Copepod Community Structure in Pre- and Post- Winter Conditions in the Southern Adriatic Sea (NE Mediterranean)

Abstract

Copepod communities were studied along an east-west transect in the oligotrophic Southern Adriatic Sea. This dynamic region is under the influence of various physical forces, including winter vertical convection, lateral exchanges between coastal and open sea waters, and ingression of water masses of different properties all of which occurred during the investigation periods. Depth-stratified samples were taken with a Nansen net (250 µm mesh size) in pre- and post-winter conditions in 2015/2016. In December, the coastal copepod community was limited over the western flank, while epipelagic waters of the open and eastern waters were characterized by high diversity, low abundances in the central area, and subsurface/upper mesopelagic copepod species. In April, higher abundances were recorded over the entire vertical profile with the surface coastal copepod community present through the entire transect. Higher abundances in the central area during the post-winter period are probably a consequence of late-winter/early spring blooms near the center of the Southern Adriatic. Mesopelagic fauna of both months was characterized by high abundances of Haloptilus longicornis, characteristic species of the eastern Mediterranean, whose larger presence was favored by the cyclonic phase of the North Ionian Gyre and a consequent strong Levantine Intermediate Water ingression.

A Study on Spatio-Temporal Variations in Physicochemical Parameters and Ciliate Community Structure of Three Freshwater Bodies from Delhi, India.

“…Correlations between physicochemical parameters and ciliate communities were estimated using Pearson correlation, Principal component analysis (PCA) and non-metric multidimensional scaling (NMDS). This was used to estimate relationships between different seasons and sites in terms of physicochemical and diversity indices (Clarke and Warwick 2001;Hure et al 2020;Li et al 2018). All statistical analyses were performed using IBM SPSS 22.0 statistics software.…”

Coastal Eukaryotic Plankton Diversity of the Southern Adriatic as Revealed by Metabarcoding

“…Diversity 2024, 16,293 13 of 20 on morphological identification [28,29]. Most of the copepod genera recorded by metabarcoding are known as common species of the Adriatic, living mainly in coastal and surface waters (Paracalanus, Clausocalanus, Calanus, Calocalanus, Acartia, Centropages, Oithona and Euterpina), but some were characterised as very rare copepods for the Adriatic (Pachos, Neocalanus) in previous studies [25][26][27]. In addition to free-living (pelagic or benthic) copepods, the Southern Adriatic dataset also enabled the identification of some marine invertebrate parasites/symbionts (Pseudanthessius) [78].…”

“…For the Southern Adriatic, previous plankton research in this area also included mainly zooplankton and phytoplankton studies on certain representative groups. Zooplankton studies focused on copepods [25][26][27][28][29], tintinnids [30][31][32] and gelatinous invertebrates [33][34][35][36][37], while phytoplankton studies mainly characterised diatoms [38][39][40]. Moreover, the studies were predominantly based on traditional methods of taxa identification.…”

Copepod Diel Vertical Distribution in the Open Southern Adriatic Sea (NE Mediterranean) under Two Different Environmental Conditions

“…Those investigations mostly included relatively shallow stations above the continental shelf near Dubrovnik [14,15], while for the waters of the open Adriatic, detailed DVM patterns are available for the deep-water copepods during the summer period [16]. Recently, copepod species composition and their vertical and horizontal distribution in the South Adriatic during the winter mixing period were investigated and described in detail [18][19][20]. Additionally, for the first time in the Adriatic Sea, the strength of the backscatter signal from an Acoustic Doppler Current Profiler (ADCP) in relation to zooplankton vertical movement was investigated, including an eleven-year data set [21].…”