What term describes a series of predictable and orderly changes within an ecosystem over time?

The term that describes a series of predictable and orderly changes within an ecosystem over time is "succession." In ecological terms, succession refers to the gradual process through which ecosystems change and develop over time, typically following a disturbance or the creation of a new habitat.

There are two main types of succession: primary succession, which occurs in lifeless areas where soil has not yet formed (such as after a volcanic eruption), and secondary succession, which happens in areas where a disturbance has destroyed an existing ecosystem but soil remains (such as after a forest fire). During these processes, species gradually colonize and modify the environment, leading to changes in community structure and composition until a stable ecosystem, known as a climax community, is reached.

Understanding succession is vital for grasping how ecosystems respond to changes and recover from disturbances, making it a fundamental concept in ecology.