Question
Define species-area relationship pattern of biodiversity in detail.
✓
Answer
Species area relation : The famous German naturalist and geographer Alexander von Hemboldt, while working in the forests of South America, pointed out that to some extent the species richness of an area depends on increasing the extent of the exploration area. In fact, the relationship between species richness and the area of a wide variety of taxa (gymnosperms, birds, bats, freshwater fishes) is rectangular hyperbola.
On a logarithmic the relationship is a straight line described by the equation :
$\log S =\log C + Z \log A$
where S = species richness, A = Area,
Z-slope of line (regression coefficient), C = Y—intercept
Ecologist have reported that the value of Z lies in the range of 0.1 to 0.2 regardless the taxonomic group of the region (whether it is the plant in Britain, birds in California, all mollusc in New York State, slopes of the regression line are amazingly similar). But, if we analyze the species area relationship among very large areas like the entire continent, we will find that the slope of the line to be much steeper (as the Z-value in the range of 0.6 to 1.2). For example : for frugivorous (fruit eating) birds and mammals in the tropical forest of the different continents, the slope comes to be 1.15 which represents the dense species richness over the wide area.
On a logarithmic the relationship is a straight line described by the equation :
$\log S =\log C + Z \log A$
where S = species richness, A = Area,
Z-slope of line (regression coefficient), C = Y—intercept
Ecologist have reported that the value of Z lies in the range of 0.1 to 0.2 regardless the taxonomic group of the region (whether it is the plant in Britain, birds in California, all mollusc in New York State, slopes of the regression line are amazingly similar). But, if we analyze the species area relationship among very large areas like the entire continent, we will find that the slope of the line to be much steeper (as the Z-value in the range of 0.6 to 1.2). For example : for frugivorous (fruit eating) birds and mammals in the tropical forest of the different continents, the slope comes to be 1.15 which represents the dense species richness over the wide area.
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