Resizing a River: A Downscaled, Seasonal Flow Regime Promotes Riparian Restoration

摘要: While riverine organisms are adapted to the natural flow regime, it is impractical fully restore flows along most regulated rivers. We propose an alternative with delivery of downscaled regimes that provide seasonal patterns essential for aquatic and riparian ecosystems. The Bridge River in British Columbia provided a novel case study as regime commenced 2000 reach had generally experienced no prior half-century. experimental delivered mean discharge about 3 m3/s, versus pre-dam 100 pattern mimicked snowmelt-dominated pattern. To assess environmental response, we investigated black cottonwoods, Populus trichocarpa, dominant trees, pre-flow post-flow intervals, using tree ring interpretation growth analyses age determination. Sparse mature trees established 1948 damming did not show significant changes pre- intervals. In contrast, younger closer river decade displayed increases by 2002, juveniles after demonstrated faster initial than before 2000. Further, bands cottonwood saplings resulted from seedling recruitment new fringe, particularly 2003, 2004, years gradual recession. These responses demonstrate downscaled, benefit, thereby restoring some function resulting resized flanked narrow reproducing bands.