ECOLOGYChapter 3

WHAT IS ECOLOGY?Section 3-1

ECOLOGYEcology is the study of organisms and their interaction with the environment.

An organism is any living thingExamples: Humans, animals, plant, bacteria

ECOLOGYThe BiosphereThe biosphere is the combined portions of the planet where life exists, including land, air, water, or atmosphere.

It extends from about 8 kilometers above the earths atmosphere to about 11 kilometers below the surface of the water

LEVELS OF ORGANIZATIONTo understand the relationships within the biosphere, ecologists ask questions about events and organisms that range in complexity from a single individual to the entire populationINDIVIDUALPOPULATIONCOMMUNITYECOSYSTEMBIOMEBIOSPHERE

IMPORTANT VOCABULERY-Species (individual) group of similar organisms can breed and produce fertile offspring-Populations- group of individuals of same species that live in the same area-Communities- group of populations that live together in a defined area-Ecosystem- collection of all organisms in a particular place includes nonliving or physical environment-Biome- group of ecosystems that have the same climate and similar dominate communities

-Biosphere- all portions of living planet

THINK OF A MNMOMIC TO REMEMBER THE LEVELSB B E C P S

WHATA YOUR MNMONIC?B B E C P S Bad Boys Escapes Community Prison Suddenly

BIOLOGICAL METHODSRegardless of the tools they use, scientists conduct modern ecological research using three basic approaches1. Observing-What species live here?-How many species?2. Experimenting-test hypotheses-set up experiment in lab or field3. Modeling-make models -predictions-test further with observations and experiments

ENERGY FLOWSection 3-2

P R O D U C E R SThe sun is the main source of energy for life on earthHOWEVER, there are some organisms that rely on other sources of energy These organisms use energy stored in inorganic (bonds that do not contain carbon) chemical compoundsA good example of these types of organisms are those found deep in the ocean near thermal ventsThe organisms use the chemical energy that is loaded in the water surrounding the vent

AUTOTROPHSA groups of organisms that can use the energy in sunlight to convert water and carbon dioxide into Glucose (food)Autotrophs are also called Producers because they produce all of the food that heterotrophs useWithout autotrophs, there would be no life on this planetEx. Plants, Algae, and certain Bacteria

AUTOTROPHS

BREAK DOWN THE WORDAuto - SELFTroph - FOOD

AUTOTROPHSChemotrophsAutotrophs that get their energy from inorganic substances, such as saltLive deep down in the ocean where there is no sunlightEx. Bacteria and Deep Sea Worms

HOW DO THEY MAKE THEIR OWN FOOD?PHOTO lightSYNTHESIS to makeHarness solar energy to produce foodWhere?On land ---plants main autotrophsIn water --- upper layers of waterCHEMO chemicalSYNTHESIS to makeHarness chemical energy to produce food with the absence of lightWhere?On land mainly bacteria in hot springsIn water deep ocean floor volcanic ventsPHOTOSYNTHESISCHEMOSYNTHESIS

CONSUMERSMany organisms cannot make their own food. The ONLY way to obtain energy is from other organisms.these organisms are called consumers or heterotrophsDefinition- organisms that rely on other organisms for their energy and food supplyHETERO otherTROPH - food

HETEROTROPHS

THERE ARE DIFFERENT SUB-TYPES OF CONSUMERSHerbivoresOmnivoresCarnivoresDetritivoresDecomposers

DIFFERENT SUB-TYPES OF CONSUMERSConsumers/heterotrophs1. Scavengers/Detritivores feed on the tissue of dead organisms (both plans and animals)DETRITIUS- dead matter VORES to consumeEx. Vultures, Crows, and Shrimp

SUB-TYPES OF CONSUMERSConsumers/heterotrophs2. Herbivores eat ONLY plantsHERBI a plant VORE to consumeEx. Cows, Elephants, Giraffes

SUB-TYPES OF CONSUMERSConsumers/heterotrophs3. Carnivores eat ONLY meatCARNI MEAT VORE to consumeEx. Lions, Tigers, Sharks

SUB-TYPES OF CONSUMERSConsumers/heterotrophs4. Omnivores eat BOTH plants and animals OMNI all vore- to consumeEx. Bears and Humans

FEEDING RELATIONSHIPSEnergy flows through an ecosystem in one direction from the sun to producers then to consumers

TRANSFER OF ENERGYWhen a zebra eats the grass, it does not obtain all of the energy the grass has (much of it is not eaten)

When a lion eats a zebra, it does not get all of the energy from the zebra (much of it is lost as heat)

