Ecology 1: Ecosystems

Cellular Organization cells

organellesmolecules

atoms

The cell is the basic unit of life.

Levels of Organization

Organismal Level

organism

organ systems

organstissues (lowest level)

Levels of Organization

Population Level ecosystem

Community

Population

(Lowest level)

Levels of Organization

Biome

Organism Individual

Biosphere

Levels of Organization (from lowest to highest level)

• Organism= Living thing, individual• Ex. an elephant

• Population– A group of individuals in the same species, living

and interacting in one area• Ex. a herd of elephants in the Serengeti

• Community– Multiple populations interacting in one area

• Ex. grazing antelope, elephants and giraffes in the Serengeti

• Ecosystem– All populations in one area interacting with each

other and their non-living environment.• Ex. the Serengeti (all organisms plus climate, nutrients,

etc.)

Levels of Organization• Biosphere

– All areas of the earth from the ocean depths to the atmosphere that support life.

Levels of Organization

Each level of organization builds on the level below it but often demonstrates new features.

Ecological roles

• Autotrophs - Producer • makes own food (through photosynthesis or

chemosynthesis) example: plants

• Heterotrophs - Consumer • must eat other organisms for food; • primary (mouse), secondary (fox), tertiary (bobcat)

– Herbivore (eats plants) Carnivore (eats meat) Omnivore (eats both)

– Detritivore• Organisms that feed on animals remains and dead

material (crabs, earthworms)

– Decomposer• An organism (ex. fungi or bacteria) that completes the

final breakdown of materials in an ecosystem.• End of 3.1

self

other

How does energy enter the ecosystem?

– Energy hits the earth in the form of sunlight

– Autotrophs convert sunlight (or chemical) energy into organic molecules

– Less than 1% of the sun’s energy is converted into organic material

– Eventually all energy is lost back to the atmosphere as heat.

How does energy move through an ecosystem?

• Energy trapped in autotrophs (producers) then gets transferred to heterotrophs (consumers) as one organism eats another

• The easiest way to show this is by using a food chain, food web, or food pyramid.

• Food chain – series of steps in which organisms transfer energy by eating and being eaten.

How does energy move through an ecosystem?

Autotrophs

Herbivores

carnivores

omnivores

HETEROTROPHS

Food Web

Food Web: links all ecosystems in a food chain together

Food Web in a Salt marsh

This illustration of a food web shows some of the feeding relationships in a salt marsh.

What does the marsh hawk feed on?

Organisms Role in food chain

• Human _______________

• Deer _______________

• Pine tree _______________

• Bear _______________

• Rabbit _______________

• Bacteria _______________

• Mouse ________________

• Snake ________________

• Wheat ________________

• Fly maggot ________________

• Bluegrass ________________

• Hawk ________________

• Millipede ________________

• Sparrow ________________

• Cat ________________

• Frog ________________

• Algae ________________

• Trout _________________

ANSWERS:Organisms . . . . . Role in food chain

Human . . . . . CONSUMER

Deer . . . . . CONSUMERPine tree . . . . . PRODUCERBear . . . . . CONSUMERRabbit . . . . . CONSUMERBacteria . . . . . DECOMPOSER

Mouse . . . . . CONSUMERSnake . . . . . CONSUMERWheat . . . . . PRODUCERFly maggot . . . . . DECOMPOSERBluegrass . . . . . PRODUCERHawk . . . . . CONSUMERMillipede . . . . . CONSUMER

Sparrow . . . . . CONSUMER

Cat . . . . . CONSUMER

Frog . . . . . CONSUMERAlgae . . . . . PRODUCERTrout . . . . . CONSUMER

Look at the following list of organisms and identify them as either producers, consumers, or decomposer

Thinking Visually

Solar energy

Herbivore 21

3

Nutrients

Use the following words to fill in the flowchartDecomposerAutotroph or producerConsumer or carnivore

Food Web

• 1. For the food web, label each organism: (Some may have more than one label)

• P = producer

• 1 = Primary Consumer 2= Secondary Consumer 3 = Tertiary Consumer

• 2. Now label each animal as either a :

• H = herbivore

• C = carnivore

• O = omnivore

Food Pyramids

• A food pyramid is designed to show the organisms in an ecosystem, grouped by their feeding position or trophic level (1st=prod, 2nd=herbivores, etc)

• Both food chains and food pyramids show that only 10% of the energy at one trophic level makes it to the next trophic level (from the 2nd law of thermodynamics).

