Dunwich Heath?

Question

Long shore drift
what lives there
what grows there
erosion rates
maps
cost of maintaining the heath
how much heathland is there in the world
what perctntage of the wortld is heathland

Answer 1

The coastal cliffs at Dunwich are made up of soft Tertiary and Pleistocene clays and sands easily eroded by the sea.

Stretching for about a mile down the coast, Dunwich cliffs are fronted by a shingle beach (frequently recharged) which provides some protection from sea erosion, but the sea is remarkably close to the cliff and the slightest storm waves on a high tide inevitably result in more undermining of the fragile and loosely held together materials of the cliff.

Two types of erosion affect the cliffs of Dunwich; soil creep and gulley erosion.

Soil creep - an almost imperceptible movement of individual particles down a slope over a long period of time.

The yellow sand particles in the cliff swell when it rains, lifting them at right angles to the slope direction. When dried out, they shrink again, but the influence of gravity pulls the particles vertically down. Whilst soil creep cannot be observed, its effects can often be observed; a few years ago bones were seen sticking out of the edge of the cliff, presumably from a grave in one of the church graveyards. The sandy soil forms terracettes (or lobes) at the base of the slope, where it has begun to pile up.

map is on page 20 http://www.suffolkcoastandheaths.org/uploads/SC&H%20Management%20Strategy.pdf

Gulley erosion – deep V shaped drops in the cliff face with a fan-shaped scree slope below.