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7 <br />described four types of meanders -- free, restricted, confined, and fixed -- and two of <br />these types occur on the Green River. This classification is not appropriate for those <br />narrow valleys where the channel is greatly affected by coarse debris supplied from <br />tributaries, however. Schmidt and Rubin (1995) termed these narrow and steep <br />segments as "canyons with abundant debris fans" and described the characteristics of <br />the fan-eddy complexes that are typical within them. <br />Direct Measurements of Bar Topography and Shoreline Complexity <br />Field topographic surveys were made at one study site in each of the three channel <br />planform types. Bar topography was surveyed using an electronic distance meter, and <br />elevations were tied to fixed datums. Shoreline complexity indices were computed from <br />these data by measuring the length of each topographic contour and dividing this value by <br />the distance along the channel centerline. <br />Determination of Nursery Habitat Availability from Air Photos <br />Shor-line complexity throughout the study area was estimated from aerial <br />photographs of the Green River taken at low discharge. These photos are of about 1:2000 <br />scale, except in deep canyons where the scale is somewhat smaller. These photos were <br />taken in late summer 1963, but the exact date can not be determined because markings <br />are not evident on these photos; the photos were found discarded in a government agency <br />warehouse. The approximate date of the photos was estimated by the status of bridge <br />construction at Ouray. Mean daily discharge between mid-August and mid-September <br />1963 near Jensen and near Ouray was between 9.6 and 27.8 m3s' and between 22.9 and <br />56.3 m's-', respectively. These discharges are less than 0.1 times the 2-yr recurrence <br />annual maximum flood which is approximately the same as the bankfull discharge. The <br />photos were taken over a period of 2 dys, and no significant tributary inflows are <br />detectable on the photos.