2Chapter 3 Outline3-1: What is Ecology? 3-2: Energy Flow 3-3: Cycles of Matter
33-1: What is Ecology? Interactions and Interdependence Levels of OrganizationEcological Methods
4Interactions and Interdependence Ecology – the scientific study of interactions among organisms and between organisms and their environmentBiosphere – The combined portions of the planet in which all life exists.
6Levels of Organization Species – groups of organisms that can breed and produce fertile offspring.Population – group of organisms of the same species that live in the same areaCommunity – all the living organisms found in an area.Ecosystem – all the organisms that live in a place, along with their environment.Biome – group of ecosystems that have the same climate and similar dominant communities.Biosphere – the combined portions on Earth where living things are found.More Inclusive
7Ecologists study the environment in 3 ways: ObservingExperimentingModeling
83-2: Energy Flow Producers Consumers Feeding Relationships Energy From the SunEnergy Without LightConsumersFeeding RelationshipsFood ChainsFood WebsTrophic LevelsEcological Pyramids
9Producers Ecosystems need a source of energy to survive. For most ecosystems, the main source of energy is the Sun.Energy!
10Like at this deep sea vent! For a few ecosystems, it comes from chemical energy from the earth.Chemosynthesis:Carbon dioxide + hydrogen sulfide carbohydrates + sulfurEnergy!Like at this deep sea vent!
11ProducersA producer is an organism (like plants, algae or bacteria) that produces its own foodChemosynthesis – energy from inorganic chemical compounds is used to make food (some bacteria)Photosynthesis – energy from the Sun is used to make food (plants, algae, some bacteria)Producers are autotrophs because they make their own food.
12Consumer A consumer is an organism that eats another organism Another word for consumer: heterotroph
13Types of consumers(heterotrophs): Herbivores obtain energy from eating producers (autotrophs)Carnivores eat herbivores or other heterotrophs.Omnivores obtain energy from eating both autotrophs and heterotrophs.Detritovores obtain energy from eating plant and animal remains (detritus)Decomposers obtain energy from organic matter (things that were once alive).
14Energy can be tracked throughout the ecosystem through feeding relationships
15Food ChainA food chain is a series of steps in which organisms transfer energy by eating and being eaten.
16Food WebA food web is the network of complex interactions formed by the feeding relationships among the various organisms in an environment.
17Food WebEach step in a food chain or a food web is called a trophic level.https://www.etap.org/demo/biology_files/lesson6/kep29.jpg
18Food WebA food web shows all the possible feeding relationships in an ecosystem.How are food chains and food webs the same?How are they different?
19Only 10% of the energy is transferred to each trophic level.
20Energy loss can be measured in biomass of organisms.
21Energy loss and biomass comparison Energy flows one way in an ecosystem:Producers 1st Level Consumers 2nd Level Consumers 3rd Level Consumers
223-3: Cycles of Matter Recycling in the Biosphere The Water Cycle Nutrient CyclesThe Carbon CycleThe Nitrogen CycleThe Phosphorus CycleNutrient Limitation
23Recycling in the Biosphere Unlike energy, matter is recycled within and between ecosystems.Matter is passed from one organism to another and from one part of the biosphere to another through biogeochemical cycles.
24The Water Cycle Section 3-3 Condensation Precipitation Evaporation TranspirationEvaporationRunoffSeepageRootUptake
25The Water CycleWater can enter the atmosphere by evaporation and transpirationEvaporation – water changing from a liquid to a gas.Transpiration – water evaporating through tree leaves.Water cools in the air and condenses into clouds.Water falls to the ground as precipitation.Water makes its way to the ocean by runoff.
26Nutrient CyclesA nutrient is a substance an organism needs to sustain life.Some common nutrients are:Carbon (C)Nitrogen (N)Phosphorous (P)
27Carbon Important for: Co2 Released into the atmosphere by: Living tissueAnimal skeletonsPhotosynthesisCellular respirationCo2Released into the atmosphere by:Breathing, volcanoes, burning trees & fossil fuelsAbsorbed by:Oceans, Plants (esp. trees, algae),
28The Carbon CycleSection 3-3CO2 inAtmosphereCO2 in Ocean
29Nitrogen Found in the air, and in dead things and poop: Important for: N2 = nitrogen gas – 78% of the atmosphere – unable to be used by producersNH3 = ammoniaNO3- = nitrate found in dead things, able to be used by living thingsNO2- = nitriteImportant for:Making proteinsSome bacteria convert nitrogen gas into ammonia using nitrogen fixation, so producers can use them.N2 NH3Some bacteria convert nitrates back into nitrogen gas using denitrification.NO3- N2
30The Nitrogen CycleSection 3-3N2 in AtmosphereNO3-and NO2-NH3
31Phosphorous Important for: NOT found in the atmosphere Making nucleic acids (DNA, RNA)NOT found in the atmosphereMostly found in rocks and soil minerals, and in ocean sediments.
32Nutrient Limitationprimary productivity – the rate at which organic matter is created by producersWhen an ecosystem has low primary productivity because it doesn’t have enough of a single nutrient, we call that a limiting nutrient.A common limiting nutrient is phosphorous (P).