Transcript Biodiversity

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Biodiversity
Nevada Performance Standards
SEV5: Students will recognize that human
beings are part of the global ecosystem
and will evaluate the effects of human
activities and technology on ecosystems.
5a. Describe factors affecting population growth of
all organisms, including humans. Relate these to
factors affecting growth rates and carrying capacity
of the environment.
5b. Describe the effects of population growth,
demographic transitions, cultural differences,
emergent diseases, etc. on societal stability.
Essential Questions
1. List and describe
the three levels of
biodiversity on earth.
2. Describe several
ways biodiversity is
being threatened on
Earth.
3. Explain the
advantages of
protecting an entire
ecosystem instead of a
single species.
Biodiversity
•is
short for Biological diversity
•means the number of different species in a
given area.
•We have catalogued over 1.7 million different
species on earth, with most of them being
insects.
•Scientists estimate there is over 10 million
species on earth.
The Three Levels of Biodiversity
Species
Species diversity refers
to the number of
different species in an
area.
Genetic
Ecosystem diversity
refers to the variety of
habitats, communities,
and ecological
processes within and
between ecosystems.
Genetic diversity
refers to all the
different genes
contained within all
members of the
population.
Benefits of Biodiversity
• Healthy ecosystems have healthy species.
• Keystone species are species critical to the functioning of an
Connected
ecosystem.
Survival
Uses
• Genetic diversity increases the chances that some members of a
species will survive environmental changes.
• Small and isolated populations are less likely to survive such changes.
• We use organisms for food, clothing, shelter and medicine.
• Undiscovered and unstudied species are a source of potential
products.
Keystone Species
•A
keystone species is a species that is critical to
the functioning of an environment.
•An example of a keystone species is the sea
otter.
•Sea otters eat sea urchin, sea urchin eat kelp.
•The loss of the sea otter population led to the
loss of kelp beds along the US Pacific coast.
•The recovery of the sea otters led to the
recovery of the kelp populations.
Ecotourism
People value diversity for aesthetic or personal enjoyment.
Some people believe things have a right to exist whether or not
they have value. Some believe in a higher purpose.
Examples are keeping pets, camping, picking wildflowers, or
watching wildlife.
Ecotourism is a form of tourism that supports the conservation
and sustainable development of ecologically unique areas.
Origins of some foods
North America,
Central America
South America
• Corn(maize), tomato, beans (pinto, green and lima),
peanut, potato, sweet potato, avocado,
• Pumpkin, pineapple, cocoa, vanilla, pepper
Northeastern
Africa, Central
Asia, Near East
• Wheat, sesame, chick pea, fig, lentil, carrot, pea,
okra, date, walnut,
• Coffee, cow, goat, pig, sheep
India, East Asia,
Pacific Islands
• Soybean, rice, banana, coconut, lemon, lime,
orange
• Cucumber, eggplant, turnip, tea, black pepper,
chicken
Biodiversity at Risk
•65
million years ago, a series of changes in the
Earth’s climate and ecosystems caused the
extinction of about half the species on Earth,
•The extinction of many species in a relatively
short period of time is called a mass extinction.
•It takes millions of years for biodiversity to
rebound after a mass extinction.
Current Extinctions
•Scientists
are warning that we are in the midst
of another mass extinction.
•The rate of extinction is estimated to have
increased by 50x since 1800.
•Between 1900 and 2100, up to 25 percent of all
species on Earth may become extinct.
•Humans and human activity is the primary
cause of the extinction.
Cockroaches and rats have
large populations and will
not become extinct. They
adapt to many habitats
easily.
Species at risk are those that
migrate, need large or
special habitats or are
exploited by humans.
Endangered Species
A species that is likely to
become extinct if protective
measures are not taken
immediately.
Threatened Species
A species that has a
declining population and
that is likely to become
endangered if not
protected.
Habitat Destruction and
Fragmentation
Population -> more homes
and food needed
Pollution
Pesticides,
cleaning agents,
drugs and other
chemicals are
making their
way into food
webs all over
the world.
BALD EAGLE!
Florida Panthers and
Cougars
How do
humans
cause
Extinctions?
Harvesting, Hunting
and Poaching
Passenger pigeons and
bison
Invasive
Exotic
Species
A species not
native to a
particular
region.
FIRE
ANTS!!!!!
Humans Reduce Biodiversity by:
Areas of critical biodiversity
•Some
parts of the world contain a
greater diversity of species than others.
•These areas have endemic species,
meaning species that are native to and
found only within a limited area.
•Ecologists use plants as an indicator of
overall biodiversity because plants form
the basis of ecosystems on land.
