The term for a sudden change in the environment that affects ecosystems is disturbance. Disturbances can occur due to natural events, such as wildfires or floods, or human activities, such as deforestation and pollution. These events can drastically alter habitat structures and the availability of resources, leading to shifts in community composition and species dynamics. Understanding disturbances is essential for managing and conserving biodiversity, as they can have long-term ecological impacts on affected areas.