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Harry Ranney <br />January 22, 2004 <br />Page 2 <br />J <br />Vegetative Ground Cover <br />Sampling for vegetative ground cover will be conducted in June of 2004. Vegetative ground cover <br />will be evaluated on the Dryland Reference Area and the two reclaimed area traits using 50-meter <br />point intercept transects. Two sampling points (one meter apart) on both sides of the transect will be <br />sampled at one meter intervals, resulting in 100 sample points per hansect. Each corresponding <br />sample point is determined by projection of the ocular sight (Cover-Point Optical Point Projection <br />Device, Model 2) vertically downward and physically recording all manner of"first hits". The "first <br />hits" will be recorded as rock, bare grotmd, litter, or live vegetation. Live vegetation will be fiuther <br />classified to genus and species. Vegetative ground cover on the reclaimed areas will be considered <br />successfitl if the sample mean is at least 90 percent of the cover sample mean measured on the <br />corresponding reference area. <br />The live vegetative "first hits" will be used to calculate total vegetative cover for each transect <br />according to Equation 1. <br />(1) <br />Percent Total vegetative Cover = Number ofHits on Vegetation <br />Total Number of Points <br />Fifteen transects will initially be evaluated on the Dryland Reference Area and both ofthe reclaimed <br />area sampling traits for success comparison and statistical evaluation. The Snedecor-Cochran sample <br />adequacy formula (Equation 2) will be used to determine that an adequate number of transects are <br />sampled. <br />(~) <br />t's' <br />(rlx) <br />Where: <br />N = required number of transects or quadrats <br />d = desired level of precision (0.1 the level ofprecision for estimate ofthe <br />Mean to be within 10% of the actual mean) <br />x = sample mean <br />sz = sample variance <br />t = the a = .10 t-table vahte for a single tailed t-test with n-1 degrees of <br />freedom <br />• <br />