The East Anglia Region - Southern England - page 292

FIG 285. Woodwalton Fen.
The shrinking and wasting away of the Fenland soils has been mentioned above.
The Holme Post (Fig. 284) provides an impressive indication of the lowering of the
surface since the draining of Whittlesey Mere. This post was buried in 1848 in a ver-
tical shaft dug into the ground not far from the edge of the mere. When it was buried,
the base of the post was fixed into the underlying mudstone bedrock, and its top was
fixed level with the ground surface. The soil (much of it peaty) has shrunk 4 m in just
over 150 years (almost 3 cm/year), leaving the post projecting by that amount into the
air. It is interesting to see that the shrinkage was greatest in the early years, when the
ground was drying out particularly rapidly after the drainage of the mere in 1851.
At Woodwalton, Wicken and Lakenheath Fens, campaigns are being directed to-
wards preserving relicts of the early Fen wetland environment (Fig. 285). This has been
made more difficult by the recent drainage of the surrounding landscapes, but it now
looks as if the trend towards ever more efficient drainage is being reversed. The in-
creasing concern to protect threatened wildlife and provide people with recreational
space is encouraging long-term plans to re-flood and greatly extend the wetlands in
these preserved areas. The Fen wetland nature reserves are generally designed to be
maintained with a high water table, in contrast to the drained fens elsewhere. This fa-
vours a range of different ecological environments, controlled by the degree of drain-
age. Reed and sedge form at the edge of open water, followed by a scrub of willow and
alder as drainage becomes better.
FIG 286. 'Bog oak' at Wicken Fen.
The Peat Fens have often yielded large pieces of timber on ploughing, and heaps
of this material can sometimes be seen at the edges of fields (Fig. 286). This timber