Walia Special Edition on the Bale Mountains (2011) - Zoologische ...

S. Rocky H. citrispinum/Artemisia/Kniphofia grassland
Rocky shrublands with tall, diverse vegetation. The dominant shrub species is variously A.
haumannii, K. foliosa, H. citrispinum, A. afra and H. splendidum. The ground cover is largely
grasses, with little bare soil.
T. Rocky Helichrysum grassland
Distributed at similar altitudes to T, this class differs in having more bare soil and grass, and a higher
frequency of Helichrysum species in the shrub layer. It is the dominant vegetation in the plain to the
east of Morebawa hill, including Kerenza valley.
u. Alchemilla abyssinica pasture
Alchemilla abyssinica is present throughout the Bale Mountains alpine zone, but is most prevalent
in class U. The low density of grasses and additional presence of A. pedata mean that Alchemilla
dominates the ground layer. Associated species are Carduus camaecephalus, Salvia merjame and
Trifolium sp. This class has a low proportion of rocks, and occasional K. foliosa and Helichrysum
bushes.
V. Grass pasture
Representing the grass-dominated pastures found on low-lying flat ground, gentle slopes and mesa
tops, this class is characteristic of the Web Valley. It has the highest occurrence of Salvia merjame
and, like the Alchemilla pasture, is highly seasonal, desiccating through the dry season and exhibiting
a flush of green growth as the rains begin.
W. Alchemilla pedata drainage lines and swamp edges
Class W has the highest proportion of open water, and the highest cover of three taxa which prefer
waterlogged soils: A. pedata, H. rueppelli and Ranunculus sp. The prevalence of Urtica simense
may be associated with high grazing levels in these seasonally productive pastures.
Table 4. Comparing plant species composition of clusters at each node. See Figure 2 for nodes and
Table 3 for species abbreviations. Species in bold are significantly more abundant, species in italics
are significantly less abundant than expected, i.e. standardised residuals (SR) >2 or