What is the term for the gradual and orderly process of change in an ecosystem?

The term for the gradual and orderly process of change in an ecosystem is "succession." This process describes how ecosystems develop over time, following disturbances such as fire, flooding, or human activities. Succession can occur in two primary forms: primary succession, where new land is formed (such as after a volcanic eruption), and secondary succession, where an existing ecosystem is disturbed but the soil and some organisms remain (such as after a forest fire).

Succession involves a series of stages where different species colonize an area, with each group of organisms contributing to changes in the environment, thus paving the way for subsequent species to thrive. It ultimately leads to a stable community known as a climax community, illustrating the dynamic nature of ecosystems and their ability to recover and evolve. This concept emphasizes the interconnectedness of organisms and their environments, showcasing how ecosystems can change and adapt over time.

The other terms do not specifically refer to this process. An estuary is a coastal area where freshwater from rivers meets and mixes with saltwater from the ocean. Extinction refers to the end of an organism or a species, and aquatic pertains to environments related to water.