Biodiversity, Succession and Biodiversity, Succession and ResourcesResources

BIODIVERSITYBIODIVERSITY

• Degree to Degree to which species which species VARYVARY within within an ecosysteman ecosystem

• Which of these Which of these has more has more biodiversity?biodiversity?

WHY IS BIODIVERSITY SO WHY IS BIODIVERSITY SO IMPORTANT?IMPORTANT?

• The Back-up plan:The Back-up plan:• ““Backup” orgs if one species dies due Backup” orgs if one species dies due

to disease, there is one to fill the nicheto disease, there is one to fill the niche• Maintains stable ecosystemMaintains stable ecosystem::

• If lots of orgs, every niche can be filled! If lots of orgs, every niche can be filled! Therefore, stable ecosystem!Therefore, stable ecosystem!

• Benefits Humans!:Benefits Humans!:• Ensures a variety of genetic materialEnsures a variety of genetic material• Vast rainforests may hold cures, Vast rainforests may hold cures,

medicines and other useful resources!medicines and other useful resources!

HOW DO HUMANS HOW DO HUMANS REDUCEREDUCE BIODIVERSITY?BIODIVERSITY?1.1. DEFORESTATION:DEFORESTATION:

• Destruction of forestsDestruction of forests• IMPACTIMPACT: Forces many orgs to find new homes: Forces many orgs to find new homes

• If cannot adapt, will become extinctIf cannot adapt, will become extinct

2.2. OVER HUNTING:OVER HUNTING:• When bounties offered for a certain species, it can When bounties offered for a certain species, it can

become over hunted become over hunted • EXEX: LION: LION

• IMPACTIMPACT: With such a drastic drop, will affect : With such a drastic drop, will affect pop’ns of other animals pop’ns of other animals

• EXEX: DEER POP’N ROSE B/C NO LIONS; DEER : DEER POP’N ROSE B/C NO LIONS; DEER OVERGRAZED AND STARVED THEMSELVESOVERGRAZED AND STARVED THEMSELVES

HOW DO HUMANS REDUCE HOW DO HUMANS REDUCE BIODIVERSITY?BIODIVERSITY?

3.3. Clearing land for farming and space:Clearing land for farming and space:• Replacing a diverse ecosystem with one or Replacing a diverse ecosystem with one or

two crops two crops • IMPACTIMPACT: Taking away resources for : Taking away resources for

ourselves and other speciesourselves and other species

4.4. DIRECT HARVESTING:DIRECT HARVESTING:• Taking species out of natural habitat for our Taking species out of natural habitat for our

benefit (wanting unusual pets or plants)benefit (wanting unusual pets or plants)• IMPACT:IMPACT: We are reducing the # of those We are reducing the # of those

species in their natural habitatspecies in their natural habitat

HOW DO HUMANS REDUCE HOW DO HUMANS REDUCE BIODIVERSITY?BIODIVERSITY?

5.5. IMPORTED SPECIES :IMPORTED SPECIES :• When a species is imported and released When a species is imported and released

into a new environmentinto a new environment• IMPACT: IMPACT: New species may adapt well and New species may adapt well and

drive out existing species drive out existing species • EX: Rabbits in AustraliaEX: Rabbits in Australia

• IMPACT: IMPACT: New species often become pests New species often become pests because they have NO NATURAL because they have NO NATURAL PREDATORSPREDATORS

• EX: Zebra mussels in NY waterwaysEX: Zebra mussels in NY waterways

Stages of SuccessionStages of Succession

What is Ecological Succession?What is Ecological Succession?• A series of changes by which one A series of changes by which one

habitat naturally changes into anotherhabitat naturally changes into another

• PROCESS:PROCESS:• Starts with simple habitat w/ little diversityStarts with simple habitat w/ little diversity• CLIMAX COMMUNITY:CLIMAX COMMUNITY:

• A stable diverse habitat (ex. Forest)A stable diverse habitat (ex. Forest)• Will be reached if climate remains stable over a Will be reached if climate remains stable over a

number of yearsnumber of years

When does Succession occur?When does Succession occur?1.1. When environment becomes suitable for When environment becomes suitable for

another community:another community:• Grasses grow in shallow soil, but add Grasses grow in shallow soil, but add

nutrients as they live and dienutrients as they live and die• Soil then becomes suitable for shrubsSoil then becomes suitable for shrubs• Shrubs shade out the grasses and take Shrubs shade out the grasses and take

overover• Over time, shrubs will be shaded out by Over time, shrubs will be shaded out by

treestrees2.2. When natural disasters occur that alter stable When natural disasters occur that alter stable

ecosystemsecosystems• Fires, overgrazing, etc…….Fires, overgrazing, etc…….• Altered ecosystems will need many Altered ecosystems will need many

successions to recoversuccessions to recover

Stage 1: Bare BedrockStage 1: Bare Bedrock

BareBedrock

Stage 2: Lichens growStage 2: Lichens grow

BareBedrock

Bedrock With

Lichens

Stage 3: Mosses growStage 3: Mosses grow

BareBedrock

Bedrock With

Lichens

BedrockWith

Mosses

Stage 4: Grasses growStage 4: Grasses grow

BareBedrock

Bedrock With

Lichens

BedrockWith

Mosses

Grasses

Stage 5: Shrubs and small treesStage 5: Shrubs and small trees

BareBedrock

Bedrock With

Lichens

BedrockWith

Mosses

Grasses

Trees And

Shrubs

Stage 6: Climax Forest (100 – 200 Stage 6: Climax Forest (100 – 200 years without disturbance)years without disturbance)

BareBedrock

Bedrock With

Lichens

BedrockWith

Mosses

Grasses

Trees And

Shrubs

ClimaxForest

Succession can also happen in a Succession can also happen in a lake!lake!

LakeHabitat

Erosion causes

buildup ofOrganic debris in

lake

Lake fills in becoming shallower

and eventually becomes a

swamp

Filling in continues

and eventually a climax

forest results

What resources can we use over What resources can we use over and over again?and over again?• RENEWABLE RESOURCESRENEWABLE RESOURCES• Can be replaced naturallyCan be replaced naturally• Still need to be used carefullyStill need to be used carefully

• EXEX: : Fish are renewable but over harvesting Fish are renewable but over harvesting and damaging env. can inhibit renewaland damaging env. can inhibit renewal

• Can you name some renewable Can you name some renewable resources?resources?• Water, food, solar energy, fruits/vegs, Wood, Water, food, solar energy, fruits/vegs, Wood,

BambooBamboo

What resources do we use that What resources do we use that cannot be replaced?cannot be replaced?

• NONRENEWABLE RESOURCESNONRENEWABLE RESOURCES• Decisions we make today affect what our future Decisions we make today affect what our future

will havewill have• Most things we use are being depleted due to Most things we use are being depleted due to

industrialization and technologyindustrialization and technology• Can you list some nonrenewable resources?Can you list some nonrenewable resources?

• Fossil fuels (coal, oil, natural gas), mineralsFossil fuels (coal, oil, natural gas), minerals• PRESERVATION =PRESERVATION = The 3 R’s The 3 R’s

REDUCEREDUCEREUSEREUSE

RECYCLE – RECYCLE – Brain Pop Video