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  • 1. Biotic and Abiotic Factors Biotic Abiotic 1. Food – both quantity and quality of food are important. 2. Predators – refer back to predator prey relationships. 3. Competitors – other organisms may require the same resources from an environment. 4. Parasites – may cause disease and slow down the growth of an organism. 1. Temperature – higher temperatures speed up enzyme-catalyzed reactions and increase growth. 2. Oxygen Availability – affect the rate of energy production by respiration. 3. Light Availability – for photosynthesis and breeding cycles in animals and plants. 4. Toxins and pollutants – tissue growth may be reduced. 5/1/2013 Author-Guru Ecosystem IB /ESS 1
  • 2. 2.2 Measuring Abiotic Components of the System 2.3 Measuring Biotic Components of the System 5/1/2013 Author-Guru Ecosystem IB /ESS 2
  • 3. Setting up stage quadrats of 100m2 in the meadow area of the ecological gradient 5/1/2013 Author-Guru Ecosystem IB /ESS 3
  • 4. Setting up group quadrats of 1m2 5/1/2013 Author-Guru Ecosystem IB /ESS 4
  • 5. Setting up sampling quadrats of 0.1m2 in the meadow 5/1/2013 Author-Guru Ecosystem IB /ESS 5
  • 6. Using the light meter in the forest group quadrat of 1m2 5/1/2013 Author-Guru Ecosystem IB /ESS 6
  • 7. Soil Temperature 5/1/2013 Author-Guru Ecosystem IB /ESS 7
  • 8. Taking a soil sample with a soil borer (auger) in the forest section of the gradient 5/1/2013 Author-Guru Ecosystem IB /ESS 8
  • 9. Results of soil borer sample, Chemical analysis of the soil can be seen in the background 5/1/2013 Author-Guru Ecosystem IB /ESS 9
  • 10. Testing the meadow area for pH, phosphates, nitrates and potassium 5/1/2013 Author-Guru Ecosystem IB /ESS 10
  • 11. Collecting samples in Ziploc bags for analysis back in the lab 5/1/2013 Author-Guru Ecosystem IB /ESS 11
  • 12. Taking observations in the forest Notice the absence of plant growth on the forest floor 5/1/2013 Author-Guru Ecosystem IB /ESS 12
  • 13. Chemical testing in the forest 5/1/2013 Author-Guru Ecosystem IB /ESS 13
  • 14. Insect sampling with net in the meadow 5/1/2013 Author-Guru Ecosystem IB /ESS 14
  • 15. Setting up 0.1m2 sampling quadrats for biomass analysis 5/1/2013 Author-Guru Ecosystem IB /ESS 15
  • 16. Next Chapter….. 5/1/2013 Author-Guru Ecosystem IB /ESS 16
  • 17. Chapter : 2.5.2 Topic : Photosynthesis & Respiration in Energy Transformation 5/1/2013 Author-Guru Ecosystem IB /ESS 17
  • 18. Figure 10.1 Photoautotrophs 5/1/2013 Author-Guru Ecosystem IB /ESS 18
  • 19. Photosynthesis in Plants • Chloroplasts are the location of photosynthesis in plants • Green color from chlorophyll (photosynthetic pigment) • Found in cells of mesophyll – interior tissue of leaves • Gases exchanges through the stomata • Water enters through xylem of roots 5/1/2013 Author-Guru Ecosystem IB /ESS 19
  • 20. Figure 10.2 Focusing in on the location of photosynthesis in a plant 5/1/2013 Author-Guru Ecosystem IB /ESS 20
  • 21. 5/1/2013 Author-Guru Ecosystem IB /ESS 21
  • 22. Energy Processes • Photosynthesis (Green Plants) sunlight +water + carbon dioxide  oxygen + sugars • Respiration (All living things) oxygen + sugars  ATP +water + carbon dioxide • ATP is molecular energy storage 5/1/2013 Author-Guru Ecosystem IB /ESS 22
  • 23. Producers • Make their own food - photoautotrophs, chemoautotrophs • Convert inorganic materials into organic compounds • Transform energy into a form usable by living organisms 5/1/2013 Author-Guru Ecosystem IB /ESS 23
  • 24. 5/1/2013 Author-Guru Ecosystem IB /ESS 24
  • 25. Photosynthesis • Inputs – sunlight, carbon dioxide, water • Outputs – sugars, oxygen • Transformations – radiant energy into chemical energy, inorganic carbon into organic carbon 5/1/2013 Author-Guru Ecosystem IB /ESS 25
  • 26. Respiration • Inputs - sugars, oxygen • Outputs - ATP, carbon dioxide, water • Transformations – chemical energy in carbon compounds into chemical energy as ATP, organic carbon compounds into inorganic carbon compounds 5/1/2013 Author-Guru Ecosystem IB /ESS 26
  • 27. • The fundamental energy source for most of the environment is the sun. • Photoautotrophs capture the sun’s energy and use it to make organic compounds through photosynthesis. • Photoautotrophs are often also called primary producers because they establish the basis for most other production; they create organic material from inorganic, or non-living, sources. • The process of photosynthesis transforms carbon dioxide and water into simple carbohydrates. 5/1/2013 Author-Guru Ecosystem IB /ESS 27
  • 28. 5/1/2013 Author-Guru Ecosystem IB /ESS 28
  • 29. What is Photosynthesis? • Conversion by plants of light energy into chemical energy, which is then used to support the plants' biological processes. • Process by which cells containing chlorophyll in green plants convert incident light to chemical energy and synthesize organic compounds from inorganic compounds, especially carbohydrates from carbon dioxide and water, accompanied by the simultaneous release of oxygen 5/1/2013 Author-Guru Ecosystem IB /ESS 29
  • 30. • carbon dioxide + water chlorophyll →→→→→→→→ light energy sugar (glucose) + oxygen 5/1/2013 Author-Guru Ecosystem IB /ESS 30
  • 31. 5/1/2013 Author-Guru Ecosystem IB /ESS 31
  • 32. 5/1/2013 Author-Guru Ecosystem IB /ESS 32
  • 33. 5/1/2013 Author-Guru Ecosystem IB /ESS 33
  • 34. What is Respiration ? • The process by which oxygen is taken in and used by tissues in the body and carbon dioxide is released. • The energy producing process of breathing, by which an organism supplies its cells with oxygen and relieves itself of carbon dioxide. 5/1/2013 Author-Guru Ecosystem IB /ESS 34
  • 35. 5/1/2013 Author-Guru Ecosystem IB /ESS 35
  • 36. RECAP • What is photosynthesis? • What is RESPIRATION? • Output of Photosynthesis • Output of Respiration 5/1/2013 Author-Guru Ecosystem IB /ESS 36
  • 37. 2.5.5-- Define the terms gross productivity, net productivity, primary productivity and secondary productivity. 5/1/2013 Author-Guru Ecosystem IB /ESS 37
  • 38. 2.5.5-.7 Productivity 5/1/2013 Author-Guru Ecosystem IB /ESS 38
  • 39. • • • • • • • • Gross productivity (GP) Gross Primary Productivity (GPP) Gross Secondary Productivity (GSP) Net productivity Net Primary Productivity (NPP) Net Secondary Productivity (NSP) Primary productivity Secondary productivity 5/1/2013 Author-Guru Ecosystem IB /ESS 39
  • 40. What is Productivity? • The rate at which producers convert light energy into chemical energy is called primary productivity. 5/1/2013 Author-Guru Ecosystem IB /ESS 40
  • 41. • PRODUCTIVITY is production per unit time. Energy per unit area per unit time (J m-2 yr-1) Or Biomass added per unit area per unit time (g m-2 yr-1) 5/1/2013 Author-Guru Ecosystem IB /ESS 41
  • 42. Primary Production The energy entering ecosystems is fixed by producers in photosynthesis. Gross primary production (GPP) is the total energy fixed by a plant through photosynthesis. Grassland: high productivity Net primary production (NPP) is theGPP minus the energy required by the plant for respiration. It represents the amount of stored chemical energy that will be available to consumers in an ecosystem. Grass biomass available to consumers 5/1/2013 Author-Guru Ecosystem IB /ESS 42
  • 43. Primary Productivity The term used to describe the amount of organic matter an ecosystem produces from solar energy within a given area during a given period of time. Primary productivity simply defined is the production of new plant material. In the oceans this new plant material is phytoplankton 5/1/2013 Author-Guru Ecosystem IB /ESS 43
  • 44. Measuring Plant Productivity The primary productivity of an ecosystem depends on a number of interrelated factors, such as light intensity, temperature, nutrient availability, water, and mineral supply. The most productive ecosystems are systems with high temperatures, plenty of water, and non-limiting supplies of soil nitrogen. 5/1/2013 Author-Guru Ecosystem IB /ESS 44
