Macrofauna Communities in the Eastern Mediterranean Deep Sea

Abstract

Abstract. During two expeditions with RV ‘Meteor’ in summer 1993 and winter 1997/98 the structural and functional diversity of the benthic system of the highly oligotrophic eastern Mediterranean deep sea was investigated. The macrofauna communities were dominated by polychaetes even at the deepest stations. The fauna at shallow stations was dominated by surface deposit feeders, whereas subsurface deposit feeders and predators generally increased with depth. A high percentage of suspension‐feeding Porifera was found in the Levantine Basin. Mean abundance and number of taxa of both expeditions were significantly correlated to depth and distance to the nearest coast as well as to the total organic carbon (TOC) content in sediments. Numbers of taxa and abundance decreased generally with depth, although lowest numbers were not found at the deepest stations but in the extremely oligotrophic Levantine and Ierapetra Basin. Biomass measured during the second cruise was extremely low in the Ierapetra Basin and comparable to other extreme oligotrophic seas. The significant correlations found for TOC contents and macrofauna with distance to coast during both expeditions apparently reflect the role of hydrographically governed transport of organic matter produced in coastal regions into greater and extreme depths of the Mediterranean Sea. Seasonal differences in macrofauna communities due to seasonal differences in food supply were not found. However, recent large‐scale hydrographic changes (Eastern Mediterranean Transient, EMT) might change the oligotrophy and, thus, the structure of the benthic communities in the Eastern Mediterranean deep sea.

Spatio-temporal distribution of soft-bottom epibenthic fauna on the Cilician shelf (Turkey), Mediterranean Sea

“…The organic content complements the sediment type to reinforce this differentiation. This was true in the eastern Mediterranean deep sea (Kroncke et al 2003). Depth seems to be the governing factor for differentiating the fauna within the stations of similar sediment type in the Aegean Sea (Simboura et al 1998).…”

Exploring the Relationship between Macrofaunal Biodiversity and Ecosystem Functioning in the Deep Sea

“…The environmental effects were strong in the c-eM basin, where most relationships were context-dependent. Indeed, environmental conditions, such as food depletion or current regime have been reported to be major factors influencing and structuring benthic populations in the Eastern Mediterranean (Tselepides et al, 2000;Króncke et al, 2003;Tecchio et al, 2011;Giovannelli et al, 2013). Furthermore, Zeppilli et al (2016) showed that the high sea floor heterogeneity along an open slope system may shape BEF relationships, even on a very small spatial scale.…”

Spatial and temporal variation of soft-bottom peracarid (Crustacea: Peracarida) infauna in the Canakkale Strait (Turkey)

“…Depth and substrate are the most important factors influencing the structure of the benthic fauna (MUTLU & ERGEV, 2008), and it is well known that meiofauna and macrofauna abundance decrease with increasing depth in the eastern Mediterranean (TSELEPIDES et al, 2000;KRÖNCKE et al, 2003). According to SCIPIONE et al (2005) the number of crustacean species, individuals and diversity (H') diminish towards depth, while evenness (J) increases.…”