Wednesday, June 9, 2010
Layers of peat at a depth of 10 metres below the surface in large parts of the provinces of South Holland and Utrecht have caused more than three metres of subsidence over the past 2,000 years.
The speed at which the ground is sinking depends on the thickness of the peat and the weight of the sand and clay layers above it. The process is also accelerated by the lowering of groundwater levels caused by agriculture.
The study shows that the settling of peat increases the risk of flooding and of subsiding dykes. "Taken together with the rise in sea levels, this is dangerous for the Netherlands," notes Ms Van Asselen.
The computer model she has developed enables estimates of future subsidence to be made. Time to buy some extra wooden shoes and sail away?.)