What changes population densityसमष्टि घनत्व किससे बदलता है

NCERT Fig 11.2 · Class 12 Biology · Chapter 11 · interactive diagram

Parts and their functions

• Population density (N) (समष्टि घनत्व (N)) — Population size; usually counted as numbers, but per cent cover or biomass may be more meaningful (e.g. one huge banyan vs 200 Parthenium plants).
• Natality (B) (जन्मदर (B)) — Number of births during a given period that are added to the initial density. Increases N.
• Mortality (D) (मृत्युदर (D)) — Number of deaths in the population during a given period. Decreases N.
• Immigration (I) (आप्रवासन (I)) — Individuals of the same species that come into the habitat from elsewhere during the period. Increases N; can matter most when a new habitat is being colonised.
• Emigration (E) (उत्प्रवासन (E)) — Individuals of the population who leave the habitat and go elsewhere during the period. Decreases N.
• Nt+1 = Nt + [(B + I) − (D + E)] (Nt+1 = Nt + [(B + I) − (D + E)]) — Density grows if births + immigrants (B + I) are more than deaths + emigrants (D + E). Normally births and deaths matter most.

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 11.2. Report a mistake