Question

Describe two (2) techniques required to study ecosystems then provide an example of each technique. Suggest two (2) advantages and (2) disadvantages for each of your chosen techniques.

Answer 1

Answer. The 2 techniques used to study the ecosystem are:

• Quadrat method to study the frequency of species in an area.
• Quadrat method to study the density of species in an area.

A quadrat is a square area generally of 1 X 1 metre. This is made artificially by metre scale, using nails and tying ropes along the nails.

Quadrat method is used for studying the density and frequency of an ecosystem. It can be illustrated with the help of an example:

For simplicity a quadrat is subdivided into 50cm X 50cm quadrats as seen in the figure. Plant species of 5 types are taken at a time and then reading is taken as shown in the table:

Plants of 5 types are identified and the same plants are studied in all the four quadrats. Here the data of the plant A, B, C, D and E has been assumed and frequency and density is calculated.

Advantages of the quadrat method for studying the density of an ecosystem are:

1. It is quite easy to use it.
2. It is relatively inexpensive.

Disadvantages of the quadrat method for studying the density of an ecosystem are:

1. If measurement of larger area has to be done, then it is quite cumbersome process to accomplish.
2. Larger measurements, no doubt leads to errors.

Advantages and disadvantages of the quadrat method to study the frequency of an ecosystem is same as the bove method.