1. Ecology and Ecosystems

3. Ecology O2
Nutrients
CO2
Ecology is the study of relationships between living things and between living things and their environment.
Relationships involve interactions with the physical world as well as interrelationships with other species and individuals of the same species.

4. Biological Complexity
Living organisms can be studied at different levels of complexity.
From least to most complex, these levels are (in an ecological context):
Individual
Population
Community
Ecosystem
Biome
Biosphere
Biosphere
Biome
Ecosystem
Community
Population
Individual

5. The Biosphere
The biosphere is the region within which all living things are found on Earth.
It is the narrow belt around the Earth extending from the bottom of the oceans to the upper atmosphere.

6. Biomes
The biosphere encompasses all living things on Earth. It comprises a number of aquatic and terrestrial biomes.
Biomes are the largest geographically based biotic communities that can be conveniently recognized.
Biomes within the same category have specific, characteristic features.

7. Terrestrial Biomes
Terrestrial biomes are recognized for all the major climatic regions of the world and are classified on the basis of their predominant vegetation type.
The same biome may occur in widely separated regions.

8. Aquatic Biomes

9. What is an ecosystem?
An ecosystem is a system of living things that interact with each other and with the physical world.
A Biome is a collection of related ecosystems.

10. Habitat The place in which an organism lives
provides the kinds of food and shelter, the temperature, and the amount of moisture the organism needs to survive
The environment is a “global” set of conditions, both biotic and abiotic that affect an organism in it’s lifetime. An environment may contain multiple habitats

11. Communities
A community is a naturally occurring group of organisms living together as an ecological entity; the biological part of the ecosystem.
A nudibranch snail feeding on rock encrusting organisms

12. Populations
All the organisms in an ecosystem that belong to the same species

13. Individual: species
Organisms that can successfully interbreed to produce sexually viable offspring

14. Abiotic factors Abiotic = non-living Temperature Humidity
Wind & air currents
Water, water pressure & currents
Light pH
Salinity
Nutrients
Topography
Background
Shelter

15. 1. Temperature
Range
Extremes
Fluctuation
Duration
Thermoclines

16. Humidity Cooling ability Resistance to dessication Aestivation
Resistance to disease

17. Wind and Air currents Root, stem and leaf structure Flying ability
Dispersal mechanisms

18. Water, water pressure and currents
Retention (eg clay soils)
Current strength
Wave action
Depth control/pressure/resistance
Oxygenation
Food/nutrient availibility

19. Light
Intensity
Duration
Exposure
Seasonality (circadian rhythms)

20. pH
Range
Variance
Acidity/alkalinity

21. Salinity
Concentration
Thresholds
Variance
Water table/salt levels

22. Nutrients
Levels
Availibility (e.g. Nitrogen)
Variance

23. Topography
Variance
Altitude

24. Background
Fluctuation
Consistency
Textural patterns (cryptic species)

25. Shelter
Availability
Type
Conditions within