1. Chapter 5 How Ecosystems Work

2. Section 1 - Energy Flow in Ecosystems Life Depends on the Sun Life Depends on the Sun Photosynthesis (know formula) Photosynthesis (know formula) 6 CO 2 + 6 H 2 O → C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O → C 6 H 12 O 6 + 6 O 2 Carbon dioxide + Water + Light energy → Glucose + Oxygen energy from the sun enters an ecosystem when a plant uses sunlight From Producers to Consumers From Producers to Consumers energy is transferred from producers or autotrophs (animals that make their own food) to consumers or heterotrophs (animals that get their energy from eating others) energy is transferred from producers or autotrophs (animals that make their own food) to consumers or heterotrophs (animals that get their energy from eating others)

3. Nutrient cycling Decomposition connects all trophic levels

4. What Eats What in an Ecosystem

5. Cellular Respiration breaking down food to get energy breaking down food to get energy the opposite of photosynthesis (know formula) the opposite of photosynthesis (know formula) C 6 H 12 O 6 +O 2 ---> CO 2 + H 2 O + ATP sugar + oxygen ----> carbon dioxide + water + energy excess energy is stored as fat or sugar excess energy is stored as fat or sugar

6. Trophic Levels Energy levels Energy levels Energy and heat are lost at each level within the system - some of the energy lost is during cellular respiration Energy and heat are lost at each level within the system - some of the energy lost is during cellular respiration Most of the remaining energy is used by the organism to maintain daily functions such as producing new cells, regulating body temperature, moving etc. Most of the remaining energy is used by the organism to maintain daily functions such as producing new cells, regulating body temperature, moving etc. 10% is passed to the next level 10% is passed to the next level 100% 10% 1% 10% 0.1% 10%

7. Energy Transfer Energy is studied as it travels through food chains, webs and trophic levels Energy is studied as it travels through food chains, webs and trophic levels Food chains = energy flow from 1 organism to the next Food chains = energy flow from 1 organism to the next Food webs = many feeding relationships Food webs = many feeding relationships Each step in the transfer of energy through a food chain or food web is called a trophic level Each step in the transfer of energy through a food chain or food web is called a trophic level Energy pyramids illustrate trophic levels in ecosystems Energy pyramids illustrate trophic levels in ecosystems

8. Energy Pyramids Producers – most energy Herbivores Primary Carnivores Apex Predators

9. Virginia Food Web Create a food web (interconnecting food chains) with at least 10 (ten) of the following Virginia organisms. You must use at least 2 from each column. Color at least your lines!! Producers Corn Grass Strawberries Acorns Dandelions Herbivores Grasshopper Mouse Rabbit Squirrel Ladybug Carnivores Frog Black Snake Fox Red-Tail Hawk Eastern Cougar Omnivores Blue Jay Crow Raccoon Opossum Coyote

10. Example:

11. Blue Jay Blue Jay Opossum Opossum Red Tail Hawk Red Tail Hawk Coyote Coyote

12. Herbivores Herbivores Grasshopper - eats corn, grass, strawberries, dandelions Grasshopper - eats corn, grass, strawberries, dandelions Mouse - eats corn, grass, strawberries, dandelions Mouse - eats corn, grass, strawberries, dandelions Squirrel – eats corn, acorns (may eat strawberries) Squirrel – eats corn, acorns (may eat strawberries) Ladybug - eats corn, grass, strawberries, dandelions Ladybug - eats corn, grass, strawberries, dandelions Rabbit - eats corn, grass, strawberries, dandelions Rabbit - eats corn, grass, strawberries, dandelions Carnivores Carnivores Frog – eats grasshopper, ladybug Frog – eats grasshopper, ladybug Black Snake – eats grasshopper, mouse, squirrel, ladybug, rabbit, blue jay Black Snake – eats grasshopper, mouse, squirrel, ladybug, rabbit, blue jay Fox – eats grasshopper, mouse, squirrel, ladybug, rabbit, raccoon, opossum Fox – eats grasshopper, mouse, squirrel, ladybug, rabbit, raccoon, opossum Red-Tail Hawk - eats grasshopper, mouse, squirrel, ladybug, rabbit, squirrel, blue jay, frog, black snake, Red-Tail Hawk - eats grasshopper, mouse, squirrel, ladybug, rabbit, squirrel, blue jay, frog, black snake, Eastern Cougar –eats grasshopper, mouse, squirrel, ladybug, rabbit, squirrel, frog, black snake, fox, raccoon, opossum, coyote Eastern Cougar –eats grasshopper, mouse, squirrel, ladybug, rabbit, squirrel, frog, black snake, fox, raccoon, opossum, coyote Omnivores Omnivores Blue Jay – eats corn, grass, strawberries, dandelions, grasshopper, ladybug, Blue Jay – eats corn, grass, strawberries, dandelions, grasshopper, ladybug, Crow - eats corn, grass, strawberries, dandelions, grasshopper, ladybug Crow - eats corn, grass, strawberries, dandelions, grasshopper, ladybug Raccoon - eats corn, grass, strawberries, dandelions, grasshopper, mouse, squirrel, ladybug, frog Raccoon - eats corn, grass, strawberries, dandelions, grasshopper, mouse, squirrel, ladybug, frog Opossum - eats corn, grass, strawberries, dandelions, grasshopper, mouse, ladybug, frog Opossum - eats corn, grass, strawberries, dandelions, grasshopper, mouse, ladybug, frog Coyote - eats corn, grass, strawberries, dandelions, grasshopper, mouse, ladybug, frog, rabbit, black snake, fox, raccoon, opossum Coyote - eats corn, grass, strawberries, dandelions, grasshopper, mouse, ladybug, frog, rabbit, black snake, fox, raccoon, opossum

