Biotic Potential

It is defined as an inherent capacity of females to conceive and deliver babies in their reproductive life. It is also called as fecundity. This varies largely from individual to individual. It is usually studied on mean basis for the entire population. The study of biotic potential is useful to understand the maximum ceiling to which the population can grow. It is also useful to decide what percent of biotic potential is necessary to be exploited to achieve the expected growth rate. All birth control measures are aimed at ways and means to under utilize the biotic potential, although they cannot reduce the biotic potential itself.

The fecundity (biotic potential) has direct relationship with growth rate of population, although the level of exploitation of fecundity is more decisive in deciding growth rate. In general, fecundity of females in European community is less and European countries have recorded zero or negative growth rate. In contrast, fecundity of Asian women is high and growth rate in general is high.

At a global level, biotic potential of females (for age group of 14 to 50 years) is 12 per every female.

Carrying Capacity

It is defined as the capacity of environment or an ecosystem to support and sustain a level of population under an ideal set of conditions.

Carrying capacity is a ceiling of population, beyond which the environment fails to support the population leading to natural decrease in population. Usually when population growth reaches this phase - zero growth is achieved.

Carrying capacity of earth for human beings is calculated to be 8 - 15 billion. But, if individual country or individual cities are considered, carrying capacity of such regions is nearing full exploitation. In many other countries it is not fully exploited.

Example:Some countries are thickly populated while others extremely thin population exists. Thickness of population is studied based on density of population.

Country	Density of population No / Km2		Country	Density of population No / Km2
Malta	3157		Russia	22
San Marino	1166		Turkmenistan Mongolia	78 4
Maldives	2469		Finland	40
Singapore	16714		Iceland	7
Hong Kong	16949		Norway	36
South Korea	1234		Sweden	51
Monaco	45333		Guyana	8
Bangladesh	2305		Australia	6
Mauritius	1510		Oman	29
Barbados	1560		Congo	21
Namibia	6		India	789

 

In such thickly populated countries, the testimonies of population holocaust explosion are already observed.

Environmental Resistance

Also referred to as population regulation, it means the total of all inhibitory factors naturally regulating the growth of population. The environment puts up its resistance after a level often less than biotic potential or even carrying capacity. Such resistance may be in the form of changes in environment, natural calamities (drought, cloud burst, flood, fire, accidents) or self imposed wars, riots, terrorism etc.

All such resistance checks the population to a level below the carrying capacity. It is a sort of reaction by environment to cut the size of population to the level it can support.