Guidance Heathland and fens
Index section Heathland and fens
- Description of the heathland and fen ecosystem
- Heathland: area
- Heathland: breeding birds, butterflies and reptiles
- Subsection: Guidance Heathland and fens: habitat fragmentation
- Subsection: Guidance Heathland and fens: water draw down and acidification
- Subsection: Guidance Heathland and fens: encroachment of grasses and trees
Introduction
Heathland is a vegetation dominated by subshrubs, particularly heather, bell heather, crowberry and bilberry. Trees and shrubs are sparse or absent. The Dutch heathlands are on higher-lying sandy soils and in the coastal dunes.
Whereas dune heathland is a natural phenomenon, the heathlands on sandy soils were created from forest by human activity. For centuries the heathland was an essential component of a particular farming system. The farmers grazed their sheep on the heathland. In winter, they kept their livestock in sheds that were bedded with heather sods cut from the heathland. In spring, the dung-impregnated sods were spread on the arable fields, as fertiliser.
Once artificial fertiliser became available, large areas of heathland were converted to arable land and much heathland was afforested with conifers. This greatly reduced the area of heathland. The heathland remaining today is primarily important for recreation and nature conservation.
Much of the present-day heathland and raised bog is in small, scattered areas. This fragmentation has adverse effects on certain animal species, such as the common viper.
The area of wet heathland is much smaller than that of dry heathland. The heathland fens are at risk from the effects of water draw-down and eutrophication. This is why there has been massive degradation of the characteristic vegetations. Fortunately, measures can be taken to restore them.
As a result of the encroachment of grass and trees and also the effects of water draw-down, the numbers of birds and butterflies have plummeted since 1950. This trend has continued in the last 10 years. The species that have declined most are those of the open heathland, such as the wheatear. The characteristic butterflies of wet and dry heathland and raised bog are also declining. Heathland reptiles are faring better: the common viper is not suffering from the grass encroachment.
An important part of the vegetation on the active dunes consists of lichens that are at risk from encroaching grasses. The invasion of grass and trees is also deleterious for the tawny pipit, a species that mostly occurs in active dune areas.
