Ecosystem pressure part 2


Distribution is the geographical area with which you can find a plant or animal. Where as, abundance is how many animals you would expect to find within the region it is distributed.

The wētā is an insect which looks like a large grass hopper and is distributed through out New Zealend. Its highly abundant since it densely populates the area.

In order to measure plant abundance a 1*1 m square can be placed on the ground and all the plants within that square are counted. This is then repeated randomly placing the square in different area’s another four times and counting how many plants appear in each area. Then averaging the total number of each species of plants counted and multiplying by the total area will give the abundance of plants within that area.

In order to measure animal abundance capture and tag can be used. This counts the number of times an animal is recaptured. Using statistical means the abundance of a particular species can then be estimated.

Ecology is a field in biology which studies ecosystems. The field is concerned with the interaction between flora and fauna and the environment. They consider the interactions between biotic and abiotic factors and can predict and propose ways of sustaining and regrowing an environment.


Question 1 (5 marks)

Calculate the abundance of plant 1, plant 2, plant 3 using the sampling method with 1*1 m square.

Count the number of plants in each square and compare this to previous part. What is a limitation of the previous method and what makes it more suitable over vast distances?

Question 2 (1 mark)

Define the term ecology

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