  • 45. Ecosystem Productivity The primary productivity of oceans is lower than that of terrestrial ecosystems because the water reflects (or absorbs) much of the light energy before it reaches and is utilized by the plant. kcal m-2y-1 Although the open ocean’s kJ m-2y-1 productivity is low, the ocean contributes a lot to the Earth’s total production because of its large size. Tropical rainforest also contributes a lot because of its high productivity. 5/1/2013 Author-Guru Ecosystem IB /ESS 45
  • 46. Gross Productivity Gross productivity is the total gain energy per unit time in plants. It is the biomass that could be gained by an organism before any deduction. But all organism have to respire to stay alive so some of this energy is used up in staying alive instead of being used to grow Photosynthesis 2.2% Reflection 3.0 Evaporation (including transpiration and heating of the surroundings 94.8 Total 5/1/2013 100.0% Author-Guru Ecosystem IB /ESS 46
  • 47. 5/1/2013 Author-Guru Ecosystem IB /ESS 47
  • 48. 5/1/2013 Author-Guru Ecosystem IB /ESS 48
  • 49. What is Gross Productivity? • Gross Productivity (GP) – is the total gain in energy or biomass per unit time. • This is sometimes shown as GPP – Gross Primary Productivity • It is related to the total amount of chemical energy incorporated into the producers. • The producers use some of this energy during respiration and energy needs which is eventually lost to the environment as heat. • The remaining energy is available to the herbivores and is known as net primary productivity (NPP) 5/1/2013 Author-Guru Ecosystem IB /ESS 49
  • 50. Gross Productivity • Varies across the surface of the earth • Generally greatest productivity – In shallow waters near continents – Along coral reefs – abundant light, heat, nutrients – Where upwelling currents bring nitrogen & phosphorous to the surface • Generally lowest – In deserts & arid regions with lack of water but high temperatures – Open ocean lacking nutrients and sun only near the surface 5/1/2013 Author-Guru Ecosystem IB /ESS 50
  • 51. GROSS PRIMARY PRODUCTIVITY (GPP) • GPP is the quantity of matter produced, or solar energy fixed, by photosynthesis in green plants • It is measured per unit area per unit time. 5/1/2013 Author-Guru Ecosystem IB /ESS 51
  • 52. • Energy enters an ecosystem through sunlight. • Only 2% of the light energy falling on a tree is captured and turned into chemical energy (glucose) by photosynthesis. • The rest is reflected, or just warms up the tree as it is absorbed. 5/1/2013 Author-Guru Ecosystem IB /ESS 52
  • 53. Ocean Area vs Productivity 5/1/2013 Author-Guru Ecosystem IB /ESS 53
  • 54. Effects of Depth 5/1/2013 Author-Guru Ecosystem IB /ESS 54
  • 55. 5/1/2013 Author-Guru Ecosystem IB /ESS 55
  • 56. Net Productivity • Net productivity is the gain in energy per unit time that remains after deductions due to respiration • Net productivity is the amount of energy trapped in organic matter during a specified interval at a given tropic level less that lost by the respiration of the organisms at that level. 5/1/2013 Author-Guru Ecosystem IB /ESS 56
  • 57. 5/1/2013 Author-Guru Ecosystem IB /ESS 57
  • 58. 5/1/2013 Author-Guru Ecosystem IB /ESS 58
  • 59. Net Primary Productivity (NPP) • The quantity of biomass potentially available to consumers in an ecosystem. • It is measured in unit of mass or energy per unit area per unit time. • Plants have to use some of the energy they capture to keep themselves growing and alive (metabolism). NPP = GPP - respiration 5/1/2013 Author-Guru Ecosystem IB /ESS 59
  • 60. NET PRODUCTIVITY (NP) • is the gain in energy or biomass per unit time remaining after allowing for respiratory loss. • Organisms use some of the energy they capture to keep themselves growing and alive (metabolism). • The energy used by organisms for essential tasks is called RESPIRATORY ENERGY, and eventually it is released to the environment as heat. 5/1/2013 Author-Guru Ecosystem IB /ESS 60
  • 61. NP = GP – respiration (for both producers and consumers) When energy is released from ATP it is lost as heat. (2nd Law of Thermodynamics) 5/1/2013 Author-Guru Ecosystem IB /ESS 61
  • 62. What is Net Productivity? • Some of GPP used to stay alive, grow and reproduce • NPP is what’s left • Most NPP – Estuaries, swamps, tropical rainforests • Least NPP – Open ocean, tundra, desert • Open ocean has low NPP but its large area gives it more NPP total than anywhere else 5/1/2013 Author-Guru Ecosystem IB /ESS 62
  • 63. JANUARY-FEBRAURY SUMMATIVE • • • • • • • • • Date : 6th February, Wednesday Syllabus-The EcosystemUnit 2.5-Function Marks-45 Time :1 hour Paper 1 Formative: Holiday homework Worksheet 5/1/2013 Author-Guru Ecosystem IB /ESS 63
  • 64. 5/1/2013 Author-Guru Ecosystem IB /ESS 64
  • 65. Agricultural Land • Highly modified, maintained ecosystems • Goal is increasing NPP and biomass of crop plants • Add in water (irrigation), nutrients (fertilizer) • Nitrogen and phosphorous are most often limiting to crop growth • Despite modification NPP in agricultural land is less than many other ecosystems 5/1/2013 Author-Guru Ecosystem IB /ESS 65
  • 66. 5/1/2013 Author-Guru Ecosystem IB /ESS 66
  • 67. 5/1/2013 Author-Guru Ecosystem IB /ESS 67
  • 68. RECAP • • • • What is Productivity? What is GPP? What is NPP? How to measure the GROSS PRIMARY PRODUCTIVITY • How to measure the primary productivity • What is Net Productivity? 5/1/2013 Author-Guru Ecosystem IB /ESS 68
  • 69. Secondary Productivity The rate at which herbivores produce new biomass through growth and reproduction. As a rule of thumb, only 10 percent of plant matter is converted to herbivore tissue. The remainder is either not ingested, not digested (and thus passed through an animal to be eliminated as feces) or released as heat. 5/1/2013 Author-Guru Ecosystem IB /ESS 69
  • 70. 5/1/2013 Author-Guru Ecosystem IB /ESS 70
  • 71. SECONDARY PRODUCTIVITY (SP) • biomass gained by heterotrophic organisms through feeding and absorption. • Not all food eaten is absorbed (assimilated) into an animals body. • Unassimilated food = feces or droppings SP = food eaten – fecal loss 5/1/2013 Author-Guru Ecosystem IB /ESS 71
  • 72. In a food web you can usually assume that: • The energy input into an organism = GP. • The energy output to the next trophic level = NP. • The difference between GP and NP = R and/or loss to decomposers. 5/1/2013 Author-Guru Ecosystem IB /ESS 72
  • 73. Secondary Production Secondary production is the amount of biomass at higher trophic levels (the consumer production). It represents the amount of chemical energy in consumers’ food that is converted to their own new biomass. Energy transfers between producers and herbivores, and between herbivores and higher level consumers is Author-Guru 5/1/2013 inefficient. Ecosystem Herbivores (1 consumers)... IB /ESS Eaten by 2 consumers 73
  • 74. Ecological Efficiency The percentage of energy transferred from one trophic level to the next varies between 5% and 20% and is called the ecological Plant material consumed by caterpillar efficiency. 200 J An average figure of 10% is often used. This ten percent law states that the total energy content of a trophic level in an ecosystem is only about one-tenth that of the preceding level. 100 J Feces 5/1/2013 Author-Guru Ecosystem 33 J Growth IB /ESS 67 J Cellular respiration 74
  • 75. Measuring Primary Productivity 1. Harvest method - measure biomass and express as biomass per unit area per unit time. 2. CO2 assimilation - measure CO2 uptake in photosynthesis and release by respiration. 3. O2 production - Measure O2 production and consumption. 5/1/2013 Author-Guru Ecosystem IB /ESS 75
  • 76. Measuring Primary Productivity 4. Radioisotope method - use C14 tracer in photosynthesis. 5. Chlorophyll measurement - assumes a correlation between amount of chlorophyll and rate of photosynthesis. 5/1/2013 Author-Guru Ecosystem IB /ESS 76
