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A framework for establishing a distributed, daily-time-step water resources model based on a pre-existing spatially lumped monthly representation: A case study of the Grootdraai Catchment, South Africa

  • Authors: Lazar, Sophia , Slaughter, Andrew , Griffin, Neil , Odume, Oghenekaro N
  • Date: 2025
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/486391 , vital:79501 , xlink:href="https://doi.org/10.1016/j.ejrh.2025.102493"
  • Description: Proprietary monthly lumped models are pragmatic tools for water resources management and planning. However, their low spatial granularity and limited transparency pose significant obstacles to effective water quantity and quality management, particularly in developing countries. This study aimed to develop a distributed, daily-time-step model for a developing country catchment based on an existing black-box, lumped, monthly representation.
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  • Date Issued: 2025

Macroinvertebrate colonisation of macroplastic litter in minimally disturbed river sites, Eastern Cape, South Africa

  • Authors: Ali, Andrew A , Akamagwuna, Frank C , Nnadozie, Chika F , Odume, Oghenekaro N
  • Date: 2025
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484474 , vital:78916 , https://doi.org/10.1007/s10452-024-10159-6
  • Description: Macroplastic pollution remains a growing global environmental concern, and our understanding of its interaction with aquatic organisms is underdeveloped. It is also less clear how hydraulic biotopes influence macroinvertebrates colonisation of macroplastic relative to natural substrates. We investigated temporal and spatial patterns of macroinvertebrate colonisation on macroplastic litters in contrasting stream hydraulic biotopes (riffle, pool, and run) in minimally impacted headwater streams of Eastern Cape, South Africa. Plastic substrates of different proportions of natural and plastic litter were deployed across four sites. The Substrate group included 100% natural substrates (NS), 50% natural material and 50% plastic litters (NP), and 100% plastic (PD) litters. Each substrate group was deployed in riffle, pool, and run habitats for six months at each site.
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  • Date Issued: 2025

Occurrence and distribution of microplastics in functionally delineated hydraulic zones in selected Rivers, Eastern Cape, South Africa

  • Authors: Owowenu, Enahora K , Nnadozie, Chika F , Akamagwuna, Frank C , Siwe-Noundou, Xavier , Odume, Oghenekaro N
  • Date: 2025
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/486608 , vital:79526 , xlink:href="https://doi.org/10.1016/j.envpol.2025.126544"
  • Description: Microplastic pollution in freshwater ecosystems has garnered increasing attention due to its ecological risks and potential impacts on human health. While numerous studies have addressed microplastic prevalence in rivers, a critical gap remains in understanding their spatial distribution within the geomorphological and hydraulic structure of river channels. This study investigated the occurrence and variability of microplastics across hydraulic units in two urban river systems, the Buffalo and Swartkops Rivers, in the Eastern Cape Province of South Africa. Hydraulic units were categorised into flush (riffles and runs) and sink (pools and backwaters) hydraulic zones, based on in situ measurements of flow velocity, depth, and substrate composition. Flush zones were hypothesised to promote microplastic remobilisation due to higher flow energy, whereas sink zones were expected to favour microplastic deposition owing to reduced hydraulic energy. Samples of surface water (suspended microplastics) and sediment-water mixtures (settled, then resuspended microplastics) were collected across these units in both the wet/hot and dry/cold seasons.
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  • Date Issued: 2025

Trends and geographic distribution of bacterial zoonoses in veterinary cases in the Eastern Cape: A ten-year retrospective analysis

  • Authors: Nnadozie, Chika F , Odume, Oghenekaro N
  • Date: 2025
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484518 , vital:78920 , https://doi.org/10.1016/j.jiph.2025.102738
  • Description: Diseases affecting livestock can have ripple effects on surrounding ecosystems, especially by contaminating water sources. Their occurrence poses significant public health issues, especially in areas such as the Eastern Cape province in South Africa, susceptible to climatic variations and where people and animals often share water sources, increasing the risk of transmission of waterborne zoonoses. Waterborne zoonoses are infectious diseases caused by zoonotic pathogens, including bacteria, viruses, protozoa, and parasitic helminths transmitted from animals through the aquatic environment to humans and vice versa. Tracking zoonoses in livestock is an early indicator of potential contamination of water sources used by animals and humans. This study analysed trends in prevalence of water-transmissible bacterial zoonoses over ten years, identifying the most frequently recorded zoonoses, their geographical distribution, and determining the animal species most commonly associated with these diseases.
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  • Date Issued: 2025

