The riparian community of north‐west European lowland streams

SUMMARY Riparian plant communities along lowland streams have been affected by man for the past 15000 years. During this period climatological changes have also taken place. The present situation in north‐west Europe is a result of these influences so that the choice of reference situations is necessarily arbitrary. Dominant abiotic factors that influence riparian vegetation are local hydrology and soil composition, and the pH, lime content and nutrient concentration of the feeding ground water. Riparian plant communities are described as phytosociological units. Depending on abiotic characteristics, sequences from spring to lower course and from the stream bank to the boundaries of the stream valley are reported. The Pruno‐Fraxinetum association is, and has been for thousands of years, one of the main riparian vegetation types of (lowland) streams. In many European countries, restoration projects are being performed or planned. One of the restoration measures is the planting of trees or shrubs along streams as buffer strips. A phytosociological approach, based on knowledge of the local hydrology and nutrient/ion availability, is better by far than the general practice of standard plantation. Such an approach requires research in advance, which increases the initial costs of projects, but can be expected to provide far better results in the long term, and ultimately save money.