What were these lost lands like?
The mapping by The University of Birmingham allows us to envisage for the
first time the lost lands beyond the modern coastline of Britain - a landscape of low-lying
hills, ever-shifting river courses, floodplains, marshes and lakes. Environmental studies
conducted on intertidal sites provide additional detailed information on this landscape.
Changes in the climate had a major influence on the landscape and vegetation. As the ice
sheets retreated it is thought that these lower lying areas would initially have resembled
the treeless, grassy tundra of modern-day Siberia. As temperatures rose, the low-lying areas
were covered by wetland marsh, with pine and birch forests eventually becoming established
and widespread. Approximately 10,000 years ago Britain was covered by woodland up to a tree
line of 2,000 feet or more. Investigations at Bouldnor Cliff, Britain’s first underwater
Mesolithic site, 11m deep in the Solent off the Isle of Wight, have revealed an environment
that changed over this period; pine forests slowly replaced by oak and hazel and the formation
of brackish and tidal flats before total inundation. Professor Martin Bell has recorded
evidence for Mesolithic oak woodland existing approximately 7,800 years ago at the archaeological
site of Goldcliff East, on the Severn Estuary. This site now lies in the modern intertidal
zone but, around 7,500 years ago it was situated on the edge of a former bedrock island
that was surrounded first by forest, then by a changing wetland habitat of sometimes reed
swamp, fen woodland or saltmarsh with open sea at high tide. Pollen, insect and plant samples
taken from an area of the submerged forest demonstrate that the woodland had colonised a
once predominantly open landscape of reed swamp and sedge fen. As the coast of Wales receded
to roughly its current extent, the habitat of the coastal margins may have variously been
reed swamp, peat bog and woodland before becoming seashore, estuarine mud or rocky foreshore.