International Journal of Aquaculture, 2016, Vol.6, No.22, 1
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physical measurements used in evaluating water quality provide data that primary reflect conditions that exist
when the water sample was taken (Muralidharan et al., 2010).
There are several research works on the pollution status of the Wurukum Abattoir. Akaahan et al. (2014) have
reported on the macroinvertebrates fauna group and their relationship with environmental variables in river Benue
where the Wurukum abattoir was a sampling station. This study approaches the research from the concept of
Abundance-Biomass Comparison (Warwick, 1986) under the assumption that in pollution conditions, numbers of
individual of species (abundance) will be more evenly distributed than biomass distributions as induced
disturbance by the pollutants.
2 Experimental Details
Study Area
River Benue with its source from the Cameroonian mountains flows eastwards into Nigeria. It is the second
largest river in Nigeria and measures approximately about 1.488 km
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with alluvia fertile flood plains in on either
bank. The River flows through Makurdi and confluence in with River Niger in Kogi state, Nigeria. Makurdi the
capital city of Benue is located on latitude 7°41'N and longitude 8°28'E.the size of the River Benue within
Makurdi and major settlement runs through is approximately 671 meters (Udo, 1981). Wurukum Abattoir is
located at the bank of River Benue and close to New Bridge that links the north and southern parts of Makurdi
Township. The Benue River at this point receives effluent from the abattoir waste which are washed directory into
the River.
Sampling was carried out weekly for a period of four months (November, 2015 - February, 2016) at four stations
selected along River Benue near the WurukumAbattoir as follows (Figure 1):
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Station A: was located at the point above the abattoir from the direction of flow i.e. close to the New
Bridge
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Station B: was located at a point where waste from the abattoir is discharged directly into the channel
adjacent to the river. This station receives a wash down of the abattoir effluent.
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Station C: was located at the point where the channel joined the main river.
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Station D: was located at a point on the main river near the Old Bridge and 50 meters from station C.
Figure 1 Map showing the study area
Sample Collection
Water samples were for physicochemical analyses were collected and analysed for temperature (in situ using
mercury in glass thermometer) while total dissolved solids (TDS), electrical conductivity (EC), and pH were
analysed in the laboratory using HANA1893 digital metal. Dissolved oxygen (DO), biochemical oxygen demand
(BOD) and Alkalinity were examined in the laboratory using standard methods (APHA, 1992).
Macroinvertebrates were collected using a van Veen grab (0.1 m
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). Each of the sediment sample collected wash
three times in the laboratory through three sets of sieves. First 2 mm, then 1 mm and finally 0.5 mm sieves to
