Question

Which of the following equations best represents the formula for calculating the change in population density?

• A. $N_{t+1}=N_t+\left[\right(B+D)-(I+E\left)\right]$
• B. $N_t=N_{t+1}+\left[\right(B+D)-(I+E\left)\right]$
• C. $N_{t+1}=N_t+\left[\right(B+I)-(D+E\left)\right]$
• D. $N_{t+1}=N_t+\left[\right(B+I)+(D+E\left)\right]$

Answer 1

The correct option is A $N_{t+1}=N_t+\left[\right(B+D)-(I+E\left)\right]$

Population density is the number of individuals per unit area at a given time. If the initial population density at time t is $N_t$, then the population density at time t+1 can be represented as

$N_{t+1}=N_t+\left[\right(B+I)-(D+E\left)\right]$Where,

B is natality i.e. number of births during a given time period

I is immigration i.e. number of individuals of the same species that enter a population from elsewhere during a given time period

D is mortality i.e. number of deaths during a given time period

E is emigration i.e. number of individuals of the same species that leave a population during a given time period.