3 EcosystemA community of different species interacting together & with the chemical & physical factors making up its non-living environment.
4 Nonliving and Living Components of Ecosystems Ecosystems consist of nonliving (abiotic) and living (biotic) components.Figure 3-10
5 Biosphere Ecosystems Realm of ecology Communities Populations UniverseGalaxiesBiosphereSolar systemsPlanetsEarthBiosphereEcosystemsEcosystemsCommunitiesPopulationsRealm of ecologyOrganismsCommunitiesOrgan systemsOrgansFigure 3.2Natural capital: levels of organization of matter in nature. Ecology focuses on five of these levels.TissuesCellsPopulationsProtoplasmMoleculesAtomsOrganismsSubatomic ParticlesFig. 3-2, p. 51
6 PopulationA group of individual organisms of the same species living w/in a particular area.
7 CommunityThe population of all species living & interacting in an area.
8 HabitatThe place where an organism or a population lives.
10 Niche The total way of life or role of a species in an ecosystem. All the physical, chemical, and biological conditions a species needs to live & reproduce in an ecosystem.
11 Niche: an individual’s ecological role Fundamental niche = when an individual fulfills its entire role by using all the available resourcesRealized niche = the portion of the fundamental niche that is actually filledDue to competition or other species’ interactions
12 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.HerbivoresPrimary consumers that eat producersCarnivoresPrimary consumers eat primary consumersThird and higher level consumers: carnivores that eat carnivores.OmnivoresFeed on both plant and animals.
13 Energy passes through trophic levels One of the most important species interactions is who eats whomMatter and energy move through the communityTrophic levels = rank in the feeding hierarchyProducersConsumersDetritivores and Decomposers13
14 ProducersAn organism that uses solar energy (green plant) or chemical energy (some bacteria) to manufacture its food.
15 Producers: Basic Source of All Food PhotosynthesisProducers: Basic Source of All FoodThe process in which glucose is synthesized by plants.Most producers capture sunlight to produce carbohydrates by photosynthesis:
16 ProductivityThe amount of increase in organic matter per unit of time.
17 Primary Consumer (herbivore) An organism that feeds directly on all or parts of plants.
18 Secondary Consumer (carnivore) An organisms that feeds only on primary consumers. Most are animals, but some are plants (Venus fly-trap).
19 Tertiary Consumer (carnivore) Animals that feed on animal-eating animals. Ex. hawks, lions, bass, and sharks.
20 Quaternary Consumer (carnivore) An animal that feeds on tertiary consumers. Ex. humans.
21 Decomposer (scavenger, detritivore) An organism that digests parts of dead organisms, cast-off fragments, and wastes of living organisms. Ex. bacteria and fungi.
22 DecompositionAs plant or animal matter dies it will break down and return the chemicals back to the soil.This happens very quickly in tropical rainforest which results in low-nutrient soils.Grasslands have the deepest and most nutrient rich of all soils
23 Decomposers and Detrivores Decomposers: Recycle nutrients in ecosystems.Detrivores: Insects or other scavengers that feed on wastes or dead bodies.Figure 3-13
25 Abiotic chemicals (carbon dioxide, Heat oxygen, nitrogen, Solar Heat minerals)HeatSolarenergyHeatHeatProducers(plants)Decomposers(bacteria, fungi)Figure 3.14Natural capital: the main structural components of an ecosystem (energy, chemicals, and organisms). Matter recycling and the flow of energy—first from the sun, then through organisms, and finally into the environment as low-quality heat—links these components.Consumers(herbivores,carnivores)HeatHeatFig. 3-14, p. 61
27 Biomass The organic matter produced by plants; dry weight. Energy from wood, garbage & agricultural waste.Can be used for electrical energy!
28 StructureShows the decrease in usable energy available at each succeeding trophic level in a food chain or web.
29 Relationship Between Biomass and Energy Biomass is dry weight & represents the chemical energy stored at each energy level.Water is neither a source of energy, nor has any nutritional value.
30 10% RuleWe assume that 90% of the energy at each energy level is lost because the organism uses the energy. (heat)It is more efficient to eat lower on the energy pyramid. You get more out of it!This is why top predators are few in number & vulnerable to extinction.
31 Food webs show relationships and energy flow Food chain = the relationship of how energy is transferred up the trophic levelsFood web = a visual map of feeding relationships and energy flowIncludes many different organisms at all the various levelsGreatly simplified; leaves out the majority of species31
32 Food Webs/ChainsPurpose – determines how energy & nutrients move from one organism to another through the ecosystemArrows – point from the producer to the consumer
34 (decomposers and detritus feeders) First TrophicLevelSecond TrophicLevelThird TrophicLevelFourth TrophicLevelProducers(plants)Primary consumers(herbivores)Secondary consumers(carnivores)Tertiary consumers(top carnivores)HeatHeatHeatSolar energyHeatHeatFigure 3.17Natural capital: a food chain. The arrows show how chemical energy in food flows through various trophic levels in energy transfers; most of the energy is degraded to heat, in accordance with the second law of thermodynamics.HeatHeatDetritivores(decomposers and detritus feeders)HeatFig. 3-17, p. 64
36 Trophic LevelsEach step in the transfer of energy through a food chain or food web is known as a trophic level.A trophic level is one of the steps in a food chain or food pyramid; examples include producers and primary, secondary, and tertiary consumers.
39 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.
40 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.Figure 3-19
41 Question of the Day Explain why ecological efficiency only 10%? 90% of available energy is lost at heat or other waste energy as it passes through each trophic level. As a result the amount of energy decreases as it moves up and food web/chain.