  • 77. What affects productivity? 1. 2. 3. 4. 5. 6. 5/1/2013 Solar radiation Temperature CO2 H2O Nutrients Herbivory Author-Guru Ecosystem IB /ESS 77
  • 78. Therefore… • The least productive ecosystems are those with limited heat and light energy, limited water and limited nutrients. • The most productive ecosystems are those with high temperatures, lots of water, light and nutrients. 5/1/2013 Author-Guru Ecosystem IB /ESS 78
  • 79. Biome Productivity Estuaries Swamps and marshes Tropical rain forest Temperate forest Northern coniferous forest (taiga) Savanna Agricultural land Woodland and shrubland Temperate grassland Lakes and streams Continental shelf Open ocean Tundra (arctic and alpine) Desert scrub Extreme desert 800 1,600 2,400 3,200 4,000 4,800 5,600 6,400 7,200 8,000 8,800 9,600 Average net primary productivity (kcal/m2/yr) 5/1/2013 Author-Guru Ecosystem IB /ESS 79
  • 80. Three years of satellite data on the earth’s GP. LAND: high = dark green low = yellow 5/1/2013 OCEAN: high = red low/ESSblue = Author-Guru IB Ecosystem 80
  • 81. 73% Not used by humans Human use of biomass produced by photosynthesis (NPP). 3% Used directly 8% Lost or degraded land 5/1/2013 16% Altered /ESShuman activity IB by Author-Guru Ecosystem 81
  • 82. 5/1/2013 Author-Guru Ecosystem IB /ESS 82
  • 83. Productivity Calculations Total Primary Production = (NPP) Gross Primary Production • Amount of light energy converted into chemical energy by photosynthesis per unit time – Joules / Meter2 / year • Net Primary Production  GPP – R, or GPP – some energy used for cell respiration in the primary producers. • Represents the energy storage available for the whole community of consumers • Standing crop = Total living material at a trophic level 5/1/2013 Author-Guru Ecosystem IB /ESS 83
  • 84. Producers • NPP = GPP – R Consumers • GSP = Food eaten – fecal losses • NSP = change in mass over time • NSP = GSP – R 5/1/2013 Author-Guru Ecosystem IB /ESS 84
  • 85. Measuring Primary Production – Measure aspects of photosynthesis – In closed container measure O2 production, CO2 uptake over time – Must measure starting amount in environment then amount added by producers – Use dissolved oxygen probe or carbon dioxide sensor – Measure indirectly as biomass of plant material produced over time (only accurate over long timer periods)  this gives NPP 5/1/2013 Author-Guru Ecosystem IB /ESS 85
  • 86. • Measuring Aquatic Primary Production using the Light and Dark Bottle Method 5/1/2013 Author-Guru Ecosystem IB /ESS 86
  • 87. TRANSPARENT BOTTLE(LIGHT BOTTLE) OPAQUE BOTTLE(DARK BOTTLE) 5/1/2013 Author-Guru Ecosystem IB /ESS 87
  • 88. Light and Dark Bottle Method – for Aquatic Primary Production • Changes in dissolved oxygen used to measure GPP and NPP • Measures respiration and photosynthesis • Measure oxygen change in light and opaque bottles • Incubation period should range from 30 minutes to 24 hours • Use B.O.D. bottles 5/1/2013 Author-Guru Ecosystem IB /ESS 88
  • 89. • Take two sets of samples measure the initial oxygen content in each (I) • Light (L) and Dark (D) bottles are incubated in sunlight for desired time period • NPP = L – I • GPP = L – D • R= D–I 5/1/2013 Author-Guru Ecosystem IB /ESS 89
  • 90. Sample Data 5/1/2013 Author-Guru Ecosystem IB /ESS 90
  • 91. Method evaluation • Tough in unproductive waters or for short incubation times • Accuracy in these cases can be increased by using radioactive isotopes C14 of carbon • Radioactivity measured with scintillation counter 5/1/2013 Author-Guru Ecosystem IB /ESS 91
  • 92. Can use satellite imaging: Nutrient rich waters of the north Atlantic 5/1/2013 Author-Guru Ecosystem IB /ESS 92
  • 93. Measuring Secondary Productivity • Gross Secondary Production – Measure the mass of food intake (I) by an organism (best if controlled diet in lab) – Measure mass of waste (W) (excrement, shedding, etc.) produced – GSP = I – W • Net Secondary Production – Measure organism’s starting mass (S) and ending mass (E) for experiment duration – NSP = E-S Author-Guru IB /ESS 5/1/2013 Ecosystem 93
  • 94. Method evaluation • GSP method difficult in natural conditions • Even in lab hard to get exact masses for waste • NSP method hard to document mass change in organism unless it is over a long time period 5/1/2013 Author-Guru Ecosystem IB /ESS 94
  • 95. What types of things effect productivity? • What can we measure for an experiment? – Effects of light exposure – strength, time, color, … – Effects of temperature – Differences between types of plants – Differences between types of producers – Effects of nutrient additions – Effects of salinity 5/1/2013 Author-Guru Ecosystem IB /ESS 95
  • 96. Other parameters to change • • • • Terrestrial vs. aquatic Oxygen, carbon dioxide Biomass B.O.D. bottles 5/1/2013 Author-Guru Ecosystem IB /ESS 96
  • 97. GPP estimates 5/1/2013 Author-Guru Ecosystem IB /ESS 97
  • 98. How to Calculate GPP &NPP • Calculate the values of both gross primary • Productivity (GPP) and net primary • Productivity (NPP) from given data. NPP = GPP – R where R = respiratory loss 5/1/2013 Author-Guru Ecosystem IB /ESS 98
  • 99. How to Calculate GSP &NSP • • • • • • Calculate the values of both gross secondary Productivity (GSP) and net secondary Productivity (NSP) from given data. NSP = GSP – R GSP = food eaten – fecal loss where R = respiratory loss 5/1/2013 Author-Guru Ecosystem IB /ESS 99
  • 100. March summative • • • • • Date :15 March,2013 Format: Paper 2 Total Marks-65 Syallabus:Ecosystem Time :3:30pm -5:30pm 5/1/2013 Author-Guru Ecosystem IB /ESS 100
  • 101. March Formative • Collect four different types of feather and name it. Marks will be given based on • Presentation • Naming the bird • Decoration of the chart • Submission on Date 5/1/2013 Author-Guru Ecosystem IB /ESS 101
  • 102. 2.6.1-.2 Populations 5/1/2013 Author-Guru Ecosystem IB /ESS 102
  • 103. Topic -2.6 CHANGES 5/1/2013 Author-Guru Ecosystem IB /ESS 103
  • 104. What is POPULATION CURVE? • The curve which is use to describe the population of an particular animals in an ecosystem is called POPULATION CURVE 5/1/2013 Author-Guru Ecosystem IB /ESS 104
  • 105. What are the main factors that affect the growth of a population?  The main factors that make populations grow are births and immigration.(The action of coming to live permanently)  The main factors that make populations decrease are deaths and emigration.(moving from one place) 5/1/2013 Author-Guru Ecosystem IB /ESS 105
  • 106. What is Exponential growth? • Exponential population growth is when the birth rate is constant over a period of time and isn't limited by food or disease 5/1/2013 Author-Guru Ecosystem IB /ESS 106
  • 107. • Two types of population curve • S Population Curve • J Population Curve 5/1/2013 Author-Guru Ecosystem IB /ESS 107
  • 108. TYPES OF POPULATION CURVE • Two modes of population growth. • J-Shape curve is also known as- Exponential curve occurs when there is no limit to population size. 5/1/2013 Author-Guru Ecosystem IB /ESS 108
  • 109. • S-Shape curve is also known as - Logistic curve shows the effect of a limiting factor • S-Sigmoid 5/1/2013 Author-Guru Ecosystem IB /ESS 109
  • 110. 5/1/2013 Author-Guru Ecosystem IB /ESS 110
  • 111. What is S-Shaped Curve? • In S - shaped or sigmoid growth the population show an initial gradual increase in population size in an ecosystem, followed by an exponential increase and then a gradual decline to near constant level. 5/1/2013 Author-Guru Ecosystem IB /ESS 111
  • 112. • In population of an ecosystem which factors determining the S shape curve? 5/1/2013 Author-Guru Ecosystem IB /ESS 112
  • 113. The curve obtained by plotting growth and time is called a growth curve. It is a typical sigmoid or S- shaped curve. 5/1/2013 Author-Guru Ecosystem IB /ESS 113
