13 2 Biotic and Abiotic Factors Objective Students
13. 2 Biotic and Abiotic Factors Objective: Students will know that an ecosystem includes both biotic and abiotic factors AND that changing one factor in an ecosystem can affect many other factors.
13. 2 Biotic and Abiotic Factors KEY CONCEPT Every ecosystem includes both living (biotic) and nonliving (abiotic) factors.
13. 2 Biotic and Abiotic Factors • Biotic factors are living things. – plants – animals – fungi – bacteria plants
13. 2 Biotic and Abiotic Factors • Abiotic factors are nonliving things. – moisture – temperature – wind – sunlight – soil sunlight moisture
13. 2 Biotic and Abiotic Factors Every ecosystem contains biotic and abiotic factors • List the biotic and abiotic factors in this picture • Share with your neighbors
13. 2 Biotic and Abiotic Factors • Biodiversity is the assortment, or variety, of living things in an ecosystem. – Rain forests have more biodiversity than other locations in the world, but are threatened by human activities. (50% of the world’s plant and animals species are here)
13. 2 Biotic and Abiotic Factors • Biodiversity has to do with: Number of species NOT Population number
13. 2 Biotic and Abiotic Factors • Extinctions lower biodiversity!!!
13. 2 Biotic and Abiotic Factors • A keystone species is a species that has an unusually large effect on its ecosystem. Ex: A beaver • Their removal from the ecosystem may cause a ripple effect felt across an entire ecosystem keystone
13. 2 Biotic and Abiotic Factors • By felling trees to construct dams, Beavers: – Change free flowing streams into ponds, wetlands, and meadows – Lead to an overall increase in biodiversity creation of wetland ecosystem increased waterfowl Population increased fish population keystone species nesting sites for birds
13. 2 Biotic and Abiotic Factors • More variety of fish- Fish attract birds • Insects inhabit pond and dead trees along the shore. Insects attract birds • Animals that prey on birds are attracted to the pond creation of wetland ecosystem increased waterfowl Population increased fish population keystone species nesting sites for birds
13. 2 Biotic and Abiotic Factors Other keystone species
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