Study of the impact of metal and organic pollution on benthic macrofauna using multivariate analyses in coastal wetland of Reghaïa, Algeria.

In this study, we studied the impact of pollution, metallic, organic, and environmental parameters, on benthic macroinvertebrates of the Reghaïa wetland and coastal zone, which is a nature reserve located in northern Algeria and is one of the last heritage sites on the central coast of the country. To do this, multivariate methods are used. The results of the multivariate analyses clearly show the impact of metal and organic pollution on the macroinvertebrates of this wetland which is really striking; this pollution has destroyed and upset the biodiversity of the benthic macrofauna and it has led to the disappearance of several taxa. This pollution has drained this wetland of the taxonomic richness of benthic macroinvertebrates, the only taxa that have resisted are the Diptera such as Psychodidae, Ceratopogonidae, and Syrphidae.

The relationship between zooplankton community and environmental factors of Ghrib Dam in Algeria.

The effect of environmental factors on zooplankton diversity, abundance, and distribution in the Ghrib Dam water body was investigated for 2 years from June 2013 to May 2015. A total of 61 species of zooplankton were recorded, including 45 rotifers, 13 cladocerans, and 3 copepods. The zooplankton abundance fluctuated between 4 and 3363 ind.L-1, and its Shannon-Wiener index of zooplankton diversity in Ghrib Dam varied from H' = 1.15 to 3.77 during the 2-year study period. The highest diversity index was recorded at sampling site S1 in January 2015, due to the increase of specific richness (Ni = 27, Dmg = 5.75). Canonical correspondence analysis (CCA) was used to determine the influence of environmental factors in structuring the zooplankton species for each group. The results of CCA revealed that the most significant environmental factors influencing zooplankton community were water temperature (WT), dissolved oxygen (DO), phosphorus (PO4-), and NO3- (p < 0.05, Monte Carlo permutation test). Meanwhile, the appearance of Hexarthra sp., Collotheca pelagica, and Diaphanosoma brachyurum indicated a rise in WT. The existence of Filinia longiseta, Keratella quadrata, and Cyclops strenuus correlated with a rising of DO. Brachionus urceolaris, Filinia passa, Keratella tecta, Notholca acuminata, and Polyarthra dolichoptera positively coexisted in an increased PO4-. Daphnia longispina and Oxyurella tenuicaudis were positively associated with high concentration of NO3-.

Evaluation of the surface water quality in the Kebir-Rhumel catchment area (northeast Algeria) using biotic indices and physico-chemical analyses.

Assessing the water quality of the Kebir-Rhumel watershed by the use of benthic macroinvertebrates and physico-chemical analysis is the aim of this work. Thirteen physicochemical parameters and macroinvertebrates fauna were collected monthly in 15 stations located along the catchment area in the two principal wadis: El Kebir and Rhumel. Canonical correspondence analysis was used to study the relationships between physico-chemical parameters and macroinvertebrates. Biotic indices Biological Monitoring Working Party (BMWP'), Global Biological Normalized Index (IBGN), EPT index (Ephemeroptera, Plecoptera, Trichoptera), and %EPT/Chironomidae, based on benthic macroinvertebrates, have been applied in assessing the biological water quality. According to the results, a majority of the physicochemical parameters measured during the study period show spatial heterogeneity (Kruskal-Wallis, P value < 0.05), indicating that Rhumel wadi is more polluted compared with El Kebir wadi; the NO2-, NO3-, PO4-3, Cl-, and SM contents are very high consequences of human and industrial anthropogenic actions. Canonical correspondence analysis has shown that the environmental parameters measured during this study influence the dynamics of macroinvertebrates, and the polluo-resistant taxa (Chironomidae) predominate in sites very rich in organic matter with low oxygen conditions. Sensitive taxa have a vulnerability to pollution. The biotic indices used confirm the diagnosis of the physicochemical analysis demonstrating a very degraded quality at Rhumel wadi. The EPT index and %EPT/Chironomidae results are closer to the scores of the BMWP' index.

Evaluation of the trophic status in three reservoirs in Algeria (north west) using physicochemical analysis and rotifers structure.

The aim of this study is to examine the trophic state of three reservoirs located in the northwest of Algeria based on the physicochemistry of water and the community of rotifers. The measurements of the physicochemical variables were carried out monthly over a 2-year period from December 2015 to November 2017. The rotifers were sampled simultaneously. Abiotic and biotic indices such as the Carlson index, QB/T, and TSIROT were determined in order to classify the three reservoirs according to their trophic state. Thus, the diversity indices of Shannon-Wiener (H'), Margalef richness index (D), Pielou evenness (J'), and the density were calculated in order to study the structure of the rotifers. The Kruskal-Wallis test confirmed the heterogeneity of the physicochemical quality (P value < 0.05) among the three reservoirs. A total of 71 species were identified during this study. The result of the various indices affirms this heterogeneity and indicates a trophic state hypereutrophic for the Hammam Boughrara reservoir, eutrophic for the Bakhadda reservoir and meso-oligotrophic for Sidi Yacoub. The use of canonical correspondence analysis (CCA) has shown that the structure of rotifers is influenced by local environmental factors. Some species such as the genus Brachionus species have shown their preference for extreme conditions. The use of biotic indices is highly recommended for the trophic state evaluation of reservoirs for a better water resources management.

Correction to: Evaluation of the surface water quality in the Kebir-Rhumel catchment area (Northeast Algeria) using biotic indices and physico-chemical analyses.

The correct title is presented in this paper.