  • 114. • • I. What is J shaped? A curve on a graph that records the situation in which, in a new environment, the population density of an organism increases rapidly but then stops abruptly as environmental resistance It may be summarized mathematically as: dN/dt = rN (with a definite limit on N) II. where N is the number of individuals in the population, t is time, and III. r is a constant representing the rate of increase for the organism concerned. 5/1/2013 Author-Guru Ecosystem IB /ESS 114
  • 115. • The growth of population is measured as increase in its size over a period of time and populations show characteristic patterns of growth with time. • These patterns are known as population growth Author-Guru IB /ESS forms. 5/1/2013 Ecosystem 115
  • 116. 5/1/2013 Author-Guru Ecosystem IB /ESS 116
  • 117. RECAP • What is POPULATION CURVE? • What are the main factors that affect the growth of a population? • What are the types of population curve? • What is S shaped? • What is J shaped? • What are the different stages of S shaped curve? 5/1/2013 Author-Guru Ecosystem IB /ESS 117
  • 118. • Area: 430 square kilometers • Population :2500 rhinoceros • It can hold up to 4000 Rhinoceros 5/1/2013 Author-Guru Ecosystem IB /ESS 118
  • 119. 5/1/2013 Author-Guru Ecosystem IB /ESS 119
  • 120. CARRYING CAPACITY • The population that can be supported indefinitely by an ecosystem without destroying that ecosystem 5/1/2013 Author-Guru Ecosystem IB /ESS 120
  • 121. 5/1/2013 Author-Guru Ecosystem IB /ESS 121
  • 122. 5/1/2013 Author-Guru Ecosystem IB /ESS 122
  • 123. What is Carrying Capacity? • The carrying capacity (K) is the maximum number of a species that the habitat can hold. • Once the carrying capacity is reached, unless the environmental resistance is changed, e.g. by a new disease, the size of the population will only fluctuate slightly. 5/1/2013 Author-Guru Ecosystem IB /ESS 123
  • 124. ‘S’ Curves • This is the type of graph that is almost always seen in nature. • As the energy resources become more scarce the population size levels off at the carrying capacity (K). 5/1/2013 Author-Guru Ecosystem IB /ESS 124
  • 125. ‘J’ Curves 5/1/2013 Author-Guru Ecosystem IB /ESS 125
  • 126. ‘J’ Curves • ‘J’ curve example, a population establishing themselves in a new area will undergo rapid exponential growth. • This type of growth produces a J shaped growth curve. • If the resources of the new habitat were endless then the population would continue to increase at this rate. 5/1/2013 Author-Guru Ecosystem IB /ESS 126
  • 127. ‘J’ Curves • This type of population growth is rarely seen in nature. • Initially exponential growth will occur but eventually the increase in numbers will not be supported by the environment. • . 5/1/2013 Author-Guru Ecosystem IB /ESS 127
  • 128. March summative • • • • • Date :15 March,2013 Format: Paper 2 Total Marks-65 Syallabus:Ecosystem Time :3:30pm -5:30pm 5/1/2013 Author-Guru Ecosystem IB /ESS 128
  • 129. March Formative • Collect four different types of feather and name it. Marks will be given based on • Presentation • Naming the bird • Decoration of the chart • Submission on Date 5/1/2013 Author-Guru Ecosystem IB /ESS 129
  • 130. RECAP • What is CARRYING CAPACITY? • Example of Carrying capacity • Which type of curve is common in nature? Why? • Why J curve is not common in the nature? 5/1/2013 Author-Guru Ecosystem IB /ESS 130
  • 131. Population Growth Change in the size of a population over time. 5/1/2013 Author-Guru Ecosystem IB /ESS 131
  • 132. • POPULATION = a group of interbreeding organisms (same species) that live in the same place at the same time and compete for the same resources. • Resources = food, water, shelter, mates, and so on . .. • pop. size • 5/1/2013 resources  resources  pop. size Author-Guru Ecosystem IB /ESS 132
  • 133. Populations change in response to environmental stress or changes in environmental conditions. 1. In size = # of individuals 2. Density = # of individual / specific space 3. Age distribution = proportions / age group 4. Dispersion 5/1/2013 Clumped (elephants) Uniform IB /ESS Author-Guru (creosote bush) Ecosystem Random (dandelions) 133
  • 134. No population can grow indefinitely! Number of sheep (millions) Every environment has a CARRYING CAPACITY = the maximum number of individuals of a given species that can be sustained indefinitely in a given space. 2.0 5/1/2013 1.5 1.0 .5 Author-Guru 1800 Ecosystem IB /ESS 1825 1850 1875 Year 1900 1925134
  • 135. Factors that affect carrying capacity: 1. 2. 3. 4. 5/1/2013 Competition with/in and between species. Natural and human caused catastrophes. Immigration and emigration. Seasonal fluctuations in food, water, shelter, and nesting sites. Author-Guru Ecosystem IB /ESS 135
  • 136. “J” population growth curve 5/1/2013 Population size (N) A population that has few if any resource limitations grows exponentially. EXPONENTIAL GROWTH starts out slowly and then proceeds faster and faster as the population increases. Author-Guru Ecosystem IB /ESS Time (t) 136
  • 137. Bacteria population 24 hours later 1024 8 5/1/2013 Author-Guru Ecosystem IB /ESS 137
  • 138. 5/1/2013 Author-Guru Ecosystem IB /ESS 138
  • 139. LOGISTIC GROWTH involves initial exponential growth and then there is a steady decrease in growth as the population encounters environmental resistance and approaches carrying capacity and levels off. “S or sigmoid” population growth curve 5/1/2013 Population size (N) K Author-Guru Ecosystem IB /ESS Time (t) 139
  • 140. Plateau phase K Population size (N) Transitional phase 5/1/2013 Exponential phase Time (t)IB /ESS Author-Guru Ecosystem 140
  • 141. Kaibab Plateau 5/1/2013 Author-Guru Ecosystem IB /ESS 141
  • 142. Number of reindeer 2,000 1,500 1,000 500 1910 5/1/2013 1920 1930 Year IB /ESS Author-Guru Ecosystem 1940 1950 142
  • 143. Kaibab Plateau 5/1/2013 Author-Guru Ecosystem IB /ESS 143
  • 144. 5/1/2013 Author-Guru Ecosystem IB /ESS 144
  • 145. March summative • • • • • Date :4th April,2013 Format: Paper 2 Total Marks-40 Syallabus:Ecosystem Two Essay Type Questions 5/1/2013 Author-Guru Ecosystem IB /ESS 145
  • 146. March Formative • Collect four different types of feather and name it. Marks will be given based on • Presentation • Naming the bird • Decoration of the chart • Submission on Date 5/1/2013 Author-Guru Ecosystem IB /ESS 146
  • 147. 2.6.1- Population Dynamics 5/1/2013 Author-Guru Ecosystem IB /ESS 147
  • 148. TWO TYPES OF SPECIES • r-selected species • K-selected species • r-selected species live in variable or unpredictable environments • K-selected species live in fairly constant or predictable environment 5/1/2013 Author-Guru Ecosystem IB /ESS 148
  • 149. Examples of r-selected species • Examples of r-selected species include pest organisms, such as rodents, insects, Mosquitoes and Weeds. • r-selected species thrive in disturbed habitats, such as freshly burned grasslands or forests characterized by canopies that open abruptly, such as when a forest’s tallest trees have been knocked down by a windstorm 5/1/2013 Author-Guru Ecosystem IB /ESS 149
  • 150. 5/1/2013 Author-Guru Ecosystem IB /ESS 150
  • 151. 5/1/2013 Author-Guru Ecosystem IB /ESS 151
  • 152. Examples of K-selected species • Examples of K-selected species include birds, larger mammals (such as elephants, horses, and primates), and larger plants. 5/1/2013 Author-Guru Ecosystem IB /ESS 152
  • 153. K & R STRAEGIST • Species of organism that uses a survival and reproductive 'strategy' characterised by low mortality, longer life and with populations approaching the carrying capacity of the environment, controlled by density-dependent factors. 5/1/2013 Author-Guru Ecosystem IB /ESS 153
  • 154. • What is Density-Dependent Factors? • A limiting factor that depends on population size is called a density-dependent limiting factor. 5/1/2013 Author-Guru Ecosystem IB /ESS 154
