chapter 12 &13 biodiversity & preserving...
TRANSCRIPT
12
Biodiversity on our planet is our greatest asset. Within this diverse collection of plants, animals, and other organisms, we have the power to provide food for a rapidly growing population, find cures for disease, and insure our economic survival.
Main
Concept
There are many
compelling reasons to
protect species.
Biodiversity benefits humans and other species
We have discovered tens of thousands of species but still have not come close to identifying or knowing all life on the planet.
Biodiversity benefits humans and other species
With diversity comes ecosystem service – Beyond providing goods, nature is a machine supporting everything we do, from providing the oxygen we need for survival to cleaning up our waste with filtering mechanisms.
Photosynthesis – Converting light energy to the chemical energy that can be stored and used by living organisms.
Nutrient cycling – Using the organic and inorganic materials from dead and decomposing organisms to support new life.
Population control – Competition and predation maintain a balance of organisms while helping maintain diversity.
Pollination – Insects, birds, mammals, and other organisms provide a mechanism for distribution of critical genetic diversity and generation of grasses, herbs, and other plants.
$44,000,000,000,000
Biodiversity benefits humans and other species
Natural spaces and nature’s services also provide cultural,
economic, and social value.
Biodiversity benefits humans and other species
Natural spaces and nature’s services also provide cultural,
economic, and social value.
Biodiversity benefits humans and other species
More biodiversity = increased ability to adapt to changing conditions
Tropical regions and rain forests around the world
hold extremely high concentrations and varieties of plants.
In addition to species and
genetic diversity, these areas have many
communities and ecosystems within a
variety of habitats and trophic levels.
Biodiversity includes genetic variation, much variety of
plant species, and many different community interactions.
Biodiversity hotspots
Some ecosystems have naturally higher species diversity. This areas often have ecological diversity– variety of habitats, niches, and ecological communities in an ecosystem.
Tropical forests (equatorial regions) tend to have high ecological and species diversity.
Endemic species– specially adapted to that locale and naturally found nowhere else on Earth.
Endemism increases with isolation, as does extinction risk
Isolated populations are especially vulnerable to detrimental environmental changes because they cannot freely breed with other populations and thereby increase their genetic diversity and chances of survival. p. 229
Main threats to biodiversity
• Habitat destruction & Fragmentation o Development o Resource
extraction (timber, minerals, fossil fuels, damns)
• Invasive species • Overexploitation • Pollution • Climate Change
Invasive species
6 groups
• Freshwater aquatic • Freshwater plant • Terrestrial plant x2 • Marine aquatic • Invertebrate
• What is it? • Where is it? • Where is it from and how did
it get here? • What problems is it causing?
• What other species or food webs is it disrupting? Etc.
• What is being done about it?
There are many different ways to protect and enhance biodiversity
Chapter 13
Preserving Biodiversity
There are many different ways to protect and enhance
biodiversity
Identifying keystone and indicator
species is an important part of that.
Conservation biology is the
science of preserving
biodiversity.
Conservation biologist
focus on protecting
individual species and
maintaining or restoring
entire ecosystems.
They must understand how
ecosystems work and their
threats.
Threats to biodiversity can lead to extinction
The rapid loss of species we are seeing today is estimated by experts to be between 1,000 and 10,000 times higher than the natural extinction rate.* These experts calculate that between 0.01 and 0.1% of all species will become extinct each year.
Extinction– end of an organism or group of organisms Extirpated– locally extinct
Low estimate of 2 million
species on planet = 200-
2,000 extinctions per
year!
High estimate of 100
million species on planet
= 10,000- 100,000
extinctions per year!
Conservation biologists designate levels of threat to species
(start at :40)
There are multiple approaches to species conservation
Single species conservation- single out well-
known animals and focus on the specific threats it
faces.
Goal- Increase population size and reintroduces
individuals to the wide.
• Captive breeding
• Field conservation
• Reintroduction programs
Ecosystem conservation- identifying entire
ecosystems-often biodiversity hotspots- that are at
risk and restoring or rehabilitating them.
Goal- return ecosystems to their original states
• Reforestation, remove non-natives
• Restore river flow
• Remediate (clean up pollution)
Benefits all species existing there
There are many different ways to protect and enhance
biodiversity
Must address the needs of
humans as well as
ecosystems and species
that are in danger.
Tradeoffs!