SHR Spatial Scales
Different approaches to rehabilitating regulated rivers exist. All may be organized according to their spatial and temporal scales.
- Quick local fixes help now to prevent population crashes, but are not sustainable alone over decades and beyond.
- System changes may some day reap benefits- assuming the underlying science is correct, though most of it remains untested even now- but these broader efforts will not save collapsing populations and food webs to get to that day.
- Here we focus on the scales relevant to rregulated river reaches downstream of large dams on major rivers with few downstream tributaries.
Hydraulic Unit Microhabitat
0.1 - 10 channel widths
days to years
Provide higher quality habitat for existing populations right now
Geomorphic Unit Mesohabitat
~ 1-10 channel widths
years to decades
Provide greater quantity and diversity of habitats to (i) serve multiple life stages and increase population size and (ii) serve a community of species to protect biodiversity
100-1000 channel widths
decades to centuries
Provide a mechanism for self-sustainability of the river system into the future