Developing an approach for balancing water use and protecting water quality of an urban river ecosystem

  • Authors: Sani, Zouera , Tshimanga, Raphael M , Odume, Oghenekaro N , Basamba, Twaha A , Katshiatshia, Haddy M
  • Date: 2024
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484529 , vital:78930 , https://doi.org/10.1016/j.pce.2024.103687
  • Description: Urban stream syndrome is a growing phenomenon in tropical part of the world. Urban rivers face significant challenges due to pollution induce by anthropogenic activities, exacerbated by population growth and industrialization. The main objective of this study is to develop a generic approach to balance water use and the protection of water quality in urban rivers. Water quality physico-chemical assessments were conducted during the dry and rainy seasons at various points along the N'Djili River and its tributaries. Anthropogenic activities in the surrounding areas were also analyzed to determine water uses from each sampling site. Sites were classified based on their pollution level using multivariate analysis and hierarchical classification into management classes.
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  • Date Issued: 2024

Perceptions and knowledge of ecosystem services in urban river systems, Eastern Cape, South Africa

  • Authors: Mack, Elizabeth A , Akamagwuna, Frank C , Murata, Chenai , Materechera-Mitochi, Fenji , Nnadozie, Chika F , Odume, Oghenekaro N
  • Date: 2024
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484496 , vital:78918 , https://doi.org/10.1007/s11252-024-01562-w
  • Description: The ecosystem services concept has been studied in rural contexts but not as much in urban landscapes, particularly for aquatic ecosystems in Africa. There is little knowledge of how people perceive ecosystem services (ES) supplied by rivers in urban centres and the factors influencing their perceptions. To fill this gap, the research presented here addresses two objectives: 1) to assess local communities’ perception and knowledge of different types of ecosystem services of an urban river in South Africa, 2) to assess the influence of particular demographic characteristics (age and gender), socio-economic characteristics (education, housing type, income, and years of residence), and prior knowledge of the ecosystem services concept on people’s perception of the ecosystem services provided by the Swartkops River in the Eastern Cape of South Africa. To address these objectives, a team of ten trained field staff collected 181 surveys between May–June 2021 in communities within the river catchment. We used multinomial logit models to analyse the relationships between demographic and socio-economic variables, and people’s perception of ecosystem services.
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  • Date Issued: 2024

Relationship between land use and water quality in a tropical urban catchment of the Congo Basin: A case study of N'Djili River catchment

  • Authors: Sani, Zouera , Katshiatshia, Haddy M , Tshimanga, Raphael M , Basamba, Twaha A , Odume, Oghenekaro N
  • Date: 2024
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484540 , vital:78931 , https://doi.org/10.2166/wpt.2024.080
  • Description: This study focuses on N'Djili River catchment, a vital water source in Kinshasa that undergoes anthropogenic pressure and land use changes. The lower course of the river is particularly affected by uncontrolled urbanization, informal settlements, improper waste management practices, and vegetation degradation. The aim of this study is to determine the relationship between land use and river water quality in this catchment. Water samples were collected for physico-chemical and bacteriological analysis from 10 sampling sites along the river course. Land use categories were determined using Sentinel-2 land cover imageries and buffer scaling techniques. A redundancy analysis (RDA) was conducted to determine the relationship between land use categories and water quality variables.
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  • Date Issued: 2024

Spatiotemporal variations in the occurrence of Campylobacter species in the Bloukrans and Swartkops rivers, Eastern Cape, South Africa

  • Authors: Chibwe, Mary , Odume, Oghenekaro N , Nnadozie, Chika F
  • Date: 2024
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484507 , vital:78919 , 10.1016/j.heliyon.2024.e28774
  • Description: An increase in the incidence of Campylobacter species in rivers raises concerns on the safety of river water for humans who get exposed to river water. This study examines the spatiotemporal dynamics of Campylobacter species in the Bloukrans and Swartkops rivers, analysing patterns of its occurrence in relation to meteorological conditions, physicochemical parameters, seasons, and sampling sites. Physico-chemical parameters and meteorological conditions were measured during water sampling from various sites along the rivers over a year, while Polymerase Chain Reaction (PCR) was utilised to detect Campylobacter genus-specific genes and selected antibiotic-resistant genes.
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  • Date Issued: 2024

