Year: 2015
Type: dissertation
Abstract: Field surveys in pool-riffle channel types within mainstem San Gregorio Creek show that \npool formation is driven in large part by flow obstructions that were exposed as a result \nof channel incision and widening, such as exposed bedrock outcrops and undercut banks hardened with exposed root systems. The depth, cover and complexity of these pools are generally much lower than the pools formed by Large Woody Debris in the study reaches. The pool spacing for the three sites is relatively high, averaging 3.5 pools per channel width which can be attributed in part to the low LWD frequency which averages 0.06 LWD pieces per meter across the three sites. When observed pool spacing and LWD frequency values in San Gregorio Creek are compared with those predicted using a regression equation based on a variety of Washington and southeast Alaskan stream channel types, the pool spacing is overestimated and LWD frequency is underestimated by a factor of roughly 3. This is due in part to the high proportion of often low quality pools formed by obstructions rather than LWD.
Author: Joseph Maxwell Issel
Language: English
Subfield: Earth-Surface Processes
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2127354169