Ecosystems Individuals populations and communities are ecological levels

Ecosystems Individuals, populations and communities are ecological levels which refer to organisms living in the same habitat - an ECOSYSTEM takes into account both the living (biotic) & non-living (abiotic) components of the environment = a community interacting with the non-living components of the habitat

Trophic Relationships Living organisms need energy in order to survive: • Producers use the sun + abiotic elements to make their own food (= autotroph) • Consumers must obtain energy from biotic sources by eating other organisms (= heterotroph)

Food Chains / Food Webs Food chains/webs are used to show the trophic levels of producers and consumers in an ecosystem The arrows show the direction of energy along the chain The sun is the primary source of energy on earth

Trophic Levels Tertiary Consumer / Third Order Secondary Consumer /Second Order Primary Consumer / First Order Consumer Producer Decomposer Omnivores are consumers which occupy more than one trophic level in the same food web (they eat both producers and consumers) Scavenger

Two categories of matter Category Description Examples Matter that is not necessarily Water, mineral Inorganic matter produced by salts living organisms Matter that is Organic matter created by living Proteins, lipids organisms

Disturbances • an event that is damaging to an ecosystem • two types: Natural & Human

Another kind of disturbance: Invasive species – a species that outcompetes similar organisms in its habitat, and is uncontrolled in its takeover of this habitat. https: //www. edumedia-sciences. com/en/media/265 -invasive -plants

Chemical Recycling in an Ecosystem p. 324