2012-04-02_REPORT - C1994082 (7)

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Woody Plant Density In the 2007 reclamation area, the 2009 - observed woody plant density level of 1420.5 stems per acre increased to 3812.2 stems per acre in 2011, which is very encouraging for such young revegetation. Comprising this total are big sagebrush, Saskatoon serviceberry, snowberry, and aspen. Species Diversity and Composition When the 2007 reclamation was only two years old in 2009, there was approximately two times as much relative cover by annuals and biennials (ESCO 2010) compared to the four year old data collected in 2011. The distribution of species density by lifeform (Figure 4) shows that the 2007 Reclaimed Areas are more similar to the reference areas than would appear to be the case from the lifeform distribution of relative cover (Figure 5). This shows that the basic components of the original ecosystem have indeed been returned and that it is a matter of relative proportions of species (and age or community successional status) that separates the reclaimed from the native vegetation. Perhaps the largest difference with regard to species density is in the native perennial forbs category, where native areas (at least the most extensive native types of Mountain Brush and Sagebrush) tend to have half again to twice as many species of native perennial forbs per 100 sq.m than the four year old 2007 reclaimed areas. Data for total native species density in the 2007 reclamation areas was 24.7 species per 100 sq.m. in 2011, nearly the same as the 24.9 species per 100 sq.m. observed in 2009. Average total species density per 100 sq.m. in the 2007 reclaimed areas did not exceed any of the reference areas (Figure 4). However, in the 1500 sq.m. sampled in 2011, a total of 42 native species were encountered. This well exceeds the average number of native species per 100 sq.m. in the various reference areas which ranges from 22 to 38 species per 100 sq.m. (see Table B -2). Within the first five random samples in the reclaimed area (i.e. with a random 500 sq.m.), 30 native species were encountered. Assuming that the development of species richness / diversity is a progressive matter, the existence of approximately equal level of richness that exists in 100 sq.m. of most of the reference sites, shows very favorable progress. Sample Adequacy A summary of sample adequacy calculations for the parameters of cover, herbaceous production, and woody plant density is presented in Table C -4. As can be seen in this table, the data sets for cover for the 2007 reclaimed and mountain brush reference areas did not achieve sample adequacy. The data sets for production collected in the reclaimed and the reference areas did not achieve sample adequacy as well. Note that no formal testing for Phase III bond release 12