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Pre-class

1) Read and highlight the handout (would have been yesterday’s notes)

2) Compare and contrast CLAYS and SANDS1) Include these phrases“pore size” and “Surface area to volume ratio”

3) Have your binder out for POP QUIZ BINDER CHECK! ☺☺☺☺

3-3 What Are the Major Components of an Ecosystem?

� Concept 3-3A Ecosystems contain living (biotic) and nonliving (abiotic) components.

� Concept 3-3B Some organisms produce the nutrients they need, others get their nutrients by consuming other organisms, and some recycle nutrients back to producers by decomposing the wastes and remains of organisms.

Ecosystems Have Living and Nonliving Components

� Abiotic• Water• Air• Nutrients• Rocks, sand, soil, clay, gravel…• Heat• Solar energy

� Biotic• Living and once living

Major Biotic and Abiotic Components of an Ecosystem

Fig. 3-9, p. 57

Decomposers

Precipitation Oxygen (O 2)

Carbon dioxide (CO 2)

Producer

Primaryconsumer(rabbit)

Secondaryconsumer(fox)

Producers

Water

Soluble mineralnutrients

Range of Tolerance for a Population of Organisms

INSERT FIGURE 3-10 HERE

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Fig. 3-10, p. 58

Feworganisms

Feworganisms

Noorganisms

Noorganisms

Lower limitof tolerance

Higher limitof tolerance

Abundance of organisms

Zone ofintolerance

Zone ofphysiological

stress

Optimum range

Temperature

Zone ofintolerance

Zone ofphysiological

stress

Low High

Pop

ulat

ion

size

Several Abiotic Factors Can Limit Population Growth

� Limiting factor principle• Too much or too little of any abiotic

factor can limit or prevent growth of a population, even if all other factors are at or near the optimal range of tolerance

Producers and Consumers Are the Living Components of Ecosystems (1)

� Producers, autotrophs• Photosynthesis• Chemosynthesis

� Consumers, heterotrophs• Primary• Secondary• Third and higher level

� Decomposers

Producers and Consumers Are the Living Components of Ecosystems (1)

� Producers, autotrophs• Photosynthesis – store sun’s energy in

chemical bonds • Plants, algae

• Chemosynthesis – store energy from a natural gradients (temperature or chemical) into chemical bonds

• Ex: Strange organisms deep in the ocean by hydrothermal vents

Consumers

� Consumers, heterotrophs• Primary – eat producers

• Ex: Caterpillar, rabbit, grasshoppers• “Herbivores”

• Secondary – eat primary consumers• Ex: Blue Jay (bird), • “Carnivores” or “omnivores”

• Third and higher level• Ex: Hawk (Bird of prey)

Consumers, continued

� Decomposers• Primarily bacteria and fungi• Return nutrients from dead plants and

animals back into the soil for producers to re-use

• They can secrete enzymes that speed up the break-down of bodies of dead organisms into nutrient compounds (water, CO2, minerals, etc…)

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Consumers, continued

� Detritivores• “Detritus feeders” eat the waste or dead

bodies of other organisms (“detritus”)• Ex: Mites, earthworms, catfish, some insects,

and vultures (“scavengers”)

Detritivores and Decomposers on a Log

Fig. 3-11, p. 60

Mushroom

Detritus feeders Decomposers

Long-hornedbeetle holes

Time progression Powder broken down bydecomposers into plantnutrients in soil

Bark beetleengraving

Carpenterant galleries Termite and

carpenterant work Dry rot

fungus

Woodreducedto powder

Two types of cellular respiration

� Aerobic respiration• Metabolic process that uses O 2 to break

glucose down into CO 2 and H2O

� Anaerobic respiration, fermentation• Metabolic processes in the absence of O 2

• Can produce ethanol, methane, acetic acid, hydrogen sulfide…instead of CO 2 and H2O

• These are the “stinky” processes!

Exit Ticket

� Make a simple food web for YOURSELF today – are you an omnivore, a carnivore or an herbivore?

Pre-class

1) Turn in HW2) Complete WS

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Label each trophic level

12/3: Ecosystems, Continued

Chapter 3

3-1 What Is Ecology?

� Concept 3-1 Ecology is the study of how organisms interact with one another and with their physical environment of matter and energy.

