ENVS 1126 Chapter : LBN Chapter 5
Document Summary
Ecosystems are complex systems: ecosystems respond to disturbances such as volcanoes, fires, volcanoes and humans, disturbance: natural or human-induced event that interrupts ecological succession and creates new conditions on site, ecosystems also undergo processes: Photosynthesis, respiration, energy flow: humans rely on ecosystems and assign value to ecosystem goods and services, ecosystem sustainability is threatened by human use. Characteristics of ecosystems: ecosystems contain communities of interacting species (biota) and their abiotic factors. Species" presence is due to climate, history and humans. Range of tolerance and limiting factors control species distributions. There are predictable patterns to ecosystem distribution around the world: biomes: ecosystems having similar vegetation and climactic conditions. Trophic levels: during photosynthesis, plants use light energy, Not all e and nutrients go to higher trophic levels: food web: interconnection of food chains to form complex feeding relationships. Trophic levels show movement of e and materials: autotrophs: produce organic material from inorganic matter by using an external e source.
