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This intensity of sampling is 1.56 times Trapper Mines's 1980 sampling <br />requirements. In fact, this is an optimistic estimate, since two pits at Trap- <br />per Mine include both cropland and rangeland, which would further increase tot- <br />al sampling requirements. <br /> Species diversity is another parameter for evaluating revegeta[ion success <br /> which needs reconsideration. Species diversity is considered by most plant <br /> ecologists [o be [he number of plant species in a particular area and [he <br />• manner in which the individuals are distributed. Unfortunately, precise <br /> definitions of these concepts and how they should be measured and evaluated are <br /> not well agreed on. Species diversity has, in fact, been the subject of <br /> intense debate amongst plant ecologists for many years and there is currently <br /> no concensus on exactly what it is. Many different concepts of the components <br /> of diversity and. how [hey should be considered have been discussed in the <br /> literature (Whittaker, 1960; Pielou, 196.G; McIntosh, 1967; Whittaker, 1970; <br /> Aill, 1973; Bonham, 1974; Pee[, 1974; Whittaker', 1975). <br />• <br /> The Shannon-Weiner (sometimes called Shannon-Weaver) index, as discussed <br /> by Larson (1980) for the Office of Surface Mining, was addressed by Peet (1974) <br /> who stated [ha[ the index is believed to hold some bias. In fact, all <br /> diversity indices are designed to bias or weigh[ the measured values to reflect <br /> various theories of the components of diversity and their significances. The <br /> danger in [he use of any such theoretical index is the way the weighting is <br /> done and its technical validity for [he applied situation. Each researcher who <br />' advances a new diversity index- professes [o have developed the best and most <br />i ecologically sound index. What must be remembered is that all such indices are <br /> as yet theoretical, unproven, and no[ we 11 accepted by ecologists. This point <br /> is made by Hi11 (1973) who stated: "Unfortunately, when we look for a suitable <br /> numerical definition, we find [hat no particular formula has a pre-eminent <br /> advantage, and that different authors have plausibly proposed different <br />~ indicies." It is therefore inappropriate [o apply a diversity index by <br />~ regulation. Controversial scientific issues cannot be resolved by regulation. <br /> <br />I Further, the dimensionless number calculated by a diversity index has little <br />-8- <br />..rP `~ ~9UC. <br />.~ <br />~~ <br />~~^~T!..-~-rw~°^Ti^.~-~rn--~..T-~ ~.r'T^~.1T~1.~9?.Rm~~l. i~"6.Tr^>T. '... _____l.. <br />