Biomes and Ecosystems Quiz

Biomes and Ecosystems

• Biomes are distinct ecosystems defined by climate and dominant producers.
• Biome structure is primarily determined by the producers (first trophic level).
• Convergent structures (similar, but different species) exist across continents in comparable biomes.
• Key factors influencing biome distribution and structure include: climate (major influence), fire, soil, herbivores, and producers.
• Terrestrial biomes may span globally, exhibiting similar climate characteristics (latitude, precipitation, temperature) while having different species.

Terrestrial Biome Types

• Forests: Ecosystems dominated by trees (10+ meters tall).
• Shrubs: Woody plants with multiple stems, smaller than trees.
• Herbs: Non-woody plants (e.g., grasses).
  • Forests develop in areas with adequate precipitation and moisture.

Climate Parameters

• Climate is described using Mean Annual Precipitation (MAP) and Mean Annual Temperature (MAT).
• Different climate zones (e.g., tundra, boreal forest, temperate forest, tropical rainforest, etc.) are associated with specific biomes based on temperature-precipitation relationships.

Tropical Forests

• Rainforests: Characterized by little seasonal variation, tall trees, broad-leaved evergreen trees, high rainfall, and equatorial location.
• Dry forests: Experience longer dry seasons, deciduous trees (shed leaves during dry periods), and have substantial shrubbery and other plants.

Tropical Savanna

• Savannahs are grasslands with scattered trees.
• Savannas are differentiated from dry forests by their dominant grasses.
• Frequent fires are common in savannas.

Deserts

• Deserts are dry ecosystems often formed by descending air masses with high pressure.
• They are too dry for substantial tree growth.
• Deserts exhibit a wide temperature range - both hot and cold deserts exist.
• Deserts are dominated by shrubs, succulents (e.g., Joshua trees), or sparse grasses.

Mediterranean Shrubland

• Found at approximately 30-35 degrees latitude in various locations (Southern Africa, Southern Australia, parts of Chile, California, Mediterranean).
• Characterized by winter rainfall and hot, dry summers.
• Dominated by evergreen shrubs with small, hard, flammable leaves.
• Often harbors many endemic (unique to an area) species.

Temperate Grassland

• Located in areas approaching 60 degrees latitude.
• Dry continental climate, frequent fires, and lack of significant moisture are typical traits.
• Seasonal precipitation patterns are observed.

Temperate Forests

• Located in coastal areas at the same latitudes as temperate grasslands.
• Comprises broad-leaved forests (deciduous or evergreen, including eucalyptus).
• Deciduous forests result from dry winters, whereas evergreen forests thrive in milder winters.
• Broad-leaved forests are angiosperms.

Northern Coniferous Forest

• Dominated by gymnosperms (needle-leaved trees).
• Includes sub-categories:
  • North American temperate rainforests
  • Boreal forests, characterized by cold winters, short summers with trees that tolerate long frost periods.
• Needle-leaved, evergreen trees are common due to cold winters and short growing seasons.

Tundra

• Tundra biomes are too cold for tree growth, with short, cool summers and long, cold winters.
• Dominated by shrubs and grasses, with permanently frozen soil.

Mountain Biomes

• Mountain ecosystems exhibit distinct climate zones, with temperatures decreasing with increasing altitude (approximately 6 degrees Celsius for every 1000 meters).
• Biodiversity varies across different altitude zones.

Aquatic Biomes

• Water covers 75% of Earth's surface, largely ocean (71%).
• Includes a variety of fresh water sources (lakes, rivers, groundwater, ice).
• Major processes in the water cycle are evaporation, condensation, precipitation, and runoff.
• Aquatic productivity is controlled by light penetration and nutrient availability.

Ocean Zones

• Photic zone: Surface water layer where light penetrates sufficiently for photosynthesis (~150 meters).
• Twilight zone: Below the photic zone, with limited light penetration.
• Oceanic zone: Deeper water beyond the continental shelf with lower nutrient availability.

Coastal Zone

• The coastal zone over the continental shelf is highly productive due to sunlight penetration and nutrient influx.
• Kelp forests thrive in cold and temperate coastal waters.
• Coral reefs exist in shallow tropical waters.