Floodplains in Europe have been influenced by humans for thousands of years. Civilizations often were established near rivers and frequently utilized floodplain resources for food (agriculture or hunting), power (wood or water mills), and shelter. As communities grew there was an increased need to control the flooding that naturally occurred in the floodplains with the use of dams, dikes, and ditching. These structures altered the hydrology which in turn has altered the forest composition in these areas. Furthermore, channel straightening has caused major hydrologic changes resulting from faster flow and increased groundwater depth. In some of the Danube watersheds, there has been an 80% decrease in first-order streams from 1780 to 1980.
In many areas, depth to groundwater has increased due to the 'drying' of the floodplains and this has driven shifts in the composition of vegetation communities. In particular, species such as Quercus robur, Fraxinus spp., and Ulmus spp. are becoming rarer due to the altered hydrology. Forestry practices have induced a further shift from natural systems to faster growing Populus clones in many of the floodplains across central Europe. However, reestablishment of the more traditional forest composition of uneven-aged oak, ash, and maple mixes has been achieved in some areas as recently as the past 50 years. Large portions of the forests remain monocultures of even-aged Acer or Fraxinus.
The Danube Delta represents one of the largest wetlands in Europe and is undergoing eutrophication as a result of increasing nutrient inputs, decreased riparian vegetation, and loss of the filtration function. One major difference between European floodplains and others worldwide is that increased flow and flooding often occurs in the spring as a result of snowmelt in high altitudes.
Was this article helpful?