Download Ch 2-3 Human Actions

CHAPTER 2
HUMAN ACTIONS
Section 3
Meeting Ecological Challenges
Notes 2-3
Ecological Footprints
• What is our impact on the biosphere?
• Ecological Footprint:
• Total area of the land and water ecosystems that
provide the resources that each person uses
• Includes: energy, food, water, shelter, resources needed
to absorb wastes (sewage and greenhouse gases)
• Can be used to determine the carrying capacity for
humans
• Hard to calculate a footprint but we can compare
• USA person uses 4x as many resources as the worldwide
average
• USA uses 2x as many resources as England
Ecological Footprints
• Three things can give us a sustainable future
• Recognize the problem
• Find the cause
• Change the behavior
• First Problem Example
• Ozone layer
• Protects us from UV rays
• Second Problem Example
• Fisheries
• Third Problem Example
• Climate Change
Biodiversity
• Biodiversity: total of all genetically based variation
in all organisms in the biosphere
• Ecosystem diversity: different kinds of ecosystems that
exist
• Habitats, communities and ecological processes
• Species diversity: number of different species in an area
• 1.8 million species have been found and studied
• 30 million estimated to still be unknown
• Genetic diversity: all the different forms of genetic
information carried by one species or by all organisms
• If an organism loses genetic diversity, it is less likely to be able to
survive changes in its environment
Value to Biodiversity
• Medicine:
• Most medicines are found in nature
• When we lose biodiversity, we lose genetic info that may carry
useful medicine
• Agriculture:
• Wild plants may carry genes for disease resistance and pest
resistance
• If we lose biodiversity, we lose those genes
• Healthy Ecosystems:
• Keystone species: the one species that can collapse an entire
ecosystem if it is removed
• When ecosystems are gone, soil, water and air quality will be poor
Threats to Biodiversity
• Habitat Fragmentation:
• Breaking habitats up into little pieces
• Competition for food, space and other resources is high
• Organisms are forced to leave or die
• Demand for Wildlife Products
• Over-hunting: killing animals and causing them to become
endangered
• Hunted for meat, hides or skins, sold as pets
• Introduction of Species
• Exotic species can out compete native species
• This makes it invasive
• Native species can die off
Threats to Biodiversity
• Pollution:
• DDT: dichlorodiphenyltrichloroethane
• http://www.nbcnews.com/nightly-news/video/ddtpesticide-exposure-linked-to-breast-cancer469123651811
• Acid Rain
• CO2 makes oceans more acidic
• Climate Change:
• Affects temperature, rainfall and other factors
• Species must adapt quickly to changing climates or risk
dying
Conserving Biodiversity
• Protecting Individual Species:
• Captive breeding programs
• Trying to increase genetic diversity and then return species to the wild
• Ex: panda
• http://video.nationalgeographic.com.au/video/exploreorg/giant-panda-
reserve-eorg
• Preserving Habitats and Ecosystems
• Setting aside areas for parks and reserves
• Biologists and ecologist work to find hotspots to make sure the
correct places are being saved
• Considering Local Interested
• Working on changing habits
• Recycling, driving hybrids, using solar panels, etc.