Environmental Science: Toward A Sustainable Future Chapter 3

1. Environmental Science: Toward A Sustainable Future Chapter 3 Ecosystems: How They Work Version 1.0 Term 2051

3. The chapter deals with the transfer of Energy and Nutrients by Ecosystems. Capture of sun energy and transfer through different trophic levels. Capture of essential elements of life and transfer through different trophic levels. Nutrient cycles. Human impacts on ecosystem function.

4. First Principle of Ecosystem Sustainability Ecosystems use sunlight as their source of energy.

5. Human Violations of the First Principle of Ecosystem Sustainability Very little direct use of solar energy. Excessive use of fossil fuels. Feeding largely on the third trophic level. Use of coal or nuclear power. Pollution and hazardous waste problems Use of agricultural land to produce meats. Not efficient energy transfer

6. There are Elements 92 Natural Elements

8. The periodic table of the elements.

9. (A) Periods (rows) of the periodic table, and (B) families (columns) of the periodic table.

10. Elements of LifeYou are a carbon based life form.

11. Production of Carbon Based Compounds needed for Life

12. Four Spheres of Earth�s Environment

13. Solids, Liquids, and GasesSince the biosphere is contains these 3 states of matter it is necessary to understand what they are. Gases have no defined shape or defined volume Low density Liquids flow and can be poured from one container to another Indefinite shape and takes on the shape of the container. Solids have a definite volume Have a definite shape.

14. (A) A gas dispenses throughout a container, taking the shape and volume of the container. (B) A liquid takes the shape of the container but retains its own volume. (C) A solid retains its own shape and volume.

15. Three states of Water (matter)

16. Elements Combine chemically or physically Chemical combinations produce new substance and the original components cannot be retrieved. Burning wood produces ashes and wood cannot be made from ashes. Physical combinations allow the original component to be recovered. For example, salt will dissolve in water and cannot be seen. But if the water is allowed to evaporate the salt will be left behind.

17. Rocks & Minerals Atom is a fundamental unit of all elements Elements are chemically combined to form minerals. Minerals are made of two or more atoms Minerals are physically combined to form rocks. Rocks are made of two or more minerals. Soil is generally made of different minerals.

18. Minerals Any hard, crystalline, inorganic material of a given chemical composition. Each mineral is made up of dense clusters of two or more atoms (elements) bonded together by an attraction between positive and negative charges. Examples : diamonds, quartz, silicon, etc. Most rocks are made up of relatively small crystals of two or more minerals. As an example, lava is made up of elements that have been melted together.

20. Minerals � hard crystalline compoundsComposed of two or more elements

21. A crystal is composed of a structural unit such as a cube, that is repeated in three dimensions. This is the basic structural unit of a crystal of sodium chloride or salt.

22. The Atmosphere in General Composition of the Atmosphere Nitrogen (N2) is the most abundant gas in the Earth�s atmosphere making up about 78 %. Oxygen is the second most abundant making up about 21 %. Nitrogen in the atmosphere moves through the Nitrogen Cycle where it is removed from the atmosphere by bacteria and lightening These nitrogen compounds are then taken up by plants and utilized in growth and development.

23. Composition of the Atmosphere continued Oxygen (O2) also cycles in the atmosphere Living organisms are used as food sources and oxygen is utilized in most organisms that digest other organisms. Chemical weathering of rocks can cause oxides to form, locking up the oxygen within minerals. Oxygen is released into the atmosphere by plants through the photosynthesis process. Argon only makes up about 1% of the atmosphere and does not react with anything.

24. Composition of the Atmosphere continued Carbon Dioxide (CO2)makes up approximately 0.03 % of the Earth�s atmospheric gases. Carbon dioxide concentrations in the atmosphere is regulated by: Removal of CO2 from the atmosphere as green plants fix the CO2 into carbohydrates *** very important for living organisms *** Exchanges of CO2 between the atmosphere and the oceans Chemical reactions between the atmosphere and limestone Water Vapor in the atmosphere varies considerably and also cycles in the Hydrologic Cycle. This is the cycle of evaporation and precipitation that results almost daily.

25. Earth's atmosphere has a unique composition of gases when compared to that of the other planets in the solar system.

26. Those Atmospheric Gases  Required by living organisms

27. Three main life dependent gases in air.Nitrogen, Oxygen and Carbon Dioxide

28. Interrelationship � Air, Water & Minerals

29. Organic Molecules � Make up living organismsThe diagram show bonding of various elements.

30. Atom BondingRecall that Atoms are the smallest part of a element that retains the properties of that element. Atoms can combine by sharing atoms to reach a stable state. The diagram representation is O = O. The = means that 2 electron pairs are shared between the 2 Oxygen atoms. ( Do not read this symbol as equal.)

