6 ECOLOGY + ENVIROMENT Flashcards
Define an ecosystem
The community, and the habitat in which it lives
Define a habitat
The place/area where an organism lives
Define a population
The total number of individuals of one species in a particular habitat at a particular time
Define a community
All the populations of different organisms that live together in a habitat
What is an abiotic factor
Non-living factors which affect growth and survival of living things
What is an abiotic factor
Non-living factors which affect growth and survival of living things
What is a biotic factor
Living factors which affect growth and survival of living things
3 examples of abiotic factors
Temperature, sunlight intensity, mineral content in soil
3 examples of biotic factors
Disease, predetation, trampling
Describe how to investigate population size of an organism using quadrats
- Calculate area of habitat
- Measure individuals in one quadrat
- Place quadrat in 10 different locations using RANDOM SAMPLING
- Calculate average number of individuals in a quadrat
- Calculate how many quadrats fit into total area
- Multiple average number of individuals by how many quadrats fit into area
How to do a random sample
- Divide area into 0-10 co-ordinate grid
- Use a random number generator to get a pair of numbers
- Use them as co-ordinates to place your qudrat
Describe nitrogen fixation
Nitrogen-fixing bacteria in soil and roots of leagumes absorb nitrogen, and make it into ammonia
Describe nitrification
Ammonia is converted to nitrates by nitrifying bacteria
Explain denitrification
Nitrates are converted in nitrogen gas by denitrifying bacteria
Explain decompostion (as part of the nitrogen cycle)
Bacteria and fungi decompose dead matter by saprotrophic feeding, and ammonia is released into the soil
Explain decompostion (as part of the nitrogen cycle)
Bacteria and fungi decompose dead matter by saprotrophic feeding, and ammonia is released into the soil
Define Biodiversity
The measure of how many different species live in an ecosystem
How to measure the biodiversity of an area
- Calculate area of habitat
- Record number of each different species
- Place quadrat in 10 different locations using RANDOM SAMPLING
- Calculate average number of different species in a quadrat
- Calculate how many quadrats fit into total area
- Multiple average number of different species by how many quadrats fit into area