Ecology - Distribution and the Water and Carbon Cycles 200-204 Flashcards
what is the distribution of an organism
where an organism is found
what affects where an organism is found
environmental factors
what are the ways you can study the distribution of an organism
2 points
1) measure how common an organism is in two sample areas and compare them
2) study how the distribution changes across an area
what equipment is used to study the distribution of small organisms
quadrats - a square frame enclosing a known area
how can you study the distribution of small organisms
6 points
1) place a 1m^2 quadrat on the ground at a random point within the first sample area - using a random generator to pick coordinates
2) count all the organisms within the quadrat
3) repeat steps 1 and 2 as many times as you can
4) work out the mean number of organisms per quadrat within the first sample area - total number of organisms/number of quadrats
5) repeat steps 1-4 in the second sample area
6) compare the two means
how can you work out the population size of an organism on one area
2 points
1) work out the mean number of organisms per 1m^2
2) multiply the mean by the total area of the habitat
what is the population size of an organism also known as
its abundance
how can you study the distribution of organisms
3 points
1) mark out a line in the area you want to study using a tape measure (transect)
2) collect data along the line by counting all the organisms you’re interested in that touch that line
3) or collect data by using quadrats which can be placed next to each other along the line or at intervals
what can you do if its difficult to count all the individual organisms in the quadrat
2 points
1) calculate the percentage cover - e.g. if its grass
2) estimating the percentage area of the quadrat covered by a particular type of organism
how can you estimate the percentage cover of a quadrat
2 points
1) count the number of squares covered by an organism
2) make this into a percentage - divide the number of squares covered by organisms by the total number of squares in the quadrat then multiply the rest by the times it by 100
how does water availability affect the distribution of organisms
2 points
1) the distribution of some animal and plant species in the tropics changes between wet and dry seasons
2) for example each year in Africa, large numbers of giant wildebeest migrate moving north and then back south as rainfall patterns change
how does composition of atmospheric gases affect the distribution of organisms
2 points
1) the distribution of some species changes in areas where there’s more air pollution
2) for example some species of lichen can’t grow in areas where sulfur dioxide is given out by certain industrial processes
how does temperature affect the distribution of organisms
the distribution of bird species in Germany is changing because of the rise in average temperature
what causes the environmental changes
3 points
1) seasonal factors
2) geographic factors
3) human interaction - the rise in average temperature is caused by global warming
describe the water cycle
4 points
1) energy from the sun makes water evaporate from the land and sea turning it into water vapour, water also evaporates from plants called transpiration
2) the warm water vapour rises, when it gets higher up it cools and condenses to form clouds
3) water falls from the clouds as precipitation onto land where it provides fresh water for plants and animals
4) it then drains into the sea and the whole process starts again
describe the carbon cycle
8 points
1) CO2 is removed from the atmosphere by green plants and algae during photosynthesis - the carbon is used to make glucose which can be turned into carbs, fats and proteins that make up the bodies of the plants and algae
2) when plants and algae respire some carbon is returned to the atmosphere as CO2
3) when the plants and algae are eaten by animals some carbon becomes part of the fats and proteins in their bodies - then carbon moves through the food chain
4) when animals respire some carbon is returned to the atmosphere as CO2
5) when plants, algae and animals die microorganisms and detritus feeders feed on their remains - when these organisms respire CO2 is returned
6) animals also produce waste that’s broken down by detritus feeders and microorganisms
7) the combustion of wood and fossil fuels also releases CO2 back into the air
8) the carbon is constantly being cycled
draw a diagram of the carbon cycle
pg 204
