Faunistic and ecological assessment of interstitial Harpacticoida (Crustacea, Copepoda) on a sandy beach in Balikesir (Turkey)

Interstitial harpacticoids along the mediolittoral zones of Sarimsakli Beach, Turkey, were sampled monthly between April 2016 and March 2017 in order to reveal the effects of pH, water temperature, salinity, electrical conductivity, dissolved oxygen, and grain size on the occurrence and composition of the harpacticoids. Examination of the samples from nine stations revealed a total of 66 species. In terms of harpacticoid species abundance, Ectinosoma soyeri Apostolov, 1975 was ranked first followed by Sarsamphiascus angustipes (Gurney, 1927) and Leptomesochra eulitoralis Noodt, 1952. The variations in harpacticoid community were estimated by using some ecological indices (Species richness, Shannon's diversity and Pielou's evenness). Principal component analysis (PCA) based on the abiotic factors was applied for ordination of the stations. Relationships between environmental and temporal parameters as well as harpacticoid community structure were analyzed using distance-based Linear Models (DistLM). Relationships between environmental variables and most abundant species were determined with the Redundancy analysis (RDA). The abundance of S. angustipes and Klieonychocamptus ponticus (Serban and Plesa, 1957) were positively correlated with all tested variables except water temperature. The abundance of Klieonychocamptus kliei (Monard, 1935) was positively correlated with water temperature, grain size and salinity, while it was negatively correlated with dissolved oxygen and pH. The abundance of Ameira sp. andMicrosetella norvegica (Boeck, 1865) were negatively correlated with all tested variables except water temperature. The abundance of E. soyeri and Ameira parvula (Claus, 1866) were negatively correlated with all tested variables except pH. The abundance of Leptomesochra eulitoralis was positively correlated with water temperature and salinity, while it was negatively correlated with grain size, dissolved oxygen and pH.