WSP01460 - Laserfiche WebLink

Home Browse Search

(:"1 ~, ~ ~ r.'fj ~ Table 3.2. The detailed habitat types and the eight general categories used by researchers on the San Juan River Source: Bliesner and Lamarra 2000). Backwater Habitats Low-Velocity Habitats Other Habitats Backwater Backwater pool Embayment Debris pool Eddy Edge pool Pool Riffle eddy Rootwad pool Abandoned channel (dry) Boulders Cobble bar Typically an indentation of channel below an obstruction, water depth from <10 em to > 1.5 m, no perceptible flow, substrate typically silt or sand and silt. Occurs at mouths of dry secondary channels and tributaries, lower ends of eddy return channels, mouths of dry scour channels, and behind debris. Same as backwater except maximum depth >2 m. Similar to backwater but formed when water pools up at upstream end of secondary channel with little or no outflow into the secondary channel. Same as pool, except organic debris such as tree limbs or tumbleweeds in pool. Same as pool, except water flow usually evident (but slow) and direction typically opposite that of channel or circular. Same as pool, except along shore and typically present downstream of shoreline or instream obstructions. Area within channel where flow is not perceptible or barely so; water depth usually ~30 em; substrate is silt, sand, or silt over gravel, cobble, or rubble. Area adjacent to riffle where water velocity slow to moderate (5-10 em/see) and flow often circular. Substrate sand, gravel, or cobble. Depths usually about same as adjacent riffle or slightly deeper. Pool formed by areas of rootwad piles; typically found along river margin. Non-flowing secondary channel. Large (>30 em diameter) rocks in channel. Bar of exposed substrate consisting primarily of cobble, usually found within the river channel but may be located along river bank, Irrigation return Channel where water is returning to river after application to agricultural fields, Island Isolated pool Rootwad pile Sand bar Tributary Dry, typically vegetated area of land surrounded by water and located within the river channel. Small body of water in a depression, old backwater, or side channel that is isolated from the main channel as a result of receding flows, Woody debris located within river channel. Same as cobble bar but composed primarily of sand or silt substrate. Tributary channel with flowing water entering main river channel. September 2000 Program Evaluation Report 3-17