spec points

• ecosystems, which range in size, are dynamic and are influenced by both biotic and abiotic factors

• to include reference to a variety of ecosystems of different sizes (e.g. a rock pool, a playing field, a large tree) and named examples of biotic and abiotic factors.

intro

• made up of all living organisms that interact with one another in a defined area known as the community, and also the physical factors present in that region

  • e.g. rock pool, paying field, tree, the entire biosphere of earth, tiny colony of bacteria

• both biotic + abiotic factors control distribution + abundance of organisms in habitat

  • e.g. predators and pathogens, light levels and temperature

dynamic ecosystems

• Ecosystems are dynamic (ie constantly changing).
  Populations in the community fluctuate depending on many factors, e.g. Predation, seasonal changes etc.

• All populations are linked to all other populations in the ecosystem in some way as well as to the habitat in which they live.

• Changes in one part of an ecosystem are likely to cause changes in another part!