Biology ch 2

Principles of Ecology

V. Hassell

Everything on Earth- air, land, water, plants and animals= is connected. Understanding

these connections help us keep our environment clean, healthy and safe..

You willDescribe ecology and the work of ecologistIdentify important aspects of an organism’s environmentTrace the flow of energy and nutrients in the living and nonliving worlds

Principles of Ecology

Why is an understanding of the environment important?

They materials needed for

survival come from the

environment

It is where they find food and

shelter, reproduce and interact

with other organisms.

Organisms and their environmentObjectives

Distinguish between biotic and abiotic factors

Compare the different levels of biological

organization and living relationships

important in ecology.

Explain the difference between a niche and a

habitat

Individual organisms interact with each other and their environment

As cities expand, humans

are moving into territories

previously occupied by

fields and wildlife.

They are still in their

native area when they

turn over trashcans or get

into yards.

Natural History

The study of

plants and

animals, including

where they grow

and live, what

they eat or what

eats them

Includes Bird

Watchers

Amateur

weather

collector

EcologyUses qualitative (descriptive) and quantitative research

The study of

interactions

that take place

between

organisms and

their

environment

Uses techniques

from

Math

Chemistry,

physics, geology

Other branches

of biology

Levels of organization help scientist understand relationships.

POPULATION

A group of organisms

of the same species

which can interbreed

and live in the same

area at the same

time

Because members of the

same population compete

with each other for food,

water, mates, and other

resources.

Competition increases when

resources are in short supply

Communities-

a group of

interacting

populations of

different

species

occupying a

particular place

a pond

community

Interactions within communities

Made up of individuals of several different

populations

Located in a certain area at a certain time

A change in one population changes/affects

others.

Ex. If a fox population increases, what

happens to the rabbit population?

The

organisms in

a plant

population

and the biotic

and abiotic

factors which

impact on

them.

Ecosystem

BiosphereThe area on earth which supports life (where life is found)

Thin layer.

Supports a diverse group of

organisms in a wide range of

climates

Living things are affected by

nonliving and living factors.

Ecosystem- Factors

1. biotic

living or derived

from living

things

2.

abiotic-

nonlivin

g

factors;

sunlight

, temp.

water,

soil

If you were to study a species you would need to include:

their food

sources

Materials for

habitat

Temperature

Drought

Type of soil

Amount of

seeds

Growth

Limits of Tolerance conditions under which

growth will occur

Optimum Range- the best conditions for

growth

Limiting factors- A nutrient in short supply

which limits an organisms growth. It keeps

populations from spreading beyond areas to

which they are best adapted

Biotic factorsLife factors

All living

organisms-

regardless of

size

Are biotic

All organisms

depend on

others directly

or indirectly for

food, shelter,

reproduction or

protection.

Levels of organizationBiologist study

Individual organisms

Interactions among organisms of the same

species

Interactions among organisms of different

species

Effects of abiotic factors on interacting

species

Life Cycles

Organisms may go through

metamorphosis which means

that the young and adult

organisms do not compete for

food- eat different foods.

Biotic and Abiotic factorsForm Ecosystems

Because ecosystems include

interacting populations and the

abiotic factors, they are subject

to change

Biomes2 types of Ecosystems

Terrestrial ecosystems- on land

Include forest, measows and rotting logs

Aquatic ecosystems include fresh water and

saltwater forms

Fresh water- Includes ponds, lakes, streams

Salt water – called Marine ecosystems, make

up 70% of earth’s surface

Adaptation & change

Organisms must be able to adapt

to changing conditions.

Coastal organisms spend part of

the day underwater.

