Chap 36 Ecosystems and Conservation Biology

1. Chap 36 Ecosystems and Conservation Biology

2. 36.1 Feeding Relationships • Every organism requires energy to carry out life processes such as growing, moving, and reproducing. • Producers: • Convert light energy from sunlight to chemical energy • Consumers: • Obtain chemical energy from consuming other organisms • Decomposers: • Break down wastes and dead organisms

3. How is energy passed between these organisms?

4. Flower takes in sunlight • Grasshopper eats flower • Mouse eats grasshopper • Eagle eats mouse

5. What is this an example of? • Food chain: • Pathway of food transfer from one trophic level to another. • Trophic level: • Feeding level

6. Producers • Always on the bottom of the food chain • Base for all food webs • If we had no producers, would anything live? • No! Ex.

7. Consumers • Herbivore: • Only eats plants • Carnivore: • Only eats other organisms • Omnivore: • Eats both plants and other consumers

8. Consumers • Primary consumers (1st level consumer)(2nd trophic level) • Feeds directly on the producers • Secondary consumers (2nd level consumer)(3rd trophic level) • Consumer that eats primary consumers • Tertiary consumers (3rd level consumer)(4th trophic level) • Consumer that eats secondary consumers

10. What can primary consumers only be? • Herbivores • Omnivores • Carnivores

11. Decomposers • At each trophic level, organisms produce waste and die. • The waste and remains of dead organisms is called detritus. • Often called scavengers. • Ex. • Earthworms, crayfish, vultures etc.

12. What is this?

13. Food Web • Food web: • Pattern of feeding represented by interconnected and branching food chains.

14. 36.2 Energy Flows • Of the light energy that reaches plants what percentage is used for photosynthesis? • 1% • Biomass: • Organic material manufactured by plants • Primary productivity: • The rate of which producers in an ecosystem build biomass. • Primary productivity determines the maximum amount of energy available to all higher trophic levels.

15. Which biome has the most primary productivity? • Desert • Savanna • Deciduous forest • Rain forest

16. Rain forest

17. Ecological Pyramids • As each consumer feeds, some energy is transferred from lower trophic levels to higher, but most energy in the preys organism’s biomass is lost.

18. Caterpillar eats a leaf • 50% of the energy in the leaf passes as the caterpillars waste. • The caterpillar uses 35% of the energy from the leaf for energy for itself. • Only about 15% of the leafs stored energy is turned into biomass for the caterpillar.

19. Energy Pyramid • Energy pyramid:Shows the energy loss from one trophic level to another. • An average of 10% of energy is converted to biomass in the next trophic level. • 90% is lost as heat.

20. Energy Pyramid

21. Pyramid of numbers • Pyramid of numbers: • Shows the number of individual organisms in each trophic level. • Organized like energy pyramids.

22. 36.3 Chemical Cycles • General steps • 1. Producers incorporate chemicals from the nonliving environment into organic compounds. • 2. Consumers feed on producers, either using them as energy or releasing them as waste. • 3. Organisms die and decomposers break them down and return to soil.

23. Carbon and Oxygen Cycle • 1. Volcanoes, organisms, and cellular respiration produces carbon dioxide. • 2. Plants uses the carbon dioxide and produce oxygen.

24. Nitrogen Cycle • 1. Bacteria convert nitrogen gas to ammonia through a process called nitrogen fixation. • 2. Other bacteria take the ammonia and produce ammonium though a process called nitrification. • 3. Plants absorb the ammonium and can be consumed by other organisms. • Organisms die and cycle repeats.

26. Water Cycle • Plants transpire, and water evaporates from bodies of water. • Condensation releases by precipitation back to the Earth. • Run off and groundwater go into bodies of water.

28. 36.4 Human Activities • Human activities can affect chemical cycling by moving nutrients from one place to another. • Humans eat vegetables from different parts of the country. • Human waste might be carried to the ocean in sewage.

29. Carbon Cycle Impacts • Burning of wood and fossil fuels is one source of carbon dioxide. • As nations industrialize and use wood, carbon levels increase. • What organisms use carbon dioxide to make oxygen? • Plants

30. What is happening to trees and forests? • Deforestation: • Clearing of forests for agriculture.

31. All the carbon dioxide builds up in the Earth’s atmosphere, trapping heat. • Greenhouse effect: • Natural process that stops all sun’s heat from escaping rapidly back to space.

32. This is leading to global warming. • Global warming: • Rise in Earth’s average temperature.

33. Other effects of Pollution • Who here eats fish? • Why do some people not eat fish anymore? • High amounts of mercury.

34. Bio Magnification • If a small fish has mercury in its system and gets eaten by a bigger fish… the bigger fish now has a higher amount of mercury in its system. • The amount of mercury increases as the small fish gets consumed and moves up a food chain.

36. Ozone Layer • Pollution in the atmosphere affects a gas called ozone (O3). • Ozone layer absorbs ultraviolet radiation, and shields organisms. • Ozone layer is thinning because of chlorofluorocarbons. • Aerosol cans, refrigerator units.

37. 36.5 Conservation Biology • Which biome has the most biodiversity? • Tropical Rainforest!

38. What is happening to our tropical rainforests? • Deforestation

39. Threats to Biodiversity • 11% of the 9,040 bird species are endangered. • 680 plant species of the 20,000 plant species in the US are endangered. • Biologist estimate that 20% of the freshwater fish in the world have either become extinct or threatened.

40. Habitat Destruction • The human population is increasing so we need more land for agriculture, roads etc.

41. Introduced Species • Introduced species: Non-native species • House sparrows, starlings came over from Europe. • Compete with native birds for nesting spots. • Share resources.

42. Overexploitation • Overexploitation: • Practice of harvesting or hunting to a degree that the number of remaining individuals may not be able to sustain the population. • Ex. Rhino-Use horns for trade and medicine. • Scallop- Overfished for food.

43. Conversation Biology • How to we maintain biodiversity and ecosystems? • Balance demands for resources • Establish areas than humans can not interfere with. (buffer zones) • Develop natural resources.