Recommended
More Related Content
Similar to 3. Ecosystem.ppt
Similar to 3. Ecosystem.ppt (20)
More from Preeti633690
Recently uploaded
Recently uploaded (20)
3. Ecosystem.ppt
- 1. ECOLOGY Dr. Preeti Kumari Assistant Professor, Amity Institute of Applied Sciences, Amity University, Jharkhand, India -834002.
- 2. ECOLOGY What is ecology? • Ecology (Greek Oikos = home, habitat, logy = study) was coined over a century ago ( by Haeckel). • The word Ecosystem was first coined by British ecologist, A.G. Transley in 1935. Definitions: The study of interaction between biotic and abiotic components is known as Ecology.
- 3. BIOSPHERE The part of Earth that supports life Top portion of Earth's crust All the waters that cover Earth's surface Atmosphere that surrounds Earth.
- 4. BIOSPHERE
- 5. ECOSYSTEM All the organisms living in an area and the nonliving features of their environment
- 7. BIOTIC COMPONENTS The autotrophs (autotrpic = self-nourishing) which can produce their own food. These are green plants (with chlorophyll), blue green algae (BGA), and certain bacteria (chemosynthetic and photosynthetic). Since these organisms produce food for all the other organisms they are also known as producer. Algae of various types are producers of aquatic ecosystem. Terrestrial ecosystem have trees, shrubs, herbs, grasses, and mosses. Since heterotropic organisms depend on plants and other autotropic organisms like bacteria and algae for their nutrition, the amount of energy that the producers capture, sets the limits on the availability of energy for the ecosystem.
- 9. Graphical representation of different trophic levels in any ecosystem. Producers-1st trophic level Herbivores- 2nd trophic level Carnivores- 3rd trophic level Base Apex Producer Herbivores Carnivores
- 10. Ecological Pyramid Pyramid of Number Pyramid of Energy Pyramid of Biomass No. of individual in the different trophic level at any given time is shown Show relationship between different trophic levels of an ecosystem on the basis of living weight (fresh/dry) Amount of energy in the different trophic level at any given time is shown
- 11. PYRAMID OF NUMBER IN GRASSLAND ECOSYSTEM
- 12. PYRAMID OF NUMBER IN TREE ECOSYSTEM
- 14. PYRAMID OF ENERGY Pyramid of energy is always upright.
- 15. POPULATION All the organisms in an ecosystem that belong to the same species
- 17. COMMUNITY All the populations in an ecosystem
- 18. HABITAT The place in which an organism lives provides the kinds of food and shelter, the temperature, and the amount of moisture the organism needs to survive
- 21. COMPETITION Competition caused by population growth affects many organisms, including humans Limits population size
- 22. LIMITING FACTOR Anything that restricts the number of individuals in a population. Includes living and nonliving features of the ecosystem
- 24. SUCCESSION Natural, gradual changes in the types of species that live in an area; can be primary or secondary. Primary – begins in a place without soil Secondary – where soil already exists
- 27. PRIMARY SUCCESSION Begins in bare area, e.g. newly formed island, newly deposited volcanic ash on rock, etc.
- 28. SECONDARY SUCCESSION Begins on secondary area where already life has existed, e.g. cut or burnt out forest, new pond formed after flood, etc.
- 29. PIONEER SPECIES A group of organisms, such as lichens, found in the primary stage of succession and that begin an area's soil-building process
- 31. CLIMAX COMMUNITY A community that has reached a stable stage of ecological succession
- 33. HYDROSERE Newly formed pond or lake Stage 1 • Phytoplankton stage Stage 2 • Submerged stage Stage 3 • Floating stage Stage 4 • Reed swamp stage Stage 5 • Marsh meadow stage Stage 6 • Woodland stage Stage 7 • Climax forest
- 34. XEROSERE Originating on a rock, also called lithosere Stage 1 • Crustose lichen stage Stage 2 • Foliose stage Stage 3 • Moss stage Stage 4 • Herbaceous stage Stage 5 • Shrub stage Stage 7 • Climax forest
- 35. Autotrophs Herbivores Carnivores ENERGY FLOW DIAGRAM OF LAKE D D D NU R NU NU R R D=DECOMPOSITION R=RESPIRATION NU=NOT UTILIZED
- 37. The diagram reveals two important aspects. 1. The flow of energy is unidirectional and non- cyclic in nature. 2. Energy decreases gradually at each trophic level.
