Abstract
Urban pollution of riverine ecosystem is a serious concern in the Niger Delta region of Nigeria. No biomonitoring tool exists for the routine monitoring of effects of urban pollution on riverine systems within the region. Therefore, the aim of this study was to develop and apply a macroinvertebrate‐based multimetric index for assessing water quality condition of impacted urban river systems in the Niger Delta region of Nigeria. Macroinvertebrate and physicochemical samples were collected from 11 stations in eight river systems. Based on the physicochemical variables, the stations were categorized into three impact categories namely least impacted stations (LIS), moderately impacted stations (MIS) and heavily impacted stations (HIS). Seventy‐seven (77) candidate metrics were tested and only five: Hemiptera abundance, %Coleoptera + Hemiptera, %Chironomidae + Oligochaeta, Evenness index and Logarithm of relative abundance of very large body size (>40–80 mm) were retained and integrated into the final Niger Delta urban multimetric index (MINDU). The validation dataset showed a correspondence of 83.3% between the index result and the physicochemically‐based classification for the LIS and a 75% correspondence for the MIS. A performance of 22.2% was recorded for the HIS. The newly developed MINDU proved useful as a biomonitoring tool in the Niger Delta region of Nigeria and can thus be used by environmental managers and government officials for routine monitoring of rivers and streams subjected to urban pollution.
Highlights
In sub‐Saharan Africa, due to population increases and industri‐ alization, urbanization is increasing at an alarming rate (Parienté, 2017)
While the majority of macroinvertebrate‐based multimetric indi‐ ces are developed for general water quality (Pešić et al, 2019; Petriki et al, 2017; Stevenson et al, 2013), the intention in this study is to develop a pollution type‐specific multimetric index for assessing urban rivers water quality impairment in Nigeria
Metrics that were predicted to increase with increasing urban pol‐ lution were assigned a score of 5 if the metric value was below the upper quartile (75%) of the least impacted sta‐ tions (LIS), a score of 3 was awarded, if metric value is above the 75%, and a score of 1 is awarded, if the metric value is above the maximum value of the LIS
Summary
In sub‐Saharan Africa, due to population increases and industri‐ alization, urbanization is increasing at an alarming rate (Parienté, 2017). While there is a need for rapid urbanization to provide em‐ ployment for sub‐Saharan African growing population, the unin‐ tended consequences of such developments include the pollution and degradation of freshwater ecosystems. The consequences of such pollution include deteriorating water quality, impaired ecologi‐ cal conditions and overall functionality of impacted urban rivers and streams (Edegbene, Arimoro, Odoh, & Ogidiaka, 2015; Edegbene, Elakhame, Arimoro, Osimen, & Odume, 2019; Gieswein, Hering, & Lorens, 2019; Mereta, Boets, Meester, & Goethals, 2013). Despite the growing urban pol‐ lution in the Niger Delta region, no biomonitoring tool exists for as‐ sessing and monitoring the extent of the effects of urban pollution on riverine ecosystems. The development of an appropriate biomon‐ itoring tool can contribute to managing pollution through effectively monitoring and assessing urban pollution effects on riverine biota
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
