Ecological sampling
Transect sampling
Introduction to Ecological Sampling is impressively both thorough and concise in its coverage of estimating population abundance and other ecological quantities. Therefore, make sure there are enough samples to be representative. Just like when you identify your age, gender, and race in a survey, we can create sub-groups for our ecological sampling. It would be impossible to throw anything larger than a 1m2 quadrat and even this might pose problems. For example, if a plant species exuded a chemical that prevented the growth of other individuals of the same species, the individuals might all be a similar distance from adjacent individuals. A better way to ensure that the samples are truly random would be to impose a coordinate system on the plot and have a computer use a random number generator to select a number of X and Y coordinates within the plot. However, since there is variation among individuals in a population, it is necessary to sample enough individuals to adequately represent the variation.Take a sample from each quarter of the forest, or each sixteenth. A quadrat frame is most often used for this type of sampling. If the area to be sampled known as a plot is not too large, and there are not many plants, it may be possible to sample every plant.
Sampling allows us to get an idea of the bigger picture in manageable ways. The particular type of statistical analysis to be applied to the data whether just descriptive or inferential to sort out relationships and effects will depend on how the data behave patterns of errors, variability, etc.
For the seasoned ecological sampler, the current version of the text may suffice as a textbook for a class on ecological sampling…More than its use in the classroom, I see this book as a great introduction to ecological sampling for the independent learner, whether they are a survey statistician who wants to learn about techniques for ecological examples or an ecologist who wants to learn more about adaptive sampling because they read the phrase in an article.
Continue to random number table and other methods of sampling Can't find what you are looking for? Belt transects are similar to line transects but they allow for a greater area of sampling. Random number Table. What makes this type of sampling random is that the start point is randomized for the predetermined intervals.
A great beauty of this book is its wealth of worked examples based on real problems involving ecological data; the examples are well presented, clear and really easy to follow.
Many of the common statistical techniques used are only valid on data that is truly randomly collected. So sampling a subset of the population is generally the only means to gain an understanding of the population as a whole.
