Discrete vs. continuum approaches to the assessment of the ecological status in Iberian rivers, does the method matter?

▸ Objective evaluations of ecological status depend on the capacity to define reference condition. ▸ Type-specific approaches define reference conditions for homogenous types or classes. ▸ If classes do not portray distinctive assemblages the risk of misevaluating condition is high. ▸ Continuous approach without classes should be used if strong classifications cannot be obtained.