Laserfiche WebLink
<br />CYCC proposes to increase the plant species diversity performance standard from <br />three species to four species, which are the dominant species on [he reclaimed <br />land and whose combined relative percent composition make up at least 64% of [he <br />community. No single species will contribute more than 40% of the relative <br />composition and at least one species will be a forb. <br />The procedure for calculating the diversity standard takes into consideration <br />the potential species diversity that might occur on mined land as imposed by <br />environmental factors which are reflected in the natural premine plant com- <br />munities. Since these factors are radically altered by mining, with the ex- <br />ception of the macro-climate, and the plant community structure (over the ten <br />year liability peroid) on reclaimed land has been, for the most part, pre- <br />determined by the imposition of woody plant density standards, available seed <br />and seed mixtures, planting methods, and cultural practices, a seemingly logical <br />procedure for determining a standard for species importance and richness based <br />on premine data is to evaluate all natural communities in a general and generic <br />manner. Presently, it is not possible tc predict with confidence what the <br />postmine seral and climax community may resemble or how it may be similar to the <br />premine communities in terms of structure, composition, or diversity. <br />The first step in preparing the diversity standard is to determine the relative <br />percent composition by species for each natural plant community. Each community <br />is individually ranked with the species in decending order. Then, all of the <br />values for the highest ranked species are added together and an arithmatic <br />average value is calculated which represents species number one on the species <br />curve. Each of the subsequent species are added together in the same manner and <br />an average composition curve is graphed as shown in Figure 1 and Figure la <br />attached. Notice that in Figure la and 2a that all of the curves are similar in <br />shape. The data presented in Table lb, Weighted Average Composition, was based <br />on the relative acres of disturbance given in Table 2, Relative Disturbance of <br />Natural Communities and Table 1, Average Composition (June 24 submission). <br />The second step is to prepare a curve representing the second derivaty of the <br />average composition curve. This curve represents the difference in the rate of <br />change between species. An example is given in Table la and the curve for the <br />1 <br />