Climate change and ice formation in streams
- effects on biodiversity and tools for proactive restoration
Climate models predict an increase in dynamic ice formation in northern streams due to increasingly fluctuating air temperature. Sub-surface ice (frazil and anchor ices), ice break-up and subsequent ice jams and flooding are expected to become more frequent. Winter already represents a bottleneck in the life-history of aquatic animal and plant communities. The ecological implications of increased dynamics during this critical period are uncertain, as many of the ongoing aquatic processes are still poorly understood, e.g. the physical factors governing ice formation or the effects of ice on organisms. Furthermore, anthropogenic exploitations may make rivers more sensitive to excessive ice formation. This project studies relationships between channel topography, hydraulics, ice abundance and distribution, and riparian and aquatic biodiversity in small streams. The study, which is a collaboration between ecologists and hydrologists, focuses on ice effects on plant and fish communities and uses hydraulic modeling to understand how temperature, stream morphology, discharge and water currents regulate ice abundance and distribution. The project will also identify the channel topography that is optimal for avoiding destructive ice formation and prepare recommendations for proactive restoration methods to sustain the biodiversity that is typical for boreal streams.