The River Wave Concept: Integrating River Ecosystem Models

We introduce the river wave concept: a simple, holistic model that unifies river ecosystem concepts. The river wave concept proposes that river flow can be conceptualized as a series of waves varying in shape, amplitude, wavelength, and frequency, traveling longitudinally and laterally; the position on the wave determines the source of organic production or inputs and the storage, transformation, and transport of material and energy; and existing concepts explain ecosystem phenomena at different positions on the river wave. The river wave concept hypothesizes that, at the troughs of waves, local autochthonous and allochthonous inputs predominate; on the ascending or descending limbs of waves, upstream allochthonous inputs and longitudinal transport of material and energy predominate; and as waves rise to crests, allochthonous inputs of material and energy and autochthonous production from the floodplain increase. We describe how river waves interact with their environment and the relevance for biota.