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-2s- <br /> <br />VEGETATION TYPE DESCRIPTIONS <br />The following discussion provides general descriptions of each vegetation <br />type surveyed on the study area using previously presented data. To <br />assist in the evaluation of species diversity for each vegetation coRmunity, <br />Shannon-Weiner diversity indices are presented in Table 7. The basis for <br />much of the vegetation type description is cover and production data. <br />These data were evaluated for sampling adequacy using the following formula: <br />N > 2 (s z)2 <br />mi n (d x) z <br />• <br />where : ' <br />Nmin = minumun number of cover quadrats, production exclosures or <br />tree density transects to achieve sampling adaZuacy. <br />x = sale mean of production per exclosure or percent basal Dover <br />per quadrat. <br />z = statistic (z = 1.28 for 90~ confidence level and 0.84 for 808 <br />confidence). <br />d = amount of reduction it is desired to detect (d = 0.1 for 90~ <br />confidence and 0.2 for 90~ confidence). <br />• <br />Substitution of the actual sample size for N ~ and solving for z provides <br />a means for determining the actual confidence limit achieved. <br />Consider the shrubland type with a mean production of 102.8 lbs/acre <br />with a standard deviation of 62.7 1bs/acre for 20 production samples. <br />Determination of min at the 808 confidence level is provided by <br />N > 2 (62.7 x 0.84)2 <br />min = (0.2 x 102.8) <br />N > 13 <br />nun = <br /> <br />