The Species-Area Curve
Cain SA. 1938. The Species-Area Curve. The American Midland Naturalist. 19(3):573-581
(1) The so-called species-area curve expresses the relationship between areas of different sizes and the number of species found on those areas. Curves of this sort have been constructed in different ways and used for determining: the minimal area of a community; the minimum quadrat area in the single-plot method; the minimum quadrat area in the multiple-plot method; the least number of quadrats, of minimal size, which will give an adequate sample of a community. (2) The shape of the species-area curve has been used to indicate the minimal area in the above cases. The point on the curve at which the curve flattens strongly and tends to become asymptote with the x axis (on which area is plotted ) is taken to indicate the minimal area. It is shown that the shape of the species-area curve depends on the ratio between the y and x axes which is used in plotting the data. Hence, the shape cannot be used to indicate minimal area, a point overlooked in the literature. The suggestion is made that a better procedure would be to locate the region of the curve where 1/10 increase in are gives 1/10 increase in species. A mechanical method of finding this point on the curve is described. Its location on the curve is independent of the ratio between x and y axes which is used.
- Type
- Journal Article
- Authors
- Cain, Stanley
- Units
- SODN
- Keywords
- Ecology (Community Ecology), Methods (General Field), Species Distribution, species-area curve, Statistics (Biometry Descriptive Mathematics)