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Investigating Population; Random sampling; what is transects? How does it work?

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Introduction

Investigating Population; Random sampling; what is transects? How does it work? A group of interbreeding organisms of one species in a habitat is referred to as a population. Investigating the population is part of ecology, which is the study of inter-relationships between organisms and their environment. Eventually, it is necessary to count the number of individuals of a species in a given habitat. However, it is impossible to count all the number of individuals of a species of given habitat because the process is time consuming and could cause damage to the habitat. To overcome these issues, random sampling using quadrates and systematic sampling along transects are used. Random sampling can be carried out by dividing the study into a grid of numbered lines, e.g. ...read more.

Middle

point quadrat - consists of a horizontal bar supported by two legs. A point frame consisting of a group of 10 pins set about 5 cm apart is normally used. The pins are lowered in turn and the number of hits and misses on the particular species of plant under consideration is recorded. 2. A frame quadrat - a square frame divided by string or wire into evenly sized sections. Altogether, both types of quadrates produce quantitative results. Systematic sampling along transects is more informative to measure the number of individuals of a species in a given space in a systematic rather than a random manner. ...read more.

Conclusion

{Figure 2 represents a frame quadrat}. Both the process involves reasons, such as chance affecting the sampling. Therefore the results may not be representative. For example, the 50 buttercup plants selected might just happen to be the tallest in the population. Even though we cannot remove chance from the sampling process completely, we can minimise the effect by using a large sample as well as analysis the data that is collected carefully. Using a large sample size will reduce the effect of chance; as more individuals are selected, the results are less deviating far from accurate mean value. at the same time, analysing the data collected carefully, which involve accepting that chance will play a part and using statistical tests to determine the extend to which chance may have influenced the data could also minimise the effect of chance. ...read more.

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