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Table 2 continued. <br />Total DTE <br />Relative DTE <br />Habitat-Bank <br />Run-Upper <br />er <br />Riffl <br />-Up 117.7 <br />127 <br />9 2.004 <br />344 <br />2 <br />e <br />p <br />P . <br />S . <br />S <br />Run-Lower 119.5 1.542 <br />Riffle-Lower 130.9 1.714 <br />P S S <br />Run-Upper 117.7 2.004 <br />Run-Lower 119.5 1.542 <br />P NS S <br />Riffle-Upper 127.9 2.344 <br />Riffle-Lower 130.9 1.714 <br />P NS S <br />one on the second and the other on the third sampling dates; an increase in DTE from the one <br />sampling date to the next was significant (P < 0.05). <br />Base flow. Through the base-flow period of both years, DTE was fairly constant. In fact, <br />in most cases it was essentially the same as during the third runoff sampling date. There <br />appeared to be a trend of increasing DTE during the base-flow period in riffles of Stratum 9 <br />in both years and in Stratum 8 in 1996 (Fig. 8), but differences among dates were not <br />significant. In riffles of Stratum 9, there was a large drop in DTE sometime between the last <br />base-flow date in 1996 and the first runoff date in 1997. This phenomenon did not occur in <br />riffles of Stratum 8 or in runs of either strata. <br />Relative Depth-to-Embeddedness <br />Depth-to-embeddedness, measured in number of free rocks (relative DTE), ranged from 1.1 <br />to 4.3 median rock widths. The overall adjusted mean was 1.9 rock widths in both 1996 and <br />1997 (Table 1). Again, DTE was slightly higher in Stratum 9 than in Stratum 8, and higher in <br />riffles than in runs. Relative DTE was somewhat higher in upper-bank locations than in <br />lower-bank locations -- the reverse of total DTE. This makes sense because rock sizes, <br />which effect relative DTE but not total DTE, were smaller at upper bank sites. Also, the <br />greater variation in relative DTE among sites (compared with total DTE) was due to the <br />variation in rock size. In general, those sites with the lowest number of free rocks were those <br />with the largest rocks; those with the highest number were those with the smallest rocks. For <br />instance, at riffle No. 2 in reach 8-B, there was a mean of only 1.2 free rocks in 1997, yet <br />mean total DTE was fairly high (about 130 mm). Also, the site with the highest number of <br />free rocks was riffle No. 1-B in reach 9-B (the bar dissected by small channels during <br />20