One of a number of samples taken at regular intervals, e.g. by the use of regularly spaced quadrats along some environmental gradient such as a valley side. Though less reliable in certain circumstances than random sampling, systematic sampling may be more practicable and more economical in the time it takes. The chief disadvantages are the possibility that the interval selected may resonate with some unsuspected environmental variable, so giving biased results, and that the form of the sample does not conform with that theoretically assumed for many statistical tests.
Subjects: Plant Sciences and Forestry.