Genetic structure of Pelagia noctiluca was studied in the Mediterranean and eastern Atlantic based on COI and ITS genetic markers. Phylogeographic analysis revealed two clades, larger consisting of specimens from all sampling sites, and the smaller, mostly Mediterranean. Haplotype diversity was high throughout the sampled area, no strongly supported genetically or geographically distinct groups were found. Long distance dispersal and lack of isolation by distance point to admixture among Mediterranean and Atlantic populations. These results are crucial for uncovering recent Pelagia blooms.
COBISS.SI-ID: 2249295
We present a method for in-situ monitoring of phytoplankton composition changes in a marine environment. The method is based on delayed fluorescence excitation spectra analyzed with CHEMTAX software, which is generally used for determination of phytoplankton communities with HPLC pigment data. Delayed fluorescence (DF) is a photosynthetic parameter that can only be measured in living cells. Algal DF excitation spectra are group-specific, based on their composition of photosynthetic pigments.
COBISS.SI-ID: 2299983
Results of surface water partial pressure of CO2 in the Gulf of Trieste, the northernmost part of the Mediterranean, are presented. Sea surface pCO2 was measured using the Submersible Autonomous Moored Instrument during four deployments from 2007 to 2008. The CO2 measurements were combined with physical observations, satellite chlorophyll a data and daily river discharge. Sea surface pCO2 ranged from 200 to 500 µatm and mean CO2 fluxes from the atmosphere into the ocean from -5.0 to -12.1 mmol m-2 d-1 resulting in a net sink of atmospheric CO2 of -2-3 mol m-2 yr-1.
COBISS.SI-ID: 2239823
Decomposition of jellyfish after bloom results in release of nutrients and change in oxygen dynamics. Response of ambient bacterial community to jellyfish biomass was evaluated in the Gulf of Trieste and Mljet marine lake using in situ experiments. Addition of jellyfish triggered changes in bacterial community with increase of bacterial production and abundance coupled with ammonium accumulation. Results of bacterial community structure diverged between two systems presumably because Aurelia is not permanently present in the Gulf of Trieste while in Mljet lake occurs throughout the year.
COBISS.SI-ID: 2202703
In this paper the results of a data base of more than 30 years of field observations on chlorophyll a concentrations combined with the last decade satellite data, are presented. Results demonstrate a global tendency towards chlorophyll a reduction, more marked in the eutrophic area under the influence of the Po River, but detectable also in the Gulf of Trieste. Results are consistent with recently evidenced decrease in concentrations in nutrient concentrations in the Northern Adriatic. results indicate the need to understand the underlying changes in the phytoplankton community.
COBISS.SI-ID: 2015055