a changing landscape--how humans have impacted ecosystems how have we changed the landscape? what...

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A Changing Landscape--How humans have

impacted ecosystems

A Changing Landscape--How humans have

impacted ecosystems

How have we changed the landscape?

What are the consequences of these changes?

How have we changed the landscape?

What are the consequences of these changes?

What was the Green Revolution?

What was the Green Revolution?

1950s--> Increase food production HOW? 1) New, highly productive varieties of

crops (High yield wheat & corn) 2) Monoculture--Growing the same

crop 3) Chemical pesticides & fertilizers 4) Heavy equipment

1950s--> Increase food production HOW? 1) New, highly productive varieties of

crops (High yield wheat & corn) 2) Monoculture--Growing the same

crop 3) Chemical pesticides & fertilizers 4) Heavy equipment

Industrial and Agricultural Chemicals

Industrial and Agricultural Chemicals

High concentrations can cause serious problems for wildlife and humans. Widespread DDT use in the 1950s threatened fish-eating birds like pelicans, osprey, falcons, and bald eagles. It caused females to lay eggs with thin, fragile shells, reducing hatching rates and causing a drop in birth populations. Since DDT was banned in the 1970s, bird populations are recovering.

Still a concern is mercury, which accumulates in the bodies of certain marine fish such as tuna and swordfish.

High concentrations can cause serious problems for wildlife and humans. Widespread DDT use in the 1950s threatened fish-eating birds like pelicans, osprey, falcons, and bald eagles. It caused females to lay eggs with thin, fragile shells, reducing hatching rates and causing a drop in birth populations. Since DDT was banned in the 1970s, bird populations are recovering.

Still a concern is mercury, which accumulates in the bodies of certain marine fish such as tuna and swordfish.

In the highest trophic levels, pollutant concentrations may reach 10 million times

their original concentration in the environment.

In the highest trophic levels, pollutant concentrations may reach 10 million times

their original concentration in the environment.

Biological MagnificationBiological Magnification

EutrophicationEutrophication

excessive nutrients in a lake or other body of water, usually caused by runoff of nutrients (animal waste, fertilizers, sewage) from the land ...

excessive nutrients in a lake or other body of water, usually caused by runoff of nutrients (animal waste, fertilizers, sewage) from the land ...

Stages of Lake SuccessionStages of Lake Succession

Ozone Layer ThinningOzone Layer Thinning

The Ozone HoleThe Ozone Hole

Biodiversity--TypesBiodiversity--Types

Species Diversity--The variety of species within a community

Genetic Diversity-- the genetic variability within a species.

Ecosystem Diversity-- the organization of species in an area into distinctive plant and animal communities.

Species Diversity--The variety of species within a community

Genetic Diversity-- the genetic variability within a species.

Ecosystem Diversity-- the organization of species in an area into distinctive plant and animal communities.

THREATS TO BIODIVERSITYTHREATS TO

BIODIVERSITY

Services of an Ecosystem(What an Ecosystem does for

us)

Services of an Ecosystem(What an Ecosystem does for

us) Solar Energy Production of oxygen Storage & Recycling nutrients Regulation of climate Purification--H2O & Air Storage of fresh H2O Food Production Nursery habitats for wildlife Detox. waste Natural Pest & Disease control

Solar Energy Production of oxygen Storage & Recycling nutrients Regulation of climate Purification--H2O & Air Storage of fresh H2O Food Production Nursery habitats for wildlife Detox. waste Natural Pest & Disease control

HEAVY METALS Why are they harmful?

HEAVY METALS Why are they harmful?

Lead (Pb) Mercury (Hg) Cadmium (Cd)

All interfere with normal nervous system function(s)

Note--Some heavy metals are important in our diet--Fe (iron) Ca (calcium)

Lead (Pb) Mercury (Hg) Cadmium (Cd)

All interfere with normal nervous system function(s)

Note--Some heavy metals are important in our diet--Fe (iron) Ca (calcium)

BIODIVERSITY HOT SPOTSBIODIVERSITY HOT SPOTS

CONSERVING BIODIVERSITYCONSERVING BIODIVERSITY

Identify & Protect habitat

HOW?

National Parks & wildlife refuges

Captive breeding programs

Identify & Protect habitat

HOW?

National Parks & wildlife refuges

Captive breeding programs

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