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Species Diversity and Composition <br />When the 2006 reclamation was only two years old in 2008, there was over five times as much <br />relative cover by annuals and biennials (ESCO 2009) compared to the seven - year -old data <br />collected in 2013. <br />The distribution of species density by lifeform (Figure B -4) shows that the 2006 Reclaimed Areas <br />are more similar to the reference areas than would appear to be the case from the lifeform <br />distribution of relative cover (Figure B -5). This shows that the basic components of the original <br />ecosystem have indeed been returned and that it is a matter of relative proportions of species <br />(and age or community successional status) that separates the reclaimed from the native <br />vegetation. Perhaps the largest difference with regard to species density is in the native <br />perennial forbs category, where native areas tend to have half again to twice as many species of <br />native perennial fortis per 100 sq.m than the seven - year -old 2006 reclaimed areas. Average total <br />species density per 100 sq.m. in the 2006 reclaimed areas was nearly equal to two of the three <br />reference areas (Figure B -4). In the 1800 sq.m. sampled in 2013, a total of 61 native species <br />were encountered. This well exceeds the average number of native species per 100 sq.m. in the <br />various reference areas which ranges from 24.6 to 28.9 species per 100 sq.m. (see Table B -2). <br />Within the first two random samples in the reclaimed area (i.e. with a random 200 sq.m.), 27 <br />native species were encountered. Assuming that the development of species richness / diversity <br />is a progressive matter, the existence of approximately equal level of richness that exists in 100 <br />sq.m. of most of the reference sites, shows very favorable progress. <br />Sample Adequacy <br />A summary of sample adequacy calculations for the parameters of cover, herbaceous production, <br />and woody plant density is presented in Table B -4. As can be seen in this table, the data sets for <br />cover for the 2006 reclaimed and all reference areas except Mountain Brush achieved sample <br />adequacy. The data sets for production collected in the reclaimed and the reference areas did <br />not achieve sample adequacy as well. Note that no formal testing for Phase III bond release <br />were undertaken this year, so achievement of adequacy was not at issue. As would be expected, <br />minimum sample sizes for background area woody plant density sampling far exceeded those <br />taken. <br />13 <br />