31. Matter Matter: anything that occupies space and has mass. Cannot be created or destroyed. Can be changed from one form into another. Can be recycled. Considered as the amount of substance that comprises an object. Is a measure of inertia. Atom is the smallest particle of a substance that retains the properties of the substance. The basic unit of matter.

32. Biosphere Biomes Species Organism Organs * Cell types > Molecules - Elements (atoms) Life as a hierarchy of organization of matter

33. Life as a hierarchy of organization of matter. 8. Biosphere7. Biomes6. Population of species5. Organism4. Organs3. Cell Types2. Molecules (DNA)1. Atoms

34. Energy Energy: anything that has the ability to move matter, has no mass and does not occupy space. Cannot be created or destroyed. Cannot be recycled. Can be changed from one form to another. Can be measured. Has the ability to do work.

35. Laws of Thermodynamics (Heat)

36. Potential Energy has the potential to do work.

37. Examples of Energy Conversion

38. Storage and Release of Potential Energy

39. Entropy � How is yours? Systems will go spontaneously in one direction only. Which is toward increasing entropy..

40. EntropyLearn this Word and Impress Others. Entropy refers to the degree of disorder in a system. Increasing Entropy means to increase disorder. Everything goes in one direction. More => Less The direction is that of increasing Entropy Heat energy flows from more energy to less. In a glass of water with ice, heat energy flows from the liquid into the ice causing the ice to melt. You probably thought the ice added cold to the liquid. The ice took heat energy from the liquid.

41. Energy Flow � To increase Entropy and increase disorder

42. Example of the Laws of Conservation of Matter and Thermodynamics

43. PhotosynthesisEnergy Conversion

44. Producers as chemical factoriesUsing Solar Energy to make Glucose from C02 and H20

45. Cell RespirationEnergy Releasing

46. Only a small portion of the food ingested by a consumer is assimilated by into the body.

47. Energy Productivity of Different Ecosystems

48. Energy distribution at a Trophic Level Some energy goes into energy Blood pumping, running, etc. Some energy is converted to growth Hair, nails, height, etc. Storage of energy as glucose. Some energy is given off as waste and not consumed.

50. The Second Principle of Ecosystem Sustainability Ecosystems dispose of wastes and replenish nutrients by RECYCLING all elements.

51. Violations of the Second Principle of Ecosystem Sustainability by Human Systems Lack of recycling. 1 Billion plastic water bottles go into a landfills each year. Excessive use of fertilizers. Destruction of tropical rain forests. Nutrient overcharge into aquatic ecosystems. Production and use of non-biodegradable compounds.

52. The Carbon Cycle Carbon atoms from CO2 in the atmosphere become carbon atoms of organic molecules in the plants. Carbon atoms then move into the food web and become part of the tissue of other organisms and move up thru the food chains. Eventually decomposers convert the organic matter back in to the original nutrients. No matter where CO2 released it will eventually return to the atmosphere.

53. The Carbon Cycle � A Gas

54. The Phosphorus CycleRepresentative of all mineral nutrients. Phosphorus exists in various rocks and minerals as an inorganic phosphate ion. No gas phase. Plant absorb phosphates from soil or a water solution. Phosphate is bonded to organic compounds by the plant. Phosphate is transferred from producers to the rest of the ecosystem. Phosphate is released via waste products and recycling occurs.

55. The Phosphorus Cycle - Minerals

56. The Nitrogen Cycle � A Gas Has aspects of the carbon and phosphorous cycles. Yet, it is unique in that many steps of the cycle are performed by bacteria in soils, water, and sediments. Nitrogen gas needs to be converted to ammonia via a process called nitrogen fixation in order to be used by plants. Plants incorporate nitrogen into organic compounds like proteins and nucleic acids. Nitrogen then follows the energy flow pattern from herbivores to carnivores and finally, decomposers.

57. Nitrogen Fixation � From a gas to a mineral

58. The Nitrogen Cycle � Atmospheric Gas

59. Nutrient recycling and energy flow in an Ecosystem

61. Nutrient flow in Human Society

62. The End Chapter 3

63. Can you match the Elements on the left with the Molecules on the right. Nitrogen Carbon Hydrogen Oxygen Phosphorus Sulfur Glucose Proteins Starch Fats Nucleic acids All of the above

64. Match Outcomes (Left) With Process (Right) Releases O2 Stores energy Releases CO2 Uses CO2 Releases energy Produces sugar Uses sugar Uses O2 Photosynthesis Cell respiration Both Neither

65. Match Outcomes (Left) With Organisms (Right) Releases O2 Stores energy Releases CO2 Uses CO2 Releases energy Produces sugar Uses sugar Uses O2 Plants Animals Both Neither