Question

Study the image given below and select the correct option.


A. $Z=1$ shows that the species richness is less in the area covered.
B. $Z>1$ shows that species richness is more in the area covered.
C. $Z<1$ shows that the species richness is equal to the area covered.

• A. A only
• B. B and C only
• C. A and C only
• D. B only

Answer 1

The correct option is D B only

Alexander von Humboldt, a German naturalist and geographer, proposed the species - area relationships during his extensive explorations in the South American jungles. He observed that, within a region, species richness increased with increasing explored area, but upto a certain limit.
The relationship between species richness and area can be given by the equation
$S=C{A}^z$
where S - Species richness
Z - Slope of line (regression coefficient)
C - Y-intercept
A - Area

On a logirithmic scale, it is given as
log S = log C + Z log A

Graphically it is represented as,


$Z=1$ shows that species richness is equal to the area covered or explored.
$(Z>1)$, means that the species richness is more in the area covered.
$(Z<1)$, means that the species richness is less in the area covered.