Species Make Up the Encyclopedia of Life

� Species

� 1.75 Million species identified

� Insects make up most of the known species

� Perhaps 10–14 million species not yet identified

Some Levels of Organization of Matter in Nature Ecologists Study Connections in Nature

� Ecology

� Levels of organization• Population

• Genetic diversity• Community• Ecosystem• Biosphere

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Fig. 3-3, p. 52

Parts of the earth's air, water, and soil where life is found

Biosphere

Smallest unit of a chemical element that exhibits its chemical properties

Ecosystem

Community

Population

Organism

A community of different species interacting with one another and with theirnonliving environment of matter and energy

Populations of different species living in a particular place, and potentially interacting with each other

A group of individuals of the same species living in a particular place

Cell

An individual living being

The fundamental structural and functional unit of life

Molecule

Atom

Chemical combination of two or more atoms of the same or different elements

3-2 What Keeps Us and Other Organisms Alive?

� Concept 3-2 Life is sustained by the flow of energy from the sun through the biosphere, the cycling of nutrients within the biosphere, and gravity.

The Earth’s Life-Support System Has Four Major Components

� Atmosphere• Troposphere

• Stratosphere

� Hydrosphere

� Geosphere

� Biosphere

Fig. 3-6, p. 55

Rock

AtmosphereVegetationand animals

Lithosphere

Biosphere

Mantle

Crust

Soil

Biosphere(living organisms)

Geosphere(crust, mantle, core)

Mantle

Core

Hydrosphere(water)

Crust(soil and rock)

Atmosphere(air)

Three Factors Sustain Life on Earth

� One-way flow of high-quality energy beginning with the sun

� Cycling of matter or nutrients

� Gravity

Fig. 3-12, p. 60

Heat

HeatHeat

Decomposers(bacteria, fungi)

Abiotic chemicals(carbon dioxide,

oxygen, nitrogen,minerals)

Solarenergy

Consumers(herbivores,carnivores)

Producers(plants)

Heat Heat

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3-4 What Happens to Energy in an Ecosystem?

� Concept 3-4A Energy flows through ecosystems in food chains and webs.

� Concept 3-4B As energy flows through ecosystems in food chains and webs, the amount of chemical energy available to organisms at each succeeding feeding level decreases.

Energy Flows Through Ecosystems in Food Chains and Food Webs

� Food chain

� Food web

A Food Chain

Fig. 3-13, p. 62

Heat Heat

Heat

Heat Heat

Heat

Heat

Solarenergy

Tertiaryconsumers

(top carnivores)

First TrophicLevel

Second TrophicLevel

Third TrophicLevel

Fourth TrophicLevel

Producers(plants)

Primaryconsumers(herbivores)

Secondaryconsumers(carnivores)

Decomposers and detritus feeders

Pyramid of Energy Flow3-5 What Happens to Matter in an Ecosystem?

� Concept 3-5 Matter, in the form of nutrients, cycles within and among ecosystems and the biosphere, and human activities are altering these chemical cycles.

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Nutrients Cycle in the Biosphere

� Biogeochemical cycles, nutrient cycles• Hydrologic

• Carbon• Nitrogen• Phosphorus• Sulfur

� Connect past, present , and future forms of life

Water Cycles through the Biosphere

� Natural renewal of water quality: three major processes• Evaporation• Precipitation• Transpiration

� Alteration of the hydrologic cycle by humans• Withdrawal of large amounts of freshwater at

rates faster than nature can replace it• Clearing vegetation• Increased flooding when wetlands are drained

Hydrologic Cycle Including Harmful Impacts of Human Activities

Fig. 3-17, p. 66

Transpirationfrom plants

Evaporationfrom land

Precipitationto land

Precipitationto ocean

Evaporationfrom ocean

Condensation Condensation

Infiltrationand percolationinto aquifer

Surfacerunoff

Surface runoffRunoff

Globalwarming

Reduced recharge ofaquifers and floodingfrom covering land withcrops and buildings

Aquiferdepletion fromoverpumping

Increasedfloodingfrom wetlanddestruction

Pointsourcepollution

Groundwatermovement (slow)

Lakes andreservoirs

Ice andsnow

Ocean

Processes

Processes affected by humans

Reservoir

Pathway affected by humans

Natural pathway

Science Focus: Water’s Unique Properties

� Properties of water due to hydrogen bondsbetween water molecules:• Exists as a liquid over a large range of

temperature• Changes temperature slowly• High boiling point: 100˚C• Adhesion and cohesion

