What is ecological density, crude density and population density ?

Explanation

(i) Crude density : is the size of population in relation to numbers per unit of space. Eg : 1000 fish in a pond.
(ii) Ecological density : It is the size of the population in relation to the numbers per unit of habitat space. Eg : 1000 fish in the volume of water in the pond.
(iii) Population density : It is usually expressed as the number of individuals per unit area or volume. Eg : 100 trees per acre.