Heath (habitat)

From Wikipedia, the free encyclopedia

Heaths are habitats characterised by open, low growing woody vegetation, found on mainly infertile acidic soils. In the latter respect they are similar to moorland, but they differ in terms of climate – heathland is generally warmer and drier than moorland – and vegetation.

Heaths are widespread worldwide. Heaths form extensive and highly diverse communities in southern and south-western Australia where short fire regimes are a requirement for the maintenance of the heathlands. Equally diverse though less widespread heath communities occur in Southern Africa. Extensive heath communities can also be found in California, New Caledonia, central Chile and along the shores of the Mediterranean Sea. In addition to these extensive heath areas the vegetation type is also found in more scattered locations across all continents.

1 Characteristics
2 Anthropogenic heaths
3 See also
4 External links

[edit] Characteristics

Heathland is a lowland habitat, and is favoured where climatic conditions are typically warm and dry, particularly in summer, and soils acidic, of low fertility, and often sandy and very free-draining; bogs do occur where drainage is poor, but are usually only small in extent. Heaths are dominated by low shrubs, 0.2–2 m tall. In Europe heath vegetation is species poor and comprised primarily of heather (Calluna vulgaris), heath (Erica species) and gorse (Ulex species). It is noted for the brilliant colours when these species flower in late summer (see photo, left). In other parts of the world heathland vegetation is far more diverse, and heathlands of Australia and Southern Africa are second only to tropical rainforests in plant biodiversity.

Heathlands have a very typical associated bird fauna. In Europe these species include Montagu's Harrier, Eurasian Hobby, European Nightjar, Wood Lark, Tree Pipit, European Stonechat and Dartford Warbler; where there are scattered trees, Green Woodpecker is also characteristic. In Australia the heathland avian fauna is dominated by nectar feeding birds inclduling numerous species of honey-eaters as well as lorikeets. Some reptiles are also largely confined to healthland. In Europe these include the Sand Lizard and the Smooth Snake, and one amphibian, the Natterjack Toad. Australian heathlands are also home to the world's only nectar feeding terrestrial mammal: the Honey Possum. Heathlands are also an excellent habitat for insects including ants, moths, butterflies and wasps with many species being restricted entirely to it.

[edit] Anthropogenic heaths

Anthropogenic heaths habitats can be found worldwide in locations as diverse as northern and western Europe, the Americas, Australia, New Zealand, Madagascar and New Guinea where they have been created or expanded by centuries of human clearance of natural forest vegetation by grazing and burning. In recent years the conservation value of even these man-made heaths has become much more appreciated and consequently, most Heathlands are protected. However they are also threatened by forest growth as a result of the discontinuation of traditional farming techniques such as grazing and burning that kept the cultural landscapes intact. Some are also threatened by urban sprawl. Anthropiogenic heathlands are maintained artificially by a combination of grazing and periodic burning, or (rarely) mowing; if not so maintained, it is rapidly re-colonised by forest or woodland. Any re-colonising tree species will depend on the local seed source, and may not reflect the natural vegetation before the Heathland became established.

Although tiny by world standards one Europe's biggest heathlands is the Lüneburger Heide in northern Germany. Other notable heaths include large parts of the New Forest and the Breckland in southern and eastern England respectively, and the Veluwe in the Netherlands, and smaller areas in Dorset, Devon and Surrey in southern England.