1. 11-4: Community propertiesPP

2. Species (organism) Population Community (interaction of different species) Ecosystem Biosphere

3. PROPERTIES OF A COMMUNITY
Species Richness: The number of species in an area

4. PROPERTIES OF A COMMUNITY
Species Richness: The number of species in an area
Species Evenness: the abundance of each type of species

6. Which has more species richness? Which has more species evenness?

7. BIODIVERSITY
The variety of organisms in a given area
Based on a measurement of species evenness and richness

8. BIODIVERSITY
10-30 million species with most biodiversity in insects

9. Biodiversity index A quantitative measurement of biodiversity
Ecologists can better understand community structure
Biodiversity index = # Species
# Organisms

10. Sites A, C, and D have more richness
Sites A and C has the most evenness
Which site has the highest biodiversity?

11. Calculating Biodiversity
Biodiversity index = # Species
# Organisms
The closer to 1, the healthier the ecosystem (able to withstand disturbances)

12. FORCING BIODIVERSITY
Non-native species: a species that is introduced into a community by humans
Invasive species: a non-native species that has the ability to spread quickly and cause damage to native environment
Usually has no natural predator

15. California invasive species
Fire Ant
Ice Plant
Yellow Star Thistle
Mosquito Eating Fish

16. Prevent the Spread of invasive species

17. Loss of biodiversity