Energy Flow

• The figure shows energy flow in a simple food chain.

• At each level of the food chain, about 90% of the energy is lost in the form of heat.

• The total energy passed from one level to the next is only about one-tenth(10%) of the energy received from the previous organism. Therefore, as you move up the food chain, there is less energy available. Animals located at the top of the food chain need a lot more food to meet their energy needs.

Critical thinking

• Draw an energy pyramid for a five-step food chain. If 100 percent of the energy is available at the first trophic level, what is the percentage of the total energy is available at the highest trophic level

100%10%

1%0.1%

0.01%

Critical thinking

• Draw an energy pyramid for a five-step food chain. If 1,000 percent of the energy is available at the first trophic level, what is the percentage of the total energy is available at the highest trophic level

1,000%100%10%1%

0.1%

Date: December 2, 2010

Critical thinkingWrite and show your work

• Draw an energy pyramid for a four-step food chain. If 1,040 percent of the energy is available at the producer level, what is the percentage of the total energy is available at the highest trophic level.

Date: December 6, 2010

1,040%

104%

10.4%

1.04%

YOUR TURN• Draw and color a food

chains with all the organisms viewed. Be creative.

• Be sure to include arrows to show the direction of energy flow.

• Label each member of the food chain as the producer; or first, second, or third level consumer.

• Don’t forget to add the sun to your picture

• Color producers Green

• Color Herbivores Yellow

• Color carnivores Red

• Color omnivores blue

Primary Productivity

• Therefore, the ecosystems with the most productive producers have the most levels (ex. rain forest)– In most cases, there are only

3-4 levels.– End of 3.2

• The rate at which new organic material is created in an ecosystem by producers is called the Primary Productivity

• The more energy entering the food chain (from producers), the more that can pass up through the levels (only 10% moves up at each level), and as result, the more levels there can be.

How do nutrients cycle?

• Energy follows a ONE-WAY path– Sun living organisms heat atmosphere

• Matter CYCLES through living organisms endlessly

• Biogeochemical cycles– Water (hydrologic cycle)– Carbon and Oxygen– Nitrogen

Water Cycle

Rain, snow, sleet

CO2 inAtmosphere

CO2 in Ocean

Figure 3-13 The Carbon Cycle

Carbon and Oxygen Cycle

N2 in Atmosphere

NH3

NO3-

and NO2-

Figure 3-14 The Nitrogen Cycle

Nitrogen Cycle

B. Condensation

Seepage

Runoff

C. Precipitation

TranspirationA. Evaporation

RootUptake

The Water Cycle

1. Identify the stage of the water cycle that is being depicted above. Then, briefly describe the events that occur during that stage.

A._____________________________________________________B._____________________________________________________C._____________________________________________________

2. Which label represents runoff?2. Which label represents ground water?3. What is ground water?

The Water Cycle

http://www.phschool.com/webcodes10/index.cfm?fuseaction=home.gotoWebCode&wcprefix=cbp&wcsuffix=2033

Questions and Answer

1.What are the three major steps make up the water cycle?

