Over a length of 315 km 284 sampling sites are scattered usually 1 km in
a distance from each other. Because of variable width sampling plot size
differs by a constant length of 50 m. All vascular plants from waterline
to neighbouring areas were recorded. Plants occurrence in sampling sites
are represented by frequencies in percent or with Roman numerals according
to the classification of plant sociology. In addition random sampling along
the river banks was carried out to provide a complete record of species
present.
Distribution of sampling sites within the Oker
system
