Ecosystems and Material Cycles Flashcards
Define the term producer
An organism that photosynthesis.. e.g plants
Give two abiotic factors that could affect plant distribution.
Temperature, pH, pollutants, water
How do you estimate a total population using the mean number of organisms per quadrat?
Divide the field area by the quadrat size, multiply that by the mean number of daisies
Give a reason why the quadrats were placed at random
To obtain a representative sample of the field
When a preys population increases what happens to the size of the population of their predator?
It increases
What is eutrophication?
When too many nutrients are added to an ecosystem
What is desalination?
When dirty water is distilled making it potable (clean)
State two methods farmers can use to increase soil fertility
Crop rotation, fertilisers
Describe the role of nitrogen-fixing bacteria.
Live in soil / root nodules of legumes - convert atmospheric nitrogen into ammonia which forms ammonium ions
Describe one way in which carbon dioxide is removed from the atmosphere
Photosynthesis, dissolution into oceans..
