Cold environments are generally found in the high latitudinal regions and mountains of the world. The climate, soil type, flora and fauna found in this region is unique in its own way. However, the biodiversity found here is low as compared to types of environments because of the extreme conditions of climate which makes the survival of life difficult.
Features of polar regions include:
- Long extremely cold winters where temperature falls down below freezing point. Polar regions have very windy atmosphere which is accompanied with little precipitation.
- Soil is covered in ice all year.
- Flora includes many species of moss, lichen and algae which can survive the extreme and harsh situations of the polar ecosystem. Some other plants like bearberry, labrador tea, diamond leaf etc are found in these regions.
- Fauna – Penguin and Polar bear are the most commonly known animals of this region. Earless seal, Killer whale, Sea lion, Walrus and many other types of animal species are found in the polar regions.
Features of the tundra include:
- Climate – Climate is more or less similar to polar regions. It is extremely cold, windy and scanty rainfall. Snow covers the surface for almost all months of the year. Average temperature in the Arctic tundra ranges between -12°C to -6°C. The region witness 50- 60 days of summer each year during which daylight is present all the time.
- Permafrost – It is the layer of frozen soil which is present under the surface of the earth. It can extend as deep as 450 meter in depth. On the higher latitudes this layer remain frozen all year but in the southern parts and lower latitudes, this layer melts in the summer season.
- Soil – Highly organic matter is found in the soil because dead organisms don’t easily decompose in extremely cold conditions.
- Flora – There are negligible trees that can be seen in the tundra but small flowery plants can be seen when snow melts in the summer. Cushion plants can be seen between the rocks in some mountainous areas.
- Fauna – Arctic fox, Reindeer, Snowy owl, Arctic Hare and other many beautiful species can be seen in this region. Goats, Marmots and Sheeps are also found in the mountains. Melted permafrost in the summer season forms shallow lakes which inhabits around it some insects, birds and other wild animals.
Adaptations in plants in cold regions
Plants adapt to survive the extreme conditions of tundra and polar regions. There are many ways plants adapt. These adaptations are both genotypic which means irreversible and phenotypic which means plants modify their structures in response to the external stimuli or conditions.
Plant adapt in following ways in these areas:
- The plants grow close to the ground and remain small in size.
- Plants like moss can cope with the seasonal drought and waterlogged soils.
- Waxy and hairy coating on the plants helps them to survive the cold and the windy conditions. This waxy coating helps to retain heat and moisture and allow the seeds to reproduce even in the extreme cold conditions.
- The small leaves of the plants retain moisture. The root system of these plants is shallow as only the upper top layer defrosts in the cold environments and below this layer is the layer of permafrost.
- Lichens and moss can remain alive only with little nutrition and moisture and can survive on the bare rocks.
- Plants have protection against low light conditions too which means that that plants don’t die in the winters. They have a long life cycles even with the short growing seasons. Photosynthesis in these plants start immediately when the sunlight is available and strong. Example – Arctic poppy have cup shaped flowers which face the sun to capture as much light and heat as possible.
Some examples of plant adaptations are:
- Lichen– It does not soil to grow and can survive in very cold environments even beneath the layer of snow. The growth of this is very slow.
- Cushion plants – These are compact and low growing plants. The small stature of these plants help them to survive in cold and windy environments. These have ability to catch airborne dust and use it as nutrition.
- Cotton grass – Small and lightweight seeds of this grass can be easily dispersed by the wind. The short height protect it from cold and thin leaves prevent transpiration. The seeds dispersed breaks its dormancy as soon as the temperature increases.
Adaptations in Animals
- Camouflage – The animals like polar bear, arctic fox etc has white fur which help them merge with the color of the snow and help them hiding in the snow.
- Thick layer of fur – The thick layer of fur in some animals protect them from the extreme cold conditions
- Exercise – Some animals do swimming as an exercise to keep them warm.
- Slow motion – These animals move slow and rest often to avoid overheating.
- Strong smell – They have very sharp olfactory senses which helps them to spot their prey.
- Closed nostrils – Some animals can also remain underwater and close their nostril to avoid water getting inside their body for a long time.
- Unity – Some animals like penguins show social characters and huddle together to keep each other warm.
Note – While animals can adapt to the extreme climates, birds do not adapt and migrate to other places when it gets too cold and come back when the temperature is warm enough for them to stay.