Journal of Interior Designing and Regional Planning Volume 4 Issue 1 Effects of the Macro-Invertebrates Community structure On the Quality of Surface Water in Enugu Urban, Enugu State, Nigeria 1Mr. Nnachi Michael Ama, 2Prof. Essaghah .A, 3Dr. Virginia Delunzu-Okwu, 4Dr. Ubani Obinna. J 1Lecturer Department of Urban & Regional Planning, Enugu State University of Science &Technology, Enugu 2Professor Department of Urban & Regional Plannin, Enugu State University of Science &Technology, Enugu 3Ph.D holder Department of Urban & Regional Planning, Enugu State University of Science &Technology, Enugu 4Lecturer Department of Urban & Regional Planning, University of Nigeria, Enugu Campus, Enugu Email: [email protected] Abstract The need for a robust understanding of macro invertebrates’ diversity can lead to specific management of surface water. This is essential due to frequent threats to aquatic ecosystem. The thrust of this study was to examine the water quality assessment using macro- invertebrates in surface waters in Enugu urban. In this study, 12 surface water samples were collected from the six major rivers in Enugu urban. Macro invertebrates were collected using semi-quantitative sampling techniques.The study spanned both the dry (February –early April) and the wet seasons, (late April to September). Nine (9) taxa comprising of 33 species belonging to Arthropod, Annelida and Mollusca were identified accounted for 1163 individuals. Increasing dominance of Macro-invertebrates followed the order: Mollusca (35%), Coeloptera (28%), Diptera (12.7%), Annelida (11.4%), Trichoptera (4.96%), Placoptera (2.78%), Ephemeroptera (3%), Hemiptera (0.85%) and Odonata (0.08%). The low number of macro-invertebrates and the dominant species (Melanoides, tuberculataandChironomussp.) being pollution tolerant suggest that the rivers especially Ekulu and Asata is relatively under stress. Species diversity indices showed a variation in the community structure in the rivers. Therefore, there is a need to regularly monitor and control the source of pollutants to the water bodies. Keywords: Macro-invertebrates, physicochemical parameters, Pollution, Water quality INTRODUCTION natural pressures encountered by aquatic In Nigeria, most cities contain a number of and terrestrial organisms in their habitats, water bodies together with a small network human activities do generate other more of streams. Enugu urban is among the environmental pressures. However, in cities that is have many surface water; order to understand the status of surface these rivers are linked to one another water quality and reduce pollution rate in across neighborhood’s. Among the surface surface waters, the knowledge about the water bodies are Ekulu River, Asata River, health status of aquatic environment New Haven River, Agangwu (around Coal including their biodiversity is important. Camp area), Okwuosa River, Idaw River This is robust when assessed along the and Ogbete River. [1]. Most of these seasonal and spatial variability of the freshwater ecosystems are prone to water body [2]. This can be done, aside the pollution loads from different pollution physico-chemical parameters, by using points. Though there are many sources of various established bio indicators of water 34 Page 34-42 © MAT Journals 2019. All Rights Reserved Journal of Interior Designing and Regional Planning Volume 4 Issue 1 quality. Many developed countries such as monitoring of water quality. Eliasl et al., in Europe, Canada and United States have [4] have posited that macro invertebrate grossly used macro invertebrates as bio may be suitable for assessment of severity indicators in technical standards of water of contamination of water pollution and quality monitoring [3]. In developing that these families are very diverse, countries such as Nigeria, their use is still sensitive, population to pollution of a very limited. Unfortunately, studies in water body. The study equally asserted surface water pollution have not paid that the variation in the number of these sufficient attention to the relationship macro invertebrate populations in water between spatial and temporal variation and body indicates pollution, presence of stress the diversity of macro-invertebrates in factors and damage to the ecosystem. rivers have been lacking in Nigeria at large Several studies have found the and Enugu in particular. Assessment of discrepancies of data between chemical surface water quality in Nigeria even in and biological measures [5, 6]. Studies Enugu urban was mainly done by have submitted that the assessment of the analyzing physico-chemical parameters. relative impact of water pollution on living Unlike the physico-chemical variables organisms inhabiting in surface water can which provide information about water be extensively done by bio-monitoring of quality at the time of measurement, the streams. Freshwater organisms live monitoring of living organisms (bio continuously in the water and sensitive to monitoring) can provide information about all environmental stressors [7]. However, past and/or