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-12- Revised OCT 3 0 1961 <br />• DATA ANALYSIS <br />A data base management and analysis system was developed on a CYSER 730 <br />Cortq~uter to analyze vegetation data collected during this study. Data were <br />input via keypunched cards that had been double-punched and verified for <br />accuracy. Raw data print-outs were formatted like the original field data <br />sheets to facilitate additional data verification. <br />The procedures and formulae used to analyze vegetation production, cover, <br />frequency, shrub height and basal area data are suimiarized in Wyoming DE>1 <br />Guideline #2, 1979 edition. Data analysis results are presented by species <br />and life form for each s~npling point (e.g., Dover quadrat) or transect and <br />_ surtmarized for all sample points or transects within a particular vegetation <br />type. Statistical methods used in the analysis such as calculation of means <br />and standard deviations are standard, we11~1ocimiented techniques (Snedecor <br />and Cochran, 1967). Analysis results were formatted in tabular form to <br />facilitate access and interpretation. <br />The Shannon-Weiner species diversity index may be used to canpare ooimwiity <br />~rc{~osition data from a variety of sources. Differences in diversity may <br />be expected for communities at different stages of succession, in different <br />habitats, or at different times of the year. For example, diversity <br />indices calculated for vegetation data gathered at the beginning of or mid- <br />way through the growing season could likely be lower than those calculated <br />at the end of the growing season. These differences ~.ould result primarily <br />from the varying anthesis dates of vegetative species encountered in the grass- <br />forb stratum. A sample taken after the growing season Mould account for most <br />or all of the species that had bloar~l during that gracing <br />earlier samples cYould likely miss those species having late growing season <br />anthesis dates. Thus, the later in the season vegetative data supporting <br />diversity indices are gathered, the more accurate these indices will be in <br />reflecting the true vegetative species diversity. <br />4'he Shannon-Weiner index is used to armiunicate and oanpare species diver- <br />. sity for the grassland and upland sagebrush on affected and control areas <br />at Nucla Mine. This index is based on the Shannon-Weiner function from <br />the field of information theory (Margalef, 1967; MacArthur and MacArthur, <br />