1990-10-03_REPORT - C1980005 - Laserfiche WebLink

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Species Density and Species Composition Tables 1 through 10 show species density data from each cover sample; these data are summarized in Table 30 and are graphically depicted in Figure 4. Species composition, as reflected in cover data, is present in Tables 1 through 10. Table 31 summarizes the relative cover data from these tables by lifeform and provenance. Figure 5 graphically depicts the same data. Species and lifeform density data reflect both total species/lifeform richness and equitability. The latter is incorporated by virtue of the fact that the occurrence of species is tallied within fixed unit areas (100 m2), and thus frequency is addressed simultaneously with species richness. The highest total species density of all areas was observed in the young reclaimed areas (Areas E, F, G, and H), where annual and biennial weedy plants are abundant ine early stages of secondary succession. Highest native species density was in Mountain Brush and Sagebrush References Areas (19.9 and 22.2 native species per 100 m2), but the 1985/1986 Wolf Creek and Wadge reclamation areas (Areas E and G) were fairly close behind at 17.3 and • 15.5 native species per 100 m2. The 1987 Wolf Creek and Wadge areas (Areas F and H) were also fairly high at 12.2 and 12.5 native species per 100 m2, respectively. The 1980/1982 Wadge and Wadge Pasture areas (Areas C and D) were moderate in native species density at 8.2 and 9.6 native species per 100 m2, respectively. Lowest native species density (and total species density) were the pre-law and 1977 Wadge areas (Areas A and B) with only 1.0 and 4.0 native species per 100 m2, respectively. Annual and biennial (orbs were, not unexpectedly, most diverse in the young reclamation area (Area E, F, G, and H); this was true for both introduced and native annuals and biennials. Introduced perennial forb species were rather uniformly present at about 1.5 to 3 species per 100 m2, except in the youngest (1987) Wadge area (Area H) and the reference areas where they were less than one species per 100 m2. Native perennial forbs are almost nil in the pre-law areas (Area A) and progressively more abundant in the 1977 Wadge and 1980/1982 Wadge areas (Areas B and C) at 1.3 and 2.4 species per 100 m2, respectively. Wadge Pasture was observed to have 3.7 native perennial forb species per 100 m2. A substantial increase in native perennial forb presence was seen in the younger reclamation where native perennial forb • species ranged from 6.1 species per 100 m2 (1987 Wolf Creek, Area F) to 8.6 species per 100 13