2014-10-15_PERMIT FILE - C1982056A (7)

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Species Diversity Evaluation - Species diversity for the reclaimed communities will be evaluated using the following four (4) tests. Success would be demonstrated by passing the first test (A) and at least two of the • remaining three tests (B, C, and D). Mandatory Test A: No Overwhelming Dominant - No single plant species may exceed 60 percent relative cover. Alternative Test B: Total Species Density Test - It is proposed that this overall reclamation diversity standard be judged based on the species density values observed, along with cover sampling in 100 square meter sample plots (refer to previous discussion of species density sampling). It is further proposed that the species density numbers be subjected to sample adequacy assessment in the usual manner. For purpose of establishing the range of species density within the reference areas, the 75 percent range of variation would be established as: (z) * (s) Where: z = the number of standard deviations (both ways from the mean) encompassing 75 percent of the normal distribution (= 1.15; see Rohlf and Sokal 1969, Table P) s = standard deviation (n -1) * means multiply The standard would be the point at which the central 75 percent of the distribution of overall species density in the reference areas begins, or in other words, the selected standard is the midpoint (in terms of probability distribution) of the lower half of the range of variation of the reference areas. Mathematically this would be: • Mean reference area species density (no. of species per 100 square m) - 1.15 s Note that this test addresses total species density, not just native species density (however, also see Alternative Test C below). Noxious weeds are omitted. The point of addressing total species density, including annual/biennial species and introduced species, is that the total species density is arguably a strong indication of the existence of niche spaces that could eventually be occupied by the native forb and woody plant species typical of the pre - mining plant communities. The final step for this assessment will be a comparison of the mean total species density for the reclaimed area, to the reference areas - derived standard number. If the reclaimed area mean exceeds the standard, the Test B is passed. If the reclaimed area mean is less than the standard, a hypothesis test will be undertaken. This would be accomplished using the method described in the Hypothesis Testing discussion for a one - sample t -test comparing the reclaimed area species density mean. Alternative Test C: Assessment of the Distribution of Species Density among Life forms in Comparison to the Reference Areas - This test relates to the distribution of the presence of species among the various life -forms in comparison to the reference areas. This standard will use the Motyka similarity index to assess the resemblance of the distribution of species density by life -form of the reclamation vegetation to that of the reference areas. Because the average internal resemblance (i.e. between - sample similarity) of applicable reference areas for species density data is often in the range of 70 percent, the proposed standard is 63 percent (0.9 x 70 percent). The Motyka similarity index will be used as follows: • ISno = 2c / (a + b) RN08 -05 2.05 -117.1 03/12/10