Walia Special Edition on the Bale Mountains (2011) - Zoologische ...
Walia Special Edition on the Bale Mountains (2011) - Zoologische ...
Walia Special Edition on the Bale Mountains (2011) - Zoologische ...
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Goba to Dello Mena road. The excepti<strong>on</strong>, hora Higan, is found within an area of <strong>the</strong> eastern forest<br />
widely used for coffee harvesting.<br />
Properties<br />
Measurements were taken at <strong>the</strong> end of <strong>the</strong> wet seas<strong>on</strong>, when <strong>the</strong> horas are c<strong>on</strong>taminated by<br />
freshwater. In order to be properly interpreted, <strong>the</strong> following values of pH and c<strong>on</strong>ductivity should<br />
be complemented by values obtained from sampling during <strong>the</strong> dry seas<strong>on</strong>, when c<strong>on</strong>taminati<strong>on</strong><br />
would be less.<br />
As expected, electrical c<strong>on</strong>ductivity (EC) emerged as a measure of <strong>the</strong> attractiveness of <strong>the</strong><br />
horas for livestock husbandry, with <strong>the</strong> most used horas being also <strong>the</strong> most saline. Hora Sankate<br />
and hora Chakota are excepti<strong>on</strong>s: <strong>the</strong> first is <strong>the</strong> most saline in this survey (3.2 mS), but its locati<strong>on</strong><br />
by <strong>the</strong> side of a river might limit its accessibility and usability; <strong>the</strong> sec<strong>on</strong>d is perceived to be infested<br />
by some kind of parasite, <strong>the</strong>refore it is little used despite its relatively high salinity (2.2 mS). All<br />
of <strong>the</strong> rarely used horas have diluted water with salinity levels below 1 mS. Am<strong>on</strong>g <strong>the</strong> most used<br />
horas, three have salinity between 1.5 mS and 2.0 mS (Abba Usman, Dofo and Waticha) and two<br />
have salinity between 2.0 mS and 2.5 mS (Higan and Dokke’). The salinity of hora Worg<strong>on</strong>a in<br />
<strong>the</strong> Sanetti plateau was also tested for comparis<strong>on</strong>, giving a reading of 6 mS. This c<strong>on</strong>firms <strong>the</strong><br />
excepti<strong>on</strong>al salinity of hora Worg<strong>on</strong>a and explains why it is c<strong>on</strong>sidered high quality by locals.<br />
The large majority (32) of <strong>the</strong> active horas have pH between 6 and 8; three horas have<br />
pH greater than 8 (Alachera), and three have pH lower than 4 (Bukure, Huluke and Ebicha). The<br />
pr<strong>on</strong>ounced variati<strong>on</strong> in pH, which identifies alkanine horas (pH > 8) and acidic horas (pH < 4),<br />
underlines heterogeneity of <strong>the</strong> hydrological system that should be investigated in detail. The horas<br />
in <strong>the</strong> forest could be used to study <strong>the</strong> properties of <strong>the</strong> different catchments, <strong>the</strong> relative water<br />
retenti<strong>on</strong> times and alterati<strong>on</strong> processes, as a functi<strong>on</strong> of variati<strong>on</strong> in geology, land-cover and landuse.<br />
The BMNP is situated within a formati<strong>on</strong> of alkaline basalts with granitic inclusi<strong>on</strong>s (GSE<br />
1972). Granitic rock outcrops were occasi<strong>on</strong>ally found in <strong>the</strong> BMNP during <strong>the</strong> survey which may<br />
be associated with <strong>the</strong> acidic springs and have implicati<strong>on</strong>s for <strong>the</strong> vegetati<strong>on</strong>.<br />
Use, property regime and access<br />
Horas are used as a source of mineral supplement for livestock (cattle, sheep and goats). Water from<br />
<strong>the</strong> horas is perceived to enhance fat, fertility and resistance to diseases. Particular types of clay,<br />
locally called “haya”, are also used as mineral supplements. Generally, horas are fenced to prevent<br />
<strong>the</strong> livestock c<strong>on</strong>taminating <strong>the</strong> source or falling into <strong>the</strong> well, at times several metres deep. On top<br />
of <strong>the</strong> circular st<strong>on</strong>e fence (gimba) a wooden fence is generally erected. The livestock attendant<br />
pours <strong>the</strong> water into an external wooden channel (bidiru’), where livestock are allowed to drink.<br />
C<strong>on</strong>structi<strong>on</strong> of <strong>the</strong> gimba may be limited by availability of st<strong>on</strong>es, as in hora Dokke’. There, cattle<br />
are kept away from <strong>the</strong> main source, at <strong>the</strong> center of <strong>the</strong> glade, by draining <strong>the</strong> water through a l<strong>on</strong>g<br />
drainage channel reaching <strong>the</strong> bidirus at <strong>the</strong> margin of <strong>the</strong> glade. In any case, <strong>the</strong> source must be<br />
looked after by c<strong>on</strong>stant cleaning and draining. Dry horas that are filled with sediments, like Ataui,<br />
can be occasi<strong>on</strong>ally used by excavating small wells that reach <strong>the</strong> shallow water table.<br />
<str<strong>on</strong>g>Walia</str<strong>on</strong>g>-<str<strong>on</strong>g>Special</str<strong>on</strong>g> <str<strong>on</strong>g>Editi<strong>on</strong></str<strong>on</strong>g> <strong>on</strong> <strong>the</strong> <strong>Bale</strong> <strong>Mountains</strong> 232