Stakeholder contestations of water quality use and management in the Vaal Barrage catchment

  • Authors: Odume, Oghenekaro N , Chili, Asanda , Nnadozie, Chika F , Slaughter, Andrew R
  • Date: 2024
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/480606 , vital:78459 , https://hdl.handle.net/10520/ejc-sajsci-v120-n9-a18
  • Description: The water resources within the lower section of the Upper Vaal catchment, where the Vaal Barrage is situated, are highly utilised and developed, and water quality regulation has become a contested space between resource users and the regulators. The credibility and scientific defensibility of discharge standards in water-use licences (WULs), the relationship between upstream and downstream waste loads, the relationship between flows and water quality standards in WUL, and the water quality components of the resource quality objectives (RQOs) are being contested. This study explores the perceptions and motivations underlying these contestations as a contribution to scientific understanding of water quality management in a highly developed system. Perceived unrealistic RQOs, perceived lack of scientific credibility of the methods for deriving water quality standards in WUL, data inadequacy, as well as poor institutional capacity were identified as the top motivations for contesting applicable regulatory instruments in the catchment. Punitive measures, incentives, and education and awareness-raising were identified as key to accelerating compliance. Overall, this paper contributes to our general understanding of the intricacies of water quality management within a contested space.
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  • Date Issued: 2024

A critical review of environmental factors influencing the transport dynamics of microplastics in riverine systems: implications for ecological studies

  • Authors: Owowenu, Enahora K , Nnadozie, Chika F , Akamagwuna, Frank C , Noundou, Xavier S , Uku, Jude E , Odume, Oghenekaro N
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484452 , vital:78907 , https://doi.org/10.1007/s10452-023-10029-7
  • Description: Microplastics (MPs) in rivers present an ecological risk. In this paper, we review hydro-geomorphological, biological, and allochthonous factors that may influence the distribution and transport of MPs in riverine systems. We also review MPs characteristics that may impact their distribution and transport. At the reach scale, hydraulic biotopes and their key features such as flow velocity, bed roughness, depth, and channel morphology are important features that shape the distribution and transport of MPs in riverine systems and should be considered in the design of MPs studies. Microbial-MPs interaction may impact MPs density, aggregation and thus transport dynamics. Instream vegetation may act as a physical trap of MPs, which may impact their horizontal transport and aggregation. Lateral transport of MPs is impacted mostly by precipitation, run-off, point and non-point discharges. The polymer density, size and shapes of MPs are critical factors that influence their transport dynamics in riverine systems. Microplastic sampling protocols should be designed to reflect hydro-geomorphological considerations. The unique interaction of MPs physical characteristics and hydraulic biotopes creates differential exposure of riverine organisms to MPs and should be used to unravel potential impacts. Biomonitoring studies should integrate the complex MPs-hydraulic interaction for ecologically meaningful investigation into organismal exposure to MPs in their preferred biotopes. Overall, our review indicates the influences of hydro-geomorphological features on the transport dynamics of MPs and their ecological significance for the study of MPs in rivers.
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  • Date Issued: 2023

A review of antibiotic resistance among Campylobacter species in human, animal, and water sources in South Africa: a One Health Approach

  • Authors: Chibwe, Mary , Odume, Oghenekaro N , Nnadozie, Chika F
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484622 , vital:78977 , https://doi.org/10.2166/wh.2022.146
  • Description: Campylobacter species are among the aetiological agents responsible for 400–500 million human diarrhoea cases per annum. The risk of dissemination of antibiotic-resistant Campylobacter species between humans, animals, and the environment is anticipated, given its transmissibility through these sources. The objective of this paper is to present a situation analysis that reports the current patterns and determinants of Campylobacter antibiotic resistance in South Africa. This review applies the One Health (OH) Approach to systematically review and collate the current antibiotic resistance status among Campylobacter spp. in South Africa.
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  • Date Issued: 2023

