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If the percentage change -is from mesic to xeric, then the duration of time the bootomalnd <br /> is inundated is effectively zero. The duration metric used herein change in percentage of <br /> bottomland in the xeric community. <br /> Intensity is defined in terms of total change in percentage of bottomland in community type <br /> mesic. <br /> 1) Negligible intensity - is herein defined as a net change in the total bottomland populated <br /> with mesic community by ± 10 percent. <br /> 2) Minor intensity is herein defined as a net change in the total bottomland populated with <br /> mesic community in the range ± 10 to 25 percent. <br /> 3) Moderate intensity is herein defined as a net change in the total bottomland populated <br /> with mesic community in the range in the range ± 25 to 40 percent. <br /> 4) Major intensity is herein defined as a net change a net change in the total bottomland <br /> populated with mesic community by ± 40 percent or greater. <br /> Table 3. <br /> Percentage Preimpound- No- Action Alternative A Alternative B Alternative C Alternative D <br /> vegetation as ment <br /> community <br /> type <br /> Xeric 3 9 6 6 4 6 <br /> Percent 0 -200 33 33 55 33 <br /> change to <br /> xeric <br /> community <br /> Mesic 69 57 60 61 67 61 <br /> Percent 0 -21 5 7 18 7 <br /> change from <br /> mesic to <br /> xeric <br /> community <br /> 1 Change in No- Action relative to the preimpoundment condition <br /> 2 Change in an action - alternative relative to the No- Action <br /> CONTEXT: Operations governed by the No- Action truncates the peak flows thereby <br /> effectively desiccating the topographic higher surfaces of the bottomland. Close to 21 <br /> percent of the mesic community is lost. The context of the impact is local- scale. Each of <br /> the action - alternatives A through D improves on the context in that the bottomland is more <br /> regularly watered and mesic communities would return. The gains are modest and each <br /> action - alternative is effective in a local context. <br /> DURATION: Operations governed by the No- Action result is a large increase in the <br /> percentage of bottomland in xeric condition therein implying a large decrease in higher peak <br /> flows necessary to water the bottomland. Key flows in maintenance of ecological <br /> communities are the 6,000 cfs duration flows. The increase in mesic community as a result <br />