bog burst

cliff falls

flood

mesolithic man

sea level

climate

storms

tephra

tsunami

vegetation

wind

 

Postglacial landscapes

Around 14 thousand years ago, the last ice sheet disappeared on Shetland to leave a barren, scoured terrain. As temperatures rose rapidly, pioneer plants arrived from the south and the low ground was soon carpeted with a rich herbaceous cover. For a bleak thousand years, there was a reversion to Ice Age conditions, only arctic species clung on and small glaciers probably reformed in north-facing hollows. With the melting of the last glaciers and the amelioration of climate at the start of the Holocene, around 10 thousand years ago, the pace of environmental change on Shetland slackened. The present interglacial has seen many slow changes in the landscape, with the development of soils, the succession of vegetation types and the rise of sea level drowning the major valleys. The steady pace of change has been interrupted by a sequence of natural disasters, including tsunami, heavy falls of volcanic ash and extreme storms. Man has been the main agent of landscape change in the last 6000 years, initially causing the loss of trees through felling and grazing by domestic animals but later affecting the entire landscape mosaic of soils, vegetation and peat development. In modern history, we have begun to physically reshape the land, opening quarries, reclaiming land, opening cuttings and creating building sites.