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Note that this test addresses total species density, not just native species density (see D) below). <br />Noxious weeds are omitted. The point of addressing total species density, including <br />annual/biennial species and introduced species, is that the total species density is arguably a <br />strong indication of the existence of niche spaces that could eventually be occupied by the native <br />forb and woody plant species typical of the pre-mining plant communities. <br />The final step for this assessment will be comparison of the mean total species density of the <br />BRB to the reference area-derived standard number (above). If the reclaimed area mean <br />exceeds the standard, the Test B is passed. If the BRB mean is less than the standard, a <br />hypothesis test will be undertaken. This would be accomplished using the expression set forth <br />above for aone-sample t-test comparing the reclaimed area species density mean. <br />Alternative Test C): Assessment of the Distribution of Species Density Among Lifeforms <br />in Comparison to the Reference Areas <br />This test relates to the distribution of the presence of species among the various Lifeforms in <br />comparison to the reference areas. This standard will use the Motyka similarity index to assess <br />the resemblance of the distribution of species density by lifeform of the reclamation vegetation to <br />that of the reference areas. Because the average internal resemblance (i.e. between-sample <br />. similarity) of applicable reference areas for species density data is often in the range of 70%, the <br />proposed standard is 63% (0.9 x 70%). (For this calculation, data from the extended reference <br />areas (SagebrushlSnowberry, Mountain Brush, and Aspen) from the nearby Seneca II-W Mine <br />were examined. The Seneca II-W extended reference areas extend across sections of landscape <br />more comparable in dimension to the BRB areas than are the comparatively small Seneca II <br />reference areas. Thus, they are thought to be more indicative of pre-mining inter-stand <br />community diversity). <br />The Motyka similarity index will be used as follows: <br /> <br />Where <br />c = the smaller of the paired species density values (for each lifeform) of the reclaimed <br />and reference areas` <br />a =total of species density values for Lifeforms of the reclaimed areas <br />b =local of species density values for the Lifeforms of the reference area* <br />I ~ 10 <br />