•Earth’s various organisms appear to be
concentrated in certain biomes.
Tropical Rain Forests
•The
greatest loss of diversity happens in
the tropical rainforests.
•The remaining tropical rainforests only
cover about 7% of the Earth’s land
surface.
•Biologists estimate that over half of the
world’s species live in these forests.
•Unknown numbers of species are
disappearing as tropical forests are
cleared for farming and cattle grazing.
Coral Reefs and Coastal Ecosystems
•Coral
reefs occupy a small fraction of the
marine environment yet contain the majority of
the diversity there.
•Reefs provide millions of people with food and
tourism revenue.
•60% of coral reefs are threatened by
overfishing and pollution.
•Coastal areas are routes for many migrating
species as well as links to ecosystems on land.
Islands
•When
an island rises from the sea, it is
colonized by a limited number of species from
the mainland.
•Colonizing species often evolve into several
new species.
•Hawaii have 28 species of an endemic family of
birds called honeycreepers.
•Honeycreepers are endangered by competition
from exotic species.
Biodiversity Hotspots
•Hotspots
are the most threatened areas of high
species diversity.
•These are areas that have high numbers of
endemic species but are also threatened by
human activities.
•Most hotspots have lost 70% of their original
plants and include tropical rainforests, coastal
areas, and islands.
•In Madagascar, only 18% of the original forests
remain.
Biodiversity in the United States
•The
US has a wide variety of ecosystems,
including the Florida Everglades, the California
coastal region and Hawaii.
•The US holds unusually high numbers of species
of freshwater fish, mussels, snails, and crayfish.
•Land plants also have a high diversity rate with
pine trees and sunflowers.
•The California Floristic Province, a hotspot, is
home to 2,124 endemic and 565 threatened and
endangered species.
The Future of Biodiversity
Captive Breeding Programs
•Captive
breeding programs involve breeding
animals in captivity, with the hope of
reintroducing populations to their natural
habitats. Example: California Condor
Habitat loss, poaching and lead poisoning
almost killed every condor. 121 were released
into the wild but the survival is still doubtful.
Preserving Genetic Material
•One
way to save the essence of a species is by
preserving its genetic material.
•Germ plasm is any form of genetic material,
such as that contained within the reproductive
or germ cells of plants and animals.
•Germ plasm banks store germ plasm for future
use in research or species recovery efforts.
Zoos, Aquariums, Parks and Gardens
•The
original idea of zoos was to put exotic
animals on display.
•Now zoos display the few remaining members
of a species.
•They are living museums of the world’s
diversity.
Preserving Habitats and Ecosystems
•The
most effective way to save species is to
protect their habitats.
•Most of the time it takes large areas of land to
do this.
•Most conservationists now give priority to
protecting entire ecosystems rather than
individual species.
•By protecting the entire ecosystem, we may be
able to save most of the species in an
ecosystem instead of just one.
Legal Protection for Species
US Laws:
•
Are considered to be the strongest in the world.
•Endangered
Species Act, 1973. is designed to protect plant and animal
species in danger if extinction.
•As
of 2005, 1,272 species of plants and animals were listed as endangered or
threatened.
•Reintroducing
the gray wolf in certain areas of the northwestern US is in
accordance with the Act.
•It
also says anyone who harms, buys or sells any part of these species are
subject to a fine.
•Third
part prevents the government from carrying out any project that
jeopardizes a listed species.
Recovery and Habitat Conservation
Plans
•Under
the Endangered species Act the last
thing they must have is a species recovery plan
for each listed species.
•These plans often propose to protect or restore
habitat for a species.
•A habitat conservation plan – a plan that
attempts to protect one or more species across
large areas of land through trade-offs or
cooperative agreements.
•They can also have a permit to capture and
conduct research with an endangered species.
International Cooperation
•At
the global level, the International Union for
the Conservation of Nature and Natural
Resources (IUCN) facilitates efforts to protect
species and habitats.
•It is a collaboration of about 200 governmental
agencies and 700 private conservation group
from around the world.
•An international treaty, The Convention on
International Trades in Endangered Species
(CITES) was the first effective effort to stop the
slaughter of African elephants. It stopped the
sale of ivory world-wide and stopped much of
the poaching of ivory tusks.
The Biodiversity Treaty
•One
of the most ambitious efforts to tackle
environmental issues was the United Nations
Conference on Environment and Development,
also known as the Earth Summit.
•The Biodiversity Treaty was developed at this
conference.
•The treaty's goal is to preserve biodiversity and
ensure the sustainable and fair use of genetic
resources in all countries.
•The World Wildlife Fund encourages the
sustainable use of resources and supports the
wildlife protection.