Benthic foraminiferal assemblages of the Erdek Bay (SW Marmara Sea)

• Published in: Yerbilimleri Vol. 27; no. 3; pp. 125 - 141
• Main Authors: Avsar, N, Aksu, A, Dincer, F
• Format: Journal Article
• Language: Turkish
• Published: 01.12.2006
• Subjects: Cassidulina carinata; Cribroelphidium; Discorbinella bertheloti; Elphidium crispum; Marine; MED, Marmara Sea
• ISSN: 1301-2894

The distribution and assemblages of recent benthic foraminifera in the Gulf of Erdek (SW Marmara Sea) were investigated on the basis of 15 surface sediment samples. These are generally characterized by the lithologies of gravel, sand and mud. A total of 74 species belonging to 24 families and 46 genera were determined from these samples. The agglutinated species can never reach a dominant number, however the calcareous forms have five benthic foraminiferal assemblages which are dominant in number. These are Ammonia compacta Hofker, Cassidulina carinata Silvestri, Discorbinella bertheloti (d'Orbigny), Cribroelphidium poeyanum (d'Orbigny), and Elphidium crispum (Linne), respectively. Finally, the main foraminiferal parameters were used in statistical assessments and the species richness (d'), Shannon-Wiener diversity (H') and evenness (J') were calculated. Although the fauna exibits moderate diversity and richness, it indicates a homogenous distribution based on the statistical data. In addition, Q-mode cluster analysis was carried out and distribution dendrogram with respect to stations was prepared. The Q-mode cluster for the study area data, at the arbitrary similarity level of 50%, produced only one cluster.Original Abstract: Bu calismada, Erdek Koerfezi (GB Marmara Denizi) deniz dibi guencel coekellerinde bulunan bentik foraminiferlerin topluluklari ve dagilimlari, boelgeden derlenen 15 adet coekel oerneginden incelenmistir. Bu oernekler genel olarak camur, kum ve cakil litolojileriyle temsil edilmektedir. Boelgede toplam 24 familyaya ait 46 cins ve 74 foraminifer tuerue tanimlanmistir. Tanimlanan foraminiferlerden aglutine kavkili olanlar egemen sayiya erisemezken, kalker kavkililardan 5 foraminifer toplulugu saptanmistir. Bunlar sirasiyla; Ammonia compacta Hofker, Cassidulina carinata Silvestri, Cribroelphidium poeyanum (d'Orbigny), Discorbinella bertheloti (d'Orbigny), Elphidium crispum (Linne)'dir. Son olarak istatistiksel analiz icin ana foraminifer parametreleri kullanilarak, tuer zenginligi (d'), Shannon-Wiener cesitliligi (H') ve homojenlik (J') degerleri hesaplanmistir. Elde edilen verilere goere; boelgede fauna orta derecede bir cesitlilik ve tuer zenginligi sergilemesine karsin, homojen bir dagilim goestermektedir. Ayrica "Q tipi kueme " analizi yapilmis ve istasyonlara goere dagilim dendrogrami cizilmistir. inceleme alani icin, Q-tipi kuemenin %50'lik keyfi benzerlik seviyesinde tek bir kueme olusturdugu belirlenmistir.