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

Figure 1. Map with the approximate locations of the glades in the three strata sampled in the study.
The outline of Bale Mountains National Park is shown, as are the main rivers and roads.
In each glade except for one, the vegetation was sampled. In Harrawa, part way through the
field work, the site became inaccessible, due to rising river levels therefore only soil was sampled
there.
Historical land uses were investigated through interviews with one key informant from Rira
and information provided was crosschecked through casual interviews with local inhabitants and
validated through field observations.
Soil profile description, sampling and analyses
In each glade, three soil pits were dug at a random location inside the glade at a distance >15 m
from the edge of the glade and the profile of one described according to Fitzpatrick (1977). Samples
were taken from each pit at the depth intervals of 0cm-20 cm and 30 m - 50 cm for a total of three
replicates for each depth interval at each site. The same procedure was applied to each forest site.
Soil samples were air dried for at least one week under a shelter then sieved using a 2 mm soil sieve
before being stored in sample bags and hence transported to the laboratory in Addis Ababa.
Soil samples were analysed for pH, texture, organic carbon, total nitrogen, total exchangeable
bases (sum of Na, K, Ca and Mg), base saturation, cation exchange capacity and electric conductivity;
in all cases, standard methods were used (Black et al. 1965).
Vegetation data
On each glade aboveground biomass was clipped in five randomly located 50 cm x 50 cm plots. Plants
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