Ecology Chapter

3-1

Ecology

Scientific study of interactions among organisms & their interactions within the environment or

surroundings.

Levels of Organization

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Individual Population Community Ecosystem Biome Biosphere

Smallest Largest

IndividualIndividual

(Single or (Single or ONEONE member of a member of a population)population)

PopulatioPopulationn

(groups of (groups of individuals of individuals of samesame species species

living in living in samesame area) area)

Community - Community - different different populations living in a defined area.populations living in a defined area.

Ecosystem Ecosystem – – lowest level of lowest level of environmental complexity which environmental complexity which

include both the include both the bioticbiotic andand abioticabiotic factors.factors.

What are Biotic and Abiotic factors?• Biotic:Biological (living) influences

upon organisms in an ecosystem.

Ex.: Other organisms (plants, fungi, bacteria,..)

• Abiotic:Physical (nonliving) influences

upon organisms in an ecosystem.

Ex.: Climate, Soil, Water

Populations are affected by both abiotic and biotic ecological pressures.

Habitat- The area in which an organism lives

Niche:The organism’s place or ecological role it takes in the ecosystem.

No two species can share the exact same niche in a habitat!

BIOMES: Complex communities that are defined by a unique set of factors such as climate and soil.

BIOSPHERE: A part of the earth in which life exists to include land, water, air/atmosphere.

BIOMES:

* Soil: mostly Permafrost

• Dominant Plant Life - mosses, lichens, sedges and short grasses

• Dominant Animal Life – Arctic foxes, lemmings, Caribou, Shorebirds

• Climate – short, soggy summers, long, cold and dark winters.

•Location: Northern Canada, Alaska

TUNDRA:

TROPICAL RAIN FOREST

•Soil – not very rich due to dense canopy of trees and understory of shorter trees and vines.

• Dominant Plant Life – Broad-leaved evergreens, woody vines, climbing plants.

• Dominant Animal Life – Sloths, Jaguars, Anteaters, Toucans, Boa Constrictors….

•Climate – Hot and wet year round.

•Location: South America, SW Africa

DESERT:

•Soil – rich in minerals, but poor in organic matter.

•Dominant Plant Life – Cacti and other succulents.

•Dominant Animal Life – mountain lions, mule deer, bats, rats, owls, hawks…..

•Climate – low precipitation, variable temperatures

•Location – Western California, Northern Africa…

•Soil – fertile

•Dominant Plant Life – broad leaf deciduous trees (Maple, Elm), some conifers, and flowering shrubs…

• Dominant Animal Life – Deer, black bears, bobcats, squirrels….

•Climate – cold to moderate winters, warm summers, year round precipitation.

•Location: Eastern half of the US (inc. parts of Texas and Louisiana)

TEMPERATE DECIDUOUS FOREST

TAIGA OR BOREAL FOREST

Soil – acidic, nutrient poor

Plant Life – Coniferous trees (pines, spruce, fir…)

Dominant Animal Life – Lynx, Timberwolves, Moose, Beavers…..

Climate – Long, cold winters, short, mild summers, moderate precipitation

Location: Northern areas of North America (Canada), Northern parts of Eurasia

GRASSLANDS:Soil is most fertileDominant

Plant Life – lush, perennial grasses and herbs.

Dominant Animal Life – Coyotes, Badgers, Prairie Dogs, Antelopes, Llamas…

CLIMATE – Warm to hot summers, cold winters, moderate and seasonal precipitation

Location: South America, some parts of Russia and the Ukraine.

CONIFEROUS FOREST:SOIL – Acidic and Rocky

Dominant Plant Life – Douglas Firs, Redwoods, Sitka Spruce (coniferous trees).

Dominant Animal Life – Bears, Elk, Deer, Owls

Climate – mild temps., abundant precipitation during fall, winter and spring, relatively cool and dry summers.

Location: Northern North America, Northern Europe…

Ecology Ch. 3-2

Energy Flow

autotrophproducerMake their own Make their own

food fromfood fromenergy in the energy in the environment.environment.

Photosynthesis:

6CO2 + 6H2O (water) + C6H12O6 (carbohydrate) + 6O2(oxygen)

LightEnergy

heterotrophconsumerEat or consume Eat or consume

otherother organisms for organisms for

energyenergy

MANY TYPES OF HETEROTROPHS

Herbivores:• Obtain energy only

from plants

Carnivores:

•Obtain energy by eating only animals.

Omnivores:•Obtain

energy from both plants and animals.

Detritivores:•Obtain

energy from plant & animal remains, & other dead matter.

Decomposers:• Heterotrophs• Break down

organic matter• Include

bacteria & fungi

What is thedifference between

a Food Web and a

Food Chain?

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Food chain – a series of steps in an ecosystem in which organisms transfer energy by eating or being eaten.

Algae

Food Chain

Can you find all the relation-ships?

FOOD WEB: a network of interrelated food chains within an ecosystem.

Ecological Pyramids -A diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or food web.

Only 10% of the energy stored in a trophic level is passed on to the next level because the majority of the energy is used by the organism to carry out life processes such as respiration, movement and reproduction. Some of the remaining energy is released into the environment as heat.

100% energy

10% energy1% energy

ECOLOGICAL PYRAMID OF ENERGY shows relative amount of energy available to the next trophic level.

Pages 72-73

Pyramid of Numbersshows relative amount of

individual organisms at each trophic level

Pyramid of Energy

PYRAMID OF MASS:

Ecological Pyramids:

Energy Mass

Types of Symbiosis:

1. Mutualism

2. Parasitism

3. Commensalism

Symbiosis:

Describes a close relationship between 2 organisms, in which at least one of the organisms involved benefits.

