Ecology
Subdecks (4)
Cards (30)
- Decomposition - the breakdown of a dead organism into simpler substances
- Decomposition carried out by:
- detritus feeders (detritivores) - small animals eg worms
- Decomposers - microorganisms eg bacteria
- Factors that affect the rate of decomposition:
- Oxygen availability
- Temperature
- Water content
- Compost - used to fertilise and improve the soil
- Biogas generators - large containers in which animal or plant waste is left to decay anaerobically
- Peat - a type of soil that is formed from decaying vegetation, especially peat moss
- Land uses:
- building
- farming
- quarrying
- dumping waste
- Problems of deforestation:
- no photosynthesis
- burning forests
- reduces biodiversity
- Peat bogs often drained for:
- fuel
- farmland
- habitat destruction reduces biodiversity
- Quadrats - to measure abundance
- Transects - to measure how distribution changes
- food security - to have to enough food to live a healthy life
- Factors affecting food security:
- Rising populations
- New pests and pathogens
- Diets change as countries become wealthier
- Environmental changes due to climate change
- Fuels, pesticides, fertilizers, animal feed
- Conflicts
- Greenhouse effect diagramA) ReflectedB) EscapesC) Absorbed
- How waste damages the environment:
- Water : Sewage , farming
- Land : Landfill , nuclear waste
- Air : Factory , fossil fuels
- Maintaining biodiversity:
- Breeding programmes
- Reduce farming
- Rules and regulations
- How we increase global food production:
- Clearing of forests and other natural lands for agriculture
- Application of fertilisers, pesticides and herbicides
- Selective breeding
- Genetic modification
- Genetically modified organisms (GMO) - involves the addition of a helpful gene
- Example of helpful bacteria is ' Bt toxin ' which produced the toxin, making them resistant to insect pests
- Example of a GM crop is 'Golden Rice' it produces vitamin A.Lack of vitamin A can cause blindness.