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area of 0.82 square feet. Transects were established across the area to be examined and samples were taken every <br />10 feet. Each transect included 100 samples Therefore, the transects were 1000 feet long. Each transect included a <br />total of 81.85 square feet sampled. <br />The cover was estimated based on the percent of the quadrat occupied by living plant materials. Of course, <br />in some cases, duff contained within the living plant material was also counted, but duff between living materials <br />was not counted in the cover value. For revegetation land, the same standard was used. Weeds were not counted in <br />the cover value in natural or reclaimed areas. Therefore, the cover values include only the desirable vegetation and <br />not the ephemeral weeds. This provides a better estimate of cover for judging long term survival potential. <br />Data Analysis: Because the composition of the natural vegetation differs from the composition of the <br />reclaimed vegetation, a species by species comparison is not feasible. Furthermore, as noted above, because the <br />standard relates to cover rather than composition, cover values for each sampling transect can be compazed <br />directly. However, it cannot be expected that reclaimed vegetation will necessazily have the same cover value as the <br />natural vegetation because the growth form and species composition of the two vegetation units differ. Therefore, <br />the comparison has to be statistical in nature. <br />Although average cover on each of the reclaimed vegetation transects can be compared directly to the <br />average cover of the natural vegetation, that is not very meaningful when comparing vegetation units of such <br />drastically different ages and extent of development. Therefore, to be meaningful, the cover values are compared <br />through the sample standazd deviation which is the square root of the sample vaziance. Standazd deviation is the <br />amount of deviation from the mean any one sample taken from a population might show. As a result, an average <br />cover value outside the range of deviations from the mean of the control (natural vegetation) can indicate whether <br />the cover value of the revegetation area is within a range that would probably represent a population that, with <br />respect to cover, is of the same population as the control. Put another way, if the average cover of a revegetation <br />azea is within the statistically defined maximum to minimum cover value range of the natural vegetation then the <br />revegetation can be considered to have a cover that is, statistically, the same as the natural vegetation. [f this is true <br />then the cover standard for revegetation adequacy is assumed to have been met. The maximum to minimum range <br />of the natural vegetation is determined by adding the standard deviation to the mean cover value for the maximum <br />and subtracting the standard deviation from the mean cover value for the minimum. <br />One additional subject that needs attention in sampling is knowing whether enough samples have been <br />taken to represent the unit being sampled. This is not always an easy chazacteristic to determine before doing the <br />sampling. Without knowledge of the variations within the unit being studied one can't know how many samples aze <br />enough samples. That isn't known until the sampling is done. <br />Two approaches can be used to determine when enough samples have been taken. First is to sample more <br />than will likely be needed; this, again, is still not easy to determine. Second, is to monitor the running averages <br />while the sampling is being done. With modem handheld computers this is fairly simple to do. <br />In this study, rather than monitoring the running average, 100 samples were taken along each transect. <br />Experience has shown that only in highly vaziable vegetation are 100 samples not enough and in grassland the <br />vegetation is more often than not reasonably uniform. After the sampling was done, the data were analyzed to <br />Reclamation Status -Coal Creek Resources M-1988-044 August 2002 Page 2 of 10 <br />