- 38. PRODUC ER CONSUM ERS [I- total energy input, LA – light absorbed by plant cover, PG – gross primary production, A – total assimilation, PN – net primary production, P – Secondary production, NU – Energy not used (stored), NA – Energy not assimilated by consumers (egested), R – respiration. Bottom line in the diagram shows the order of the magnitude of energy losses expected at major transfer points, starting with a solar input of 3,000 Kcal per square meter per day. (After E.P. Odum, 1963)]
- 39. The linear energy flow model has significant implications. It highlights that shorter food chains tend to have more energy available at higher trophic levels. This observation highlights the significance of taking into account the length and complexity of food chains when evaluating energy availability in ecosystems.
- 40. FOOD CHAIN The sequence or order of trophic levels through which food energy passes from the primary producers to the top carnivores is called the food chain. Grazing food chain - Starts from living plants and goes through herbivores to carnivores. Grass Rabbit Fox
- 41. FOOD CHAIN Detritus food chain - Starts from dead organic matter and goes through small to larger organisms. Dead leaves on water Worms and snails Small fish Big fish
- 42. FOOD WEB (POND ECOSYSTEM)
- 43. FOOD WEB (GRASSLAND ECOSYSTEM)
- 44. BIOGEOCHEMICAL CYCLE Circulation of materials between the biotic and abiotic components of the ecosystem is called the biogeochemical cycle. Gaseous cycles= C, O, N and water cycle. Reservoir= air, ocean Sedimentary cycle= P and S cycle. Reservoir= earth’s crust
- 45. WATER CYCLE (HYDROLOGICAL CYCLE)
- 46. CARBON CYCLE CO2 in atmosphere CO2 in water Firewoods Land plants Land animals Coal deposits Limestone rocks Volcanoes Lime deposites in water Microbes in the soil Aquatic plants Aquatic animals
- 47. NITROGEN CYCLE
- 50. BIOME Large geographic areas with similar climates and ecosystems
- 51. Biome Large scale areas of similar vegetation and climatic characteristics. A fundamental classification of biomes is: 1. Terrestrial (land) biomes 2. Aquatic biomes (including Freshwater biomes and Marine biomes). Climate is a major factor determining the distribution of terrestrial biomes. Freshwater Marine Desert Forest Grassland Tundra Here we group biomes into six major types:
- 53. DIFFERENT TYPES OF BIOMES - INCLUDES 1) Tundra 2) Taiga 3) Desert 4) Temperate deciduous forest 5) Temperate rain forest 6) Tropical rain forest, and grassland
- 54. ICE SHEET AND POLAR DESERTS
- 55. TUNDRA
- 56. TAIGA
- 57. MONTANE
- 58. MIXED AND DECIDUOUS FOREST
- 60. STEPPE
- 61. SAVANNA
- 62. DESERT
- 64. THANK YOU
Editor's Notes
- Green plants, or autotrophs, take in energy from the sun through photosynthesis and convert it into chemical energy. Plant tissues store this energy and then transform it into heat energy during metabolic activities. Afterwards, it is transferred to the next trophic level in the food chain. The solar energy captured by autotrophs does not return to the sun; instead, it travels through the ecosystem, reaching herbivores and subsequently consumers. The functioning of biological systems is dependent on this unidirectional flow of energy. The entire ecosystem would collapse without a primary energy source. The transfer of energy from one trophic level to another causes a significant loss of heat through metabolic reactions. Additionally, the organisms utilize some of the energy at each trophic level for their various biological processes.
- When considering the Single Channel Energy Flow Model, it becomes evident that the flow of energy in an ecosystem decreases significantly at each successive trophic level. The reason for this reduction is energy losses in the form of heat or other unusable forms. Considering the total energy flow, which includes primary productivity and respiration, or focusing solely on secondary productivity, there is a gradual decrease in energy flow. For instance, out of the 3,000 Kcal of total light energy falling upon green plants, approximately 50% is absorbed, 1% is converted at the first trophic level, resulting in a net primary production of only 15 Kcal. As we move up the trophic levels, secondary productivity tends to be around 10% for successive consumer levels, although it may occasionally reach 20% at the carnivore level.
- The first law of thermodynamics states that energy cannot be created or destroyed but can be converted from one form to another. In the context of energy transfer in ecosystems, there is a degradation of energy from a concentrated form, such as mechanical or chemical energy, to a dispersed form, primarily as heat. The second law of thermodynamics emphasizes that energy transformations are never 100% efficient and are always accompanied by some loss of energy, predominantly in the form of heat.