Ecosystems

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Year 7 Ecosystems - For additional resources visit: http://www.iheartscience.net

Transcript of Ecosystems

EcosystemsSarah Jones

Aquatic Ecosystems

Saltwater - open seas, estuaries and saltwater lakes.

Approximately 65% of the Earth's surface is covered by oceans. Tides, currents, waves and wind continuously move the water in the surface layers.

Freshwater - include still water such as lakes and ponds, swamps, and moving water such as springs creeks and rivers.

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Terrestrial Ecosystems

Terrestrial environments vary as a result of topography, climate, availability of water, and human activity.

Examples: rainforest, open forests, mountain tops, deserts, grasslands, farms and cities.

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PopulationA group of living organisms of the same kind living in the same place at the same time.

CommunityOrganisms living together in a particular place.

HabitatThe habitat of an organism is the place where it lives. These can vary in size e.g. desert, under tree bark, within the digestive system of another organism.

Ecosystems will fail if they do not remain in balance.

No community can carry more organisms than its food, water and shelter can accommodate.

Food and territory are often balanced by natural phenomena such as fire, disease, and the number of predators.

Abiotic Factors of Ecosystems

LightWindRainfallTemperature (daily and seasonal)Topography (altitude and depth)Tides, currents and wavesWater (salinity, pH and availability)Substrate (surface on which an organism grows or is attached)Space and shelterOxygen

Biotic Factors of Ecosystems

Availability of foodNumber of competitorsAvailability of matesNumber of predatorsDisease causing organisms

Limiting factors - anything that makes it difficult for a species to live and grow, or reproduce in its environment.