Transcript Humans and Biodiversity Powerpoint

Unit 3 Chapter 5.3, 6.1, 6.3
Human Population Growth
Humans and the Biosphere
Biodiversity
5.3 Human Population Growth
Human population tends to increase dramatically over
time.
Exponential
Human pop. growth
is mainly due to:
•Nutrition
•Sanitation
•Medicine
•Health care
World Population Growth
 Growth rate reached peak about
1962-1963
 The human population is still
growing in size but the growth
rate is slowing down.
Patterns of Human Population
Growth
Demography- examines characteristics of
human populations and attempts to explain how
those populations will change over time.
Birth rates, death rates, and the age structure of a
population will help predict why some countries
have high growth rates while other countries
grow more slowly.
6.1 Humans and the Biosphere
Humans affect regional and global environments
through agriculture, development, and industry in
ways that have an impact on the quality of Earth’s
natural resources, including soil, water, and
atmosphere.
Agriculture- a dependable supply of food can be
stored for later use. Enabled humans to gather and
settle in cities and towns.
Monoculture- enables efficient sowing, tending,
and harvesting of crops using machines. (example,
soy beans)
Development: As many more people choose to
live in cities and suburbs, these areas produces
more and more wastes and they can affect air,
water, and soil resources.
Industrial Growth: Industrial growth due to
building of homes, clothes, electronics, require a
lot of energy to produce and to power. Many
industries produce waste directly into air, water,
and soil.
Sustainable Development
Ecosystem goods and services (clean air and water) are often
not free. If there is no natural resource towns must spend
money to mechanically or chemically treat the water.
Renewable resources- can be replaced or produced by a
healthy ecosystem (a tree that is cut down, then a new one is
replanted.
Nonrenewable resources- cannot be replenished within a
reasonable amount of time. (fossil fuels like coal, oil, and natural
gas)
Sustainable development – provides for human needs while
preserving the ecosystems that produce natural resources.
Approved April 19, 2011, the Cape Wind
Project will build 130 wind turbines that will
supply the cape and the islands with ¾ of it’s
energy needs.
6.3
Biodiversity- is the total of all genetically
based variation in all organisms in the
biosphere.
Ecosystem diversity- the variety of
habitats, communities, and ecological
processes in the biosphere.
Species diversity- the number of
different species in the biosphere or in a
given area.
Genetic Diversity- the sum of all the
different forms of genetic information
carried by a particular species, or by all
organisms on Earth.
Why is the genetic
diversity of a
species important
to its survival?
Biodiversity Video
~8:27
Benefits of biodiversity
Wild species are the original sources of many
medicines. Many drugs come from plants and other
living things.
Genetic biodiversity is important in agriculture. The
genes of wild plants can be used to breed or genetically
engineer new plants that can become very useful
crops.
The number and variety of certain species (keystone
species) maintain an ecosystem’s stability, productivity
and value to humans.
Example: Honey bee video
Threats to Biodiversity
•Altered habitats for development or farming
•Hunting and demand for wildlife (exotic pets)
•Introduced species (invasive species)
•Pollution: DDT, pesticides, acid rain, excess
carbon dioxide
•Climate change
Conserving Biodiversity
Protecting individual species: Scientists trap
and selectively breed to maximize genetic
diversity, then reintroduce into the
environment (panda bear)
Preserving Habitats and Ecosystems:
Sanctuaries, parks, protected areas all
preserve habitats.
Considering local interests: Incentives for
buying solar panels or carbon credits for
companies.