3.3 Biodiversity and its importance

Biodiversity is the spice of life on Earth. It's not just about counting species; it's about the intricate web of genes, organisms, and ecosystems that make our planet thrive. From tropical rainforests to deep-sea vents, biodiversity shapes the world we live in.

Understanding biodiversity is key to protecting our environment. It's not just about saving cute animals; it's about maintaining the delicate balance that supports all life, including us. Biodiversity provides food, medicine, clean air, and water – it's the ultimate life support system.

Biodiversity: Levels and Values

Defining and Measuring Biodiversity

Top images from around the web for Defining and Measuring Biodiversity

• 

  5.2 Origin of Biodiversity | Environmental Biology View original

  Is this image relevant?

• 

  Taxonomy | Biology for Non-Majors I View original

  Is this image relevant?

• 

  ESS Topic 3.1: Introduction to Biodiversity - AMAZING WORLD OF SCIENCE WITH MR. GREEN View original

  Is this image relevant?

• 

  5.2 Origin of Biodiversity | Environmental Biology View original

  Is this image relevant?

• 

  Taxonomy | Biology for Non-Majors I View original

  Is this image relevant?

1 of 3

Top images from around the web for Defining and Measuring Biodiversity

• 

  5.2 Origin of Biodiversity | Environmental Biology View original

  Is this image relevant?

• 

  Taxonomy | Biology for Non-Majors I View original

  Is this image relevant?

• 

  ESS Topic 3.1: Introduction to Biodiversity - AMAZING WORLD OF SCIENCE WITH MR. GREEN View original

  Is this image relevant?

• 

  5.2 Origin of Biodiversity | Environmental Biology View original

  Is this image relevant?

• 

  Taxonomy | Biology for Non-Majors I View original

  Is this image relevant?

1 of 3

• Biodiversity encompasses the variety of life forms within ecosystems, biomes, or the entire Earth
  • Includes diversity of genes, species, and ecosystems
• Three interconnected levels of biodiversity influence each other
  • Genetic diversity: Variation in genes within a single species
    • Crucial for adaptation and evolution
  • Species diversity: Variety of different species within a given area
    • Measured by species richness and evenness
  • Ecosystem diversity: Variety of habitats, communities, and ecological processes
• Measurement methods use various indices
  • Shannon-Wiener index accounts for species richness and evenness
  • Simpson's diversity index considers probability of two random individuals belonging to different species
• Multi-scale understanding essential for effective conservation
  • Ranges from local to global perspectives

Ecological and Economic Importance

• Ecological value stems from maintaining ecosystem stability and productivity
  • Contributes to ecosystem resilience against disturbances
• Biodiversity provides essential ecosystem services
  • Nutrient cycling supports soil fertility
  • Pollination enables plant reproduction (bees, butterflies)
  • Seed dispersal aids in plant distribution (birds, mammals)
  • Climate regulation through carbon sequestration (forests, oceans)
• Economic benefits derived from biodiversity
  • Food sources (crops, livestock, fish)
  • Medicine (plant-based pharmaceuticals)
  • Raw materials (timber, fibers)
  • Genetic resources for agriculture and biotechnology
• Ecosystem services quantify economic value
  • Regulating services (flood control, water purification)
  • Cultural services (ecotourism, recreational activities)

Cultural Significance and Intrinsic Worth

• Integral to cultural, spiritual, and religious practices
  • Sacred groves in India preserve biodiversity
  • Totem animals in indigenous cultures
• Contributes to human well-being and cultural identity
  • Traditional ecological knowledge passed through generations
• Inspires art, literature, and scientific discovery
  • Nature-inspired art movements (Romanticism)
  • Biodiversity as a subject in literature (Silent Spring by Rachel Carson)
• Intrinsic value recognizes inherent worth of species and ecosystems
  • Independent of utility to humans
  • Ethical considerations in conservation efforts

Global Biodiversity Patterns

Latitudinal and Altitudinal Gradients

• Latitudinal gradient of species richness
  • Biodiversity increases from poles to tropics
  • Tropical regions harbor highest species diversity (Amazon rainforest)
• Factors influencing latitudinal gradient
  • Energy availability and productivity
  • Evolutionary time and stability
  • Habitat complexity
• Altitudinal gradients affect species distribution
  • Diversity often decreases with increasing elevation
  • Mid-elevation peaks occur in some regions (Andean cloud forests)
• Reasons for altitudinal patterns
  • Temperature and precipitation changes
  • Reduced land area at higher elevations
  • Isolation and speciation processes

Marine and Terrestrial Biodiversity Distribution

• Marine biodiversity patterns differ from terrestrial
  • Coastal areas and coral reefs have higher biodiversity (Great Barrier Reef)
  • Unique patterns in deep-sea ecosystems (hydrothermal vent communities)
• Factors influencing marine biodiversity
  • Temperature gradients
  • Ocean currents and upwelling zones
  • Habitat complexity (coral reefs, kelp forests)
• Terrestrial biodiversity hotspots
  • Regions with high species richness and endemism
  • Often face significant threats from human activities (Madagascar, Caribbean Islands)
• Island biogeography theory explains biodiversity patterns
  • Island size and distance from mainland affect species diversity
  • Equilibrium between colonization and extinction rates

Biome-Specific Patterns and Endemism

• Different biomes exhibit distinct biodiversity patterns
  • Tropical rainforests (highest species richness)
  • Temperate grasslands (adapted to seasonal changes)
  • Tundra (specialized cold-adapted species)
• Factors influencing biome-specific patterns
  • Climate conditions
  • Vegetation structure
  • Evolutionary history
• Endemism occurs when species are unique to particular locations
  • Influenced by isolation and evolutionary processes
  • Examples: Lemurs in Madagascar, Kangaroos in Australia
• Factors contributing to endemism
  • Geographic barriers (mountains, oceans)
  • Long-term isolation
  • Unique environmental conditions

Biodiversity and Ecosystem Resilience

Ecosystem Resilience Concepts

• Ecosystem resilience defined as ability to maintain core functions despite disturbances
  • Includes resistance to change and recovery capacity
• Insurance hypothesis suggests higher biodiversity enhances stability
  • Provides buffer against environmental fluctuations
• Functional redundancy increases ecosystem resilience
  • Multiple species perform similar ecological roles
  • Provides functional backup if some species are lost
• Diversity-stability hypothesis proposes more diverse ecosystems are more stable
  • Greater diversity leads to increased resistance and recovery potential
• Keystone species and ecosystem engineers crucial for maintaining structure
  • Beavers create wetland habitats
  • Sea otters maintain kelp forest ecosystems

Mechanisms of Biodiversity-Resilience Relationship

• Biodiversity contributes to ecosystem resistance
  • Diverse plant communities better withstand drought
  • Varied pollinator species ensure continued pollination services
• Recovery capacity enhanced by biodiversity
  • Seed banks allow for rapid revegetation after disturbance
  • Diverse microbial communities aid in soil recovery
• Cascading effects of biodiversity loss
  • Loss of top predators can lead to trophic cascades
  • Decline in native plant diversity can increase invasive species success
• Threshold effects and regime shifts
  • Biodiversity loss can trigger ecosystem collapse when critical thresholds are crossed
  • Coral reef bleaching leading to algal-dominated systems
• Adaptive capacity linked to genetic diversity
  • Enables species to evolve in response to environmental changes
  • Increases likelihood of beneficial mutations