S = CA², where
S = species richness
A = area
C = V-intercept
1. Alexander Von Humboldt observed that within a region, species richness increased with increasing explored area, but only upto a limit.
2. The relation between species richness and area for a wide variety of taxa like angiosperms, birds, fishes, etc. turns out to be a rectangular hyperbola.

1. Ahmad Khan started manufacturing polyblend from plastic wastes.
2. Polyblend is a fine powder of recycled and modified plastic.
3. Polyblend is mixed with bitumen that is used to lay roads.
4. Polyblend is found to enhance the water repelling property of bitumen and increased the life of road by a factor of three.
5. Using this technique, about 40 km of road was laid by the year 2002.
6. At this rate, it is expected that Khan will be running short of plastic wastes.

It is a case of mutualism because both the fig tree and the wasp are benefitted by this interaction.
The female wasp uses the ovary as a site for oviposition and the developing seeds within the fruit for nourishing the larvae.
The fig inflorescence is pollinated while the wasp is searching for the suitable place for egg-laying.

This is may be due to any following reasons:
(i) Fast growing species may compete with less vigorous local species.
(ii) Alien species will proliferate in that area if their natural pests and predators are not present.
(iii) by amensalism i.e. it may vigorously and may form conditions unfavorable for growth of local native species like Eichhornia.

(a) Catalytic converters are recommended in automobiles to reduce air pollution by their exhaust.
1. Catalytic converters have metal like rhodium, palladium and platinum, which convert the unburnt hydrocarbons into carbon dioxide and water, carbon monoxide into carbon dioxide and nitric oxides into nitrogen.
(b) Only unleaded petrol must be used in such vehicles as lead would inactivate the catalyst.
(c) CNG is preferred as a fuel because
(i) it burns efficiently ill the vehicles and very little of it is left unburnt.
(ii) it cannot be adulterated.

(I) When resources are limiting, the population growth curve is sigmoid and it is represented by the equation:
\(dN/dt=rN\left( \frac { K-N }{ K } \right) \), where
N = population density at time t
r = intrinsic rate of natural increase
K = carrying capacity
When resources are not limiting, the growth curve is J shaped and is represented by the equation: dN/dt = rN 
\(N_{ t }={ N }_{ 0 }^{ e^{ rt } },where\)
\(N_{ t }\) =population density after time t
\(N_{ 0 }\)= population density at time zero
r = intrinsic rate of natural increase
e = the base .of  natural logarithm (2.71828)

Warm water can hold much less dissolved oxygen than cold water. Also, rise in temperature speeds up animal metabolism increasing O₂ requirement thus further aggravating O₂ problem for aquatic animals.

(i) As the BOD increases, the amount of dissolved oxygen in the water body decreases sharply from the point of sewage discharge.
(ii) This causes mortality of fish and other aquatic organisms.
Excess presence of nutrients in the water causes algal bloom, which also causes fish mortality.