  • 155. What is Density Dependent Factors • Increasing population size reduces available resources limiting population growth. • In restricting population growth, a densitydependent factor intensifies as the population size increases, affecting each individual more strongly. • Population growth declines because of death rate increase, birth rate decrease or both. 5/1/2013 Author-Guru Ecosystem IB /ESS 155
  • 156. • Density-dependent limiting factors include: 1. Competition 2. Predation 3. Parasitism 4. Disease 5/1/2013 Author-Guru Ecosystem IB /ESS 156
  • 157. • Examples of densitydependent limiting factors include: 1. Unusual weather 2. Natural disasters 3. Seasonal cycles 4. Certain human activities—such as damming rivers and clear-cutting forests 5/1/2013 Author-Guru Ecosystem IB /ESS 157
  • 158. How this related to Ecology? In ecology, r/K selection theory relates to the selection of combinations of traits that trade off the quantity and quality of offspring to promote success in particular environments. The terminology of r/K-selection was coined by the ecologists Robert MacArthur and E. O. Wilson based on their work on island biogeography. 5/1/2013 Author-Guru Ecosystem IB /ESS 158
  • 159. Robert MacArthur E. O. Wilson 5/1/2013 Author-Guru Ecosystem IB /ESS 159
  • 160. 5/1/2013 Author-Guru Ecosystem IB /ESS 160
  • 161. 5/1/2013 Author-Guru Ecosystem IB /ESS 161
  • 162. 5/1/2013 Author-Guru Ecosystem IB /ESS 162
  • 163. 5/1/2013 Author-Guru Ecosystem IB /ESS 163
  • 164. 5/1/2013 Author-Guru Ecosystem IB /ESS 164
  • 165. STABLE & UNSTABLE ENVIRONMENTS • Organisms that live in stable environments tend to make few, "expensive" offspring. • Organisms that live in unstable environments tend to make many, "cheap" offspring. 5/1/2013 Author-Guru Ecosystem IB /ESS 165
  • 166. EXAMPLE • Imagine that you are one of the many invertebrate organisms which existed during the Cambrian or one of their descendents living today. • Maybe you live in a tide pool which is washed by waves. • A storm appears on the horizon. • The waves increase in height. • You feel yourself being dashed upon the rocks or into the mouth of a much larger and predatory animal. • Finally, you begin to see your brothers and sisters die, one by one, as the forces of nature change your unpredictable environment. 5/1/2013 Author-Guru Ecosystem IB /ESS 166
  • 167. • If you could design a "strategy" to overcome the problems created by an unpredictable environment, you would have two choices - go with the flow or cut and run to a more stable environment. 5/1/2013 Author-Guru Ecosystem IB /ESS 167
  • 168. • Suppose you stayed. Then, one thing you could do would be to increase the number of offspring. • Make lots of cheap (requiring little energy investment) offspring instead of a few expensive, complicated ones (requiring a lot of energy investment). • If you lose a lot of offspring to the unpredictable forces of nature, you still have some left to live to reproductive age and pass on your genes to future generations. • Many invertebrates follow this strategy - lots of eggs are produced and larvae are formed but only a few survive to produce mature, reproductive adults. Many insects and spiders also follow this strategy. 5/1/2013 Author-Guru Ecosystem IB /ESS 168
  • 169. • Alternatively, you could adapt to a more stable environment. • If you could do that, you would find that it would be worthwhile to make fewer, more expensive offspring. • These offspring would have all the bells and whistles necessary to ensure a comfortable, maximally productive life. • Since the environment is relatively stable, your risk of losing offspring to random environmental factors is small. Large animals, such as ourselves, follow this strategy. 5/1/2013 Author-Guru Ecosystem IB /ESS 169
  • 170. Mortality, Survivorship, & Competition • In r-selected species mortality is often catastrophic and subject to density independent limiting factors. • Survivorship is low early in life but increases for those individuals surviving (Type III). Competition lax. • In K-selected species mortality is subject to density dependent limiting factors Survivorship is high throughout life until late in life (Type I). Competition keen. 5/1/2013 Author-Guru Ecosystem IB /ESS 170
  • 171. Population Size • In r-selected species, population size tends to vary in time and recolonization occur into unpopulated area frequently (pioneer species) • In K-selected species, population size is usually at or near the carrying capacity and colonization is infrequent (keystone species in climax communities) 5/1/2013 Author-Guru Ecosystem IB /ESS 171
  • 172. r Species Selection Factors • • • • • • • Rapid Development High r = or net reproductive rate Early Reproduction Small Body Size Single Reproduction Many Small Offspring Short Life Span 5/1/2013 Author-Guru Ecosystem IB /ESS 172
  • 173. K Species Selection Factors • • • • • • • Slow Development Competitive Ability Delayed Reproduction Large Body Size Repeated Reproduction Few Large Offspring Long Life Span 5/1/2013 Author-Guru Ecosystem IB /ESS 173
  • 174. March summative • • • • • Date :4th April,2013 Format: Paper 2 Total Marks-40 Syallabus:Ecosystem Two Essay Type Questions 5/1/2013 Author-Guru Ecosystem IB /ESS 174
  • 175. RECAP • • • • • • • • What is r selected species? Example What is K selected species? Example What is Density-Dependent Factors? Factors which includes Density-dependent limiting are… How r/K species related to Ecology? What is Stable &unstable Environment r Species Selection Factors K Species Selection Factors 5/1/2013 Author-Guru Ecosystem IB /ESS 175
  • 176. What is difference between r &K? K 1. Growth Pattern - large body, long juvenile period; Population grows exponentially and then stabilizes around a max value 2. Population Size - smaller, but stable 3. Environment - stable, diverse ecology 4. Reproductive strategy - mate choice, pair bonds, large investment, parental care, few offspring 5. Characteristics of offspring -They're born more dependent on the parents and stay that way longer; later onset of repro maturity • Examples - Elephants, humans, oak trees. 5/1/2013 Author-Guru Ecosystem IB /ESS 176
  • 177. 1. r Growth Pattern - small body, rapid maturation; population grows exponentially then crashes 2. Population Size - large, but rapid fluctuation 3. Environment - unstable, recently disrupted, low diversity, low resources 4. Reproductive strategy - maximize number of offspring, low parental investment, random mating 5. Characteristics of offspring - independent right away, early reproductive maturity, large numbers 6. Examples - weeds, mosquitoes, mice 5/1/2013 Author-Guru Ecosystem IB /ESS 177
  • 178. • In the scientific literature, r-selected species are occasionally referred to as "opportunistic", while K-selected species are described as "equilibrium 5/1/2013 Author-Guru Ecosystem IB /ESS 178
  • 179. Population Dynamics Factors that tend to increase or decrease the size of a population. 5/1/2013 Author-Guru Ecosystem IB /ESS 179
  • 180. The population size of a species in a given space at a given time is determined by the interplay between BIOTIC POTENTIAL and ENVIRONMENTAL RESISTANCE. Biotic potential = growth rate with unlimited resources. Environmental resistance = all the factors acting jointly to limit population growth. 5/1/2013 Author-Guru Ecosystem IB /ESS 180
  • 181. POPULATION SIZE Growth factors (biotic potential) Abiotic Favorable light Favorable temperature Favorable chemical environment (optimal level of critical nutrients) Biotic 5/1/2013 Decrease factors (environmental resistance) Abiotic Too much or too little light Temperature too high or too low Unfavorable chemical environment (too much or too little of critical nutrients) Biotic High reproductive rate Low reproductive rate Generalized niche Specialized niche Adequate food supply Inadequate food supply Suitable habitat Unsuitable or destroyed habitat Ability to compete for resources Too many competitors Insufficient ability to hide from or defend Ability to hide from or defend against predators against predators Ability to resist diseases and parasites Inability to resist diseases and parasites Ability to migrate and live in other Inability to migrate and live in other habitats habitats IB /ESS Ability to adapt to environmental Author-Guru Inability to adapt to environmental Ecosystem change change 181
