DISTURBANCE AND RIVERINE BENTHIC COMMUNITIES: WHAT HAS IT CONTRIBUTED TO GENERAL ECOLOGICAL THEORY?

Disturbance from floods and/or low flows is a pervading force in almost all benthic riverine communities around the world. As such the study of disturbance effects on benthic communities has been a dominant theme of research in benthic river ecology. Many of these studies have been phenomenological or have evaluated hypotheses developed in other areas of ecology. These studies have provided considerable weight to move the common view of ecological communities in general as deterministically structured, to one where stochastic disturbances can be the dominant structuring force in many communities. Benthic river studies investigating the link between disturbance and diversity have generally failed to find support for single variable hypotheses, such as the intermediate disturbance hypothesis, from other areas of ecology, however, river ecologists have been among the first to embrace multivariate models of diversity. The highly mobile, larval life history stage of many riverine invertebrates makes many of the hypotheses generated in general ecology inappropriate for benthic river communities; however, the recently popularized neutral models may prove to be good descriptors of these communities. Food web structure studies indicate riverine webs respond differently to disturbance from the way predicted by ecological theory. The contribution of studies of disturbance in benthic ecology to general ecology has to date been rather limited with some notable exceptions. However, the ubiquity of floods in rivers worldwide offers fertile ground for future contributions that could substantially advance this area of ecology. Benthic river ecologists need to resist the temptation to simply show general ecological models often do not work in streams, and need to develop their own models, which in turn may feed back to wider ecology. Copyright (C) 2009 John Wiley & Sons, Ltd.