2. What are the forms of precipitation may occur?

3. What parts of the water cycle involve absorption of energy from the sun?

4. Which part of the water releases heat back to the surrounding?

5. How do condensation and precipitation differ?

6. How evaporation and transpiration differ?

7. What happens to water that is not removed from land by evaporation?

8. Which process in living things uses carbon dioxide?

9. What is nitrogen fixation? Why is it necessary?

Niches

• Niches vs Habitats– A habitat is the location where a species

lives. • Ex. tall grassland/prairie

– A niche includes all of the species’ requirements plus its role in the ecosystem. It is determined by all the the abiotic and biotic factors relevant to the species.

• Ex. Top predator in prairie areas where gophers live, and the temperature is never below freezing.

Niche differences

• Organisms can be identified as either– Generalists

• Organisms with a broad niche• Eat lots of types of food• Live in many types of environments• Ex. house mice

– Specialists• Organisms with a narrow niche• Eat a narrow range of food items• Live in few, specific types of habitats• Ex. panda bear

Mutualism

• Mutualism occurs when both species benefit– Rhinos and oxpeckers

– trees and mycorrhizae,

– ants and acacia

– Termites and protist

– Pollination (Yucca and yucca moth)

Parasitism– one organism feeds on/lives on another

species– typically host is bigger than parasite– parasites usually do not kill host (weaken

them)– parasites need host for food, shelter, etc.– ex. fleas on dog, tapeworm in human,

mistletoe, lamprey

Commensalism

• Commensalism occurs when one species benefits, and the other neither benefits, or is harmed

• examples:– clownfish and

anemones

– epiphytes and trees

– Cattle egrets and ungulates

Predation

• Predation - one organism feeds upon the other– predator usually bigger than prey– ex. lion eating zebra

Prey Strategies

Competition

• When two species use the same resources, they are said to compete and their interaction = competition.– ex. lions and hyenas compete for food in

Africa

• Competition does not necessarily involve contact; interaction may be only by means of effects on the resources.

• No two organisms can occupy exactly the same niche at the same time

What determines where species can live?

• All species have requirements for many factors/conditions. – Abiotic factors – non-living factors; ex.

temperature, precipitation, pH– Biotic factors – other species; ex. prey

species, competing species

• For each of these factors, species exhibit a range of tolerance. – For example, a fish species may only be

found within a pH range of 4.5 to 6 in lakes.

Biomes• A major terrestrial community that is found in different areas

with similar climate is called a biome.

• Biomes are geographical areas filled with major communities, plants and animals.

• They are also known as major life zones.

• Each biome is characterized by a particular type of climate, vegetation and animals. biomes often have different types of animals and plants, or fauna and flora, which have adapted to the environment.

Biomes can be classified as

1. Terrestrial (land) Biomes which are often classified by their dominant plant life.

2. Aquatic biomes are biomes found in water and are usually named by their physical features.

• A biome’s structure and appearance are similar throughout its distribution.

The major Biomes

1. tropical rain forest

2. tropical dry forest

3. temperate woodland and shrubland (Chaparral),

4. temperate deciduous forest,

5. boreal/coniferous forest (taiga),

6. desert

7. temperate grassland

8. tropical grassland (savanna)

9. Tundra. http://www.glencoe.com/sec/science/activities/bdol/dragdrop/BDOL03.html?iRef=3&iChapter=3(drag)

Biome distribution

http://www.physicalgeography.net/fundamentals/9k.html

http://www.phschool.com/webcodes10/index.cfm?fuseaction=home.gotoWebCode&wcprefix=cbp&wcsuffix=2043

