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• of variation from that of the closest fit curve for all reclamation azeas and total herbaceous <br />production (R2= 0.7396, Figure 4). Figure 14 depicts the best-fit curves for the 1985, <br />1986, and 1987 reclamation azeas data individually. Individual correlation For the 1985, <br />1986, and 1987 areas is perfect, with each showing a correlation coefficient of one. The <br />form of the best-fit curves and the correlation coefficients reveal that the curve <br />incorporating all cover data from the Januazy-July precipitation regime and the 1985, <br />1986, and 1987 production data (Figure 13) is a close approximation of the results of the <br />individual reclamation area plotting. Unlike the curves for total vegetation cover, the <br />sigmoid shape of the best-fit curves for herbaceous production reveals only one inflection <br />point within the data range at approximately five inches precipitation. This suggests that <br />at very low precipitation levels total herbaceous production would be higher than at <br />precipitation ranges between four and six inches. <br />Total vegetation cover and September-July precipitation for the 1985, 1986, and 1987 <br />reclamation areas is shown collectively and individually in Figures 15 and 16. The <br />collective plot reveals a third order polynomial as the best-fit curve with two inflection <br />points in the data range. A correlation coefficient of 0.9654 was obtained for this data set, <br />the same value as that for the collective production data and the January-July precipitation <br />data. Individual plotting of the 1985, 1986, and 1987 reclamation areas total herbaceous <br />production and September-July precipitation shows individual correlation coefficients <br />equal to one (perfect correlation). As noted with the January-July plots, these curves <br />reveal inflections that indicate minimum and maximum total cover values within the data <br />. set range that are not likely borne out in the natural world. <br />Collectively, separating the 1985, 1986, and 1987 reclamation azeas from the total data set <br />increased the amount of variation explained by the best-fit curves. Individual reclamation <br />azea curves for total vegetation cover, total herbaceous production, and September-July <br />precipitation yielded equal or higher correlation coefficients than those for January-July <br />precipitation plots. Combined data from the three reclamation area years for the <br />pazameters did not vary significantly between the two precipitation regimes. The form of <br />the best-fit curves, with the presence of inflection points within the observed data range <br />continued to present a difference between empirical observations and the theoretical <br />relationships. <br />3.4 1995,1997, and 1998 Reclamation Areas <br />Total Vegetation Cover <br />The results of curve fitting for the January-July and September-July precipitation regimes <br />and total vegetation cover values for the 1995, 1997, and 1998 reclamation areas aze <br />presented in Figures 17 through 20. <br />Figure 17 depicts the closest fit curve for the January-July precipitation and all vegetation <br />cover data from the 1995, 1997, and 1998 reclamation azeas for the period from 1998- <br />2001. The closest fit curve for this data set is a broad third order polynomial with <br />-9- <br />