Question

What is the significance of Biodiversity?

Answer 1

Before we learn about the importance and significance of biodiversity in this biosphere, we must have an idea of what is biodiversity. This specific term was popularized by a socio-biologist named Edward Wilson. It is the combined diversity of species (i.e., the number of different species) at all levels of biological organization (at all trophic levels) within an ecosystem (or a specific area). According to the survey of IUCN in the year 2004, the total number of plants and animal species described so far is slightly more than 1.5 million.

Complete answer:
The number of species of an ecosystem contribute to the proper functioning of an ecosystem. The richness of diversity is directly proportional to the ecosystem’s stability, productivity, resilience, alternative pathways and overall health of the ecosystem.
Some of the major points are discussed below:
A. STABILITY: Studies have found that communities that have more diversity are more stable than communities having less diversity. Now, there are some criteria by which one can term a community to be a stable one:
A stable community does not show much variation in its GPP (Gross primary productivity) from year to year.
It must be able to offer good resistance to natural calamities as well as man-made disturbances.
It should be able to resist attacks of alien species.
Experiments termed as ‘long term ecosystem experiments’ which were performed by David Tilman confirmed that the above said attributes are directly linked with species richness. It was confirmed that:
Plots with more species showed less year-to-year variation in total biomass.
Increased diversity contributed to higher productivity.
B. ECOSYSTEM HEALTH: This fact tells us that each of the species has a definite role in the ecosystem and ecological niches. If a few species become extinct then it may not affect the ecosystem so much but eventually, if the trend continues, the stability of the system may get hampered. This is because a larger number of species have a higher number of niches, more interactions occur between them and thus there are more inter-relationships.
This thing can be best explained with Paul Ehrlich’s Rivet popper hypothesis.
In an airplane (which represents the ecosystem here), all parts are joined using rivets (species). If every passenger travelling in it starts popping a rivet to take home (causing a species to become extinct), it may not have any effect on flight safety initially. But, with more and more rivets going on missing, eventually, the airplane would be dangerous to operate.
The same happens in the case of ecosystems.
Further, the rivet which is removed from which part is also taken into consideration. Loss of rivets on wings (keystone species) is obviously a more serious threat to flight safety than a rivet which is removed from the seats or doors.
C. ECONOMICAL USES: The ecosystems provide us with countless beneficial things that are useful to us for our economical needs as well as for our survival like timber, firewood, foods (cereals, grains, fruits, vegetables, etc.), industrial products like resin, herbal medicines (drugs like quinine).
D. ECOSYSTEM SERVICES: These are broadly utilitarian services that nature provides us like Oxygen, Pollination, Flood and erosion control, etc.
Thus, ecosystems are of great importance to this whole biome.

Note:
Some terms to remember here are:
Species richness: Species richness is the number of species in a defined region.
Keystone species: These are the species that have a marked ecological role in an ecosystem, although their numbers are low. For example, there are only 2-3 lions present in an ecosystem but it is a major carnivore of the whole food chain and also the king of the jungle.
There is another significance of ecosystem services known as Ethical importance. This is a theory actually which signifies and justifies the fact that no organism is useless and each and every organism has a definite role in the environment.