Compare/Contrast TableTen Major Biomes

Use the book to fill in the table

Biome Precipitation Temperature Soil Diversity Trees Grasses

Tropical Rain Forest

Tropical Dry Forest

Tropical Savanna

Desert

Temperate Grassland

Temperate woodland and Shrubland

Temperate Forest

Northwestern Coniferous Forest

Boreal Forest

Tundra

Compare/Contrast Table

Ten Major Biomes

Biome Precipitation Temperature Soil Diversity Trees Grasses

Tropical Rain Forest

high hot poor high dense sparse

Tropical Dry Forest variable mild rich moderate medium medium

Tropical Savanna variable mild clay moderate sparse dense

Desert low variable poor moderate sparse sparse

Temperate Grassland

moderate summer hot rich moderate absent dense

Temperate woodland and Shrubland

summer low, winter moderate

summer hot poor low medium medium

Temperate Forest moderate summer moderate, winter cold

rich high dense sparse

Northwestern Coniferous Forest

high summer mild, winter cold

rocky, acidic low dense sparse

Boreal Forest moderate summer mild, winter cool

poor, acidic moderate dense sparse

Tundra low summer mild, winter cold

poor low absent medium

Quiz: Questions and answer

1. Geographical filled with a major community of plants and animals are known as what?

2. What type of tree must lose their leaves in autumn so to prevent water lose during the frozen winters?

3. Name the biome that has nutrients rich soil and is most often use for agriculture. It is often identified as the “Breadbasket of the world?

4. What type of trees are able to keep their leaves all year and survive cold, snowy winters?

5. Why are there no trees in tundra?

6. Where does less than 1/100 of 1/10 of the Earth’s freshwater exist?

7.Name two of the five types of oceans biomes presented in this program?

Biome

Deciduous

grassland

conifers

precipitation is snow too cold

River, stream, pond and lake

Coastal waters, Near shore zone, coral reefs, open ocean, vent communities

Quiz

True/false8. In some parts of the world the chaparral is the

best represented by evergreen shrubs that are able to survive the destructive forces of floods

9. Reptiles, mammals, and huge variety of insects compete fiercely in the rain for nutrients.

10. To survive the hot time period in the desert, some animals borrow in the cold ground

F

T

T

Freshwater Habitats

• These habitats are distinct from both marine and terrestrial habitats and are very limited in area.– make up about 2% of earth’s surface– can be divided into

• Flowing water (rivers) standing water (ponds and lakes) and wetlands (seasonal coverage)

Homework (due next class)

• Homework (due next class): create a poster board of a biome. The poster board should display (but is not limited to) the following characteristics of the biome: Name of Biome, Location, Temperatures, Precipitation, Vegetation, Animals , Drawing etc.

• Or create a biome mobile.

Hanger cover with construction paper

Information in the biomes

es

Freshwater Habitats

• Estuaries– These are very important for

• Breeding grounds for fish• Filtering water

– Very productive ecosystems!– Disappearing fast (flat land near the ocean)

Ocean

• 75% of earth’s surface

• Continental shelf - shallow ocean waters - smallest area; large number of species (kelp forests)

– Intertidal zones• Along our coast

• Species can tolerate being in and out of water

• Sea stars, algae, sea anemones

– Coral Reefs• The “rain forests” of the ocean

• High diversity

• In tropical waters

Ocean

• open sea surface - contains plankton (free-floating microscopic organisms), bacteria, algae, fish larvae; responsible for 40% of world’s photosynthesis

• Benthic zone - deep sea waters - below 1000’ feet animals adapted to dark; some blind/bioluminescent

What happens when ecosystems are disturbed?

• When a disturbance impacts an ecosystem, it recovers through a process known as succession.

• Succession on newly formed habitat is called primary succession. – No remaining organisms or soil– Examples, lava flow, sand dune, glacier

retreat– It can take 1000+ years from sand dune to

forest.

Resources

• http://www.schools.utah.gov/curr/Science/sciber00/8th/energy/sciber/chains.htm (energy flow)

• http://www.schools.utah.gov/curr/Science/sciber00/8th/energy/sciber/chains.htm (food chain)

• http://glencoe.mcgraw-hill.com/sites/dl/free/0078757134/383928/BL_04.html (lab stimulation)

• http://www.vtaide.com/png/foodchains.htm

• http://www.blueplanetbiomes.org/world_biomes.htm (Biomes)

• http://www.nclark.net/CommunitiesBiomes (activities)