Agricultural disturbance affects taxonomic and functional diversity of Afrotropical macroinvertebrate composition in a South African river system

  • Authors: Akamagwuna, Frank C , Odume, Oghenekaro N , Richoux, Nicole B
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/454293 , vital:75333 , xlink:href="https://doi.org/10.1016/j.indic.2023.100251"
  • Description: Developing species-level biomonitoring tools to monitor riverine systems threatened by anthropogenic pollution, including local agricultural activities in the Afrotropical region, remain a critical challenge. Here we explored the utility of taxonomic-based (diversity, richness, and composition) as well as functional-based (functional diversity) indices to examine the effects of agricultural disturbance on macroinvertebrate communities in the Kat River, Eastern Cape Province of South Africa. We collected physicochemical parameters and macroinvertebrates from eight sites delineated into four land-use categories (highly impacted, HIC; impacted category, IC; moderately impacted, MIC and least impacted, LIC) using agricultural land cover. We recorded 70 macroinvertebrate taxa belonging to 49 families and 48 genera in the Kat River. Redundancy analysis (RDA) and Pearson correlation analysis revealed that species of Lymnaeidae, Belostomatidae, Planorbidae and Libellulidae families and class Oligochaeta were tolerant to agricultural disturbance, as they were dominant in the highly impacted sites and were significantly associated with high salinity, temperature, total dissolved solids (TDS), flow velocity and nutrients. Conversely, species of Baetidae, Caenidae and Potamonautidae were negatively associated with the highly impacted sites and high salinity, temperature, and nutrients. On the other hand, taxonomic indices showed more sensitivity to indicators of agricultural pollution than functional indices, with taxon richness, Shannon index, Simpson's index and Margalef's index declining significantly in the highly disturbed sites (p less than 0.05). They were negatively associated with high electrical conductivity, large river width, and high nitrite and nitrate concentrations; hence they were identified as indicator metrics sensitive to agricultural pollution. Overall, our study revealed that agricultural disturbance could differentially affect the structure and function of macroinvertebrates, and indicator taxonomic and functional indices were identified for long-term monitoring of rivers that drain agricultural landscapes.
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  • Date Issued: 2023

Assessment of risk of exposure to Campylobacter species and their antibiotic-resistant genes from selected rivers in the eastern cape, South Africa

  • Authors: Chibwe, Mary , Odume, Oghenekaro N , Nnadozie, Chika F
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484463 , vital:78908 , https://doi.org/10.1016/j.envpol.2023.122625
  • Description: Contaminated rivers play a critical role in the transmission of Campylobacter and antibiotic-resistant genes (ARGs) in many parts of the world. South Africa is a water-scarce country which relies on its freshwater systems such as rivers for recreation, irrigation, and domestic activities. This study assesses the potential human exposure to Campylobacter and its ARGs from rivers through the ingestion route in two South African rivers. The concentration of viable Campylobacter and ARGs in selected rivers was determined using quantitative PCR. The concentrations were then used to estimate the number of gene copies a person could ingest after swimming in the contaminated water for 1 h (intake burden).
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  • Date Issued: 2023

Microplastics as vectors of chemical contaminants and biological agents in freshwater ecosystems: Current knowledge status and future perspectives

