Heath (habitat)
Heaths are
anthropogenic habitats found primarily in northern and western
Europe, where they have been created by thousands of years of
human clearance of natural
forest vegetation by grazing and
burning on mainly infertile
acidic soils. They subdivide into two broad categories depending on
climate, with true
heathland developing in warm, dry conditions, and
moorland developing in cooler, wetter conditions. As they have developed over a long period, a unique assemblage of
plants and
animals has adapted to thrive in these habitats. Until recently, modern techniques of
agriculture threatened some of this habitat, by
ploughing,
fertilising and planting with
arable crops, or in particular, conversion to commercial
forestry plantations. In recent years their value 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.
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Heathland at Woodbury Common, Devon (England). Purple flowers of Calluna vulgaris and yellow flowers of Ulex gallii |
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. It is dominated by low
shrubs, 0.2-2 m tall, particularly
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). The habitat is maintained artificially by a combination of grazing and periodic burning, or (rarely) mowing; if not so maintained, it is rapidly re-colonised by
forest, mainly of
pine (
Pinus species) and
Silver birch (
Betula pendula). Any re-colonising tree species will depend on the local seed source, and may not reflect the natural vegetation before the Heathland became established.
Heathlands have a very typical associated
bird fauna, notably
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. Some
reptiles are also largely confined to healthland, notably the
Sand Lizard and the
Smooth Snake, and one
amphibian, the
Natterjack Toad. It is also an excellent habitat for with many species being restricted entirely to it.
One of the 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. Heathland habitats are also found in parts of
Sweden,
Denmark,
France,
Spain and along the Norwegian coastline.
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Moorland in the Pennines (England); Coarse grasses and bracken tend to dominate especially in high rainfall areas. |
Upland
moorland habitats occur mainly in northern and western
Britain and
Ireland. Like heathland, they are often dominated by
heather, but differ from typical heathland in being colder and much wetter, often with extensive
bogs, giving rise to a different mix of associated fauna, such as
Red Grouse,
Hen Harrier,
Merlin,
Golden Plover,
Curlew,
Sky Lark,
Meadow Pipit,
Whinchat,
Ring Ouzel and
Twite. Reptiles are fewer due to the cooler conditions, with only the
Common Viper being frequent. When moorland is
overgrazed by excessive numbers of
sheep or
deer, most of the heather is lost, being replaced by coarse, unpalatable
grasses and
bracken, with a greatly reduced fauna.
|
Heather moorland, North Yorkshire Moors. In August these heather clad moors are spectacular. Mainly Calluna vulgaris here. |
Notable areas of upland moorland in Britain include
Bodmin Moor,
Dartmoor (see also
Dartmoor wildlife),
Exmoor, the
Dark Peak, the
North York Moors, the
Forest of Bowland, the
Lake District, the
Pennines,
Mid Wales, the
Southern Uplands of Scotland, the
Scottish Highlands and a very small pockets in the
Shropshire Hills and western
Herefordshire.
In more northerly latitudes, moorland is also found in lowland areas in the Scottish Highlands,
Iceland and
Norway; in the far north where trees do not grow naturally, moorland grades into natural
tundra.
*
Bolster heathSimilar landscapes are found in various parts of the world for example Western Tasmania (Australia) the spectacular
Kwongan in Western Australia, 'heathlands' in Eastern Australia. the heavy metal heaths of New Caledonia and
Fynbos in southern Africa.
*
The Countryside Agency information on types of open land
