1. You Need to know Definition of Ecology Definition of Biosphere
Definition of Ecosystem
Definition of Habitat
Be able to list 5 types of ecosystems

2. Environmental factors affecting organisms.
Abiotic factors are non living factors
Biotic factors are living factors
Climatic factors refer to weather over a long period of time.
Edaphic factors relate to soil (soil pH, soil type, moisture, air and mineral content)

3. Abiotic Factors
Steepness
Altitude
Current
Aspect
Exposure

4. Steepness and Altitude

5. Currents

6. Biotic Factors Food Competition Predation Parasitism
Pollination and seed dispersal
Humans

7. Climatic Factors Temperature Rainfall Humidity Day Length
Light Intensity
Wind
Salinity

8. Edaphic Factors Soil pH Organic Matter Water Content Air Content
Mineral Content
Soil Type
Sand
Clay

9. Where do we get our energy from?
The sun is the primary source of energy for our planet.
Feeding allows energy to flow from one organism to another in an ecosystem.

10. Producers are organisms that carry out photosynthesis.
Consumers are organisms that take in food from another organism.
3 types of consumers
Primary consumers feed on producers
Secondary consumers feed on primary consumers
Tertiary consumers feed on secondary consumers

11. A grazing food chain is a sequence of organisms in which each one is eaten by the next member in the chain.
Grass Rabbit Fox
A food web consists of two or more interlinked food chains.
Sparrow Hawk
Badger
Blue Tit
Thrush
Caterpillar
Slug
Dock leaves

12. A pyramid of numbers represents the number of organisms at each stage in a food chain.
Fox
Rabbit
Grass

13. Niche
The ecological niche of an organism is the functional role it plays in the community.
Each bird in the pictures eats and lives in different parts of the habitat and hence do not compete with each other. They have found a niche

14. Can you describe the life of a plant?
Nutrient recycling is the way in which elements are exchanged between the living and non-living components of an ecosystem.
Elements covered in class are Carbon and Nitrogen

15. Carbon Cycle
Carbon dioxide is removed from the environment by: Photosynthesis in plants.
Carbon dioxide is returned to the environment by:
Respiration in plants, animals & micro-organisms.
Decay caused by micro-organisms.
Combustion.
Weathering.

16. CO2 Levels have increased from 0.028% to 0.036% over 200yrs
Main cause is increased combustion of fossil fuels and deforestation
Effects of Global Warming
Sea levels rise.
Weather patterns alter
Reverse direction of Gulf Stream

18. Nitrogen cycle All organisms need nitrogen for protein, DNA & RNA
80% of the air is nitrogen gas, (Brilliant I can make as much protein as I want)
However…. it is no use to living things as a gas it needs to be changed into a chemical compound called Nitrate NO3

19. Nitrogen cycle How does the Nitrogen gas change into Nitrate?
Volcanic Action
Lightning
Industrial Processes
Some Bacteria

20. Nitrogen Fixing Bacteria
N2 gas ammonia(NH3) nitrates(NO3).
These bacteria live in the soil or in the roots of clover, beans and peas (Legumes).
Plants absorb the nitrates made by the bacteria.
In return the bacteria absorbs some of the sugars made by the plant during photosynthesis.
Hence the plant and bacteria live in Symbiosis

21. Animals then eat the Plants and get their nitrogen from plant protein.
When organisms die they are decomposed by Fungi and bacteria which produce Ammonia.
Then more bacteria (called Nitrifying bacteria) change this Ammonia into Nitrate. This process is called Nitrification.
Plants can then absorb these nitrates.

22. Then there are other types of bacteria (called denitrifying bacteria) that change nitrates into nitrogen gas. This process is called Denitrification.

24. Human Impact on Ecosystems
We are going to look at 3 ways that humans affect ecosystems:
Pollution
Conservation
Waste Management

25. Pollution This is any undesirable change in the environment.
Can you name any natural pollutants?
Can you name pollution that arises from human activity?
Pollution can affect Air, Freshwater, Sea, Soil and Land.

26. Agricultural Pollution
Domestic Pollution
Industrial Pollution