End Show Slide 1 of 39 Tues Sept 10/ Wed Sept 11 AGENDA Stamp Homework: Nutrient Cycles Succession Lab: Intro and Observations Video: The Battle at Kruger National Park Notes: What shapes an ecosystem? HOMEWORK Read pg in textbook. Complete Symbiosis activity Copyright Pearson Prentice Hall

End Show Slide 2 of 39 Copyright Pearson Prentice Hall 4-2 What Shapes an Ecosystem?

End Show 4-2 What Shapes an Ecosystem? Slide 3 of 39 Copyright Pearson Prentice Hall Biotic and Abiotic Factors Ecosystems are influenced by a combination of biological and physical factors. Biotic – biological factors

End Show 4-2 What Shapes an Ecosystem? Slide 4 of 39 Copyright Pearson Prentice Hall Biotic and Abiotic Factors Physical, or nonliving, factors that shape ecosystems are called abiotic factors. Abiotic factors include: temperature precipitation humidity wind nutrient availability soil type sunlight

End Show 4-2 What Shapes an Ecosystem? Slide 5 of 39 Copyright Pearson Prentice Hall Biotic and Abiotic Factors How do biotic and abiotic factors influence an ecosystem?

End Show 4-2 What Shapes an Ecosystem? Slide 6 of 39 Copyright Pearson Prentice Hall Biotic and Abiotic Factors The area where an organism lives is called its habitat. A habitat includes both biotic and abiotic factors.

End Show 4-2 What Shapes an Ecosystem? Slide 7 of 39 Copyright Pearson Prentice Hall The Niche A niche is the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions. * No two species can share the same niche in the same habitat.

End Show 4-2 What Shapes an Ecosystem? Slide 8 of 39 Copyright Pearson Prentice Hall Community Interactions What interactions occur within communities?

End Show 4-2 What Shapes an Ecosystem? Slide 9 of 39 Copyright Pearson Prentice Hall Community Interactions Competition Competition occurs when organisms of the same or different species attempt to use an ecological resource in the same place at the same time. A resource is any necessity of life, such as water, nutrients, light, food, or space.

End Show 4-2 What Shapes an Ecosystem? Slide 10 of 39 Copyright Pearson Prentice Hall Community Interactions Direct competition in nature often results in a winner and a loser—with the losing organism failing to survive. The competitive exclusion principle states that no two species can occupy the same niche in the same habitat at the same time. What is the algae in this picture competing with?

End Show 4-2 What Shapes an Ecosystem? Slide 11 of 39 How do algal blooms affect ecosystems? 1.An algal bloom is caused by a rapid influx of nutrients (i.e..-fertilizer) into a water ecosystem. 2.The algae grows and chokes out the light plants use to photosynthesize. 3.Plants die creating a large amount of decaying matter. 4.Bacteria invade the area to decompose the plant matter. 5.The bacteria use large amounts of oxygen, reducing the amount available for other organisms such as fish. 6.Fish and other organisms that live in the ecosystem begin to die. Copyright Pearson Prentice Hall

End Show 4-2 What Shapes an Ecosystem? Slide 12 of 39 Copyright Pearson Prentice Hall Community Interactions The distribution of these warblers avoids direct competition, because each species feeds in a different part of the tree. Yellow-Rumped Warbler Bay-Breasted Warbler Feeding height (m) Cape May Warbler

End Show 4-2 What Shapes an Ecosystem? Slide 13 of 39 Copyright Pearson Prentice Hall Community Interactions Predation An interaction in which one organism captures and feeds on another organism is called predation. The organism that does the killing and eating is called the predator, and the food organism is the prey.

End Show 4-2 What Shapes an Ecosystem? Slide 14 of 39 Copyright Pearson Prentice Hall Community Interactions Symbiosis Any relationship in which two species live closely together is called symbiosis. Symbiotic relationships include: mutualism commensalism parasitism

End Show 4-2 What Shapes an Ecosystem? Slide 15 of 39 Copyright Pearson Prentice Hall Community Interactions Mutualism: both species benefit from the relationship. Commensalism: one organism benefits and the other is neither helped nor harmed. Parasitism: one organism lives on or inside another organism and harms it.