EVE UNIT 3

Definition of Biodiversity

Biodiversity refers to all living organisms in an ecosystem, encompassing various species and environmental factors such as oxygen levels, climate, and temperature. It reflects the variety of life on Earth, including microorganisms and fungi, and can be measured globally or in smaller habitats like ponds.

Types of Biodiversity

Genetic Diversity

Refers to the genetic variations within a species and among different species, involving differences in DNA/RNA sequences. For example, humans exhibit diversity in skin color, height, and other traits despite belonging to the same species. Similarly, plants can adapt to different environments, exemplified by diverse species of mangrove trees.

Species Diversity

Involves the variety and distribution of species in an ecosystem, often characterized by species richness which indicates the number of different species present. Introduction of concepts like species richness distinguishes quantifying species from their distribution.

Ecosystem Diversity

Denotes the variety of ecosystems within a region, including primary habitat types like terrestrial, aquatic, and marine systems. Subgroups such as coral reefs and mangrove systems illustrate the diversity found within these broader categories.

Values of Biodiversity

  • Environmental Value: Recognizes the ecosystem processes that yield benefits such as nutrient cycling and oxygen production.

  • Social Value: Includes aesthetic, cultural, spiritual, and recreational benefits which contribute to wellness and health.

  • Economic Value: Encompasses the potential for food, medicines, and other resources derived from biodiversity.

  • Consumptive Use Value: Focuses on natural products used for food and energy that we consume directly.

  • Productive Use Value: Relates to products that are harvested for commercial use.

  • Ethical and Moral Value: Stresses the importance of conserving biodiversity for the intrinsic right of all life forms to exist.

  • Aesthetic Value: Enhances the beauty of the planet, enriching the quality of life.

Threats to Biodiversity

  • Habitat Loss: Due to activities like agriculture, urban development, and logging, leading to the depletion of natural habitats.

  • Poaching: Illegal hunting affecting wildlife populations.

  • Human-Wildlife Conflict: Occurs when human expansion leads to resource competition.

  • Climate Change: Alters species distribution and increases extinction risks.

  • Pollution: Harmful chemicals released into ecosystems damage flora and fauna.

  • Overexploitation: Unsustainable harvesting of natural resources threatens species survival.

  • Invasive Species: Introduction of non-native species can disrupt local ecosystems.

Human-Wildlife Conflict

This conflict arises from interactions detrimental to both humans and wildlife. Key issues involve property damage, injury to humans, loss of livelihoods, defensively killing wildlife, road accidents, and habitat destruction. Management strategies include cross-sector collaboration and preventive measures.

IUCN Categories of Threat

The IUCN classifies species and ecosystems at risk into categories:

Species Categories:

  • Extinct

  • Extinct in the Wild

  • Critically Endangered

  • Endangered

  • Vulnerable

  • Near Threatened

  • Least Concern

  • Data Deficient

  • Not Evaluated

Ecosystem Categories:

  • Collapsed

  • Critically Endangered

  • Endangered

  • Vulnerable

  • Near Threatened

  • Low Risk

  • Data Deficient

  • Not Evaluated

Biodiversity Hotspots in India

India hosts significant biodiversity hotspots:

  • Sundaland: Home to numerous endemic vascular plant species.

  • Western Ghats: A mountainous region noted for its rich habitats.

  • Indo-Burma: Known for lush tropical forests and high species endemism.

  • Himalayas: Diverse ecosystems influenced by altitude.

  • Dehing Patkai National Park: Celebrated for unique flora and fauna.

Importance of Ecology

Ecology is crucial for understanding environmental impacts, protecting ecosystems, maintaining biodiversity, clean air and water, food production, climate regulation, nutrient recycling, soil fertility, and driving evolutionary processes through genetic diversity.

India as a Biodiversity Nation

India is termed a mega-diversity nation due to its rich biodiversity and numerous ecosystems, including the Himalayas and tropical forests, boasting extensive flora and fauna, including thousands of plant and animal species.

Biogeographic Classification of India

India comprises ten biogeographic zones, each showcasing unique biodiversity, including the Trans-Himalayan region, Indian Desert, Western Ghats, and enriched coastal and island regions.