Belhiouani H, El-Hadef El-Okki M, Afri-Mehennaoui FZ, Sahli L. 2019. Terrestrial gastropod diversity, distribution and abundance in areas with and without anthropogenic disturbances. Biodiversitas 20: 243-249. The objective of this study was to establish an inventory of terrestrial gastropods from different sites in the northeast of Algeria. Several points were sampled from five various areas relatively affected by human activity. Areas prospected were an industrial area (El-Hadjar, Annaba), a mining area (Djebel Hamimat, Oum-El-Bouaghi), an urban area (B’kira, Constantine), a mountainous area (Ibn Ziad, Constantine) and a sub-mountainous area (Ibn Badis, Constantine). A total of 11 species and 2632 individual land snails belonging to six molluscan families (Helicidae, Hygromiidae, Sphincterochilidae, Achatinidae, Enidae, and Pomatiidae) and 10 genera were found in all habitats. The highest density was recorded in the mountainous area with 1270 individuals and 10 species, whereas the lowest value was recorded in the mining and the industrial areas with 3 and 4 species respectively. The malacofaunal diversity was also determined, Shannon’s index, Simpson’s index, and equitability index are higher in the mountainous zone of Ibn Ziad with 1.87, 0.82 and 0.78 respectively, and lower in the mining area of Djebel Hamimat, with 0.60, 0.33, and 0.54. The dispersion and density of species appear to be contingent upon several factors among which soil properties, height, climate conditions and certainly anthropogenic disturbance.
This study sought to assess sediment contamination by trace metals (cadmium, chromium, cobalt, copper, manganese, nickel, lead and zinc), to localize contaminated sites and to identify environmental risk for aquatic organisms in Wadis of Kebir Rhumel basin in the Northeast of Algeria. Water and surficial sediments (0-5 cm) were sampled in winter, spring, summer and autumn from 37 sites along permanent Wadis of the Kebir Rhumel basin. Sediment trace metal contents were measured by Flame Atomic Absorption Spectroscopy. Trace metals median concentrations in sediments followed a decreasing order: Mn > Zn > Pb > Cr > Cu > Ni > Co > Cd. Extreme values (dry weights) of the trace metals are as follows: 0.6-3.4 microg/g for Cd, 10-216 microg/g for Cr, 9-446 microg/g for Cu, 3-20 microg/g for Co, 105-576 microg/g for Mn, 10-46 microg/g for Ni, 11-167 microg/g for Pb, and 38-641 microg/g for Zn. According to world natural concentrations, all sediments collected were considered as contaminated by one or more elements. Comparing measured concentrations with American guidelines (Threshold Effect Level: TEL and Probable Effect Level: PEL) showed that biological effects could be occasionally observed for cadmium, chromium, lead and nickel levels but frequently observed for copper and zinc levels. Sediment quality was shown to be excellent for cobalt and manganese but medium to bad for cadmium, chromium, copper, lead, nickel and zinc regardless of sites.
The objectives of this study are to use different approaches to assess the current pollution status in the wadis of the Kebir Rhumel basin. First, sediment trace metal contents were measured by flame atomic absorption spectroscopy. Then, sediment quality was assessed on the basis of contamination assessment indexes such as: Geoaccumulation Index (Igeo), Contamination factor (C(f)), Contamination degree (C(d)), Sediment Pollution Index (SPI) and SEQ guidelines (Consensus Sediment Quality Guidelines). In addition, several toxicity tests (Daphnia magna mobility inhibition acute test-48 h, Aliivibrio fischeri luminescence inhibition acute test - 15/30 mn and Pseudokirchneriella subcapitata growth inhibition chronic test - 72 h) were conducted to assess sediment pore water ecotoxicity. Trace metal concentrations followed the order: Mn > Zn > Pb > Cr > Cu > Ni > Co > Cd. Indexes used indicate varying degrees of sediment quality. Igeo, C(f), C(d) and SPI reveal a polymetallic contamination dominated by two or more elements in which Cd, Cu and Pb are of greatest concern. SEQ guidelines showed that biological effects on fauna would likely be observed occasionally and/or frequently for Cd, Cr, Cu, Pb and Zn contents. Test organisms exposed to sediment pore water showed that the algal P. subcapitata test was more sensitive than the D. magna and A. fischeri tests. Hence, algal growth inhibition proved to be the most sensitive response to contaminants present in sediment extracts but a significant relationship with trace metal contents was not demonstrated.
Background: Gliomas are a relatively rare group of tumors with a poor prognosis. We aimed to describe and analyze the clinical characteristics and survival of patients with glioma tumors of Eastern Algeria. Methods: A retrospective study was conducted at the University Hospital of Constantine. Medical records of patients enrolled between January 2008 and October 2016 were consulted. Demographic characteristics, clinical data, treatment strategy and dates of last follow-up or death were collected. Chi-square test was used for checking associations, Kaplan- Meier methodology for estimating the survival, and the cox model for identifying prognosis factors. Results: A total of 333 patients composed our cohort. The mean age was 48.07 years, and men were 1.87 times more frequent than women. High grade tumors were mainly observed among adults and old adults and in supra-tentorial locations. More than half of the patients had a large resection and a curative protocol of oncological treatment (50.7% and 57%, re- spectively). The mean overall survival was 45.4 months, the median was 21.7 months, and survival rates at 1-, 2-, and 5-years were: 62.8%, 48.5% and 32.9% respectively. Age, histology, grade of malignancy and oncological treatment were the major prognosis factors. Conclusion: Our sample was relatively young with a higher survival compared to others. Keywords: Glioma; epidemiology; Algeria.
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