Transects
A transect is a line across a A place where plants, animals and micro-organisms live. or part of a habitat. It can be as simple as a string or rope placed in a line on the ground. The number of organisms of each Used in the classification of living organisms, referring to related organisms capable of interbreeding and producing fertile offspring. along a transect can be observed and recorded at regular intervals.
A transect is usually used to investigate a gradual change in a habitat rather than to simply estimate the number of organisms within it.
A kite diagram shows the number of animals (or percentage cover for plants) against distance along a transect.
In this example, the distribution of dandelion plants gradually changes from five metres to 20 metres along the transect. A A square frame of known area used for sampling the abundance and distribution of slow or non-moving organisms. has been placed at regular intervals of a metre, or a few metres, along the transect.
A gradual change in the distribution of species across a habitat is called zonation. It can happen because of a gradual change in an abiotic (non-living) factor.
Question
Using the data for the distribution of grasses in the kite diagram above, suggest how far along the transect you would find a well-used footpath.
15 m. This is where the number of grass plants is the least.
Question
When using transects to record the amount of moss found, it is impossible to count the number of plants so it is common to estimate percentage cover.
If a quadrat contains 25 sections and moss covers 16 of these sections, what percentage of the quadrat is covered in moss?
\(\frac{16}{25}\times{100}={64\%}\)
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