  • Authors: Tumwesigye, Edgar , Nnadozie, Chika F , Akamagwuna, Frank C , Noundou, Xavier S , Nyakairu, George W A , Odume, Oghenekaro N
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484484 , vital:78917 , https://doi.org/10.1016/j.envpol.2023.121829
  • Description: Microplastics (MPs) are becoming ubiquitous, and their environmental fate is becoming an issue of concern. Our review aims to synthesize current knowledge status and provide future perspectives regarding the vector effect of MPs for chemical contaminants and biological agents. The evidence in the literature indicates that MPs are a vector for persistent organic pollutants (POPs), metals and pharmaceuticals. Concentrations of chemical contaminant in orders of six-fold higher on MPs surfaces than in the surrounding environmental waters have been reported. Chemical pollutants such as perfluoroalkyl substances (PAFSs), hexachlorocyclohexane (HCHs) and polycyclic aromatic hydrocarbons (PAHs), exhibiting polarities in the range of 3.3–9 are the commonest chemicals reported on MP surfaces. Regarding metals on MPs including chromium (Cr), lead (Pb), cobalt (Co), the presence of C–O and N–H in MPs promote a relatively high adsorption of these metals onto MP surfaces. Regarding pharmaceuticals, not much has been done, but a few studies indicate that commonly used drugs such as ibuprofen, ibuprofen, diclofenac, and naproxen have been associated with MPs. There is sufficient evidence supporting the claim that MPs can act as vectors for viruses, bacterial and antibiotic-resistant bacteria and genes, and MPs act to accelerate horizontal and vertical gene transfer. An area that deserves urgent attention is whether MPs can act as vectors for invertebrates and vertebrates, mainly non-native, invasive freshwater species. Despite the ecological significance of invasive biology, little research has been done in this regard. Overall, our review summarises the state of the current knowledge, identifies critical research gaps and provides perspectives for future research.
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  • Date Issued: 2023

A global agenda for advancing freshwater biodiversity research

A macroinvertebrate-based multimetric index for assessing ecological condition of forested stream sites draining Nigerian urbanizing landscapes

  • Authors: Edegbene, Augustine O , Akamagwuna, Frank C , Odume, Oghenekaro N , Arimoro, Francis O , Ovie, Tega T E , Akumabor, Ehi C , Ogidiaka, Efe , Kaine, Edike A , Nwaka, Kehi H
  • Date: 2022
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484610 , vital:78976 , https://doi.org/10.3390/su141811289
  • Description: Urban pollution is increasing at an alarming rate within the catchments of forested riverine systems in sub-Saharan Africa, Nigeria inclusive. Assessing the impact of pollution in riverine systems in the Niger Delta region is still within the use of physico-chemical variables and biota-based assemblage. In covering this important gap in freshwater biomonitoring, we developed a macroinvertebrate-based multimetric index (MMI) that would be useful in monitoring, assessing, and managing forested riverine sites affected by urban pollution. We collected macroinvertebrates and physico-chemical samples monthly at 20 sites in 11 streams. Physico-chemical variables were analysed using standard methods while a kick sampling procedure was employed in collecting macroinvertebrates. The physico-chemical variables were used to classify the sites into three disturbance categories: least-impacted sites (LIS), moderately impacted sites (MIS), and heavily impacted sites (HIS). Fifty-nine candidate macroinvertebrate metrics were selected and screened for developing our MMI. We employed sensitivity, seasonality, repeatability and redundancy tests, and metric scoring in screening and arriving at the final metrics for the MMI development. Five metrics were finally selected for the MMI development: Trichoptera abundance, %Chironomidae+Oligochaeta, Coleoptera richness, Simpson diversity, and Shannon–Wiener index.
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  • Date Issued: 2022

Exploring the community structure of Afrotropical macroinvertebrate traits and ecological preferences along an agricultural pollution gradient in the Kat River, Eastern Cape, South Africa

  • Authors: Akamagwuna, Frank C , Odume, Oghenekaro N , Richoux, Nicole B
  • Date: 2022
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/454334 , vital:75336 , xlink:href="https://doi.org/10.1016/j.ecolind.2022.108570"
  • Description: Agricultural activities impact riverine ecosystem structure, function, and processes. In the Afrotropical regions, research on agricultural effects on macroinvertebrate trait distribution is sparse. In this study, we investigated the spatial and temporal changes in the community structure of macroinvertebrate traits along an agricultural disturbance gradient in an Afrotropical River system. Physicochemical variables were sampled alongside macroinvertebrates at eight sites in the dry (winter and spring) and wet (summer and autumn) periods of 2018–2019. We grouped the sites into four categories using the percentage of agricultural land-use cover within each drainage area. Our results showed that agricultural pollution exhibited varying effects on traits and ecological preferences, with traits such as a predatory lifestyle, medium body-size (>10–20 mm), active swimming, possession of spiracles and haemoglobin, and adult aquatic life stage increasing with the pollution gradient. These traits were positively associated with nutrients (PO4+-P, NO2+-N, NH4+-N and NO3+-N), salinity, turbidity and temperature and were deemed tolerant of agricultural pollution. Shredding, crawling, and a preference for macrophytes as food showed strong positive associations with the least disturbed sites and were negatively associated with increasing nutrients, salinity, turbidity and water temperature. As such, these three traits were considered sensitive to agricultural pollution. The identified indicator traits can be used to predict the survival and distribution patterns of organisms under the impact of agriculture-induced stress.
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  • Date Issued: 2022