• Expands as it freezes • Solvent• Filters out harmful UV

Carbon Cycle Depends on Photosynthesis and Respiration

� Link between photosynthesis in producers and respiration in producers, consumers, and decomposers

� Additional CO2 added to the atmosphere• Tree clearing• Burning of fossil fuels

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Natural Capital: Carbon Cycle with Major Harmful Impacts of Human Activities

Fig. 3-18, p. 68

Pathway affected by humans

Diffusion

Transportation

Deforestation

Respiration

Respiration

Decomposition

Forest fires

Compaction

Burningfossil fuels

Photosynthesis

Animals(consumers)

Plants(producers)

Marine food websProducers, consumers,decomposers

Carbonin plants

(producers)

Carbonin fossil fuels

Carbon dioxidedissolved in ocean

Carbonin limestone ordolomite sediments

Carbonin animals

(consumers)

Processes

Reservoir

Natural pathway

Carbon dioxidein atmosphere

Nitrogen Cycles through the Biosphere: Bacteria in Action (1)

� Nitrogen fixed• Lightning

• Nitrogen-fixing bacteria

� Nitrification

� Denitrification

Nitrogen Cycles through the Biosphere: Bacteria in Action (2)

� Human intervention in the nitrogen cycle• Additional NO and N2O

• Destruction of forest, grasslands, and wetlands• Add excess nitrates to bodies of water• Remove nitrogen from topsoil

Nitrogen Cycle in a Terrestrial Ecosystem with Major Harmful Human Impacts

Fig. 3-19, p. 69

Decomposition

Nitrogenloss to deepocean sediments

Processes

Reservoir

Pathway affected by humans

Natural pathway

Nitrogenin atmosphere

Nitrogenin oceansediments Ammonia

in soil

Nitratein soil

Nitrogenin plants

(producers)

Nitrogenin animals

(consumers)Volcanicactivity

ElectricalstormsNitrogen oxides

from burning fueland using inorganicfertilizers

Nitratesfrom fertilizer

runoff anddecomposition

Nitrificationby bacteria

Denitrificationby bacteria

Uptake by plants

Bacteria

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Annual Increase in Atmospheric N 2 Due to Human Activities

Fig. 3-20, p. 70

Projectedhumaninput

Total human input

Fertilizer andindustrial use

Nitrogen fixationin agroecosystemsFossil fuels

Year

2050200019801960194019201900

0

50

100

150

200

250

300

Nitr

ogen

inpu

t (t

erag

ram

s pe

r ye

ar)

Phosphorus Cycles through the Biosphere

� Cycles through water, the earth’s crust, and living organisms

� May be limiting factor for plant growth

� Impact of human activities• Clearing forests• Removing large amounts of phosphate from the

earth to make fertilizers

Phosphorus Cycle with Major Harmful Human Impacts

Fig. 3-21, p. 71

Processes

Reservoir

Pathway affected by humans

Natural pathway

Phosphatesin mining waste

Phosphatesin sewage

Animals(consumers)

Bacteria

Plants(producers)

Phosphatesin fertilizer

Phosphatedissolved inwater

Phosphatein shallowocean sediments

Phosphatein deep oceansediments

Oceanfood webs

Phosphatein rock(fossil bones,guano)

Seabirds

Platetectonics

Erosion

Runoff

Runoff Runoff

Sulfur Cycles through the Biosphere

� Sulfur found in organisms, ocean sediments, soil, rocks, and fossil fuels

� SO2 in the atmosphere

� H2SO4 and SO4-

� Human activities affect the sulfur cycle• Burn sulfur-containing coal and oil• Refine sulfur-containing petroleum

• Convert sulfur-containing metallic mineral ores

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Natural Capital: Sulfur Cycle with Major Harmful Impacts of Human Activities

Fig. 3-22, p. 72

Processes

Reservoir

Pathway affected by humans

Natural pathway

Dimethylsulfide

a bacteriabyproduct

Sulfurin oceansediments

Sulfurin soil, rock

and fossil fuels

Sulfurin plants

(producers)

Sulfurin animals

(consumers)

Sulfur dioxidein atmosphere

DecayDecay

Uptakeby plants

Mining andextraction

Sulfuric acidand Sulfate

deposited asacid rain

Smelting Burningcoal

Refiningfossil fuels