ecosystems and material cycles Flashcards
what is parasitism?
where a species benefits at the expense of another species
what is mutualism?
where a species benefits and provides for another species
how would you use a quadrant to estimate the number of flowers in a 10m x 10m field?
- divide the field into 100 1m x 1m squares
- get a random number generator to pick a number
- take the quadrant and place it in the square
- count the number of flowers in the square
- repeat with different squares 5 times and find an average
- multiply by 100 to find the average number of flowers on the field
how do you calculate the efficiency of biomass transfers?
efficiency of biomass transfers= biomass transferred to the next level/ biomass on previous level x 100
what are 3 positives and negatives to human interactions with ecosystems?
positives:
- raise awareness to the public
- afforestation and can regrow destroyed things
- stop humans from doing certain things that damage the environment
negatives:
- release greenhouse gases to the atmosphere
- deforestation to build things on it
- overfishing
what is food security?
having enough food to feed the population
what are 3 factors that affect food security?
- increase birth rate
- conflict in some countries
- climate change
what is the process of the carbon cycle?
co2 is removed from the air through photosynthesis and these plants are eaten by animals, when they die, they decompose and the carbon is released into the atmosphere again through burning fossil fuels
what is compost and what does it do?
the decaying of biological material, used by farmers as natural fertilisers
what conditions are needed for decay
more oxygen available for aerobic respiration which produces heat, the higher the temperature the higher the rate of decay so compost is made quicker
what is the water cycle?
suns energy causes water to evaporate from the seas to make water vapour which is also formed from transpiration, water vapour rises, cools, condenses to form clouds then it precipitates on land and sea and the process repeats
what is nitrogen often used for?
included in fertilisers to form ammonium nitrate to stimulate growth
how can we tell if water is polluted?
the presence of bloodworms and sludgeworms
how do we know if water is clean?
the presence of freshwater shrimps and stonefly
how do we know if an area is less polluted?
rose blackspot fungus
lichen