Laserfiche WebLink
<br />floods and cold winters, such as the White River, the scouring action of <br />floods scrubs the substrate removing the periphyton. Also, the high <br />turbidity reduces photosynthic possibilities. Therefore, recovery of <br />the periphyton is delayed until late summer when increases in <br />populations usually occur (Hynes, 1970). <br />The five most common genera of periphyton-phytoplankton found in our <br />study (Table II .G-6) are the same as those found by Gulf and Standard <br />(1977) in the White River several miles above our study area. Gulf and <br />Standard's (1977) values for periphyton chlorophyll a content were <br />somewhat higher than xe found, which may be attributable to clearer <br />flows in the more upstream portion of the White River. <br />U <br />The very low populations of macrophytes is also typical of a swift, <br />scouring river. The presence of the plants in September follows the <br />pattern set by the plankton-periphyton--growth occurs only after the <br />high-water period hsa ended. <br />In summary, the White River in the vicinity of the proposed coal mine <br />has a fish fauna dominated by native species, the flannelmouth sucker <br />and speckled dace. F.Yotic species are present, but constitute a <br />relatively small percentage of the fish fauna. The endangered Colorado <br />squewfiah moves through the area, but does not appear to use the area <br />for more than very small portions of time. The benthic invertebrates, <br />plankton-periphyton and macrophyte communities also appear normal for <br />• <br />II.G-29 <br />