Response of Macroinvertebrates to Changes in Stream Flow and Habitat Conditions in Dinki Watershed, Central Highlands of Ethiopia

Highlights

• Stream conditions significantly affect macroinvertebrate assemblages.
• Spates have a more drastic effect on macroinvertebrates than flow reduction.
• Stable refuge in streams helps mitigate ecological disturbances.
• Conservation of stream habitats can buffer against hydrological disturbances.

Abstract Overview

• The study investigates effects of habitat and flow alterations on macroinvertebrates in Dinki watershed.
• 86 macroinvertebrate and water composite samples collected over 25 reaches.
• Methods: MANOVA, ANOVA, PCA for assessing variations and ordination.
• Found significant spatial variation in taxa abundance across study sites.
• Both reduced flow and spates negatively impact assemblage structures.
• Forested Gedamoch sites showed higher resistance and resilience to disturbances, highlighting importance of habitat conservation.

Methodology

• Sampling: 86 samples collected over 25 sampling reaches in multiple rounds.
• Statistical Analyses:
  • MANOVA for variations in taxa abundance, richness, and diversity.
  • ANOVA for differences in macroinvertebrate and environmental variables.
  • PCA for ordination relative to macroinvertebrates.

Findings

• Significant spatial variation in taxa abundance observed.
• Both reduced flow and spates decline assemblage structures.
• Gedamoch sites showed higher macroinvertebrate assemblages pre-and-post disturbances.
• Importance of stream habitat conservation for buffering hydrological disturbances.

Keywords

• Dinki, Gedamoch, Macroinvertebrate, Resistance, Resilience, Stream condition, Spate

Conclusion

• Stream habitat conservation is crucial for maintaining macroinvertebrate assemblages and buffering against ecological disturbances.
• Management strategies should focus on protecting and restoring stream conditions to enhance resilience to hydrological changes.