in the area.

Ochre Sea Star: preys on mussels, preventing them from overpopulating intertidal zones & dominating the habitat.

Red Mangrove Tree: stabilizes shorelines by reducing erosion, provides nurseries for fish in coastal regions.

Consider an ocean community where corals are the most abundant species, where they "build" new habitats using calcium carbonate deposits, creating a coral reef. Which of the following terms can be applied to corals in this community?

Which of the following could be characterized as top-down control in a community?