. 1.) the progression of structural and compositional changes in ecosystems. Ecologists have debated whether the succession is a community process or the product of individual species interacting with each other and their environment 2.) are initiated on new substrates, such as a new volcanic island, a new sandbar in a river, or rubble fields at the foot of a receding glacier. 3.) involve the recovery of vegetation on established soils from land abandonment and from disturbances such as wildfires, hurricanes, or human alterations to vegetation 4.) are regions of Earth that have similar climates and other abiotic (non-living) factors such as elevation, humidity, and soil type and 6.) There are two basic categories of communities: 5.)​