Interdependence:
● Plant cover is low
○ Cold climate causes plants to grow/decompose slowly
○ Soil is relatively thin/low in nutrients
■ In summer there is greater plant cover
● Plants absorb heat from the sun
● Prevent permafrost from thawing
● Permafrost provides water for plants
○ Birds and small mammals use moss to line their nests to keep warm
● Herbivores rely on plants (eg/ mosses) to survive
○ Must migrate to areas where plants are able to grow → carnivores follow herbivores
● Changing components/parts of the ecosystem can have knock-on effects
○ Vehicles damaging plant cover cause permafrost to melt
○ Melting permafrost can flood land
■ Prevents plants from growing
■ Releases trapped greenhouse gases (methane)
○ Increased greenhouse gases leads to global warming → affects cold environments further
Animal adaptations:
● Animals are well-insulated
○ Often have a thick fur coat, layer of blubber or double layer of feathers
■ Reduces amount of energy needed to keep warm
○ Larger bodies, shorter arms, legs and tails → small SA : V ratio
■ Helps retain heat and reduce heat loss
● Hibernate to conserve energy in the winter
● Migrate to warmer climates during harsh winter months
○ Tundra has a low animal biodiversity as most birds/mammals migrate during winter months
● Animals have white coats in winter for camouflage
● Example of well-adapted animal: Caribou
○ Have 2 layers of fur
○ Migrate to escape harsh winter
○ Have a compact, stocky body with short tail and ears
○ Have split hooves
■ Can spread apart to bear more weight without sinking into snow
■ Act as paddles when swimming
○ Graze like other herbivores in summer , eat lichen in the winter
■ Hooves developed to dig lichen deep under snow
■ Gut bacteria developed to help digest lichen
Plant adaptations:
● Plants become dormant to survive the harsh winters
○ Have adapted to growing season of 50 – 60 days
● Strong winds in North Pole due to high air pressure
● Plants have adapted to limit water lost through transpiration and to keep warm
○ Small and round-shaped to provide protection from the wind
○ Small leaves to limit moisture lost
○ Grow close together near ground level → plants trap pockets of warmer air
○ Have a waxy, hairy coating to retain heat and moisture
Plants have shallow roots due to layer of permafrost
○ Chills the ground and is a barrier to root growth
○ Reason as to why trees cannot grow in tundra → need long, deep roots
● Plants can tolerate extremely dry and wet conditions
○ Ground is very dry in the winter due to permafrost
○ As active layer of permafrost melts in summer , soil can become waterlogged
● Low insolation in tundra → light source is very weak
○ Most shrubs/plants are perennials (live for several years)
■ Photosynthesis can begin immediately → maximise growth
■ Plants do not need time to regrow leaves (already there)
● Example of well-adapted plant: Arctic moss
○ Shoots live 7 – 9 years , leaves live 4 years → long life/slow growth = perennial
○ Lots of leaves on the stem → more photosynthesis in short growing season
■ Stores nutrients when not growing → allows new leaves to be made quickly in next season
○ Can grow under water → protected from cold dry air
○ Short, have tiny leaves and don’t have wooden stems
■ Leaves are usually only one cell thick
■ Short nature allows them to grow near the ground → adapted to strong winds
○ Can reproduce by sending out spores