7.10 C Ecological Succession

Both primary and secondary succession begin with pioneer species that -

• change the area and make it safer from predatory organisms

• invade the area so that new organisms cannot be established

• modify the area and allow larger and more complex organisms to appear

• use up all the existing resources and prevent establishment of non-native organisms

Some students take care of a vegetable garden. When it is time to plant in the spring, the students leave part of the garden empty in order to observe ecological succession. Which of these most likely occur first?

• Development of topsoil

• Growth of weeds and grasses

• Growth of trees and shrubs

• Development of a stream