Distribution of benthic macroinvertebrates in relation to physico-chemical properties in the Köyceğiz-Dalyan estuarine channel system (Mediterranean Sea, Turkey)

Abstract

The Köyceğiz-Dalyan Channel system is located between the ectogenic, crenogenic and meromictic Lake Köyceğiz and the Mediterranean Sea. Twenty one species belonging to Bryozoa, Gastropoda, Bivalvia, Polychaeta and Crustacea were found at 6 sampling sites from the channel entrance of Lake Köyceğiz to the Mediterranean Sea. The faunal assemblage of sampling sites 3 and 4 along the Dalyan Channel had the highest species diversity because of the almost similar effects of Lake Köyceğiz and the Mediterranean Sea on the benthic assemblages and stable salinity compared to the other stations. The distribution of species in the channel system is mainly affected by salinity, temperature, phosphate, Mg²⁺, DO (dissolved oxygen) and SO₄^2-. Regular physical, chemical and biological monitoring of the channel system is recommended.