Abstract
The hydromorphological reference conditions reflect the natural channel behaviour, which is extremely variable. As significant parameters of natural channel behaviour altitude, sinuosity and valley floor slope and stream order were determined on the basis of statistical analysis from prepared datasets of 4424 reaches of river water bodies.
Lithology of the study area was also taken into consideration. By combining the selected parameters 27 theoretical river types emerged that were validated by subsequent field survey and measurements at sites evenly distributed on the territory of the Czech Republic.
By correction 9 unmodified river types were determined and 2 types of probably modified and potentially modified reaches for which the nearest unmodified types were derived. This classification of river types is a basis of establishment of type specific hydromorphological reference conditions of streams on the territory of the Czech Republic that should serve for assessing the current status of streams and they also represent stream restoration target conditions.