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<br />results in the average morphologic characteristics of a channel (Dunne and <br /> <br />Leopold (1978). <br /> <br />STATISTICAL TESTING <br /> <br />Tests for significant differences between means of the seven parameters were <br /> <br />used to indicate if physical properties of aquatic habitats varied between strata. These <br /> <br />tests would be used as justification on whether or not to combine similar strata into larger <br /> <br />groups or management units or not. Each variable was tested at three flow levels; 80, 150 <br /> <br /> <br />and 300 cfs. Eighty cfs represented minimum flows that infrequently have occurred <br /> <br /> <br />(<25%), 150 cfs represent the minimum flow that commonly occurs (<50%), and 300 cfs <br /> <br /> <br />represents median flows that typically occur during the base flow period. A <br /> <br /> <br />heteroscedatic t-test was used to compare means of each of the seven variables between <br /> <br /> <br />strata. The null hypothesis was that the means of adjacent strata were equal and the test <br /> <br />also assumed unequal variances. This test was performed by the excel spreadsheet. <br /> <br />INFLECTION POINT DETERMINATION <br /> <br />To understand how channel morphology influences habitat characteristics, the <br /> <br />values for each ofthe seven variables were plotted for a range of flows between 1 to 300 <br /> <br />cfs (300 cfs representing the median flow during the base flow period). The "inflection <br /> <br />point" of each curve was identified for seven variables at all cross sections by fitting a <br /> <br />line to the x and y coordinates and then selecting the largest residual (greatest difference <br /> <br />between the curve and the line). Inflection points were grouped by habitat type, riffle, <br /> <br />run or pool and by parameter. Inflection point means were compared between variables <br /> <br />and between habitats for differences. <br /> <br />13 <br />