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0 <br />(1) <br />Nmin = (t's = ) + Wk) 2 <br />where: <br />N min = the minimum number of observations needed, <br />t = 1.833 (the t -table value for a two - tailed t -test with <br />(10 -1) degrees of freedom at the 90t confidence level), <br />s = the sample variance, <br />d = .1 (level of precision for estimate of the mean to be <br />within 10% of the actual mean), and, <br />R = sample mean. <br />0 <br />Initially, ten transects will be randomly located and <br />oriented in each area. Transect locations or orientations that <br />result in overlap of previous transects or the sampling area <br />boundary will be randomly redirected prior to the point of overlap. <br />Data from the ten initial transects will be used to determine <br />sample size adequacy. If sample size adequacy is reached with ten <br />transects, no further transects will be monitored. <br />Ground cover will be evaluated along each transect by sampling <br />two points (1.0 -meter apart) at 1.0 -m intervals. Cover will be <br />classified as vegetation, litter, or rock. Lack of cover will be <br />classified as bare soil. Vegetation will be further classified by <br />species. Each transect will consist of 50 point samples. <br />Using a Cover -Point Optical Point Projection Device (Model 2), <br />each point sample will be determined by projecting the ocular sight <br />vertically downward to the sample location on the transect and <br />recording all "hits" on vegetation. The "hits" will be used to <br />estimate total vegetative cover for each transect according to <br />equation 2. <br />(2) <br />°s Total Veg. Cover = No. Hits on Vegetation x 100 <br />Total Hits of Points <br />The mean vegetative cover for each of the two areas is <br />the mean value for the ten transects. <br />The composition of plant species in each area will also <br />be evaluated using the data acquired from the vegetative cover <br />transects. Data from the transects will be used in equation 3 to <br />• determine the relative cover of each species detected: <br />2.05-51 (a) - (revised 8/29/97) - - <br />I � `11 <br />g19y <br />