Ecological quality classes of river hydromorphology in Poland.

摘要

This work presents rules and results of classifications of hydromorphological status of watercourses used presently in Europe. The Water Framework Directive introduced an obligation to monitor hydromorphological elements of rivers, which include hydrological regime, river continuity and bed morphology. European standards require somewhat different quality indicators and the way of their assessment for such investigations. Classification of status and ecological potential shall include categories and types of rivers, however, the methods existing so far do not provide such a distinction. Assessment of much differentiated features and attributes, as well as the requirement of presenting the outcome in EQR form, within limits from zero to one, cause that all the studied parameters, which are very diverse, must be conveyed to numerical form. The MHR method takes into account the above conditions and proposes a classification which includes limit values for five classes of status and four classes of ecological potential. It assumes limit values of classes lowering from natural watercourses through heavily modified to artificial.