chapter 12 &13 biodiversity & preserving...

CHAPTER 12 &13 Biodiversity &

Preserving Biodiversity

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.


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


Natural spaces and nature’s services also provide cultural,

economic, and social value.


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)

http://en.wikipedia.org/wiki/Extinction

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


biodiversity

Must address the needs of

humans as well as

ecosystems and species

that are in danger.

Tradeoffs!


biodiversity


biodiversity

Need to consider needs of people living in the area!

• Debt for nature swaps - forgive debt in exchange for conservation

or environmental policy

• Ecotourism – supports local economies, focus on non-

consumptive use of resources

chapter 12 &13 biodiversity & preserving...

Documents