| dc.description.abstract | The study was conducted in June and September 2011 in six rivers that drain
Mt. Kenya and the Aberdare catchments, i.e. Honi, Naro Moru, Liki,
Sirimon, Mariara and Karigu. The main objective was to determine the
ecological status of these rivers and identify macroinvertebrates with
potential applicability as biomonitors. South African Scoring System version
5 (SASS-5), Multimetric Index (i.e. MI; values ranging from 0 = poor to
natural = 1) and the Qualitative Habitat Assessment (QHA) methods were
used in this study. Values more than 80% indicate largely unmodified
systems (class B and A) whilst values below 40% indicate largely modified
systems (classes, D, E and F). Class C (moderately modified systems fall
within 60 – 79%). The highest number (16) of macroinvertebrate taxa were
recorded at the Naro Moru and Mariara Rivers, while the lowest (3) was
recorded at Karigu River. Macroinvertebrate abundance differed significantly
among the rivers (One-way ANOVA, (F (5,135) = 3.533, p < 0.01). Based on
QHA, Naro Moru River could be categorized as management class B, while
the rest of the studied rivers fall under management class C. On MI basis,
Naro Moru, Liki and Sirimon Rivers were of good water quality (MI = > 0.6)
while Honi and Mariara Rivers were of moderate water quality (MI = 0.4-
0.6). Monitoring with macroinvertebrates enabled identification of
anthropogenically affected rivers and placement of the study sites in their
respective management classes for future interventions. | en_US |
