Benthic macroinvertebrates as ecological health indicators in the Luapula basin for potential inter-basin water transfer to the Kafue basin.
| dc.contributor.author | Nyambe, Nathan | |
| dc.date.accessioned | 2025-07-16T06:57:02Z | |
| dc.date.available | 2025-07-16T06:57:02Z | |
| dc.date.issued | 2025 | |
| dc.description | Thesis of the Master of Science Degree in Integrated Water Resources Management | |
| dc.description.abstract | Water scarcity is a global challenge, affecting sustainable development, human well-being and ecosystem health. In Zambia, the Kafue River Basin, an important economic and ecological resource, faces growing water demand that exceeds its natural supply and supply capacity, leading to resource allocation conflicts. In response, the government is considering inter-basin water transfers from the resource-abundant Luapula River Basin. However, such transfers could pose significant environmental risks to both basins. This study evaluated the ecological health of rivers and streams in the Luapula Basin using benthic macroinvertebrate assemblages and water quality parameters. The Luapula Basin was divided into three hydro-environmental zones using remote sensing techniques. Macroinvertebrate samples were collected from designated sites across these zones, with in situ measurements of physicochemical variables. Laboratory analyses of water samples followed APHA (1998) standards. Similarity Percentage (SIMPER) was used to assess macroinvertebrate compositional heterogeneity, the Zambia Invertebrate Scoring System (ZISS) and Shannon Diversity Index was used to evaluate river health and biodiversity and Canonical Correspondence Analysis (CCA) was employed to determine how altitude and water quality influence macroinvertebrate distribution. Seasonal and zonal variations in biodiversity, stream health and water quality were tested using multivariate and univariate ANOVA, while Pearson correlation analyses explored relationships between biodiversity attributes and health indicators. Pollution-tolerant taxa, such as Decapoda, Odonata, Gastropoda and Hemiptera, dominated the macroinvertebrate community, while sensitive Ephemeroptera families were present seasonally, especially during the wet season. SIMPER analysis indicated spatial differentiation among zones, with dry and wet season dissimilarities of 56.67% and 63.33%, respectively. Most sites were classified as moderately impaired based on ZISS scores, with a few showing major seasonal impairments. MANOVA revealed significant inter-zone differences in biodiversity and health metrics (p < 0.05), driven by ZISS scores (p < 0.05) and taxa richness (p < 0.01). Taxa richness, ZISS scores and Shannon diversity were positively correlated, while evenness correlated negatively. Functional feeding group (FFG) analysis indicated a heterotrophic system dominated by gathering collectors, predators and scrapers, with limited riparian-shredder linkages and a prevalence of polyvoltine prey populations. Water quality showed significant seasonal variations (MANOVA: p < 0.001), with ANOVA identifying turbidity, hardness, calcium, magnesium, chloride, potassium and faecal coliforms as key drivers. The water quality index highlighted iron, turbidity and faecal coliforms as major contaminants, with seasonal improvements varying by zone. CCA linked dry-season macroinvertebrate assemblages to altitude, iron, sodium, chloride, potassium, turbidity, magnesium, and hardness. In contrast, wet-season assemblages were shaped by altitude, faecal coliforms, pH, potassium, conductivity, and dissolved solids. The study concludes that the Luapula Basin experiences moderate ecological impairment, with seasonal water quality fluctuations driven by natural and anthropogenic factors. Planned water transfers risk further ecological degradation, emphasising the need for comprehensive hydrological and ecological assessments to guide sustainable resource management. | |
| dc.description.sponsorship | ` | |
| dc.identifier.uri | https://dspace.unza.zm/handle/123456789/9279 | |
| dc.language.iso | en | |
| dc.publisher | The University of Zambia | |
| dc.title | Benthic macroinvertebrates as ecological health indicators in the Luapula basin for potential inter-basin water transfer to the Kafue basin. | |
| dc.type | Thesis |