  • 182. Four variables change population size: 1. NATALITY = birth rate 2. MORTALITY = death rate 3. IMMIGRATION = rate of organisms moving in 4. EMIGRATION = rate of organisms moving out 5/1/2013 Author-Guru Ecosystem IB /ESS 182
  • 183. REPRODUCTIVE STRATEGIES Carrying capacity K Number of individuals K species; experience K selection r species; experience r selection 5/1/2013 Author-Guru Ecosystem Time IB /ESS 183
  • 184. Opportunistic or r-Selected Species cockroach dandelion Many small offspring Little or no parental care and protection of offspring Early reproductive age Most offspring die before reaching reproductive age Small adults Adapted to unstable climate and environmental conditions High population growth rate (r) Population size fluctuates wildly above and below carrying capacity (K) Generalist niche Low ability to compete Early successional species 5/1/2013 Author-Guru Ecosystem IB /ESS 184
  • 185. Competitor or K-Selected Species elephant saguaro Fewer, larger offspring High parental care and protection of offspring Later reproductive age Most offspring survive to reproductive age Larger adults Adapted to stable climate and environmental conditions Lower population growth rate (r) Population size fairly stable and usually close to carrying capacity (K) Specialist niche High ability to compete Late successional species 5/1/2013 Author-Guru Ecosystem IB /ESS 185
  • 186. SURVIVORSHIP CURVES 5/1/2013 Author-Guru Ecosystem IB /ESS 186
  • 187. Population density affects population growth. 5/1/2013 Author-Guru Ecosystem IB /ESS 187
  • 188. DENSITY INDEPENDENT FACTORS = affect a populations’ size regardless of its population density. 1. Weather 2. Earthquakes 3. Floods 4. Fires . . . Natural disasters R-strategists populations are most affected by these. 5/1/2013 Author-Guru Ecosystem IB /ESS 188
  • 189. DENSITY DEPENDENT FACTORS = affect a populations’ size depending on its population density. 1. Predation 2. Disease 3. Availability of food and water 4. Space Negative Feedback!! 5/1/2013 Author-Guru Ecosystem IB /ESS 189
  • 190. INTERNAL FACTORS = might include densitydependent fertility or size of breeding territory. EXTERNAL FACTORS = might include predation and disease. 5/1/2013 Author-Guru Ecosystem IB /ESS 190
  • 191. Species interactions influence population growth and carrying capacity = SYMBIOSIS Competition for resources. High High Relative population density Relative population density Paramecium aurelia Paramecium caudatum Low 0 2 4 6 8 10 12 14 16 18 Paramecium aurelia Paramecium caudatum Low 0 2 Days 5/1/2013 Author-Guru Ecosystem Each species grown alone IB /ESS 4 6 8 10 Days 12 14 Both species grown together 16 191 18
  • 192. Resource Portioning 5/1/2013 Author-Guru Ecosystem IB /ESS 192
  • 193. PREDATION PREY POPULATION PREDATOR POPULATION 5/1/2013 Author-Guru Ecosystem IB /ESS 193
  • 194. Avoiding predators Span worm Wandering leaf insect Poison dart frog Viceroy butterfly mimics monarch butterfly 5/1/2013 Author-Guru Ecosystem Bombardier beetle Hind wings of io moth resemble eyes of a much larger animal IB /ESS Foul-tasting monarch butterfly When touched, the snake caterpillar changes shape to look like the head of a snake 194
  • 195. Parasitism 5/1/2013 Author-Guru Ecosystem IB /ESS 195
  • 196. Mutualism Oxpeckers and black rhinoceros 5/1/2013 Author-Guru Ecosystem Clown fish and sea anemone IB /ESS 196
  • 197. Shark and ramora 5/1/2013 Author-Guru Ecosystem IB /ESS 197
  • 198. Cleaning station Cleaner blenny Sabertooth blenny 5/1/2013 Author-Guru Ecosystem IB /ESS 198
  • 199. Commensalism 5/1/2013 Author-Guru Ecosystem IB /ESS 199
  • 200. Herbivory 5/1/2013 Author-Guru Ecosystem IB /ESS 200
  • 201. Chapter : 2.5.4 Topic : Transfer and Transformation of Materials in Cycle in Eco system 5/1/2013 Author-Guru Ecosystem IB /ESS 201
  • 202. What is Biogeochemical cycle? • The cyclic transformation of chemicals through interacting biological, geological and chemical processes. • Natural processes that recycle nutrients in various chemical forms from the environment, to organisms, and then back to the environment • Ex: carbon, oxygen, nitrogen, phosphorus, and hydrologic cycles. 5/1/2013 Author-Guru Ecosystem IB /ESS 202
  • 203. • The biogeochemical cycles of all elements used by life have both an organic and an inorganic phase. • This cycling involves the decomposition of organic matter back into inorganic nutrients 5/1/2013 Author-Guru Ecosystem IB /ESS 203
  • 204. 5/1/2013 Author-Guru Ecosystem IB /ESS 204
  • 205. What is Carbon Cycle? • The process by which carbon is taken up by plants and animals and returned to the environment in a continuous cycle. • The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, geosphere, hydrosphere, and atmosphere of the Earth. 5/1/2013 Author-Guru Ecosystem IB /ESS 205
  • 206. 5/1/2013 Author-Guru Ecosystem IB /ESS 206
  • 207. Carbon is stored on our planet in the following major sinks 1. As organic molecules in living and dead organisms found in the biosphere; 2. As the gas carbon dioxide in the atmosphere; 3. As organic matter in soils; 4. In the lithosphere as fossil fuels and sedimentary rock deposits such as limestone, 5. In the oceans as dissolved atmospheric carbon dioxide and as calcium carbonate shells in marine organisms. 5/1/2013 Author-Guru Ecosystem IB /ESS 207
  • 208. 5/1/2013 Author-Guru Ecosystem IB /ESS 208
  • 209. 5/1/2013 Author-Guru Ecosystem IB /ESS 209
  • 210. 5/1/2013 Author-Guru Ecosystem IB /ESS 210
  • 211. 5/1/2013 Author-Guru Ecosystem IB /ESS 211
  • 212. 5/1/2013 Author-Guru Ecosystem IB /ESS 212
  • 213. What is Nitrogen cycle ? • A process in which atmospheric nitrogen enters the soil and becomes part of living organisms, and then returns to the atmosphere. • Cyclic movement of nitrogen in different chemical forms from the environment, to organisms, and then back to the environment. 5/1/2013 Author-Guru Ecosystem IB /ESS 213
  • 214. 5/1/2013 Author-Guru Ecosystem IB /ESS 214
  • 215. • Earth's atmosphere is approximately 78-80% nitrogen making it the largest pool of nitrogen. • Most plants can only take up nitrogen in two solid forms: ammonium ion and the nitrate ion . • Most plants obtain the nitrogen they need as inorganic nitrate from the soil solution. • Animals receive the required nitrogen they need for metabolism, growth, and reproduction 5/1/2013 Author-Guru Ecosystem IB /ESS 215
  • 216. 3 PROCESS OF NITROGEN IN THE EARTH • Nitrogen fixation----nitorgen+O2+CO2+H2 • Nitrification---- conversion of ammonia to nitrate • Denitrification-- nitrate becomes molecular(GAS) nitrogen Bacteria 5/1/2013 Author-Guru Ecosystem IB /ESS 216
  • 217. Nitrogen fixation Denitrification Ammonium Nitrate Nitrite bacteria (present in the soil) Nitrogen dioxide Nitrate bacteria Convert into gas with help of bacteria 5/1/2013 Author-Guru Ecosystem DirectlyBacteria present in plant roots starts active on lightening IB /ESS Nitrate 217
  • 218. What is Nitrogen fixation? • Conversion of nitrogen into compounds is essential by combining with carbon, hydrogen and oxygen before it can be absorbed by the plants. This is known as nitrogen fixation • Some fixation occurs in lightning strikes, but most fixation is done by free-living or symbiotic bacteria. • These bacteria have the nitrogenase enzyme that combines gaseous nitrogen with hydrogen to produce ammonia. 5/1/2013 Author-Guru Ecosystem IB /ESS 218
  • 219. 5/1/2013 Author-Guru Ecosystem IB /ESS 219
