The Importance of Insects in Ecosystems

1. Chapter 3 Ecosystems: What Are They and How Do They Work?

2. Core Case Study: Have You Thanked the Insects Today? • Many plant species depend on insects for pollination and plant reproduction. • Insects can control other pest insects by eating them. • They also mix up the soil Figure 3-1

3. Welcome back!TPK Ecosystems • Please describe one biome you visited on the break, and explain how being in this biome made you feel  • In the biome mentioned above, were there different ecosystems? Explain… • In your own words, what do you think an ecosystem is? • The core case study for ch 3 is on “thanking our insects” what do insects have to do with ecosystems?

4. Possible answers to TPK(by Ms May) • I visited a few different biomes during the break. I will focus on one for this discussion. I went to the Colorado desert, specifically Anza Borrego. (I will explain the rest verbally) • In this biome yes! There were different ecosystems. We actually hiked to a palm oasis next to a stream that was FLOWING with water, we call this a “riparian ecosystem” (stream side).

5. continued 2. There were cat-tails and bulrushes, as well as water insects, with the common visitor being herds of big horn sheep. There were also very dry areas with Ocotillo Cactus, and desert reptiles 3. The word ecosystem describes the variety of biological communities (such as a forest or a pond) in an area and how those communities interact with each other and with the nonliving (abiotic) components of the area 4. Insects are the underappreciated workers in our ecosystems, they have vital roles in pollination, nutrient cycling, bug control, beauty (butterflies) without insects our ecosystems would collapse

9. Core Case Study: Have You Thanked the Insects Today? • …if all insects disappeared, humanity probably could not last more than a few months [E.O. Wilson, Biodiversity expert]. • Insect’s role in nature is part of the larger biological community in which they live. why are honeybees dis.flv honeybees part 2.flv

10. THE NATURE OF ECOLOGY • Ecology is • How organisms interact with one another and with their nonliving environment. Figure 3-2

11. So, really intricate and amazing interrelationships occur between plants and animals.

12. Well, as mentioned earlier, plants rely on insects, birds, and rodents for pollination Fynbos biome

13. And, of course birds and animals need plants……what what

14. Biosphere!!!!!!!

16. Re-wind: from this diagram I would like you to remember the differences between good and bad ozone, and the greenhouse vs. the ozone layer

17. What Happens to Solar Energy Reaching the Earth? Solar energy • Warms and lights up the troposphere • Drives the cycling of matter • Evaporates water and drives weather and climate • 1% generates winds • Green plants/algae use less than .1% in photosynthesis Figure 3-8

18. What are the abiotic factors in this diagram? Sun Oxygen (O2) Producer Carbon dioxide (CO2) Secondary consumer (fox) Primary consumer (rabbit) Precipitation Producers Falling leaves and twigs Soil decomposers Soluble mineral nutrients Water Fig. 3-10, p. 57

19. Factors That Limit Population Growth • Availability of matter and energy resources can limit the number of organisms in a population. • Examples of limiting factors: (temperature, sunlight, nutrients, dissolved oxygen, salinity…etc) Figure 3-11

20. Lower limit of tolerance Upper limit of tolerance No organisms Few organisms Few organisms No organisms Abundance of organisms Population size Zone of intolerance Zone of intolerance Zone of physiological stress Zone of physiological stress Optimum range Low Temperature High Fig. 3-11, p. 58

21. Write the chemical equations for photosynthesis and respiration. Explain how these two processes are intertwined; include the terms oxygen, carbon dioxide, light reaction, dark reaction, chloroplasts, mitochondria, photosynthesis, respiration, glucose, water, sunlight, ATP, plants, animals. Good luck!!

22. Producers: Basic Source of All Food • Most producers capture sunlight to produce carbohydrates by photosynthesis: • KNOW THE FORMULA

23. Energy Flow in an Ecosystem: Losing Energy in Food Chains and Webs • In accordance with the 2nd law of thermodynamics, there is a decrease in the amount of energy available to each succeeding organism in a food chain or web.

