Humans in the Biosphere

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Humans in the Biosphere
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• A Changing Landscape
• A. Earth as an Island
• 1. All of the organisms that live on Earth
  share a limited resource base and depend on it
  for their long-term survival.
• 2. Humans impact the earth tremendously
• B. Human Activities
• 1. We depend on ecosystem goods and
  services.
• 2. Hunting and gathering, agriculture,
  industry and urban development all affect the
  biosphere.

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C. Hunting and Gathering 1. Hunting,
fishing, gathering 2. Some peoples still
follow the hunter-gatherer way of life to some
degree D. Agriculture 1. humans began
11,000 years ago 2. 1800s and 1900schange
in agriculture because of the invention of
machines, irrigation, new varieties of crops that
yield more
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3. monoculturegrowing the same crop year
after year on a large scale 4. Green
Revolutionincreased the worlds food
supplybegan in the 1960s 5. Challenges for
the Futureincreasing world food demands,
insects, water E. Industrial Growth and Urban
Development 1. Industrial Revolution1800s
2. Industrial development and the growth of
cities and suburbs are closely tied to the high
standard of living that so many people enjoy.
3. Concern for local and global environments
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• Renewable and Nonrenewable Resources
• A. Classifying Resources
• 1. Environmental goods and services are
  classified as either renewable or nonrenewable.
• 2. Renewable resources can regenerate or be
  replenisheddoes not mean unlimited
• a. Fresh water
• b. Trees
• 3. Nonrenewable resources cannot be
  replenished by natural processes
• a. Fossil fuels
• b. A population of trees in a forest
  ecosystem

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B. Sustainable Development 1. a way of
using natural resources without depleting them
2. Human activities can affect the quality and
supply of renewable resources C. Land
Resources 1. soil erosionthe wearing away
of surface soil by water and wind. 2.
desertificationprocess that has changed
productive land into deserts by farming,
overgrazing and drought
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D. Forest Resources 1. type of forest
determines whether or not it is a renewable
resourceold growth forests are nonrenewable
2. deforestationloss of forests E. Fishery
Resources 1. Overfishingharvesting fish
faster than they can be replaced by
reproduction 2. Sustainable
Developmentfishing regulations 3.
Aquaculturethe raising of aquatic animals for
human consumption
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F. Air Resources 1. smogmixture of smoke
and fog 2. pollutanta harmful material that
can enter the biosphere through the land, air, or
water 3. acid rainnitrogen and sulfur
compounds released into the atmosphere by burning
of fossil fuels combine with water vapor in the
air and form drops of nitric and sulfuric acids
which fall to the earth as rain G. Freshwater
Resources 1. total supply of freshwater is
limited 2. water conservation is becoming an
increasingly important aspect of sustainable
development
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• Biodiversity
• A. The Value of Biodiversity
• 1. variety
• 2. ecosystem diversityhabitats,
  communities, and ecological process in the living
  world
• 3. species diversitynumber of different
  species in the biosphere
• 4. genetic diversitythe sum total of all
  the different forms of genetic information
  carried by all organisms living on Earth today.
• 5. Biodiversity is one of Earths greatest
  natural resources

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B. Threats to Biodiversity 1. altering
habitats 2. hunting species to extinction
3. introducing toxic compounds into food
webs 4. introducing foreign species to new
environments 5. extinctionwhen a species
disappears from all or part of its range 6.
endangered speciesa species whose population is
declining so that it is in danger of
extinction C. Habitat Alteration 1.
natural habitats can be destroyed 2. habitat
fragmentationwhen development splits a habitat
into pieces
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D. Demand for Wildlife Products 1. Hunting
caused the extinction of the Carolina parakeet
and the passenger pigeon 2. meat, fur,
hides, horns E. Pollution 1. serioustoxic
compounds accumulate in the tissues of
organismsex DDT 2. biological
magnificationconcentrations of a harmful
substance increase in organisms at higher trophic
levels in a food chain or food web. F.
Introduced Species 1. invasive speciescan
reproduce rapidly because of the lack of
parasites and predators 2. sometimes drive
native species to extinction
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G. Conserving Biodiversity 1.
conservationthe wise management of natural
resources 2. Strategies for Conservation
a. Captive breeding programs b.
Focus on protecting entire ecosystems as well as
single species 3. Conservation Challenges
a. Can require people to change the way
they earn their living b. If we do not
make changes today, some resources may disappear.
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• Charting a Course for the Future
• A. Ozone Depletion
• 1. ozone layerlayer of ozone (O3) gas that
  filters out much of the suns UV radiation
• 2. Beginning in the 1970s, scientists began
  to observe a hole in the layer over the Antarctic
• 3. Since, scientists have found that the
  hole has grown and one has developed in the
  Artic, as well
• 4. CFCs have been banned because they damage
  the ozone layer
• 5. CFCs can last as long as 100 years
  current data suggests that the ozone holes should
  shrink and disappear within 50 years.

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B. Global Climate Change 1. Global
Warmingincrease in the average temperature of
the biosphere 2. Evidencecarbon dioxide in
the atmosphere have been rising for 200 years,
increasing the atmospheres natural greenhouse
effect 3. Possible Effects a. Sea
levels may rise, flooding coastal areas
b. More droughts c. New organisms may
be able to live in places where they once could
not. d. Some organisms may become
endangered or extinct because they cannot survive.
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C. The Value of a Healthy Biosphere 1.
Ecosystems are a reservoir of organisms that
might one day provide humans with new medicines
and new varieties of crops 2. People can
make wise decisions in the use and conservation
of resources a. Avoid overusing water b.
Plant trees c. Reduce, Reuse, Recycle