  • 220. What is Nitrification? • The conversion of ammonia (NH3) to nitrate (NO3-) is called NITRIFICATION • Degradation of ammonia to nitrite is usually the rate limiting step of nitrification. • Nitrification is an important step in the nitrogen cycle in soil 5/1/2013 Author-Guru Ecosystem IB /ESS 220
  • 221. 5/1/2013 Author-Guru Ecosystem IB /ESS 221
  • 222. 5/1/2013 Author-Guru Ecosystem IB /ESS 222
  • 223. What is Denitrification? • The process by which a nitrate becomes molecular nitrogen, especially by the action of bacteria. • The process by which nitrogen, is converted to a gaseous form and lost from the soil or water column. • The reduction of nitrate nitrogen to nitrogen gas. 5/1/2013 Author-Guru Ecosystem IB /ESS 223
  • 224. 5/1/2013 Author-Guru Ecosystem IB /ESS 224
  • 225. Nitrogen Nitrate Nitrogen dioxide Ammonium Nitrate 5/1/2013 Author-Guru Ecosystem IB /ESS 225
  • 226. 5/1/2013 Author-Guru Ecosystem IB /ESS 226
  • 227. 5/1/2013 Author-Guru Ecosystem IB /ESS 227
  • 228. 5/1/2013 Author-Guru Ecosystem IB /ESS 228
  • 229. 5/1/2013 Author-Guru Ecosystem IB /ESS 229
  • 230. actinomycetes 5/1/2013 Author-Guru Ecosystem IB /ESS 230
  • 231. cyanobacteria 5/1/2013 Author-Guru Ecosystem IB /ESS 231
  • 232. • Almost all of the nitrogen found in any terrestrial ecosystem originally came from the atmosphere. • Significant amounts enter the soil in rainfall or through the effects of lightning. • The majority, however, is biochemically fixed within the soil by specialized micro-organisms like bacteria, actinomycetes, and cyanobacteria. 5/1/2013 Author-Guru Ecosystem IB /ESS 232
  • 233. 5/1/2013 Author-Guru Ecosystem IB /ESS 233
  • 234. 5/1/2013 Author-Guru Ecosystem IB /ESS 234
  • 235. 5/1/2013 Author-Guru Ecosystem IB /ESS 235
  • 236. 5/1/2013 Author-Guru Ecosystem IB /ESS 236
  • 237. 5/1/2013 Author-Guru Ecosystem IB /ESS 237
  • 238. What is Water Cycle ? • The cycle of water movement from the atmosphere to the earth and back to the atmosphere through condensation, precipitation, evaporation, and transpiration is called WATER CYCLE • The continual cycle of water between the land, the ocean and the atmosphere. • The water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above and below the surface of the Earth. 5/1/2013 Author-Guru Ecosystem IB /ESS 238
  • 239. 5/1/2013 Author-Guru Ecosystem IB /ESS 239
  • 240. • The four stages in this process are: Evaporation Condensation Precipitation Collection . 5/1/2013 Author-Guru Ecosystem IB /ESS 240
  • 241. 5/1/2013 Author-Guru Ecosystem IB /ESS 241
  • 242. Evaporation • This is the first stage of the water cycle. • The Sun's rays heat the water on the surface of the earth in rivers, oceans and lakes. • This makes the water change into water vapour. 5/1/2013 Author-Guru Ecosystem IB /ESS 242
  • 243. 5/1/2013 Author-Guru Ecosystem IB /ESS 243
  • 244. Condensation : After evaporation, condensation occurs.  Water vapor in the air gets cold and changes back into liquid, forming clouds  The process that causes these changes is called condensation. 5/1/2013 Author-Guru Ecosystem IB /ESS 244
  • 245. • Precipitation : Precipitation occurs when so much water has condensed that the air cannot hold it anymore. The clouds get heavy and water falls back to the earth in the form of rain • Collection After precipitation comes the stage of collection. The raindrops fall back into the lakes, rivers and oceans or are absorbed by the land. This process by which rainwater gathers on earth is called collection. 5/1/2013 Author-Guru Ecosystem IB /ESS 245
  • 246. 5/1/2013 Author-Guru Ecosystem IB /ESS 246
  • 247. 5/1/2013 Author-Guru Ecosystem IB /ESS 247
  • 248. Change in the relative abundance of a species over an area or a distance is referred to as an ECOLOGIAL GRADIENT Also known as Zonation. 5/1/2013 Author-Guru Ecosystem IB /ESS 248
  • 249. What is ZONATION? • Zonation – The arrangement or patterning of plant communities or ecosystems into bands in response to change, over a distance, in some environmental factor. • The main biomes display zonation in relation to latitude and climate. Plant communities may also display zonation with altitude on a mountain, or around the edge of a pond in relation to soil moisture. 5/1/2013 Author-Guru Ecosystem IB /ESS 249
  • 250. School Director Principal Coordinator Teacher 5/1/2013 Author-Guru Ecosystem IB /ESS 250
  • 251. 5/1/2013 Author-Guru Ecosystem IB /ESS 251
  • 252. Heating of solids, sunlight and shade in different altitudinal zones (North hemisphere) 5/1/2013 Author-Guru Ecosystem IB /ESS 252
  • 253. 5/1/2013 Author-Guru Ecosystem IB /ESS 253
  • 254. 5/1/2013 Author-Guru Ecosystem IB /ESS 254
  • 255. What is Environmental gradient? • An environmental gradient is a gradual change in abiotic factors through space (or time). Environmental gradients can be related to factors such as altitude, temperature, depth, ocean proximity and soil humidity. 5/1/2013 Author-Guru Ecosystem IB /ESS 255
  • 256. 5/1/2013 Author-Guru Ecosystem IB /ESS 256
  • 257. Changes in the distribution of animals with elevation on a typical mountain in Kenya. Another example of Zonation 5/1/2013 Author-Guru Ecosystem IB /ESS 257
  • 258. 5/1/2013 Author-Guru Ecosystem IB /ESS 258
  • 259. • In population of an ecosystem which factors determining the J shape curve? 5/1/2013 Author-Guru Ecosystem IB /ESS 259
  • 260. Estimated Net Productivity of Certain Ecosystems (in kilocalories/m2/year) Temperate deciduous forest Tropical rain forest 15,000 Tall-grass prairie Desert Coastal marsh 2,000 500 12,000 Ocean close to shore 2,500 Open ocean 800 Clear (oligotrophic) lake 800 Lake in advanced state of eutrophication 2,400 Silver Springs, Florida 8,800 Field of alfalfa (lucerne) 15,000 Corn (maize) field, U.S. 4,500 Rice paddies, Japan 5,500 Lawn, Washington, D.C. 5/1/2013 5,000 6,800 Sugar cane, Hawaii Author-Guru IB 25,000 /ESS Ecosystem 260
  • 261. 2.6 CHANGES 5/1/2013 Author-Guru Ecosystem IB /ESS 261
  • 262. 5/1/2013 Author-Guru Ecosystem IB /ESS 262
  • 263. 5/1/2013 Author-Guru Ecosystem IB /ESS 263
  • 264. 5/1/2013 Author-Guru Ecosystem IB /ESS 264
  • 265. The series of changes in an ecological community 5/1/2013 Author-Guru Ecosystem IB /ESS 265
  • 266. 5/1/2013 Author-Guru Ecosystem IB /ESS 266
  • 267. • Lichens re composite organisms consisting of a fungus and a photosynthetic partner growing together in a symbiotic relationship. 5/1/2013 Author-Guru Ecosystem IB /ESS 267
  • 268. 5/1/2013 Author-Guru Ecosystem IB /ESS 268
  • 269. 5/1/2013 Author-Guru Ecosystem IB /ESS 269
  • 270. • Mosses are a botanical division (phylum) of small, soft plants that are typically 1–10 cm (0.4–4 in) tall 5/1/2013 Author-Guru Ecosystem IB /ESS 270
  • 271. 5/1/2013 Author-Guru Ecosystem IB /ESS 271
  • 272. 5/1/2013 Author-Guru Ecosystem IB /ESS 272
  • 273. 5/1/2013 Author-Guru Ecosystem IB /ESS 273
  • 274. 5/1/2013 Author-Guru Ecosystem IB /ESS 274
  • 275. In ecology what is succession? • Succession is the process by which a habitat changes over time as different plants get established. • This process can occur from bare rock up to an old-growth forest, and can get reset by a disturbance such as fire. • The path of succession varies from one habitat type to another, but the general idea goes like this: Bare rock ---> Lichens --> Mosses --> Grasses & Forbs --> Brush --> Deciduous hardwood forest -> Mixed deciduous-coniferous forest --> Coniferous forest --> Old growth coniferous forest 5/1/2013 Author-Guru Ecosystem IB /ESS 275
  • 276. What is Ecological succession? • Ecological succession, a fundamental concept in ecology, refers to more or less predictable and orderly changes in the composition or structure of an ecological community. 5/1/2013 Author-Guru Ecosystem IB /ESS 276
  • 277. 5/1/2013 Author-Guru Ecosystem IB /ESS 277
  • 278. Types of succession Two types of Succession • Primary succession • Secondary succession 5/1/2013 Author-Guru Ecosystem IB /ESS 278
