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In the next section, the species of plants found and then the characteristics of the <br />wetlands are discussed. Those sections will not only discuss the wetland enclosures but all <br />other wetlands found within the 6 mile long study area. <br />Species Present in the Wetlands <br />A complete floristic survey was not done on the study area, but the primary species and <br />their abundance were surveyed. Wetlands often exhibit similar floristic characteristics to other <br />well developed vegetation units. There are usually a very few species that are especially <br />abundant and widely distributed throughout the vegetation. Next are species that have lower <br />abundance but are also widely distributed. And last are a large number of species that are not <br />often found and tend to occur in isolated stands. This pattern reflects the tolerance curves of <br />each species. Abundant and widely distributed species often have broad tolerance curves that <br />allow them to live in a wide variety of habitats within the vegetation unit. Less abundant and <br />widely distributed species may have broad tolerance curves or may be somewhat more <br />selective or may be new invaders that will join the abundant and widely distributed species in <br />the future but have just not quite achieved that point yet. The uncommon and rare species <br />which often include the highest number of species usually exhibit rather specialized <br />requirements and can only live where the habitat characteristics match their "picky" tastes. In <br />this study only the first two categories were examined, although quite a number of species <br />were seen that would fit in the last category. Those are not listed because they do not <br />constitute a significant part of the vegetation assemblage. <br />Table l lists the 24 species that were found in the wetlands along the stream. This <br />table also lists the qualitative abundance of each species in both natural wetlands and <br />recovered wetlands. Recovered wetlands included the wetlands established in the mitigation <br />enclosures. Some of these species can also be found in adjacent "upland" vegetation that joins <br />the clearly defined wetlands. Also, on occasion, upland species were found that would creep <br />into the edges of the wetlands. But in both cases, the abundance of wetland species in uplands <br />and upland species in wetlands was very low. Ecologically though, such blending, where it <br />occurs, indicates a condition where the boundary between wetland and upland is a broad <br />transitional zone rather than an abrupt boundary. The more gradual the slopes between the <br />two units the broader this transitional zone is. Where the slope is steep the transitional zone <br />may be only a few inches wide and therefore forms a well defined boundary. But transitional <br />zones were also found within the stream channel itself and between different forms of wetland <br />vegetation. These transitional in-channel zones though tend to be very broad and sometimes it <br />is difficult to define where one unit ends and another begins. In particular these transitions <br />relate to the depth of sand accumulation and there seems to be a nearly 1:1 relationship <br />between sand accumulation and the type and extent of wetland development. However, with <br />Coal Creek Wetlands and Wetland Mitigation DA Permit 198811488 August 2003 Page 12 of 23 <br />