A River Wave framework to unify river ecosystem concepts and predict ecological change

Abstract The River Wave Concept is a theoretical interpretation of river ecosystem processes that links flow to multiple river ecosystem concepts and contextualizes how a river functions with or without anthropogenic impacts. Here we propose a framework that can map the River Wave Concept to ecosystem concepts and wave metrics using widely available flow data from gauging station networks. The framework can produce a three-dimensional River Wave visualization, a time series of ecosystem process changes over time and wave metrics that can be related to organism patterns across space. Our case study contrasted Sweden’s fragmented rivers with modelled free-flowing conditions and found that the observed fragmented rivers may favour specific fish life history strategies, that ecosystem functioning has shifted towards more baseflow-dominated flow compared with free-flowing rivers and that restoring all rivers to free-flowing conditions would result in more similar rivers nationally. Our study highlights how river theory can help to identify river ecosystem change and provide data to inform new analyses, which are critical for managing impacts on rivers.