13. Section 2- The Cycling of Materials Carbon Cycle - photosynthesis and respiration / conversion of bones and limestone Carbon Cycle - photosynthesis and respiration / conversion of bones and limestone Affected by humans by burning fossil fuels Affected by humans by burning fossil fuels Nitrogen Cycle – all organisms need nitrogen to survive – nitrogen must first be altered by nitrogen fixing bacteria in soil Nitrogen Cycle – all organisms need nitrogen to survive – nitrogen must first be altered by nitrogen fixing bacteria in soil Phosphorus Cycle – needed to form bones and teeth – very slow process – enters through decomposition, erosion, run-off of fertilizers, etc Phosphorus Cycle – needed to form bones and teeth – very slow process – enters through decomposition, erosion, run-off of fertilizers, etc

14. Carbon cycle CO 2 in atmosphere Diffusion Respiration Photosynthesis Plants and algae Plants Animals Industry and home Combustion of fuels Animals Carbonates in sediment Bicarbonates Deposition of dead material Deposition of dead material Fossil fuels (oil, gas, coal) Dissolved CO2

17. Birds Herbivores Plants Amino acids Carnivores Atmospheric nitrogen Loss to deep sediments Fish Plankton with nitrogen- fixing bacteria Nitrogen- fixing bacteria (plant roots) Nitrogen- fixing bacteria (soil) Denitrifying bacteria Death, excretion, feces Nitrifying bacteria Soil nitrates Excretion Decomposing bacteria Ammonifying bacteria Nitrogen cycle

18. Loss to deep sediment Rocks and minerals Soluble soil phosphate Plants and algae Plants Urine Land animals Precipitates Aquatic animals Animal tissue and feces Animal tissue and feces Decomposers (bacteria and fungi) Decomposers (bacteria and fungi) Phosphates in solution Loss in drainage Phosphorus cycle

19. Fertilizers and the Nitrogen and Phosphorus Cycles Fertilizers and the Nitrogen and Phosphorus Cycles excess amounts of fertilizers can enter ecosystems through runoff and cause algal blooms excess amounts of fertilizers can enter ecosystems through runoff and cause algal blooms algal blooms can deplete the water of important nutrients that fish and other organisms need to survive, such as oxygen algal blooms can deplete the water of important nutrients that fish and other organisms need to survive, such as oxygen Acid Precipitation Acid Precipitation Burning wood, coal, or oil adds nitric oxide to the atmosphere which combines with water to form nitric acid Burning wood, coal, or oil adds nitric oxide to the atmosphere which combines with water to form nitric acid This forms acid rain and snow This forms acid rain and snow Section 2- The Cycling of Materials

22. Water is constantly being cycled between the atmosphere, the ocean and land. Water is constantly being cycled between the atmosphere, the ocean and land. This cycling is a very important process that helps sustain life on Earth. This cycling is a very important process that helps sustain life on Earth. As the water evaporates, vapors rise and condense into clouds. As the water evaporates, vapors rise and condense into clouds. The clouds move over the land, and precipitation falls in the form of rain, ice or snow. The clouds move over the land, and precipitation falls in the form of rain, ice or snow. The water fills streams and rivers, and eventually flows back into the oceans where evaporation starts the process anew. The water fills streams and rivers, and eventually flows back into the oceans where evaporation starts the process anew.

23. Section 3 - How Ecosystems Change  The sequence of community changes after a disturbance  transition in species composition over ecological time  years or decades Mt. St. Helens

24. Primary Succession Primary Succession New land is formed New land is formed River deltas, sand dunes, lava flows River deltas, sand dunes, lava flows Little or no established soil Little or no established soil Pioneer species = lichens (symbiotic relationship between fungi and algae), mosses, etc Pioneer species = lichens (symbiotic relationship between fungi and algae), mosses, etc Secondary Succession Secondary Succession Areas where disturbance has occurred Areas where disturbance has occurred Fire, hurricane, clearcutting, etc. Fire, hurricane, clearcutting, etc. Established soil is present – much quicker than primary Established soil is present – much quicker than primary Types of Succession

25. Succession From bare soil, then… From bare soil, then… bacteria bacteria lichens & mosses lichens & mosses grasses grasses shrubs shrubs trees trees make soil { Change in species mix over time

26. Disturbances Most communities are in a state of change due to disturbances Most communities are in a state of change due to disturbances fire, weather, human activities, etc. fire, weather, human activities, etc. not all are negative not all are negative

27. Climax forest  solar energy levels  temperature  rainfall  fertility & depth of soil The species mix of climax forest is dependent on the abiotic factors of the region birch, beech, maple, hemlock

29. Old field succession occurs when farmland is abandoned - weeds and grasses soon cover it - within 10 years shrubs cover the land and within 20 years, a young pine forest exists - it will take about 100 years for the land to return to the climax community that existed before the farm Old field succession occurs when farmland is abandoned - weeds and grasses soon cover it - within 10 years shrubs cover the land and within 20 years, a young pine forest exists - it will take about 100 years for the land to return to the climax community that existed before the farm Section 3 - How Ecosystems Change