Two kinds of rainforest

The rainforest biome has two kinds of rainforest, tropical and temperate.

A temperate rainforest has:

©Getty Images

©Getty Images

  • An annual rainfall of over 140 cm,  less than that of tropical rainforests,  spread out all through the year;
  • Average temperatures that do not have extremes of cold and heat;
  • Fogs and mists are common;
  • Only about 30% of the sky can be seen, the rest is covered by the canopy. 

In Australia, a temperate rainforest has tree species that do not require fire for releasing seeds, as some Australian species do.  Seedlings must be able to germinate and grow in light filtering through from natural gaps in the canopy.

Temperate rainforests occur in only a few regions of the world, and are found near coastal areas  They are found along the Pacific coast of Canada and the USA, and in New Zealand, Tasmania, Chile, Ireland, Scotland and Norway.  

In Australia both tropical and temperate rainforests can be found.

Warm-temperate rainforests

Warm-temperate rainforest, Queensland, Australia. ©Getty Images

Warm-temperate rainforest, Queensland, Australia. ©Getty Images

Warm-temperate rainforests grow at higher altitudes than tropical rainforests.  Apart from the forest floor,  they have two layers, consisting of a fairly even canopy of trees and a lower layer of tree and ground ferns, though these are not plentiful. There are usually only 3 to 15 different tree species, with slender, even trunks, marked with circular patches of lichen. They do not have buttresses. 

Cool-temperate rainforests

A misty cool-temperate rainforest. ©Getty Images

A misty cool-temperate rainforest. ©Getty Images

Cool-temperate rainforests (also called moss forests) are found in high places, around 900 to 1500 metres, have a high rainfall and, as their name suggests, have cooler temperatures. When it is not raining, these rainforests are often misty.

Apart from the forest floor, there are two forest layers – the top layer is a canopy that is more or less even, reaching a height of about 20m. Trees do not have buttresses. Below the canopy there is a layer of thickly growing tree ferns and other ground ferns. The bases of the trees can be massive, and there are no large vines or many epiphytes, though there may be thin vines and some orchids.

Mosses and lichens are plentiful and grow thickly. The plant species are different in each country, for example in California, the giant redwood trees dominate, in other places, fir trees may dominate.

Ancient pencil pines, Tasmania. ©Getty Images

Ancient pencil pines, Tasmania. ©Getty Images

In Australia the largest areas of cool temperate rainforest are found in Tasmania, covering around 10% of the island state, and there are also some patches in Victoria. 

Tasmanian rainforest dates back over 60 million years. The most common tree in Australian cool temperate rainforests is the southern or Antarctic beech, which is evidence that Australia was part of the southern supercontinent, Gondwanaland, more than 130 million years ago.  

The main trees include myrtle, leatherwood, celery-top pine, sassafras, Huon pine (some of which are over 2,000 years old), pencil pine, King Billy pine or deciduous beech. These are ancient species of trees that evolved from trees growing in Gondwanaland, before the eucalypts and acacias evolved.

 Animals of the cool temperate rainforests of Australia include ringtail possums, pademelons, spotted tailed quolls, and the dusky antechinus, tree frogs, rosellas and black currawongs.  Tasmanian rainforest contains some of the most ancient invertebrates such the large land snail, Macleay's swallowtail butterfly, freshwater crayfish and the peripatus, or velvet worm.

Warm-temperate rainforest, Australia. ©Getty Images

Warm-temperate rainforest, Australia. ©Getty Images

Australia's warm-temperate rainforests  are on the east coast of New South Wales into Queensland. The most southern are are small patches in Victoria.  Red cedars and coachwoods are dominant trees, and sassafras, blue gum, blackbutt, casuarina and lilly pilly. There are few vines, but native hibiscus, pittosporum and tree ferns are among the plants, and there are many ground ferns and lichens.

Animals in the rainforest

A lyrebird male dancing to impress a female. ©Getty Images

A lyrebird male dancing to impress a female. ©Getty Images

Birds are plentiful, including honeyeaters, lyrebirds, red-tailed black cockatoos, fairy-wrens and frogmouths. There are many reptiles and frogs, lizards and butterflies. Animals include the dingo, a number of wallaby and small possum species, bandicoots, quolls and bats.

There are different animals in temperate rainforests of different countries.  Most of the animals of the temperate rainforests live on or near the ground, where there is more food and shelter.

Threats to rainforests

Human activities threaten rainforests. It takes temperate rainforests several hundred years to mature, and so fires pose a lasting danger. Another threat is clearing of rainforests to use the land for farming, plantations, dams or mining. Rainforest timber is valued for its beauty and usefulness. However, rainforest trees grow slowly so it is not economical to grow them in plantations for timber.

 In Australia, both temperate and tropical rainforests are threatened.  Currently in Australia, Huon and King Billy pine cannot be exported.


Read about Australia's warm-temperate rainforests and see wonderful photos:

http://www.steveparish-natureconnect.com.au/nature-centre/warm-temperate-rainforest/

Read about Tasmania's ancient cool-temperate rainforests:

http://www.parks.tas.gov.au/?base=3207

Read more about temperate rainforests :

http://www.rainforest-facts.com/temperate-rainforests.html

Read the kidcyber page:

Tropical rainforests

Read kidcyber pages about other biomes: