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<br /> <br />A comparison between the species cover of the affected area of the <br />Dry Meadow community and the affected area of the Wet Mixed Shrub community <br />resulted in a similarity of 2% (Table 9). Combining the species into growth- <br />forms and then making the cover comparison resulted in similarity value of <br />27% (Table 10). It is clear that comparing visually distinct areas results in <br />low similarity indices, regardless of the degree of clustering employed. <br />Comparison of the Motyka Index and the Shannon-Wiener Index of Diversity for <br />Evaluating Reclamation Success <br />The Shannon-Wiener index of diversity proposed by Pielou (1975) and <br />supported by the OSM Region V Technical Analysis and Research Staff can be <br />used to assess vegetation diversity in areas to be affected by mining. The <br />Shannon-Wiener index involves logarithmic transformations of the data after <br />they have been proportionalized. The transformed values are summed, thereby <br />creating a diversity index (H'). The formula used is: <br />H' _ - pilogpi <br />where: pi = Ni/N <br />Ni = quantitative value for individual component <br />N =sum of quantitative values for all components <br />The major drawback of the Shannon-Wiener index is that while it may be <br />a good indicator of community diversity, communities that have similar indices <br />of diversity may have few, if any, species or growth-forms in common. A degree <br />of commonality of species or growth-forms between reclaimed and reference areas <br />is often considered to be important in assessing reclamation success. For <br />example, a reclaimed area may support a significant weed population, adding to <br />its apparent diversity. The weeds do not help meet the proposed post-mining <br />land use as it is represented by the reference area. However, individual <br />