Mutualism• Both organisms benefit from the relationship.

A).Clown fish is provided a protective home and the sea anemone is provided food as the clownfish lures other fish toward the sea anemone.

B). Bees receive food (nectar), while the flower’s pollen is spread for reproduction.

Parasitism• One organism benefits, and the other is

harmed (host).

A).Ticks feed on the blood of the host in which they live. The closer together organisms live, the easier these parasites can spread through the population.

B). Make up one of your own

Commensalism• One organism benefits, and the other is

neither helped nor harmed.

A). Barnacles live and grow on the bodies of various ocean organisms like whales. However, they do not help or cause any harm to them.

B). Make up one of your own.

Symbiosis

Mutualism Commensalism

Parasitism

Both species benefit from the relationship

One species benefits, but the other is neither helped or harmed

One organism lives in (or on) another and harms it

i.e.- Flowers & Bees

i.e.- Barnacles & Whales

i.e.- Tapeworms, Fleas & Tics

Aphids feed on sugary sap from the plant.

Aphids are herded and protected by the ants because the ants feed on sugary excretions the aphids produce.

-Parasitism

-Mutualism

4. PREDATION:An interaction in which one organism captures and feeds on another organism

5. COMPETITION:

Could be over a mate, food, space, water etc. Anything that would affect survival.

when organisms attempt to use an ecological resource in the same place at the same time.

Ecological Succession

Ecological Succession• The gradual replacement of an existing environment

by another.

Primary Succession: when a community develops where there was none before.

Pioneer Organisms/Species : The first species to populate an area.

Secondary Succession: when an existing community is disturbed or destroyed without removing the soil and a new community begins.

CYCLES OF MATTER

1. Water enters the atmosphere through evaporation and transpiration.

2, Water vapor cools and condenses to form clouds.

3. The cloud cools and droplets fall back to earth in the form of some type of precipitation.

Precipitation: snow, rain, sleet, hail, etc.

4. Some rain water runs right back into the lake. The rest seeps into the ground.

5. This underground water collects and flows back to the lake. The cycle begins again..

Water Cycle: process by which water moves from ocean and land into the atmosphere and back.

Condensation

The Carbon Cycle: a process through which the element carbon cycles through the environment.

1. In photosynthesis, producers remove CO2 gas from the atmosphere to make organic molecules (sugars)

2. Animals get organic molecules from plants & return CO2 gas to the atmosphere through respiration.

3. When plants and animals die in an ecosystem, CO2 gas is returned to the atmosphere during decomposition.

4. Fossil fuels (Coal, oil, natural gas which were once living organic material) when burned produce CO2 gas and this is returned to the atmosphere and increases the amount of CO2 gas in the air.

Draw this in your notes.

The Nitrogen Cycle: a process through which the element Nitrogen is changed into a useable form and recycled back into the atmosphere.

1. Producers (plants) absorb these forms through their roots.

2. Nitrogen fixation: actions by some bacteria & lightning change N2 gas into ammonia (NH4

+) and nitrate ions (NO3

-).

3. Consumers (herbivores) obtain nitrogen from the plants they eat.

4. Decomposers break down animal waste, dead animals, & dead plant material & return the nitrogen to the soil.

5. Other bacteria return nitrogen in the soil back to the atmosphere (denitrification)

Draw this in your notes.

Populations

Chapter 5

Three Characteristics of a Population

1. Geographic Distribution – describes an area inhabited by a population

2. Density : # of individuals per unit area

3. Growth Rate : rate at which population changes in size

POPULATION ECOLOGY: The study of how the population sizes of species living together in groups change over time and space.

Factors that affect Size of a Population

1.Birth Rate - number of organisms born each year.

2.Death Rate – number of organisms that die yearly.

3. Immigration – People moving into an area

4.Emigration – People moving out of an area

Limits to a Population

• 1. Carrying Capacity: the number of organisms that an environment can support.

• 2. Limiting Factors: something that could cause a population growth to decrease. There are 2 types of limiting factors – Density-Dependent and Density-Independent.

Density-dependent Factors (affect larger populations)

1.Competition

2.Predation

3.Parasitism

4.Disease brought on not only by bacteria but also by stress, overcrowding etc.

(ex: Indian tigers fighting over land as it becomes less available, causes stress and they won’t mate)

Density-Independent Factors

1.Unusual Weather (drought, freeze)

2.Natural Disasters (Tsunami, Earthquake, Forest Fires, Floods)

3.Seasonal Cycles (Hurricanes)

4.Human Activities (deforestation, pollution, over-hunting, industrial growth, urban dev.)

Renewable & Non-Renewable Resources

• Non-Renewable: can’t be replenished

Ex: fossil fuels such as coal, oil and

natural gas

Renewable: can be regenerated or replenished but not necessarily unlimited.

Ex: trees, water

Biodiversity

The variety of organisms in the biosphere

Has provided us with a variety of foods, industrial products and medicines inc. painkillers, antibiotics, heart medications, antidepressants and anticancer drugs.

Threats to the Biodiversity can lead to species becoming endangered even extinct.

Examples of threats are altering habitats, overhunting, introduction toxic compounds into food webs and introduction of foreign species to new environments.

BIOLOGICAL MAGNIFICATIONA PROCESS IN WHICH THE CONCENTRATIONS OF A HARMFUL SUBSTANCE (TOXINS, POLLUTANTS ETC.) INCREASE AS THEY MOVE THROUGH THE TROPHIC LEVELS.