Presentation on theme: "Ecology The study of interactions that take place between organisms and their environment."— Presentation transcript:
1EcologyThe study of interactions that take place between organisms and their environment.
2Chapter 2 Principles of Ecology Sections 1 and 2Organisms and Their EnvironmentNutrition and Energy Flow
3What is the biosphere? Portion of Earth which supports living things. Includes both abiotic and biotic factors.
4What are abiotic factors? The nonliving parts of an organism’s environment.Air currents, temperature, moisture, light, soil
5What are biotic factors? All living organisms which inhabit an environment.
6Levels of Organization OrganismPopulationBiological CommunityEcosystemBiosphere
7Interactions within Populations Group of organisms of the same species which interbreed and live in the same area at the same time.Some organisms form adaptations to decrease the amount of competition within the population.
8Interactions Within Communities Biological CommunityMade up of interacting populations in a certain area at a certain time.A change in one population in a community may cause changes in the other populations.
9EcosystemMade up of interacting populations in a biological community and the community’s abiotic factors.Two major types of ecosystemsTerrestrial – located on landAquatic – locate in both fresh- and saltwater
10What is a habitat? The place where an organism lives out its life. Nichethe role or position a species has in its environmentHow an organisms meets its needs for food and shelter, how and where it reproduces and survives.May change over the life of the organism.
11SymbiosisA close and permanent association between organisms of different species.3 TypesMutualismCommensalismParasitism
12MutualismBoth species benefit from the relationship
13CommensalismOne species benefits and the other species is neither harmed nor benefited.
14ParasitismHarmful to one species yet benefits the other.
15How do organisms obtain energy? Producers – AutotrophsOrganism that use light energy or energy stored in chemical compounds to make energy-rich compounds.Example: Plants use sunlight to make energy during the process of photosynthesis.
16How do organisms obtain energy? Consumers – HeterotrophsOrganisms which cannot make their own food and so have to feed on other organisms.Five main types of consumers.
19OmnivoresHeterotrophs that eat both plants and animals.
20ScavengersHeterotrophs which eat animals which have already died.
21DecomposersBreak down the complex compounds of dead and decaying plants and animals into simpler molecules which can be more easily absorbed.
22How Do We Chart the Flow of Matter and Energy in an Ecosystem? Food Chain – A model which shows one way in which matter and energy move through an ecosystem.Arrows indicate the direction of energy transfer.Each time energy is transferred, part of the energy is given off as heat.
23Each organism in a food chain represents a feeding step, or trophic level, in the passage of energy and materials.First order heterotroph – Feeds on plantsSecond order heterotroph – feeds on a first order heterotroph
24Food WebShows all possible feeding relationships at each trophic level in a community.
25Ecological PyramidAnother way to show the flow of matter and energy in an ecosystem.Pyramid of NumbersPyramid of Energy(Energy decreases at each trophic level in the pyramid through uneaten organisms and heat given off to the environment.)Pyramid of Biomass(Biomass is the total weight of living matter at each trophic level.)
26MatterThe biosphere contains a fixed amount of water, carbon, nitrogen, oxygen, and other materials required for life.These materials are cycled through the biosphere and used by many different organisms.
27Water CycleA model that describes how water moves from the surface of the earth to the atmosphere and back to the surface again.
28Water Cycle Components of the water cycle: Evaporation Transpiration Occurs when liquid water turns into water vapor (gas).TranspirationOccurs when plants release water into the air.RespirationReleases water vapor to the air.Animal WastesReturns water to the environment.CondensationOccurs when water vapor changes to a liquid.CloudsWhen water vapor cools, it condenses on tiny particles of matter (like dust) in the air and forms tiny droplets.PrecipitationEventually the “cloud” droplets become so heavy that they fall to the earth as precipitation.
29Carbon CycleDuring photosynthesis, autotrophs use energy from the sun to convert carbon dioxide into energy rich carbon molecules.The carbon is transferred to heterotrophs through the food chain.Carbon is returned to the atmosphere as a waste in the form of carbon dioxide.Very slow process.
30Nitrogen CyclePlants cannot use nitrogen directly from the air...so, bacteria in the soil convert the nitrogen from the air into compounds that plants can use.Animals get the nitrogen they need by eating plants.Nitrogen is returned to the environment through animal wastes and dead and decaying organisms.
31Phosphorous Cycle Short-term Cycle: Long-term Cycle Plants obtain phosphorous from the soil.Animals get the phosphorous by eating the plants.Phosphorous is returned to the soil through decomposing dead organisms.Long-term CyclePhosphates that are washed into water become trapped in rocks as insoluble compounds.As the rock erodes over millions of years, the phosphorous is released back into the environment.