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DATr1 ANALYSIS <br />A data base manageccent and analysis system ~•ras developed on a CYSER 172 <br />oomauter to analyze vegetation data collected during this study. Data <br />~ were input via keypunched cards that had been double punched and verified <br />for accuracy. Raw data print-outs were formatted like the original field <br />data sheets to facilitate additional data verification. <br />The procedures and formulae used to analyze vegetation production, Dover, <br />frequency, shrub height and density and basal area data are summarized <br />in S•?yoming DEQ Guideline #2, 1979 edition. Data analysis results are <br />presented by species and life form for each sampling point (e.g., Doves <br />quadrat) or transect and summarized for all sample points or transects <br />within a particular vegetation type. Statistical methods used in the <br />analysis such as calculation of means and standard deviations and <br />application of linear regression techniques to size/age data for aspen <br />and selected shrubs are standard, well~locumented techniques (Snedecor <br />and Cochran, 1967). Analysis results are formatted in tabular form to <br />C• facilitate access and interpretation. <br />Tree densities were calculated from transect point-tree distances using <br />the rethxl outlined by Smith (1979) <br />1. All point-tree distances in the sarple were summed and divided by <br />the total number of distances to obtain a mean distance of point <br />to tree: <br />Mean distance = fetal distance <br />number of distances <br />2. The Crean distance was squared to obtain the mean area covered on <br />the ground per tree. <br />3. The total number of trees per acre eras then determined by dividing <br />43,560 ft2 (number of ft2 in an acre) by the Wean area per tree. <br />Application of this technique to transect point-tree distances to <br />~• determine tree densities is illustrated by the following examq~le: <br />-15- <br />