Benthic community ecology for Algerian river Seybouse

Abstract

The Seybouse is the second largest river basin in Algeria, hosting an important biodiversity and providing various ecosystem services. This watershed is highly influenced by agricultural and industrial activities, which threaten its biodiversity and ecosystem integrity. The use of benthic macroinvertebrates as biological indicators has a long tradition in developed countries and integrated into all assessments of the ecological quality of river systems. However, the macroinvertebrates of many North African regions are still not well studied, including those of the Seybouse river. The aim of this study is to assess the inventory and ecological role of benthic macroinvertebrates in inland waters of the Seybouse River and determine the impact of pollution on their spatial distributions. We sampled the benthic macrofauna of Wadi Seybouse and its affluents using regular surveys in three sites, of which one was in the upper Seybouse Bouhamdane in Medjez Amar and two in the middle Seybouse. Between December 2019 and May 2020, 10 physico-chemical parameters (pH, EC, OD, water speed, NO3, Salinity, NO2, MES, turbidity, depth) were measured in order to establish a health state diagnosis of these aquatic ecosystems. The complementary biological approach by the analysis of populations of macroinvertebrates identified 7482 individuals and 40 taxa divided into five classes: Crustaceans which were the most dominant, insects with the main orders (Ephemeroptera, Diptera, Trichoptera, Heteroptera and Odonata), Molluscs, Nematodes and Annelids. The physico-chemical analyzes and the application of the organic pollution indices indicated a strong to excessive pollution for all sites, especially in Seybouse upstream

Characterization and diversity of macroin-vertebrates in groundwater in the region of Souk-Ahras (North-East of Algeria)

“…Spatial (inter-site) variability in the richness of taxonomic orders was detected. Our results reveal that the majority of macroinvertebrates in the studied environments are similar to those in the temporary superficial studied habitats in Morocco (Giudicelli, Thiéry, 1998), Italy (Bazzanti et al,1996(Bazzanti et al, , 2009Bagella et al, 2010), Spain (Boix et al, 2004(Boix et al, , 2008(Boix et al, , 2009, and in Algeria (Lounaci et al, 2000;Khelifa, 2019;Khelifa et al, 2016;Meziane et al, 2020, 2022Rouibi et al, 2021). A total of 29 taxa and 1715 individuals were collected during this study.…”

“…By comparison, groundwater populations are much less diversified compared to watercourses, in particular, those of watercourses in Kabylie Djurdjura (Lounaci, 2005), Wadi Djedir and Wadi M'zi (Sellam et al, 2017), Oued Boumerzoug (Bekhouche et al, 2017), watershed of the Soummam (Zouggaghe, 2020), Oued Sybousse (Baaloudj et al, 2020(Baaloudj et al, , 2022, and Wadi Bouhamdane (Rouibi et al, 2021). Figure 6 represents the spatial distribution of taxonomic richness, which revealed variation from one well to another.…”

Distribution of benthic macroinvertebrate communities in different kind of inland water bodies in northeastern Algeria

“…It is because the water velocity decreases from upper to lower zones along river course, due topographical conditions, whereas the conductivity varies along river course due variations in nutrients and mineral inputs from surrounding basin due natural conditions (Figueroa et al, 2003;Rouibi et al, 2021). These results are like descriptions for Algerian (Chaib et al, 2023;Baaloudj et al, 2022) and Chilean rivers (De los Ríos-Escalante et al, 2020a).…”

“…The result proved by the RDA analysis, revealed water velocity, pH, turbidity, and dissolved oxygen are the most important abiotic conditioning factor for composition of benthic communities, it is due because high velocity are associated with running waters in upper zones of river course that under natural conditions have low conductivity, high pH, high oxygen level [O 2 ] and low turbidity that in consequence the environment has low productivity for that can sustain the species diversity (Baaloudj et al, 2022). The presence of high velocity water is a stressor agent that don´t allow the assessment of benthic invertebrates (De los Ríos-Escalante et al, 2020a).…”

“…The presence of high velocity water is a stressor agent that don´t allow the assessment of benthic invertebrates (De los Ríos-Escalante et al, 2020a). Whereas sites with low pH, low oxygen level [O 2 ], high turbidity, low velocity are associated with lower zones of river course with high conductivity due high nutrients and mineral concentrations due the accumulation from medium and upper zones, that in consequence generate environments with high productivity and high species abundances (Baaloudj et al, 2022). The most abundant taxa for all sites are Corixidae and Gammaridae, and the most abundances were reported mainly between February to June, that would correspond to Northern Hemisphere spring that would corresponds to the end of short-wet season (Chaib et al, 2023).…”