MP Board · Class 12 · Biology · Biodiversity and ConservationExplain the three levels of biodiversity in detail. Why is biodiversity important for the ecosystem? (4 Marks)

Biodiversity is a term popularized by sociobiologist Edward Wilson to describe the combined diversity at all levels of biological organization. It can be broadly categorized into three main hierarchical levels:

1. Genetic Diversity

• Genetic diversity refers to the diversity of genes within a particular species.
• A single species might show high diversity at the genetic level over its distributional range.
• For example, the medicinal plant Rauwolfia vomitoria growing in different Himalayan ranges might show variation in the potency and concentration of the active chemical reserpine that it produces.
• India has more than 50,000 genetically different strains of rice and 1,000 varieties of mango.

2. Species Diversity

• Species diversity refers to the variety and richness of species within a particular region.
• The number of species per unit area is known as species richness.
• For example, the Western Ghats have a greater amphibian species diversity than the Eastern Ghats.

3. Ecological Diversity

• Ecological diversity refers to the variety of ecosystems present within a geographical location.
• Ecosystem diversity includes different biological communities, habitats, and ecological processes.
• For example, India with its deserts, rain forests, mangroves, coral reefs, wetlands, estuaries, and alpine meadows has a greater ecosystem diversity than a Scandinavian country like Norway.

Importance of Biodiversity

• Ecosystem Stability: Communities with more species tend to be more stable than those with low species diversity. Rich biodiversity ensures resilience against natural or man-made disturbances.
• Productivity: Increased biodiversity contributes to higher biomass production and efficient nutrient cycling.
• Economic Benefits: Biodiversity provides food, fibers, drugs, medicines, rubber, timber, and recreational values.
• Ecological Services: Ecosystems provide clean air, water, pollination of crops, and climate regulation, which are critical for human survival.