Case Study For Linking Water Quality License Conditions With Resource Quality Objectives For The Leeutaaiboschspruit Industrial Complex Situated Within The Vaal Barrage Catchment Volume 1

  • Authors: Odume, Oghenekaro N , Slaughter, Andrew R , Griffin, Neil J , Chili, Asanda
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , report
  • Identifier: http://hdl.handle.net/10962/438074 , vital:73433 , ISBN 978-0-6392-0224-2 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/TT 838-1 final web.pdf
  • Description: In South Africa, the resource-directed measures (RDM) and the source-directed con-trols (SDC) are the two complementary strategies designed to ensure that water resources are used and protected. The RDM are directed at water resources to en-sure their protection, and include the Water Resource Classification System (WRCS), the classification of every significant water resource, the determination of the re-serve and the setting of resource quality objectives (RQOs). On the other hand, the SDC are measures imposed to restrict and control the use of water resources, not only in terms of ensuring water resource protection, but also in terms of ensuring that water resources are equitably allocated and are used efficiently. Water use li-cencing (WUL) is an example of an SDC instrument.
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  • Date Issued: 2021

Biodiversity patterns along seasonality and environmental factors of stream macroinvertebrate communities of North-Central Nigeria

  • Authors: Keke, Unique N , Arimoro, Francis O , Ayanwale, Adesola , Odume, Oghenekaro N , Edegbene, Augustine O
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/486410 , vital:79503 , xlink:href="10.21608/EJABF.2020.102102"
  • Description: While there is a substantial increase in the number of studies investigating the biodiversity of the Afrotropical region, the influence of season on biodiversity is still poorly understood. The biodiversity patterns of 15 streams along with seasonality and environmental correlates were explored from 2016 - 2017. Biodiversity variables were calculated using diversity functions in vegan, including beta diversity partitioning. Seasonal variations in biodiversity and community-environment relationships were calculated using Mann–Whitney–Wilcoxon tests and distance-based redundancy analysis (dbRDA). While alpha diversity was low, beta diversity was relatively high and promoted by its turnover component. In spite of the clear seasonal variabilities of the region, biodiversity variables did not differ between seasons, suggesting that temporal variation was not a key factor in structuring the streams macroinvertebrates. The results suggest that seasonal variations in biodiversity may be confounded by multiple factors, including possible overridden influence from the regional perspective of biodiversity. In order to establish reliable biomonitoring and conservation programs for biodiversity, studies from different seasons should be considered, especially regions rich in biodiversity.
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  • Date Issued: 2020

Ephemeroptera, Plecoptera and Trichoptera (EPT) functional feeding group responses to fine grain sediment stress in a river in the Eastern Cape, South Africa

  • Authors: Akamagwuna, Frank C , Odume, Oghenekaro N
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/486426 , vital:79504 , xlink:href="https://doi.org/10.1007/s10661-020-8187-4"
  • Description: Sedimentation arising from agricultural run-offs, riparian habitat fragmentation and channel bank erosion has long been known to impair the structure and ecological functioning of stream and river ecosystems. This study examined the effects of fine sediment grain sizes on the functional feeding group structure of Ephemeroptera, Plecoptera and Trichoptera (EPT) in the Tsitsa River catchment in the Eastern Cape Province of South Africa. Fine sediments and EPT were sampled between August 2016 and April 2017 from eight selected sampling sites. The eight sites were classified into four groups in terms of fine sediments and turbidity to represent a gradient of sediment stress, with site groups 4 and 3 being less influenced and groups 2 and 1 as the highly influenced groups. EPT genera/species were assigned to five functional feeding groups (FFGs) and their responses to sediment stress assessed.
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  • Date Issued: 2020
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