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the late 19`'' and early 201h century was, in this view, an artifact of human deforestation, not <br />natural processes. The debate has important implications for envisioning river restoration <br />targets, but definitive conclusions have been impossible to draw because the debate has not been <br />about whether there were trees or not-all have ageed there were at least some-but about the <br />extent and patterning of the riparian woodlands. The explorer-settler observations available in <br />the record are simply not sufficiently quantitative to settle the argument. <br />Characteristics and Value of Ecosystem Services <br />Rivers in open flat country typically support more complex ecological communities than <br />smaller woodland streams. More sunlight, more algae and zooplankton provide a broader base <br />for the food chain. In addition, rivers with small gradients meander, demonstrating a dynamic <br />equilibrium between erosion and deposition of sediment. Faster moving water scours out earth <br />from the outside curves of channels and deposits this load when the velocity slows at inside <br />curves. Stretches of maximum velacity and the deepest part of a channel lie close to the outer <br />side of each bend and then cross over near the inflection between the banks, resulting in zones of <br />erosion and deposition (Outwater 1996, p. 57-8). River backwaters, oxbows and chutes in a <br />meandering pattern were important to breeding, feeding and resting habitat for resident and <br />migrating waterfowl such as sandhill and whooping cranes, ducks, geese, and a variety of shore <br />birds including the least tern and piping plover. :Flood pulses re-worked stream channels by <br />clearing out woody vegetation and flushing out silt. <br />Most aquatic productivity has occurred in floodplains rather than in the main channel <br />(Outwater 1996) The transitional zone between river channel and prairie grasslands acted as a <br />buffer from the extremes of flowing water and arid uplands. Successive plant/animal <br />communities occupied meander loops as they were slowly transformed from aquatic channels to <br />isolated oxbows and finally to wet flood plain depressions. As long as the river system kept <br />creating new loops and cutoffs a succession of habitats suited to each type of ecological <br />community was maintained-i.e. the larger river.and floodplain sustained all stages of the process <br />and did therefore support a rich diversity of life. <br />Habitat Change <br />The Platte river basin has been impacted lby 15 major dams and reservoirs that are <br />supplemented by many smaller water diversion and storage projects. There are 106 storage <br />facilities on the South Platte alone holding an avurage of 2.8 million acre-feet of water (Eisel and <br />Aiken 1997). Upstream from Lake McConaughy on the North Platte River, there are 84 storage <br />works with a capacity of 4.3 million acre-feet. The total basin storage capacity is about 6 times <br />the average annual flow of the Platte at Grand Island. Dams and reservoirs in the Platte River <br />Basin provide a total storage capacity of over 7.1 million acre feet, with the Bureau of <br />Reclamation projects accounting for 2.8 million acre feet (Keyes 2002). Traditionally river <br />diversions were primarily for agricultural use, but higher value-added uses in the urban, <br />industrial, and post-industrial high technology aiid recreational sectors have pulled water out of <br />agriculture at a rapid rate.