Adaptations, interdependence and competition - EdexcelAbiotic factors - data
Organisms depend on each other for survival. This is called interdependence. Both living and non-living factors will affect the abundance and distribution of organisms in a habitat.
abioticNon-living elements of an ecosystem, such as climate, temperature, water, and soil type. factors are non-living. They include light intensity, temperature and moisture levels. The abundance and distribution of living organisms in an ecosystemThe living organisms in a particular area, together with the non-living components of the environment. are affected by abiotic factors.
The effect of abiotic factors on organisms
A shingle beach has small stones instead of fine sand. Plant seeds can lodge between the small stones and start to grow, particularly at the top of the shore away from the waves. Two students set up a transect A line created, for instance, with a tape measure, along which sampling occurs. along a shingle beach. They started at the top of the beach and worked towards the sea. Every five metres they placed a quadratA square frame of known area used for sampling the abundance and distribution of slow or non-moving organisms. on the beach and measured the height of all the plants found. They found the meanThe mean is calculated by adding all of the data and dividing by the number of items of data. of this data; their results are presented in a graph below.
Question
What conclusions can you draw from this data about the mean plant height? Use numbers in your answer.
The average height of plants falls from 60 cm at the top of the shore to less than 10 cm after 25 metres. After this no plants were found.
Along with this they recorded the depth of soil (an abiotic factor) as the distance increases from the shore top.
Distance
Soil depth
0 m
16 cm
5 m
13 cm
10 m
14 cm
15 m
7 cm
20 m
5 cm
25 m
1 cm
30 m
0 cm
35 m
0 cm
40 m
0 cm
Distance
0 m
Soil depth
16 cm
Distance
5 m
Soil depth
13 cm
Distance
10 m
Soil depth
14 cm
Distance
15 m
Soil depth
7 cm
Distance
20 m
Soil depth
5 cm
Distance
25 m
Soil depth
1 cm
Distance
30 m
Soil depth
0 cm
Distance
35 m
Soil depth
0 cm
Distance
40 m
Soil depth
0 cm
Question
What conclusions can you draw from this data? Use numbers in your answer.
The soil depth decreases from 16 cm at the top of the shore to 1cm after 25 metres down it. Beyond this there was no soil.
Question
What conclusion can you draw from the number of plants and the depth of soil?
As the depth of soil decreased so did the average height of plants.