episodic pollution and the physical and chemical assessment is not cumulative effects of a suite of watershed enough to explain the quality of water impacts. This type of comprehensive because physical and chemical parameters assessment of water quality is lacking in cannot provide long-term pollution [8]. the body of academic knowledge in Nigeria let alone in Enugu. There is no Biological monitoring has advantages over information on the structure and functioning of macro invertebrate’s chemical monitoring because it integrates species and taxa in surface water in Enugu responses to a range of pollutants urban, also no assessment of water quality occurring over different times [9]. A using macro invertebrates has been done in macro invertebrate serves a pivotal role to these rivers in Enugu urban. Against this understand ecological status of water body background, the purpose of this study is using biological indicator as a tool and assessing the macro-invertebrates provide accurate measures of stream parameters of the surface water in Enugu health. Studies have shown that out of the urban. Enugu State, Nigeria. The outcome various organisms that are prevalently of the study to give a better understanding used as biological indicators, benthic of the ecology of the surface water to macro invertebrates have always been ensure proper management and used. This is due to: the relatively low conservation of freshwater mobility and long life cycles, secondly, benthic macro invertebrates always reflect LITERATURE REVIEW temporal patterns and local conditions. It Macro invertebrates are organisms which has been posited also that invertebrates are are large enough to be seen with the subsets an aquatic environment and they unaided eye and without vertebral column, are of ecological and aquatic importance most abundant and diverse group of as they maintain various levels of inter- animals found in freshwater which include action between the community and the flies, Snails, mussels, worms, nematodes environment [10]. and crustaceans are used for bio 35 Page 34-42 © MAT Journals 2019. All Rights Reserved Journal of Interior Designing and Regional Planning Volume 4 Issue 1 They are significant within the food chain depicts the map of Enugu showing the as larger animals such as fish and birds various neighborhoods and Core Rivers in the rely on them as a food source. Macro study area. A small portion of Enugu water invertebrates are sensitive to different supply currently comes from boreholes of the th chemical and physical conditions. 9 Mile Corner water scheme. In the study area, the borehole specific capacity of 410 STUDY AREA liters/hour/meter of draw down can be The Enugu Urban area is bounded to the expected. The depths of an average borehole West by Ngwosettlement in Udi Local are generally about 110 meters. It lies in Government Area, in the East by Nkanu East transitional-savanna region; and this is Local Government Area, in the North by derived from prolonged cultivation. It is Enugu East Local Government Area and in important to know that rivers in the study the South by Nkanu West Local Government area are linked to one another across some Area. Enugu urban is located at the neighbourhoods. In other words, some of transitional-savanna region. The 2006 them are tributaries of others as they move National Population Census of Enugu was along neighbourhoods. From the geological 722, 644, according to (National Population map of Enugu, Ekulu River is the largest Commission, (NPC), 2007). Using 2.8% river that cuts across the study area; other annual rate of increase, the populations’ rivers in the study area include Asata River, projections of people that consume water in Aria River, Ikiriki River, Idaw River and the sample areas is about 873, 043. Figure 1 Ogbete River. Figure 1: Map of Enugu Enugu Urban Source: produced from Geographical Information system GIS (Quick bird Satellite imagery 2018) 36 Page 34-42 © MAT Journals 2019. All Rights Reserved Journal of Interior Designing and Regional Planning Volume 4 Issue 1 METHODS AND MATERIALS they are Ekulu river, Asata river, Aria This study adopted the experimental river, Ikiriki river, Idaw River and research method. The surface water Ogbete river. Their locations, depths, sampled in the study were all the six stations and reach was shown in table 1 major surface water in Enugu urban and below Table 1: Description of the sample location s/n Station Sample Locations Latitude Longitude Depth (m) Reach 1. S1 Ekulu River at New market fly over 331160 15126 1.67 Upper 2. S2 Ekulu River at Ujodo development centre 332483 715284 1.83 Lower Asata River at Enugu Port-Harcourt 3. S3 338568 71323 0.98 Upper Express Way, New Artisan 4. S4 Asata River at Amigo Lane CIC. 335499 713803 1.32 Lower 5. S5 Aria River at Works Road 332125 713009 1.55 Upper Aria River at Access Bank, Garden 6. S6 333501 713578 0.91 Lower Avenue 7. S7 Idaw River at Maryland, Timber Shed 334454 709239 2.10 Upper 8. S8 Idaw River at Abalukwu Street 33335 709384 2.34 Lower Ikiriki River at Enugu Port-Harcourt 9.