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infrared photographs were used to determine the widest channel. The centerline was documented in a line theme called (baseline.shp). Anchor points were established every 400 meters along the centerline and documented in a point theme called (400m-pts.shp). This file was updated with the river miles (400ma_pts.shp) using the "River Miles for the Central Platte River" dataset published by the U.S. Bureau of Reclamation, Great Plains Region, Platte River EIS Office. For First Increment data to be most useful, monitoring activities will need to survey the exact same sites. For this reason, the centerline will not be changed if the river thalweg moves during the First Increment. For example, there will be geomorphic monitoring designed to evaluate cross sections of the river at an anchor point. The cross sections will be oriented perpendicular to flow and the endpoints will be marked oil the banks. Throughout the First Increment, the direction of flow of the river may shift at an anchor point, but for comparison purposes, the orientation of the cross section should not be shifted. Keeping the centerline and the sample activities in the same location will increase precision for trend detection. The monitoring design has intentionally avoided stratification in the membership design. Since attributes of long term monitoring locations evolve through time, a stratified design will tend to lose efficiency as monitoring data accumulate. For example, it is common far a sample unit that has been assigned to one stratum at the beginning of the study to be more similar to another stratum after a number of years (e.g., grassland in Year 1 has developed into a shrubland by Year 10). In this case the stratum of the sample unit at analysis time is unclear. The sample unit could be analyzed with the initial stratum (grassland) resulting in high within strata variance since the units attributes have changed. Alternatively, the sample unit could be moved to the ecologically appropriate stratum (shrubland) for the analysis, though the probability of inclusion of this sample unit in the new stratum is un-defined. A systematic placement of points throughout the study area will ensure coverage of each stratum in proportion to the relative abundance of the stratum each year. Monitoring data analysis - Analyses conducted with monitoring data will include the estimation of linear trend and status (mean levels). Trends can be estimated at one individual sample unit (gross trend) and across all sample units (net trend; Duncan and Kalton 1987). The average of gross trends across each sample unit will be used to estimate net trend (Urquhart et al. 1998). Ecologically structured variance components (identifiable by the revisit design) of net trend can be incorporated into a standard linear statistical model resulting in powerful estimates of the trend of interest (Urquhart et al. 1998). Statistical analysis methods such as post-stratification (Thompson 1992) will be used to estimate the status and trend of certain groups of inonitoring locations. Locations can be grouped into geomorphological or bridge segments for analyses that are consistent with historic analyses. Alternatively, locations can be grouped into areas with significant influence by human structures (bridges, diversions, etc.) and locations not directly influenced by human structures. Sampling units will be classified into strata before each analysis so that the within strata variance is minimized. September 1, 2006 Adaptive Management Plan 35