Determining the ecohydrological character of aquatic refugia in a dryland river system: the importance of temporal scale

Aquatic refugia are important features of riverine landscapes; providing habitat for biota during extremes and facilitating the recovery of biota from disturbance. The persistence and quality of aquatic refugia is intricately linked to the hydrological regime of their parent rivers. Knowledge of the influence of hydrology on refugia is essential for understanding their role in the functioning of riverine ecosystems. A hierarchical framework is used to investigate the hydrological character of refugial waterholes in a dryland river system at multiple temporal scales. The study demonstrates that temporal variability is matched by a high level of spatial variability in hydrological character and that spatial patterns in hydrological character varied according to the temporal scale at which hydrological characterisation was made. The findings of this study have important implications for dryland river ecosystems because of the fundamental importance of hydrology as a driver of riverine ecosystems.