ENVIRONMENTAL CONTROLS ON FORAMINIFERA IN LAKE QARUN, EGYPT

Abstract

Research Article| April 01, 2007 ENVIRONMENTAL CONTROLS ON FORAMINIFERA IN LAKE QARUN, EGYPT Ramadan H. Abu-Zied; Ramadan H. Abu-Zied 3 1Geology Department, Faculty of Science, Mansoura University, El-Mansoura 35516, Egypt. 3 Correspondence author. E-mail: [e-mail] Search for other works by this author on: GSW Google Scholar Kevin W. Keatings; Kevin W. Keatings 2Environmental Change Research Centre, Department of Geography, University College London, Pearson Building, Gower Street, London WC1E 6BT, UK. Search for other works by this author on: GSW Google Scholar Roger J. Flower Roger J. Flower 2Environmental Change Research Centre, Department of Geography, University College London, Pearson Building, Gower Street, London WC1E 6BT, UK. Search for other works by this author on: GSW Google Scholar Author and Article Information Ramadan H. Abu-Zied 3 1Geology Department, Faculty of Science, Mansoura University, El-Mansoura 35516, Egypt. Kevin W. Keatings 2Environmental Change Research Centre, Department of Geography, University College London, Pearson Building, Gower Street, London WC1E 6BT, UK. Roger J. Flower 2Environmental Change Research Centre, Department of Geography, University College London, Pearson Building, Gower Street, London WC1E 6BT, UK. 3 Correspondence author. E-mail: [e-mail] Publisher: Cushman Foundation for Foraminiferal Research Received: 22 Sep 2005 Accepted: 28 Aug 2006 First Online: 03 Mar 2017 Online ISSN: 1943-264X Print ISSN: 0096-1191 © 2007 Journal of Foraminiferal Research Journal of Foraminiferal Research (2007) 37 (2): 136–149. https://doi.org/10.2113/gsjfr.37.2.136 Article history Received: 22 Sep 2005 Accepted: 28 Aug 2006 First Online: 03 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Ramadan H. Abu-Zied, Kevin W. Keatings, Roger J. Flower; ENVIRONMENTAL CONTROLS ON FORAMINIFERA IN LAKE QARUN, EGYPT. Journal of Foraminiferal Research 2007;; 37 (2): 136–149. doi: https://doi.org/10.2113/gsjfr.37.2.136 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyJournal of Foraminiferal Research Search Advanced Search Abstract Foraminifera were investigated in Lake Qarun, an Egyptian inland saltwater lake, to determine their spatial distribution and the most common environmental factors that influence this distribution. Forty surface sediment grab samples from the lake were found to be rich in benthic foraminifera. Their faunal density ranged from 63 to 13,400 tests g− 1 with an average of 1700 tests g− 1 (s = ± 2480). Faunal diversity ranged from 4 to 15 species with an average 10 species per sample (s = ± 2.3). Both faunal density and diversity decreased in areas (biotopes 1 and 3) dominated by clay and silt (grain size < 63 μ m) rich in organic matter. Degradation of organic matter by aerobic and anaerobic bacteria could lead to very low dissolved oxygen in pore and bottom waters where foraminifera live. Faunal data were used to divide the lake into three ecological biotopes. Samples from biotopes 1 and 3 are characterized by high clay-and-silt content, with Ammonia tepida and Quinqueloculina seminula characterizing biotope 1 and A. tepida, Q. seminula and Cribroelphidium excavatum dominating biotope 3. Samples from biotope 2 are characterized by bioclastic sand-dominated substrates that are rich in Q. seminula, A. tepida, Quinqueloculina poeyana, Bolivina striatula and Rosalina globularis.Ammonia tepida and Quinqueloculina seminula compose ~70% of the total foraminiferal assemblage in Lake Qarun. The distribution patterns of these species indicate that each is controlled by distinct environmental factors. In biotopes 1 and 3, A. tepida positively correlates with high clay-and-silt content and Q. seminula correlates with high total dissolved solids. Cribroelphidium excavatum correlates positively with magnetic susceptibility and negatively with total dissolved solids (TDS). In biotope 2, Quinqueloculina poeyana, Bolivina striatula and Rosalina globularis correlate positively with coarse bioclastic substrates enriched in phytal remains, a condition consistent with the presence of the epiphytic taxon R. globularis. The occurrence of these halophilic species in Lake Qarun seems to be a consequence of rising "salinity" that has made the lake a suitable habitat for these foraminiferal taxa. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.