Tides affect salinity (salt content)

Organisms in EcosystemsHABITAT

Where an organism lives its life

Prairie dog-

burrows in

prairie

Birds- nest in

trees or on the

ground

Others-

Wetlands,

ponds, oceans

Food Chain- Sun is energy source

1st Producer-

AutotrophPhotosynthesi

splant

A niche

includes how it

meets its specific

needs for food,

helter, how and

where it survives

and where it

reproduces

Includes all

interactions

with biotic

and abiotic

parts of

habitat

Nichecompetition

It is an

advantage to

have a

different nich

than other

species in the

habitat

Less

competition

2 species with the

same needs can’t

exist for long

together

One will gain control

Other become

extinct, move

elsewhere or adapt

Surviving in difficult habitats

Adaptations to

survive in

different

habitats

include

Cypress knees

Polar bears

SymbiosisOrganisms living together in close,

permanent associationTypes

Mutualism- both species benefit

Commensalism- one species

benefits, the other is not affected

Parasitism- one benefits, one is

harmed

Symbiosis- Commensalism

Spanish moss

Orchids

barnacles

Symbiosis- ParasitismHarmful to one species, beneficial to another

Endoparasite

Hook worms

Do they care if

their host

dies?

Exoparasite-

outside

Tick, fleas

2.2 objectives

Compare how organisms satisfy their

nutritional needs.

Trace the path of energy and matter in

an ecosystem

Analyze how matter is cycled in the

abiotic and biotic parts of the biosphere

How organisms obtain EnergyAutotrophs

The ultimate

source of

energy is the

sun

Plants use

photosynthesis

to produce

food from light

energy.

Autotrophs

Producers

Plants

Some protist &

algae

Other organisms

depend on thes for

energy

How organisms obtain energyConsumers are Heterotrophs

Can not make

its own food

Obtain

nutrients by

eating other

organisms

Heterotrophs

Omnivore

Carnivore

Scavenger

Heterotrops- DecomposerBreakdown and release materials

Breakdown complex compounds

of dead and decaying organisms

into simpler substances

Fungi, bacteria

Flow of energy in Ecosystems Cycles of matter

Matter is composed of carbon,

nitrogen and other elements

Moves through the food chain

from producers to consumers

Food ChainsFlow of energy

Arrows indicaate direction in

which energy is transferred

May be as few as one or two – or

unlimited

Plants decomposers

Plantscowmandecomposer

(bacteria)

Food web

Shows

relationship

s for

organisms

that feed on

more than

one species

Ecological Pyramids

Only 10 % of energy is passed to next level

Flow of Energy

Food chains, food webs and ecological

pyramids are all models that show how

energy moves in only one direction

through the tropich levles of an ecosystem

Some energy lost to heat

Sunlight is souce

According to the law of

conservation of energy-

energy is neither lost or gained.

Some is transferred at each

tropic level enerters the

environment as heat, but the

total amount of energy remains

the same.

Pyramid of Biomasss

Each level in a

pyramid of

biomass

represents the

amount tht the

level above needs

to consume to

meet it’s needs

Cycles in Nature

Matter is recycled (never lost) and is not

replenished like energy from sunlgiht

There is a finite amount of

matter

The atoms that make up the

boies of organisms alive today

are the same atoms that have

been on Earth since the

beginning of time.

Water CycleEvaporation, condensation, transpiration, precipitation

The Carbon CycleLife on earth is a carbon based. Carbon is

molecule of life

Carbon dioxide + water glucose

+ oxygen

Nitrogen Cycle78 % of atm- not available

to plants

Ammonia (urine), lightning,

manure,

excess Nitrogen in waterways

can cause major algae blooms

and harm an ecosystem

causes blue baby syndrome

Phosphorus cycle

Phosphorus is essential

All organisms need phosphorusIt is Necessary for growth and development

Short cycle

Plants absorb

from soil

Eaten, animsl

dies ,

decompose

and is

returned to

soil

Long cycle

Phosphates wash

into water and

are locked in rock

Millions of years

later- rock is

exposed

Nitrogen Cycle

Everglades

Lake

Okeechobee over

flowed producing

marshy area

Development

limited water to

lake

90 % wading birds

70% other wildlife

listed as

threatened or

endangered