C150240 Vegitation Montioring Analysis

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The key index that has decreased in value from baseline conditions is hydrogeomorphology condition, which accounts for 25% of the total weighted value. Section 1.1 of the GMM describes the criteria for rating hydrologic disturbances. The reservoir has already caused altered hydrology from the natural hydrologic regime, and an expansion magnifies the alteration into the newly inundated zone in which the GMM was assessing. Essentially by increasing the surface level of the reservoir the following hydrologic components have been altered in the newly inundated zone, although not necessarily in a negative way. ' • Hydrological source of the wetland • Wetland surface area • Condition of wetland habitat • Soil condition The other index that has decreased in value is wildlife habitat. This index contributes 5% of the ' total weighted value. Habitat value decreased for predators, birds, and reptiles with increased water elevation and fluctuations. Remaining indices have been relatively constant in scoring values from baseline conditions. ' The slight decrease of functional value in the hydrogeomorphology index has been compensated for with an increase in wetland surface area. Overall, the total wetland value for wetlands and fen ' within the newly inundated zone has increased from baseline conditions. CONCLUSION ' There was no significant change detected between the percent cover, species richness and species diversity within the various elevations (zones) or sites during the monitoring period (P-value > ' 0.05). There was no statistical change detected in total vegetation cover within the newly inundated zone (P = 0.49). There was no change discovered within the newly inundated zone in percent cover for the vegetation group carex (P = 0.31), graminoid (P = 0.94), and forb (P = 0.29) in either the carex-dominated emergent wetland or the willow-dominated shrub wetland. Change in willow ' cover and herbaceous understory cover in the willow-dominated shrub wetland was not statistically different over the monitoring period within the newly inundated zone (P = 0.53; P = 0.45). Although there was no statistically significant change (P-value < 0.05) detected, one potential trend may be present. Species richness may have decreased over the monitoring period (R2 = ' 0.70, P = 0.16). This trend has a weak linear relationship (R2 > 0.6, P-value < 0.25) and could be explained by a number of reasons. Natural variation, varying quadrat placements, human error, fluctuating growing season dates, timing of drawdown of water levels, differing precipitation, and ' grazing presence explain species with a relatively small percentage of cover possibly not being detected from year to year. ' Wetland has increased in size within the inundated zone from 3.38 acres to 6.49 acres. Function has increased, propelled by the increase in wetland acres. Total wetland (functional) value has increased 67% from a value of 2.91 in 2010 to a value of 4.45 in 2014. WestWater Engineering Page 10 of 14 February 2015