1. ECOLOGY

2. What is Ecology???
Ecology is the branch of biology that studies the interactions of organisms with one another and with their physical environment.

3. The two factors that make up the environment of an organism:
BIOTIC FACTORS
It includes all the living organisms in the environment.
ex: Producers
Consumers
Decomposers
ABIOTIC FACTORS
Light
Heat or solar energy
Water
Minerals
Soil
Oxygen
Wind etc.

4. ECOLOGICAL ORGANIZATION
Population
Community
Ecosystem
Biome
Biosphere

5. 1. POPULATION
A population is a group of individuals of the same species existing together in a given area.
Ex: *human population in Ankara
*squirrel population in ODTÜ forest
*volvox population in Eymir lake
For example, all of the Great Diving Beetle larvae and adults in the pond.

6. 2. COMMUNITY
All the populations of different organisms within agiven areamake up the community.
Ex: All of the populations in ODTÜ forest
For example, all of the numerous species of micro-organisms, plants and animals living in the pond

7. 3. ECOSYSTEM
A certain area in which organisms interact with each other and with their environment. An ecosystem includes a community and its physical environment.
Ex: ODTÜ forest
Eymir lake
The pond ecosystem includes all of the non-living components - the water, the soil surrounding the pond, the mud on the bottom, the weather and microclimate, together with the living community of organisms

8. 4. BIOME
One of the major terrestrial ecosystems, characterized by climatic and soil conditions.
Biomes are named according to the dominant plant population of them.
Tundra
Coniferous forest

9. Grassland
Savanna

10. Deciduous forest
Mediterranean
Desert

12. 5. BIOSPHERE
The portion of the earth in which living things exist.

13. HABITAT The environment of an organism; the place where it lives.
Ex: Nitrogen fixing bacteria soil
Dolphin ocean
Tapeworm human intestine

14. HABITAT

15. NICHE
The role of a species in an ecosystem. In balanced ecosystem each species occupies its own niche.
Ex: Nitrogen fixing bacteria nitrogen fixation
Pine tree ODTÜ forest photosynthesis
Saprobes in soil decompose dead material

16. Nutrition in Ecosystem
1.Autotroph:
An organism able to make all the complex organic molecules (its own food molecules) using simple inorganic compounds.
Ex: Photocynthetic bacteria
Algae
Plants
Chemosynthetic bacteria

17. Nutrition in Ecosystem
2.Heterotroph:
An organism that cannot derive energy from photosynthesis or inorganic chemicals, and so must feed on other plants or animals.
Ex: Holozoic organisms
Saprobes
Most of bacteria
Fungi

18. Nutrition in Ecosystem
A) Holozoic organisms:
Organisms take in solid organic food from ingesting other living organisms
Herbivores
Omnivores
Carnivores

19. Predator Prey Any organism that catches and kills other organisms.
Organism that is actively captured and used as food by predators.

20. Predator-Prey Relationship@

21. Nutrition in Ecosystem
Scavangers
Hyena and vultures
Crabs
Jackal

22. Nutrition in Ecosystem
B) Decomposers (Saprobes) : Fungus and bacteria

24. Food Chains and Food Webs
Food Chain: A series of organisms through which food energy is passed.
Producers, consumers and decomposers make up the food chain.
All the feeding categories that occur in an ecosystem represent different trophic levels.

25. Food Chains and Food Webs

26. Food Chains and Food Webs

27. Food Chains and Food Webs

28. Ecological Pyramids
Pyramid of numbers:

29. Ecological Pyramids

30. Ecological Pyramids Pyramid of energy: least energy 10% 10%
CARNIVORES
10%
HERBIVORES
greatest energy
PRODUCERS

31. Ecological Pyramids
Pyramid of energy:

32. Pyramid of energy:

33. Ecological Pyramids
Pyramid of energy :

34. Ecological Pyramids Pyramid of biomass: gr/m2
CARNIVORES
HERBIVORES
PRODUCERS
Because energy is lost at every step of a food chain, the biomass of primary producers tends to be greater than that of the herbivores that consume them, and herbivore biomass is greater than the biomass of the predators.

35. Ecological Pyramids Pyramid of biomass: gr/m2
Producers
Herbivores
Carnivores
Inverted pyramid of biomass in some aquatic ecosystems

36. Biological Magnification
Certain harmful substances, usually ones not found in nature but introduced by man, may get into plants and/or animals.
These poisonous substances may not be broken down in the body or excreted easily, efficiently and quickly. Instead, they accumulate in the tissues, and as the living organism eats more, the concentration of these substances increases and they pass from one trophic level to the next.  
This phenomenon is called 'Biological magnification'.

37. Biological Magnification

38. WATER CYCLE

39. 97% of the water on earth is in the oceans
Only 3% of the water on earth is freshwater
About 2.4% of the water on earth is permanently frozen in glaciers and at the polar ice caps
About 1/2 of 1 % of the water on earth is groundwater
Only about 1/100 of 1% of the water on earth is in the rivers and lakes
It takes 39,090 gallons of water to make a new car, including the tires
Over 17,000,000 houses use private wells for their drinking water supply
A person can live about a month without food, but can live only about 1 week without water

40. CARBON CYCLE

41. NITROGEN CYCLE

42. IMPORTANCE OF ECOSYSYEMS