Testing foraminiferal environmental quality indices along a well-defined organic matter gradient in the Eastern Mediterranean

Coastal environments are affected by multiple pressures resulting from anthropogenic activities, among which organic enrichment (Corg) is particularly important. Foraminiferal communities react to changes in community structure (density, diversity, species composition) and behaviour (metabolism, feeding strategy, reproduction, mortality, etc.). A number of biotic indices based on foraminiferal faunas have been developed measure the impact ecological quality marine soft bottom environments. However, origins matter its diffuse dispersion make it difficult clearly identify gradients along them. In this context, disposals activated sewage sludge, represent localised point sources matter, offer possibility study faunal successions a well-developed stress gradient. The main objectives test 1) assignments Mediterranean foraminifera as recently proposed Jorissen et al. (2018), 2) two indices, groups indicator species, Sea, TSI-Med Foram-AMBI, such an gradient, outlet off Israeli coast, south Tel-Aviv. Along studied Caronia silvestrii dominated most severely impacted zone. Further away outlet, were characterised dominance Ammonia tepida. Finally, least area, farthest Leptohalysis scottii was dominant taxon. Our observations strongly contrast with earlier C. L. III (3rd order opportunists) V (1st opportunists), respectively (Jorissen al., 2018). This discrepancy suggests that additional studies urgently needed better characterise strategies major index species. When, we propose here, not included group stress-tolerant taxa for TSI-Med, reassigned both tested show decreasing greater distance outlet. These reassignments underline need distinguish between opportunistic taxa, do give same information about environmental quality.