Document Type : Original Article
Authors
1
Environmental Research Department, Theodor Bilharz Research Institute, Giza, Egypt
2
Medical Malacology Department, Theodor Bilharz Research Institute, Imbaba, Giza, Egypt
3
Medical Malacology Department, Theodor Bilharz Research Institute, Giza, Egypt
Abstract
Macroinvertebrates are valuable surrogates in reflecting the health of river streams through their abundance, taxa richness (TR), and functional feeding groups. The present work aimed at monitoring the water quality (WQ) of the River Nile in the greater Cairo area, the most crowded with multiple human activities, using a combined approach of some physical parameters, metals, and macroinvertebrates matrices during four successive seasons. Results showed that all physical water parameters and metals were approximately at the normal levels (except temperature & Cu). The highest TR was in spring and was consistent with the low average of organic pollution determined by the Hilsenhoff biotic index (HBI), reflecting fair WQ. In contrast, the lowest abundance during winter was consistent with the highest HBI, indicating a poor WQ. Multimetric macroinvertebrates index flanders showed poor WQ during winter, while moderate WQ was observed during the rest three seasons. Filtering collectors and scrapers were the predominant functional feeding groups (FFGs), then predators at lower abundance. Gathering collectors were absent during winter, while shredders were absent in all seasons. The matrix plot showed a strong positive correlation between all FFGs and Fe, Zn, and Ca, while it showed a negative correlation with Cu. Analysis of stream ecological health matrices showed that the Nile stream was autotrophic during spring and winter, while a natural predator-to-prey was balanced during autumn, spring, and summer. Indices of habitat stability and filtering collectors pointed to perfect stable substrates only during autumn, spring, and summer, when most feeding groups were represented.
Keywords
)
View on SCiNiTO