Population: Ecology, Size, Density, Growth Rate & Curve, Carry capacity, Sex ratio

Population

A population is a group of organisms of the same species, living in an environment or location at the same time interbreeding together.

Population ecology

Is a branch of ecology that deals with the structure and dynamic species population and how this population interacts with the environment.

Population size:

the number of individuals or organisms living in a particular area.

Population density:

the number of individuals or organisms per unit area or volume.

Check out: STUDY OF THE FISH FAUNA AND PHYSICO-CHEMICAL PARAMETERS OF IKPOBA RIVER AT BENIN CITY EDO STATE

Natality:

the number of individuals added to the population through productivity in a given time.

Mortality:

the number of death in a population at a particular time.

Population growth rate:

this is the birth rate – the death rate is expressed in percentage

Survivorship curves:

this is another way of measuring mortality. This curve shows the proportion of individuals likely to survive and individuals that survive within a given cycle.

Four types of survivorship curves

1. Type I: life expectancy will decrease
2. Type II: life expectancy will be Constance
3. Type III and IV: life expectancy will vary.

Sex ratio:

this is the ratio of males to females in a population

Age distribution or structure: the particular age of a population greatly determines the rate of the population

Type of individual in an age distribution

1. Pre productive juvenile
2. Productive adult
3. Post-productive adult

A population that has mainly pre-productive Juvenile are expected to grow in the future, and a population with a mainly productive adult will be growing. But a population with post-productive adults whose productive success is low will face low population

Population growth curve: 

a typical growth curve consists of

1. Log phase
2. Lag phase
3. Stable / equilibrium

Carry capacity:

this is the number of populations that a particular environment can support over a long period of time. And is a number of individuals that can be maintained in a particular environment.