| dc.description.abstract |
The study was conducted in the Zarima River between March and July 2023. The objectives of
the study were to assess the ecological health of Zarima River using macroinvertebrates, fish
community, and physicochemical parameters and determine the length-weight relationship the
most dominant fish species. Physicochemical sampling were collected using in situ multi
parameter probe. Macroinvertebrate specimens were collected using a D-shaped sweep net with
a mesh size of 500 µm. Gillnets with diff erent mesh sizes 6, 8 and 10 cm and monofilament nets
of various mesh sizes(4 and 6 cm) were used to collect fish specimens in both dry and wet
seasons. Immediately after capture, the total length(TL), forked length and total weight(TW)of
each individual were measured in centimeters and grams, respectively, and their relationship
was determined using the power function. A one-way ANOVA and independent t-test were used
to describe the mean difference and statistical difference in physicochemical parameters across
the sampling sites and seasons respectively. Moreover, canonical correspondence
analysis(CCA)was used to visually display patterns in macroinvertebrate and fish distribution in
relation to their environmental variables. Also, a principal component analysis was run to
ordinate sampling sites in relation to the distribution of macroinvertebrate and fish communities.
A total of 292 macroinvertebrate and 253 individual fishes were collected. While Gomphidae
was the most dominant(67.47%) taxon among the macroinvertebrates, Cyprinidae was the bestrepresented
family
of
fishes.
Zarima
River
had higher diversity(H'=1.22)
of
fish
in
dry
season
but
lower
in
wet
season
which
was(H'=0.97).
Likewise, L. intermedius was the top(88.1%) in Index
of Relative Importance value, indicating its influence in terms of number, weight, and frequency
of occurrence in Zarima River. Furthermore, the length-weight relationship for the most
abundant species showed that the relationship was strong by discussing the b-value for Garra
species(b=3.1015)attain positive allometric growth. However Labeobarbus intermedius and
Labeo forskalii attain negative allometric growth. The Zarima River’s diverse aquatic
ecosystem, influenced by seasonal and environmental factors, to recommend it need regularly
monitor the river's water quality macroinvertebrates and fish populations across different
seasons to track changes and respond to potential stressors. |
en_US |