It has been demonstrated in past studies that drainage area (Ada) and mean annual precipitation depth (Pmean) are significant independent variables for predicting bankfull channel geometry. Bankfull width (Wbf), a particularly useful measure of bankfull channel geometry, is used in hydrology, fluvial geomorphology and stream ecology applications. Since precipitation depth does not generally have a normal distribution over a basin it is reasonable to question whether or not Pmean is the best measure of precipitation across a basin. That is, perhaps the median precipitation depth (P50) or the mean annual precipitation depth at the basin outlet (Poutlet) is more representative of precipitation in a basin. The objective of the study is to see if Pmean, P50, or Poutlet is a significantly better measure of precipitation in a watershed. Along with Ada, each of these precipitation measures was used to develop relationships for predicting Wbf for basins located across the continental U.S. Using several goodness-of-fit statistics i.e., coefficient of determination(R2), Standard error of estimates(SEE) and Akaike Information Criterion(∆AIC), the relationships were compared to determine which one had the greatest predictive strength. Estimates of Pmean, P50, and Poutlet were derived from a precipitation model developed by PRISM. Results from this study tentatively indicate that all three measures of precipitation depth yield models for predicting Wbf that have comparable goodness-of-fit statistics.
| Identifer | oai:union.ndltd.org:siu.edu/oai:opensiuc.lib.siu.edu:theses-2731 |
| Date | 01 August 2015 |
| Creators | SHRESTHA, SURAJ |
| Publisher | OpenSIUC |
| Source Sets | Southern Illinois University Carbondale |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Theses |
Page generated in 0.0024 seconds