Lecture Notes: The World's Coldest Biomes - Tundra and Ice
Introduction
- The sun's reach is weak at the Earth's poles, resulting in freezing temperatures.
- The two primary cold biomes are the Arctic (tundra) and Antarctic (ice).
- These biomes experience extreme cold due to oblique sunlight angles and minimal solar heating.
Characteristics of Tundra and Ice Biomes
Tundra
- Summer temperatures rarely exceed 10°C, preventing tree growth.
- Only hardy shrubs, herbs, moss, and lichen can grow.
- Found bordering the Arctic Ocean, from North America to Russia.
- Features permafrost: permanently frozen soil layer.
- Short summer growing season of 50-60 days.
- Dominant flora includes lichen, moss, sedges, cotton grass, and low willows.
- Fauna includes polar bears, reindeer, caribou, musk-ox, arctic wolves, hares, foxes, and lemmings.
Ice Biome
- Permanently covered by ice where temperatures never rise above 0°C.
- No plant life due to permanent frost and extensive ice.
Climate Zones and Lifezones
- Overlaps with climate zones named Arctic and Antarctic.
- Holdridge Lifezones chart positions tundra and ice in the top rows.
- Term 'desert' applies due to lack of life.
- Tundra and ice also found in high-altitude areas worldwide.
Threats and Environmental Impact
- Minimal direct human threat due to sparse populations.
- Climate change poses risks such as melting permafrost and icecaps.
- Melting releases methane and contributes to rising sea levels.
Conclusion
- Tundra and ice are the final biomes in the LONS08 classification system.
- Awareness of these biomes is crucial as part of understanding global biodiversity and climate change.
- The series covered various biomes, emphasizing biodiversity and environmental challenges.
Additional Information
- Related episodes on climate zones are available for deeper exploration.
- Encouragement to engage with more content and further series.
- Call to action for viewers to support and share content related to environmental education.
Note: This lecture emphasizes the ecological significance and challenges faced by the coldest biomes, urging awareness of climate impacts on these regions.