Year Established: 2016 Start Date: 2016-03-01 End Date: 2017-02-28
Total Federal Funds: $4,912 Total Non-Federal Funds: $2,456
Principal Investigators: Ellen Wohl
Abstract: Beaver (Castor canadensis) alter channel and valley morphology by building dams that trap sediment, organic carbon, and nutrients and raise the riparian water table. Frequent overbank flow in beaver meadows deposits fine sediment on the valley surface and leads to a complex valley-floor with multiple channels and high biodiversity known as a beaver meadow. The intricate morphology in beaver meadows retains water, and increased residence time improves downstream water quality by allowing nutrient uptake and settling of fine sediments and pollutants. Human removal of beaver has simplified stream hydrology and geomorphology in mountain streams. Although much is known about how beaver initially alter valleys, few studies have investigated hydrologic changes after beaver disappear, especially in valleys where the dams were allowed to naturally degrade. Additionally, most beaver meadow geomorphic, hydrologic and biogeochemical studies have focused on single beaver ponds. We propose to quantify the changes in water, sediment and organic carbon dynamics in active and abandoned beaver meadows of various ages and sizes the Colorado Front Range. We will investigate the effects of beaver meadows on catchment-scale retention processes, and quantify losses of retention as abandoned beaver meadows simplify through time. Our study has implications for assessing the restoration potential of beaver meadows as retention features at the catchment scale. Given population projections and predictions of increased climate variability, retention of water and carbon (along with other nutrients) will become increasingly important in the Colorado Front Range as water managers try to meet the water needs of downstream communities.