ENERGY FLOW IN ECOSYSTEMS CHAPTER 5 SECTION 1
Warm-up • How is energy transferred fro one organism to another? • Why should forest rangers let some forest fires burn? • Write down three plants or animals and the animals that eat them. • Also write down any plants that you know eat animals.
Did you know this? • Some natural forest fires clear land of brush and deadwood, cause the growth of new vegetation for animals to eat, and kill vegetation that competes with native plant species.
Life depends on the Sun Key Terms Photosynthesis
From producers to consumers Key Terms Autotrophs, Producers Heterotrophs, consumers Do you think Clover plant is important for coyote? How does the coyote depend on the Sun?
An exception to the rule: Deep-ocean Ecosystems • http://www.extremescience.com/deep-sea-vents-video.htm • Organisms that live in hydrothermal vent: clams, worms, mussels, sponges, barnacles. These deep-ocean communities live in total darkness, where photosynthesis cannot occur. Bacterial live in these organisms and make use of hydrogen sulfide to make their own Food. Hydrogensulfide is present in hot water that escapes from cracks in the ocean Floor. These bacteria are eaten By other organisms and thus Support a ecosystem
What eats what? bcs.whfreeman.com
Key terms • Herbivores • Carnivores • Omnivores • Decomposers/detritivores • Role of decomposers: They break down dead organic matter and allow the nutrients in the rotting material to return to the soil, water, and air. Example bacteria and fungi.
Math skill • How many calories are there in 30lbs of salmon if each pound of salmon = approx.654 cal? • How many calories are there in 66 lbs of blueberries if each pound of blueberries = approx.261 cal? • Do not use calculators.
Answers • 30lbs x 654 = 19620 cal • 66lbs x 261 cal = 17226 cal
Energy transfer • Each time one organism eats another organism, a transfer of energy occurs. We can trace the transfer of energy as it travels through an ecosystem by studying food cahins, food webs, and trophic levels.
Food web Key Terms Trophic level
DDT in an aquatic Food Chain Read case study in Page number 120
How energy loss affects an ecosystem • There are fewer organisms at the higher trophic levels. For example, zebras and other herbivores outnumber lions on the African Savanna by about 100 to 1. • The loss of energy from trophic level limits the number of trophic levels in an ecosystem. Ecosystems rarely have more than four or five trophic levels because the ecosystem does not have enough energy left to support higher levels.