Question

What are the major terrestrial ecosystems of the world with their groups of climax biotic community called?

• A. Habitats
• B. Biospheres
• C. Biomes
• D. Communities

Answer 1

Answer:

C. Biomes

Understanding Biomes

• A Biome is a large-scale ecological unit characterized by its distinctive climate, dominant vegetation type, and associated animal life. It represents a major regional or global type of ecosystem.
• The distribution of biomes across the Earth is primarily determined by climate, specifically temperature and precipitation patterns.
• Biomes are essentially a collection of ecosystems sharing similar climatic conditions and ecological characteristics.

Climax Biotic Community

• A climax biotic community refers to the stable, mature, and self-sustaining ecological community that develops over time in a given area, representing the final stage of ecological succession.
• Within a biome, the dominant vegetation (e.g., coniferous trees in Taiga, grasses in Grasslands) forms the core of its climax biotic community, which dictates the type of animal life it can support.

Major Terrestrial Biomes

• 1. Tundra

  • Characterized by extremely cold temperatures, low precipitation, and a short growing season.
  • Presence of permafrost (permanently frozen subsoil) which prevents the growth of deep-rooted trees.
  • Dominant vegetation includes mosses, lichens, sedges, and dwarf shrubs. Animals like reindeer, arctic foxes, and polar bears are common.

• 2. Taiga (Boreal Forest)

  • The largest terrestrial biome, found south of the tundra.
  • Dominated by coniferous trees (e.g., spruce, fir, pine) adapted to long, cold winters and moderate to high precipitation.
  • Animals include moose, bears, wolves, and various furbearing mammals.

• 3. Temperate Deciduous Forest

  • Found in mid-latitude regions with moderate temperatures and significant seasonal changes (four distinct seasons).
  • Characterized by trees that shed their leaves in autumn (e.g., oak, maple, beech).
  • High biodiversity with a rich understory vegetation and various mammals, birds, and insects.

• 4. Grasslands

  • Comprise vast areas dominated by grasses, with few or no trees, due to semi-arid conditions and recurring fires.
  • Divided into:
    • Temperate Grasslands (e.g., Prairies in North America, Steppes in Eurasia, Pampas in South America) with hot summers and cold winters.
    • Tropical Grasslands (Savannas) (e.g., in Africa, Australia, South America) with high temperatures and distinct wet and dry seasons.
  • Support large grazing animals (e.g., bison, antelope, zebras) and their predators.

• 5. Deserts

  • Regions characterized by extremely low precipitation (less than 25 cm annually).
  • Can be hot deserts (e.g., Sahara, Arabian) or cold deserts (e.g., Gobi, polar regions).
  • Vegetation is sparse and adapted to drought (e.g., cacti, succulents); animals are often nocturnal or have specific adaptations for water conservation.

• 6. Tropical Rainforests

  • Found near the equator, characterized by high temperatures and high rainfall year-round.
  • Known for the highest biodiversity among all terrestrial biomes, with multiple layers of vegetation.
  • Home to a vast array of plant and animal species, many of which are endemic.

• 7. Mediterranean (Chaparral)

  • Characterized by hot, dry summers and mild, wet winters.
  • Vegetation consists of drought-resistant shrubs and small trees (e.g., chaparral in California, macquis in France).
  • Known for frequent wildfires.

Important Distinctions & Facts for Competitive Exams

• While a biome is a large-scale unit defined by climate and vegetation, an ecosystem is a smaller, more specific unit comprising living organisms and their physical environment interacting as a functional unit.
• Habitat refers to the specific place where an organism lives.
• The concept of biomes helps in understanding global ecological patterns and biodiversity distribution.
• Global climate change is significantly impacting biome distribution and composition, leading to shifts in species ranges and potential loss of unique ecosystems.
• The study of biomes is crucial for conservation efforts and understanding ecological succession.