  • 279. 5/1/2013 Author-Guru Ecosystem IB /ESS 279
  • 280. 5/1/2013 Author-Guru Ecosystem IB /ESS 280
  • 281. Primary Succession • Primary succession is the series of community changes which occur on an entirely new habitat which has never been colonized before. • Examples of such habitats would include newly exposed or deposited surfaces, such as landslips, volcanic lava and debris, elevated sand banks and dunes, quarried rock faces. • Stages will take place in which an initial or 'pioneer' community will gradually develop through a number of different communities into a 'climax' community, which is the final stage 5/1/2013 Author-Guru Ecosystem IB /ESS 281
  • 282. Coastal Sand Dunes An Example of Primary Succession 5/1/2013 Author-Guru Ecosystem IB /ESS 282
  • 283. • Primary succession is the gradual growth of organisms in an area that was previously bare, such as rock. • For example lichens, mosses, and ferns will first appear on bare rock. • In primary succession pioneer species like mosses, lichen, algae and fungus as well as other abiotic factors like wind and water start to "normalize" the habitat. • This creating conditions nearer optimum for vascular plant growth 5/1/2013 Author-Guru Ecosystem IB /ESS 283
  • 284. the succession of a pond ecosystem to a meadow over 250 years. 5/1/2013 Author-Guru Ecosystem IB /ESS 284
  • 285. 5/1/2013 Author-Guru Ecosystem IB /ESS 285
  • 286. What is Secondary succession? • Secondary succession is the series of community changes which take place on a previously colonized, but disturbed or damaged habitat. Examples include areas which have been cleared of existing vegetation (such as after tree-felling in a woodland) and destructive events such as fires. 5/1/2013 Author-Guru Ecosystem IB /ESS 286
  • 287. 5/1/2013 Author-Guru Ecosystem IB /ESS 287
  • 288. 5/1/2013 Author-Guru Ecosystem IB /ESS 288
  • 289. • Secondary succession can proceed much faster because the soil has already been prepared by the previous community 5/1/2013 Author-Guru Ecosystem IB /ESS 289
  • 290. • Secondary succession is usually much quicker than primary succession for the following reasons: • There is already an existing seed bank of suitable plants in the soil. • Root systems undisturbed in the soil, stumps and other plant parts from previously existing plants can rapidly regenerate. • The fertility and structure of the soil has also already been substantially modified by previous organisms to make it more suitable for growth and colonization. 5/1/2013 Author-Guru Ecosystem IB /ESS 290
  • 291. 5/1/2013 Author-Guru Ecosystem IB /ESS 291
  • 292. 5/1/2013 Author-Guru Ecosystem IB /ESS 292
  • 293. • The mature stage of succession in a particular area, in which all organisms and non living factors are in balance. • Terrestrial communities of organisms move through a series of stages from bare earth or rock to forests of mature trees. • This last stage is described as the "climax" because it is thought that, if left undisturbed, communities can remain in this stage in perpetuity. • However, more recent studies suggest that climax may be only one part of a continuous cycle of successional stages in these communities. 5/1/2013 Author-Guru Ecosystem IB /ESS 293
  • 294. Differences between pioneer and climax communities Pioneer Community Climax Community Unfavorable environment favorable environment biomass increases quickly biomass is generally stable energy consumption inefficient some nutrient loss energy consumption efficient Nutrient cycling and recycling r - strategists K - strategists low species diversity, habitat high species diversity, diversity, genetic diversity habitat diversity, genetic Author-Guru IB /ESS diversity 5/1/2013 Ecosystem 294
  • 295. The following charts summarize the major trends as the ecosystem undergoes succession. Ecosystem characteristic Trends in ecological succession Food chains Simple food chains becoming more complex food webs Relative Species abundance Changes rapidly first, changes slower in the later stages. Total biomass Increasing Humus (non- Increasing living organic matter) Species diversity 5/1/2013 Low diversity in the early stages, then increasing in the intermediate stages /ESS and then stabilizing in the Author-Guru IB 295 Ecosystem final stages as an equilibrium is approached
  • 296. Productivity Ecosystem characteristic Trends in succession Gross productivity (GP) Increasing during early stages of primary succession then little or no increase during final stages of secondary succession Net productivity (NP) Decreasing Respiration (R) Increasing 5/1/2013 Author-Guru Ecosystem IB /ESS ecological 296
  • 297. Mineral and Nutrient cycles Ecosystem characteristic Trends in ecological succession Mineral cycles Becomes more self-contained in later stages Nutrient recycling Increases in later stages 5/1/2013 Author-Guru Ecosystem IB /ESS 297
  • 298. 5/1/2013 Author-Guru Ecosystem IB /ESS 298
  • 299. 1.World Environment Day is observed on which date : 5/1/2013 Author-Guru Ecosystem IB /ESS 299
  • 300. 2.In which year Project Tiger was introduced in India 5/1/2013 Author-Guru Ecosystem IB /ESS 300
  • 301. 3.Which State in India having the highest percentage of forests? 5/1/2013 Author-Guru Ecosystem IB /ESS 301
  • 302. 4.Earth day is observed on which date 5/1/2013 Author-Guru Ecosystem IB /ESS 302
  • 303. 5.Branch of Biology which is concerned with the inter-relationship between plants and animals is called : 5/1/2013 Author-Guru Ecosystem IB /ESS 303
  • 304. 6.Which is the first state to implement the path-breaking proposal that environment should be included as a separate subject in schools? 5/1/2013 Author-Guru Ecosystem IB /ESS 304
  • 305. 7.Name the National Marine animal of India? 5/1/2013 Author-Guru Ecosystem IB /ESS 305
  • 306. 8.Which popular brand takes its name from a particular species of deer native to South Africa? 5/1/2013 Author-Guru Ecosystem IB /ESS 306
  • 307. 9.Which comic character cannot stand trees being cut down? 5/1/2013 Author-Guru Ecosystem IB /ESS 307
  • 308. • 10.Which ancient Indian text contains rules and regulations on how to run a protected forest or a ‘abhayaranya’? 5/1/2013 Author-Guru Ecosystem IB /ESS 308
  • 309. 5/1/2013 Author-Guru Ecosystem IB /ESS 309
  • 310. 1.World Environment Day is observed on which date : June 5 5/1/2013 Author-Guru Ecosystem IB /ESS 310
  • 311. 2.In which year Project Tiger was introduced in India 1973 5/1/2013 Author-Guru Ecosystem IB /ESS 311
  • 312. 3.Which State in India having the highest percentage of forests? Mizoram 5/1/2013 Author-Guru Ecosystem IB /ESS 312
  • 313. 4. Earth day is observed on which date April 22 5/1/2013 Author-Guru Ecosystem IB /ESS 313
  • 314. 5.Branch of Biology which is concerned with the inter-relationship between plants and animals is called : Ecology 5/1/2013 Author-Guru Ecosystem IB /ESS 314
  • 315. 6.Which is the first state to implement the path-breaking proposal that environment should be included as a separate subject in schools? Maharashtra 5/1/2013 Author-Guru Ecosystem IB /ESS 315
  • 316. 7.Name the National Marine animal of India? Gangetic Dolphin 5/1/2013 Author-Guru Ecosystem IB /ESS 316
  • 317. 8.Which popular brand takes its name from a particular species of deer native to South Africa? Reebok 5/1/2013 Author-Guru Ecosystem IB /ESS 317
  • 318. 9.Which comic character cannot stand trees being cut down? Dogmatix of Asterix 5/1/2013 Author-Guru Ecosystem IB /ESS 318
  • 319. • 10.Which ancient Indian text contains rules and regulations on how to run a protected forest or a ‘abhayaranya’? Kautilya’s Arthashastra 5/1/2013 Author-Guru Ecosystem IB /ESS 319
  • 320. • This tree was supposedly brought to India from Sri Lanka by Hanuman when he was carrying messages from Sita. He felt so delighted by it that he threw the seeds on what is presently Maharashtra. Which tree? • The Mango 5/1/2013 Author-Guru Ecosystem IB /ESS 320