Reference water line

National selection of representative watercourses. Presentation of the type-specific reference state as a basis for the hydromorphological assessment within the meaning of the WFD and as a basis for work in the conception and planning of type-specific measures.典型河道的国家级遴选。阐释类型专属基准状态，该状态可作为符合《水框架指令》（Water Framework Directive）所界定的水形态学评估的依据，同时作为类型专属措施的构思与规划工作的基础。