Ecological diversity is the intricate network of different species present in different ecosystems and the dynamic interaction between them.
An ecosystem consists of interacting organisms of many different species living together in a region that are connected by the flow of energy and nutrients.
The radiant energy of the Sun provides the ultimate source of energy in nearly all the ecosystems.
The Sun’s radiant energy is converted to chemical energy by the green plants through the process of photosynthesis. This energy flows from the producers to the consumers and lastly to the decomposers.
The following joints characterize the ecological role of biodiversity:
(i) Species diversity:
Biodiversity reflects the natural assemblage of large number of plant and animal species in a given area. It is part of a larger ecosystem in which biotic and abiotic components interact and bring about circulation, transformation and accumulation of energy and matter. A distinct area with uniform habitat conditions and supporting characteristic type of flora and fauna is termed biotope. Each species of a community has got a definite range of tolerance towards the physical and biological environmental conditions of the habitat. The range of environment that a species can tolerate is called its ecological amplitude.
The species occurring in a particular habitat do not live in isolation but coexist with mutual adjustment. The coexisting populations are interrelated and they show some sort of interaction.
The interactions between two coexisting species are of the following types:
Where one species lives at the expense of another.
In this, the coexisting species benefit from the relationship.
In this, the coexisting species compete for the same resources.
In this, the coexisting species are independent of one another.
Here, the different species within a community live under similar environmental conditions and are interdependent on each other,
(iv) Species dominance:
Not all the species of a community are found in abundance. Only a few species are abundant, either in number or in biomass, while the majority of the species are rare. The species that are most common and abundant and contain maximum biomass are known as dominants,
In a plant community, the different plant species are represented by trees, shrubs, herbs, etc. These plants form, more or less, distinct strata or layers on vertical as well as horizontal plains known as stratification,
The interacting species within an ecosystem are characterized by death and replacement, which are continuous processes. In this way, the composition and shape of an ecosystem remains dynamic. This is known as succession. The changes go on taking place until a complete balance is established between the species and the environment.