Description of swamps ecosystem

Introduction

Marshes, bogs and swamps are waterlogged to wet areas consisting of open water, terrestrialising vegetation, reedbeds, thickets and swamp woodland. The Netherlands has many such areas as it is on the delta formed by the Rijn and the Maas. Much of the pristine marshes, bogs and swamps have been drained and converted to farmland; the remainder have become areas of lakes, because water has filled the holes left after large-scale peat extraction. Bogs come about when the vegetation closes over the open water and terrestrialisation begins. The natural vegetation succession will ultimately result in swamp woodland or boggy heathland.

In addition to the extensive bogs there are also waterlogged zones alongside lakes, pools and other water bodies. Those on peat are called bogs. Those on clay are marshes. They are dealt with in this section. The raised bogs and boggy heathland are dealt with in the section on heathland and fens. Swamp woodland is included in woodland and forests, and waterlogged impoverished grassland has been assigned to the semi-natural grasslands (see the sections on forest and woodland, and on grassland and cultivated land). Saltmarshes are dealt with in the section on the Waddenzee and Zeeland delta.

The use of marshes, bogs and swamps

A large area of the Dutch marches, bogs and swamps have been exploited for agricultural land. Another part has been converted into open waters because of large-scale exploitation for peat. However, still a substantial area of marches, bogs and swamps has been left over.

Marshes, bogs and swamps have long been exploited for reed, rushes and withies. To guarantee the supply, people planted and maintained reeds, rushes and willows. Nowadays these crops are of little economic significance and the main value of marshes, bogs and swamps is for recreation and nature conservation.

Significance of marshes, bogs and swamps

Marches, bogs and swamps contain many rare plant communities, especially in the early stages of terrestrialisation and in sphagnum-reed vegetation. Many of the plant species found in Dutch marshes, bogs and swamps are endangered species that are also rare in Europe. A large proportion of the Western European population of certain breeding birds also occurs in these habitats, such as bluethroat, cormorant and spoonbill. There is a subspecies of the large copper butterfly that is unique to the Netherlands.

Many Dutch marshes, bogs and swamps are too small for many species to be able to survive in them for a long period, particularly if these areas are very isolated. It is not only habitat fragmentation that puts the flora and fauna at risk: a further problem is that the vegetation is not rejuvenating and shrubs and trees are encroaching. Other negative factors are intensive mowing regimes and water recreation. Pleasure boats can be damaging because of the wash they create and because reed is damaged when they are moored.