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The
hydrochemistry and macrobenthic fauna characteristics of an
urban draining creek
Clement A. Edokpayi1*, Aveez O. Olowoporoku2
and Roland E. Uwadiae1
1Department
of Marine Sciences, University of Lagos, Akoka, Yaba, Lagos
State,
Nigeria.
2University
of West of England, Bristol, United Kingdom.
*Corresponding author. E-mail:
klemedokpayi@gmail.com.
Accepted
15 March, 2010 |
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Lagos
lagoon is the largest of the eight lagoons that make up the
lagoon systems of Nigeria and probably the most exposed to
anthropogenic influence. The pollution status of the Lagos
lagoon is generally attributed to the direct discharge of
waste (domestic and industrial) and the contribution from
rivers, creeks and drainage canals that empty into the
Lagoon at different points. The paucity of information on
the pollution status of water bodies that feeds the Lagos
lagoon informed this present study. Investigation into the
hydrochemistry and benthic macrofauna of Ogbe creek that
drains through the main land of Lagos and empty into the
Lagos lagoon was carried out. Fortnightly, sample
collections between March and August 2002 at three stations
along a 2 km stretch of the creek within the University of
Lagos were used for the study. The hydrogen ion
concentration ranged from 5.4 to 9.4. The electrical
conductivity, salinity, alkalinity, nitrate, phosphate,
dissolved oxygen and biochemical oxygen demand ranged
between 3.65 ± 3.07 to 3.96 ± 3,22 Sµcm-1; 0.51 ±
0.64 and 1.01 ± 0.96 ‰; 33.3 ± 23.2 and 60 ± 32.79 mgl-1;
4.12 ± 0.17 and 7.46 ± 1.02 mgl-1; 1.93 ± 0.53
and 3.65 ± 1.02 mgl-1; 2.83 ± 1.42 and 4.65 ±
0.59 mgl-1 and 7.96 ± 1.99 and 8.13 ± 1.61 mgl-1,
respectively. The high BOD5, nitrates and
phosphates values are indicative of a perturbed environment.
A total of 246 organisms belonging to 16 benthic taxa, 13
genera, 12 families, 8 orders and 4 phyla were collected
during the study period. Chironomid larvae and the Naidid
worms were the most abundant groups. They accounted for
25.61 and 22.76%, respectively, of the total macrobenthic
count. The low number of taxa and numerical abundance of
pollution indicator macrobenthos in the study area reflected
a perturbed creek.
Key
words:
Hydrochemistry, benthos, university of Lagos, Ogbe creek,
Nigeria.
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