Humans Impact

1
Humans Impact

• Human Changes To Landscape

2
A Changing Landscape

• Hawaii
• Polynesians Arrive 400 a.d.
• Eco Friendly But They Brought
• Pigs
• 60 species Native Birds Extinct When Cook arrived
  in 1778
• Europeans Bring
• Ranching, Rats, Mongoose, Disease

3
Hawaii Today

• Gone, Extinct
• 2/3 of the Native Birds
• Hundreds of Native species
• Land Snails
• Plants
• Insects
• Non-Native species Introduced

4
Earth as an Island

• All organisms on Earth share a limited resource
  base.
• Human population is still growing
• The planet resources are fixed, finite. They
  can not be increased.

5
To Understand Earths Systems

• Remember Apply What You Have Learned About
• Energy Flow
• Resource Cycles
• Climate
• Population Dynamics

6
Human Activities

• Industry Technology Are Human Tools That Give
  Us A Tremendous Advantage
• If used wisely
• Our Activities Change Ecosystems In Ways We Dont
  Expect
• Rats Mongooses - Killer Bees
• Kudzu - Rabbits

7
Human Activities

• Key Concept
• Among the human activities that have transformed
  the biosphere are
• Hunting Gathering
• Agriculture
• Agrarian
• Horticultural
• Industry
• Urban Development

8
Hunting Gathering

• Primary Means of Survival
• Small Groups, usually nomadic
• After Humans Arrived In North America Large
  species disappeared
• Mammoths
• Ground Sloths
• Saber Toothed Cats

9
Agriculture

• Began after the last Ice Age 11,000 yrs.
• Nomads settled into villages
• Dependable Food Supply
• Governments Social Planning Began

10
Agriculture

• Domestication of Animals
• Expanded Food Supply
• Provided Energy To Do Work
• Overgrazing Endangered Soils
• Strained Clean Water Supplies

11
Agriculture

• From Traditional To Modern Agriculture
• 1450-1700 European Exploration
• Expanded Food Supply
• Corn, Potato, Tomatoes
• 1800s Technology Advancements
• Large Scale Irrigation
• Farm Machinery

12
New Foods For Europe
13
Agriculture

• Efficiency Increase Resulted In
• Overgrazing Endangered Soils
• Strained Clean Water Supplies

14
Traditional Farming
15
The Green Revolution

• By The 1950s, The World Population Is Straining
  Food Supply
• Global Effort to Improve Food Production Begins
• Intensive Farming Practices
• New Strains of Crops Developed
• Vastly Improved Harvest/Yield

16
Green Revolution

• Monoculture Developed
• Miracle Strains of Crops
• Large Fields of Single Crops Planted
• Irrigation
• Heavy Fertilizer Use
• Pesticides
• Same Crop Planted Year after Year
• Food Production More Than Doubled

17
Irrigation
18
Fertilization
19
Pesticides
20
Monoculture
21
Green Revolution

• But The Green Revolution Cause Problems
• Depleted Water Supplies
• Pesticides Fertilizers alkalized soils
• Created Super-Pests
• Altered Ecosystems

22
Green Revolution

• Advantages Enormous
• Vastly Increase Food Production
• Especially Heavily Populated Countries
• Global Food Production Doubled
• Mexico, Yield Increases 10 Fold

23
Industrial Growth/Urban Dev.

• Requires Energy Fossil Fuels
• Requires Space Urban Sprawl
• Requires Space Habitat Destruction
• Produces Wastes Pollution
• Concentrates Population Cities
• Alters Ecology

24
Ecological Footprint

• Amount of land necessary to produce and maintain
  enough food, water, shelter, energy and waste for
  each person in an area.