Belt transect
Encyclopedia
Belt transects are used in biology
to investigate the distribution of organism
s in relation to a certain area, such as the seashore
or a meadow. It records all the species
found between two lines and how far they are for a certain place or area and how many of them there are. An interrupted belt transect records all the species found in quadrat
s (square frames) placed at certain intervals along a line.
The belt transect method is similar to the line transect
method but gives information on abundance as well as presence, or absence of species. It may be considered as a widening of the line transect to form a continuous belt, or series of quadrats.
In this method, the transect line is laid out across the area to be surveyed and a quadrat is placed on the first marked point on the line. These marked points should be a set amount of space apart. The plants and/or animals inside the quadrat are then identified and their abundance estimated. Animals can be counted within the quadrat, or collected, while it is usual to estimate the percentage cover of plant species. Cover is the area of the quadrat occupied by the above-ground parts of a species when viewed from above. The canopies of the plants inside the quadrat will often overlap each other, so the total percentage cover of plants in a single quadrat will frequently add up to more than 100%.
Quadrats are sampled all the way down the transect line, at each marked point on the line, or at some other predetermined interval (or even randomly) if time is short. It is important that the same person should do the estimations of cover in each quadrat, because the estimation is likely to vary from person to person. If different people estimate percentage cover in different quadrats, then an element of personal variation is introduced which will lead to less accurate results. Sampling should always be as least destructive as possible and you should try not to trample an area too much when carrying out your survey. (Not because it is not right but also because it will ruin your results as you are lowering the population.)
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
to investigate the distribution of organism
Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...
s in relation to a certain area, such as the seashore
Coast
A coastline or seashore is the area where land meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs...
or a meadow. It records all the species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
found between two lines and how far they are for a certain place or area and how many of them there are. An interrupted belt transect records all the species found in quadrat
Quadrat
A quadrat is a square used in ecology and geography to isolate a sample, usually about 1m2 or 0.25m2. The quadrat is suitable for sampling plants, slow-moving animals , and some aquatic organisms.When an ecologist wants to know how many organisms there are in a particular habitat, it would not be...
s (square frames) placed at certain intervals along a line.
The belt transect method is similar to the line transect
Line-intercept sampling
In statistics, line-intercept sampling is a method of sampling elements in a region whereby an element is sampled if a chosen line segment, called a “transect”, intersects the element ....
method but gives information on abundance as well as presence, or absence of species. It may be considered as a widening of the line transect to form a continuous belt, or series of quadrats.
In this method, the transect line is laid out across the area to be surveyed and a quadrat is placed on the first marked point on the line. These marked points should be a set amount of space apart. The plants and/or animals inside the quadrat are then identified and their abundance estimated. Animals can be counted within the quadrat, or collected, while it is usual to estimate the percentage cover of plant species. Cover is the area of the quadrat occupied by the above-ground parts of a species when viewed from above. The canopies of the plants inside the quadrat will often overlap each other, so the total percentage cover of plants in a single quadrat will frequently add up to more than 100%.
Quadrats are sampled all the way down the transect line, at each marked point on the line, or at some other predetermined interval (or even randomly) if time is short. It is important that the same person should do the estimations of cover in each quadrat, because the estimation is likely to vary from person to person. If different people estimate percentage cover in different quadrats, then an element of personal variation is introduced which will lead to less accurate results. Sampling should always be as least destructive as possible and you should try not to trample an area too much when carrying out your survey. (Not because it is not right but also because it will ruin your results as you are lowering the population.)