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2.04.10 Vegetation Information <br />Positive coordinates were produced by a random number generator. The exact <br />sample point was then paced off by the field ecologist. <br />COLLECTION AND ANALYSIS OF COVER DATA <br />Cover was estimated using a point - intercept method along randomly located <br />and oriented transects (Mueller- Dombois and Ellenberg 1974). Twenty points were <br />sampled along the 50 meter length transects. Paired points were sampled at each 5 <br />meter interval of the transect. Each paired point was 0.75 meter from the transect and <br />perpendicular to the transect. <br />The sighting device was mounted on an adjustable tripod to facilitate vertical <br />orientation and point stabilization. Fine cross hairs were used in the sighting device to <br />provide optimum point definition. At each sample point, the sighting device was first <br />directed vertically upward, then vertically downward. If a tree and/or shrub was <br />intercepted a second or third hit was taken. The first hit along a vertical line was <br />recorded as vegetation (by species), rock, litter, or soil. Vegetation intercepted below <br />tree and shrub first hits was recorded as a second or third hit. Only first hits were used <br />in calculating percent cover. <br />Sample adequacy requirements for affected area cover data were calculated <br />using the OSM formula <br />S2 T2 <br />Nmin _ (—d XRT <br />where Nmin = the minimum adequate number of cover transects <br />s2 = sample variance <br />t2 = a designated t- statistic (0.84 for a one - tailed test with 80% <br />confidence) <br />d = desired limits of detection (0.1 or 10%) <br />x = sample mean <br />PR -02 2.04-53 10/12 <br />