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January 26, 2024 <br />Don Peterson <br />Page 8 of 21 <br />Reference: Water Quality Assessment of Silver View Pond, Mounds View, MN <br />Table 5. Aquatic plant taxa and littoral frequency of occurrence in Silver View Pond. <br />NIPW <br />Early Late Season <br />Season <br />SUBMERSED TAXA <br />Nymphaea odorata <br />American white waterlily <br />49 <br />55 <br />Nuphar variegate <br />Bullhead pond -lily <br />1 <br />-- <br />Chara sp. <br />Stonewart <br />46 <br />38 <br />Elodea canadensis <br />Canadian waterweed <br />9 <br />12 <br />Ceratophyllum demersum <br />Coontail <br />45 <br />44 <br />Potamogeton zosteriformis <br />Eel -grass pondweed <br />6 <br />3 <br />Potamogeton foliosis <br />Leafy pondweed <br />-- <br />2 <br />Potamogeton pusillus <br />Small pondweed <br />37 <br />3 <br />Stuckenia pectinata <br />Sago pondweed <br />3 <br />3 <br />FLOATING TAXA <br />Lemna trisulca <br />Ivy -leaved duckweed <br />13 <br />23 <br />Lemna minor <br />Small duckweed <br />96 <br />58 <br />Wolffia sp. <br />Watermeal <br />81 <br />58 <br />Spirodela polyrhiza <br />Large duckweed <br />97 <br />59 <br />Utricularia vulgaris <br />Common bladderwort <br />1 <br />6 <br />EMERGENT TAXA <br />Typha sp. <br />Cattail <br />-- <br />-- <br />Sagittaria sp. <br />Arrowhead <br />-- <br />-- <br />Schoenoplectus acutus <br />Hardstem bulrush <br />-- <br />-- <br />Note that at some points in the late season survey, watermeal was at 100% coverage on the surface of the <br />water. However, watermeal. coverage on the rake tow was lower at these points, so the rake tow values <br />were incorporated into the statistical analyses per the protocol. <br />Sediment Phosphorus Chemistry <br />Phosphorus release rates under oxic and anoxic conditions are shown in Figure 3. Rates over 2 mg/m2-d <br />are considered high and may indicate the need to implement actions to reduce release of phosphorus from <br />pond sediments. Anoxic release rates were higher than oxic release rates in Silver View Pond, which is <br />typical. Anoxia -driven phosphorus release is due to reduction of iron that is bound to phosphorus, which <br />causes the bonds to break and allows dissolved phosphorus to diffuse from the sediments. Oxic release is <br />typically driven by aerobic decomposition of organic matter where dissolved phosphorus is released in the <br />process. Station 3 had nearly equal rates of anoxic and oxic release which is a function of the high <br />Design with community in mind <br />