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An example of possible changes follows. The proposed change would include four sequential <br />study reaches: 1) upstream control reach where no action is taken, <br />2) woody vegetation clearing reach, <br />3) vegetation clearing and channel widening and leveling reach, and <br />4) downstream deposition reach. <br />The changed proposal covers two management actions, 1) the removal of woody vegetation from <br />50 acres along one half mile of the banks of the main channel of the Platte River, and 2) the <br />removal of all vegetation from 50 acres along one half mile of the downstream banks of the main <br />channel of the Platte River and the widening and leveling of that channel reach, by cut and fill of <br />the cleared land and the main channel, to provide a shallow main channel with a width of 1150 <br />feet. A control section of the main channel upstream of the action sites would not have any <br />actions applied. The hypotheses "that little or no bank or over-bank erosion would occur at the <br />control and clearing only sites, that the clearing only site would grow back, and that the cleared <br />and leveled site would be maintained clear of vegetation by annual pulse flows" would be tested. <br />The changed monitoring and research proposal includes the following tasks: <br />a) topographic surveys of 8 complete cross sections (6 downstream), once per year, <br />b) sediment sampling of 8 complete cross sections (6 downstream), once per year, <br />c) ground photography of 8 complete cross sections (6 downstream), once per year, <br />d) installation of one continuous gage for measuring water levels, <br />e) cross sectional measurements of flow rate at the gage site, 12 times per year, <br />f) topographic surveys of 50 single channel cross sections, once per year, <br />g) sediment sampling of 25 single channel cross sections, once per year, <br />h) ground photography of 50 single channel cross sections, once per year ? <br />i) analysis of the data using computer models of the river hydraulics and sediment transport to ? <br />assess the impacts of clearing the woody vegetation on channel geometry and species habitat, <br />and <br />j) preparation and publication of two data reports and an interpretive report, the latter published <br />in the peer-reviewed literature.