2007-12-31_REPORT - M1988044 - Laserfiche WebLink

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provides chazacterization of each species on each transect as well as over the entire exclosure and, finally, for all woody plants over the entire exclosure. This nested results helps provide a useful look at what contributes to the overall chazacter of the protected area. The second part of the table shows a comparison of 2006 and 2007 results using the same nested pattern. For this, the 2006 data was examined again to produce values that are consistent with the 2007 analysis so they could be compared on a valid basis. Where the 2006 and 2007 sampling methods differed, the 2006 data was adjusted to simulate the 2007 sampling method. Although direct comparison of 2006 and 2007 results could be done, the results of a direct compazison are not actually valid where sampling techniques differed. That is, where alternating square meter quadrats were taken in 2006 and a continuous transect was used in 2007, the simple results from each are actually not comparable because of the great difference in the actual azea sampled. With statistical corrections though, comparison is valid if the corrected data from 2006 and the raw data from 2007 are examined using the same formulas. This year, cover values are based on that portion of each transect where woody vegetation is encountered. Density is stated for both the woody vegetation portion of the transect as well as the entire transect. This distinction is made this yeaz because in most of the exclosures, a significant part of the transects would not generally be considered woody plant habitat. This mainly includes the slopes that rise above the primary portions of the riparian comdor. As has been demonstrated many times before at this site and other sites, often a change in elevation of just a few inches in these riparian corridors can result in dramatic changes in the potential vegetation that can exist there at this point in time. That can change as conditions change, but at this point in time side banks that are included in the transects should not be considered in calculating cover or density as that is not actually habitat for the species of interest. Nevertheless, side slopes must still be included in the data analysis for two reasons. First, often the woody vegetation habitat starts at or very near the bottom of the side slope. And second, these slopes should be included to monitor any changes in the point where strictly bottomland species (woody or herbaceous) first occur. If this shifts in either direction then it could be indicative of a change in the groundwater hydrology that is supporting the riparian woody and herbaceous vegetation. Such changes, because of the high sensitivity of this vegetation to hydrologic conditions, aze important to note especially if there is a sudden and unexpected change in the desired vegetation. Suffice it to say, at this point, no changes have been noted in the boundary between the strictly riparian and the adjacent, more elevated riparian habitats. But these boundaries are noted with each sampling just in case there is a change. Although other patterns are evident in these data, most of them, at this point, are of only a general interest. One of these is the table row showing the "height SSD" which can be interesting and quite revealing. This value is the sample standard deviation from the mean for the plant heights. Where there is a wide range of heights as indicated in the table rows showing maximum and minimum heights, the sample standard deviation can be quite large. But that situation can also 2007 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 6