2007-12-21_REVISION - C1981013 - Laserfiche WebLink

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Woody plant density was not collected during the 2005 vegetation sampling effort.. 2006 Data In 2006 cover data was collected using the same methods as in 2005. Sample adequacy for vegetative cover was achieved in all four sampling units. Vegetative cover on the pastureland reclaimed area (20.9%) exceeded the cover on the pastureland reference area (19.5%). The reclaimed rangeland cover (14.5%) exceeded the cover on the rangeland reference area (12.8%). Vegetative cover in both reclaimed communities is successful. Production data was collected using thirty randomly located 0.25 m2 plots. Sample adequacy was not achieved using the standard formula for any of the four sampling units. As allowed by Rule 4.15.11 (2) (c) a reverse null approach was used. In both cases, the null hypothesis of equality was rejected; the alternative hypothesis (reference area mean less than reclaim area mean) was accepted. This was a statistical confirmation of what was intuitively obvious from the data. The t-tests demonstrated that the reclaim area means in both the pastureland and the rangelands exceed the respective reference area means at the 80% level of statistical confidence, pursuant to Rule 4.15.11(2)(c). The species diversity standard for the reclaimed rangeland was achieved in 2006 as documented in Table A-7. Contributing cool season grasses were smooth brome, western wheatgrass and slender wheatgrass. Warm season grasses were blue grama and little bluestem. The forb was alfalfa. Woody plant density was not collected during the 2006 vegetation sampling effort. Summary Revegetation success has been largely successful. There are a couple of details to address before the final findings can be prepared. 1. Please correct the conversions for the 2006 production data and revise the report as necessary (as discussed in comments and highlighted chart above). 2. The Division is requesting that two separate t-test demonstrations be presented for the 2005 rangeland production data and included in the final bond release report. The first test should be a two sample reverse null t-test, based on the sample size of 90 in the reclaimed area and reference area (each quadrat treated as an independent observation). The second test should be a two sample reverse null t-test, based on a sample size of 15 in the reclaimed area and reference area (each transect treated as an independent observation). Both tests should be based on "corrected" quadrat data (undesirable component removed from the data from each quadrat prior to calculation of sample statistics). If both tests conclude that reclaimed area