TRANSFER OF ENERGYThe two (2) previous examples of energy transfer show that no organism EVER receives all of the energy from the organism they just ate

Only 10% of the energy from one trophic level is transferred to the next this is called the 10% law

TROPHIC LEVELSEnergy moves from one organisms to another when it is eaten

Each step in this transfer of energy is know as a trophic levelThe main trophic levels are producers, consumers, and decomposers

FOOD CHAINSThe energy flow from one trophic level to the other is know as a food chainA food chain is simple and directIt involves one organism at each trophic levelPrimary Consumers eat autotrophs (producers)Secondary Consumers eat the primary consumersTertiary Consumers eat the secondary consumersDecomposers bacteria and fungi that break down dead organisms and recycle the material back into the environment

FOOD CHAIN

FOOD WEBMost organisms eat more the JUST one organism

When more organism are involved it is know as a FOOD WEB

Food webs are more complex and involve lots of organisms

FOOD WEB

FOOD WEB

ECOLOGICAL PYRAMIDSDiagram that shows the relative amount of energy or matter contained within each trophic level in a food chain or food web

ECOLOGICAL PYRAMIDAn ecological pyramid shows the relationship between consumers and producers at different trophic levels in an ecosystem (see diagram to right)

The Pyramid shows which level has the most energy and the highest number of organisms

Three Main Types of Ecological PyramidsENERGYBIOMASSNUMBERS

ENERGY PYRAMIDOnly about 10% of the energy available within one trophic level is transferred to organisms at the next trophic level

Ecological Pyramid of Energy

ECOLOGICAL PYRAMID of ENERGY

Pyramid of BIOMASSThe total mass of the organic matter (living matter) at each trophic level is called biomass

Biomass is usually expressed in grams per unit area

Biomass is just another term for potential energy energy that is to be eaten and used.

BIOMASS PYRAMID

Pyramid of Numbers

Pyramid of Numbers

ECOLOGICAL PYRAMIDWhich level has the most energy?Which level has the most organisms?Which level has the least organisms?Which level has the least energy?

CYCLES OF MATTERSection 3-3

CYCLES OF ENERGYUnlike the one way flow of energy, matter is recycled within and in between ecosystems

WATER CYCLEOrganisms need water for metabolism (all chemical reactions) Water is necessary for photosynthesisPlants absorb water into their rootsAnimals drink water or consume it in their food

Evaporation water changes into gasTranspiration water evaporation from leaves

STEPS OF THE WATER CYCLE1. Water evaporates from lakes, rivers, oceans, etc..2. Plants give off water in a process called transpiration3. Water condenses in the atmosphere and falls back to earth in the form of precipitation4. The water runs off back into lakes, rivers, etc.5. The cycle repeats

STEPS OF THE WATER CYCLEWays to return water to the environment 1. respiration2. excretion (animal wastes)3.transpiration (plants)4. precipitation

CARBON CYCLECarbon is found in the environment as carbon dioxideCarbon dioxide is needed for photosynthesisCarbon dioxide is returned to the environment in 3 ways1. respiration2. decomposition 3. the burning of fossil fuels.

NITROGEN CYCLEThe atmosphere is 78% nitrogen, 21% oxygen, 1% other gases

We can't use nitrogen in the air we breath - it must come from the foods we eat.

NITROGEN CYCLENitrogen compounds are important for 3 major reasons in humans:1. Proteins- are necessary for muscle development and certain chemical reactions (blood clotting)2. Enzymes and hormones - control chemical reactions in your body - digestion, reproduction etc.3. Nucleic Acids - carry the traits from one generation to the next

NITROGEN CYCLENitrogen compounds are placed back in food chains 2 major ways:1. Decomposers

2. Nitrogen-fixing bacteria- bacteria on the roots of certain plants (legumes - peas, beans) take nitrogen from the air and put it in the soil

PHOSPHORUS CYCLEessential to living organisms because it forms part of life sustaining molecules, such as DNA and RNAWhere is P found?not very common in biospheremostly land, rocks, soilas rocks wear down, p is releasedused by marine animals

NUTRIENT CYCLESPrimary productivity- rate which organic matter is created by producersWhat is the factor that controls primary productivity?limiting nutrient when ecosystem is limited by single nutrient that is scare or cycles very slowlyFarmers aware of this and use fertilizers with nitrogen, phosphate and potassiumrun-off causes nutrient poor oceans to get lots of nutrientalgal bloom- disrupts ecosystem

THE END

***************************************************