24. Energy Flow in an Ecosystem: Losing Energy in Food Chains and Webs • Ecological efficiency: percentage of useable energy transferred as biomass from one trophic level to the next.(2-40% range) Figure 3-19

25. Productivity of Producers: The Rate Is Crucial • Gross primary production (GPP) • Rate at which an ecosystem’s producers convert solar energy into chemical energy as biomass. Figure 3-20

26. Gross primary productivity (grams of carbon per square meter) Fig. 3-20, p. 66

27. Net Primary Production (NPP) • NPP = GPP – R • Rate at which producers use photosynthesis to store energy minus the rate at which they use some of this energy through respiration (R). Figure 3-21

28. Sun Photosynthesis Energy lost and unavailable to consumers Respiration Gross primary production Net primary production (energy available to consumers) Growth and reproduction Fig. 3-21, p. 66

29. What are nature’s three most productive and three least productive systems? Figure 3-22

30. Chemosynthesis: • Some organisms such as deep ocean bacteria draw energy from hydrothermal vents and produce carbohydrates from hydrogen sulfide (H2S) gas .

31. Consumers: Eating and Recycling to Survive • Consumers (heterotrophs) get their food by eating or breaking down all or parts of other organisms or their remains. • Herbivores • Primary consumers that eat producers • Carnivores • Secondary consumers eat primary consumers • Third and higher level consumers: carnivores that eat carnivores. • Omnivores • Feed on both plant and animals.

32. Decomposers and Detrivores Burying Beetles Video -- National Geographic • Decomposers: Recycle nutrients in ecosystems. • Detrivores: Insects or other scavengers that feed on wastes or dead bodies. Generally scavengers are considered to be larger animals and detrivores are insects. Figure 3-13

33. Detrivores Decomposers Termite and carpenter ant work Carpenter ant galleries Bark beetle engraving Long-horned beetle holes Dry rot fungus Wood reduced to powder Mushroom Time progression Powder broken down by decomposers into plant nutrients in soil Fig. 3-13, p. 61

34. Aerobic and Anaerobic Respiration: Getting Energy for Survival • Organisms break down carbohydrates and other organic compounds in their cells to obtain the energy they need. • This is usually done through aerobic respiration. • The opposite of photosynthesis

35. Aerobic and Anaerobic Respiration: Getting Energy for Survival • Anaerobic respiration or fermentation: • Some decomposers get energy by breaking down glucose (or other organic compounds) in the absence of oxygen. • The end products vary based on the chemical reaction: • Methane gas • Ethyl alcohol • Acetic acid • Hydrogen sulfide

36. Two Secrets of Survival: Energy Flow and Matter Recycle • An ecosystem survives by a combination of energy flow and matter recycling. Figure 3-14

37. Biodiversity Loss and Species Extinction: Remember HIPPO • H for habitat destruction and degradation • I for invasive species • P for pollution • P for human population growth • O for overexploitation

39. Why???????

40. But what’s wrong with corn?” you might ask. In a sense, nothing. In its whole form, corn is a cheap, filling source of starch and vitamins, and its obvious versatility makes it an important culinary staple. As it has been, for thousands of years. But only the tiniest fraction of our corn supply ends up boiled and buttered, or even converted to cornmeal. Given current farm bills and modern commodity agriculture, large-scale corn producers receive government subsidies—to the tune of 4 billion dollars a year—making the crop ludicrously (and, in a sense, artificially) cheap. That creates the incentive to sell, sell, sell, in every possible form. And since we can only eat so much corn on the cob, that means conjuring all sorts of corn-based derivatives. So we end up with corn processed beyond recognition, into forms that eliminate virtually all of its nutritional content.

41. Of course then we also have URBAN DEVELOPMENT

42. Why Should We Care About Biodiversity? The health of a species reflects the health of an ecosystem which reflects of the health of the biosphere which is where humans live. “We are all connected”

43. Some species are so critical to the functioning of an Ecosystem that they are called KEYSTONE SPECIES 1800’s sea otters hunted for fur Sea otters eat sea urchins, so with no predators, they began to multiply Fish begin to decline because Kelp are the breeding grounds for fish, this affected fishermen's catches. Sea urchins eat kelp, which then began to disappear California Sea Otter Tax Check-Off - Defenders of Wildlife

47. Food Webs • Trophic levels are interconnected within a more complicated food web. Figure 3-18

48. Animation: Prairie Food Web PLAY ANIMATION

49. Which of the following ecosystems has the highest average net primary productivity? a. agricultural land b. open ocean c. temperate forest d. swamps and marshes e. lakes and streams Which of the following ecosystems has the lowest level of kilocalories per square meter per year? a. open ocean b. tropical rain forest c. agricultural land d. lakes and streams e. temperate forest

50. Ecosystem egg • 1. What does the light reaction in photosynthesis produce? • 2. Which law of thermodynamics accounts for the 10% rule? • 3. Which terrestrial ecosystem has the highest GPP? • 4. which aquatic ecosystem has the highest GPP?