Новий словник епітетів української мови

У статті йдеться про засади створення «Нового словника епітетів української мови» (автори С. П. Бибик, С. Я. Єрмоленко, В. І. Єрмоленко). Словник значно доповнено за рахунок нових заголовкових слів та збільшення кількості узгоджених означень до всіх заголовкових слів. Розширено сполучуваність заголовкових іменників із прикметниковими словам. Нова структура словникової статті виокремлює епітети, що вживаються в структурі порівняння, а також епітети у структурі метафори

Water residence time : A regulatory factor of the DOM to POM transfer efficiency

The pools of dissolved (DOM) and particulate organic matter (POM) and of transparent exopolymeric particles (TEP) were studied along two sampling gradients in the lagoon of New Caledonia in relation to the residence time of the water masses. The efficiency of the transfer of material from the dissolved to the particulate phase via TEP formation, indicating the physicochemical reactivity of organic matter, was investigated. DOM, POM, and TEP concentration increased along the sampling gradients, but their relative proportions varied. The contribution of the TEP pool to POM increased from 20% to 60%, from the most oligotrophic stations to the more anthropogenically affected bays. According to the low density of TEP and to the observed variations of the proportion of TEP compared with more conventional and solid particles, the aggregates formed inside the bays would be either neutrally or positively buoyant, whereas in the vicinity of the coral barrier, they would be negatively buoyant. As a result, the downward export of organic matter inside the bays might be greatly reduced, thereby prolonging the residence time of organic matter in the water column. The efficiency of the DOM/TEP transformation and the TEP turnover rate dropped drastically when the residence time increased from 0 to 50 d, suggesting that the reactivity of organic matter is reduced as it ages. The very high residence time of the water mass inside the bays, constrained by the hydrodynamic circulation inside the lagoon, favors the installation of a feedback system in which organic matter is not exported and is continuously degraded, leading to the formation of refractory DOM with a low physicochemical reactivity. In contrast, organic matter produced in areas in which water mass has a low residence time (i.e., near the coral barrier) is rapidly exported because of its high physicochernical reactivity

Production of individual marine organic aggregates using paramagnetic microspheres : a new tool for examining microbial associations with aggregates

We describe a new method to produce marine aggregates from natural organic material based on the sticking properties of transparent exopolymeric particles. Seawater samples were prescreened and ultrafiltered to concentrate the 30 kDa to 10 mu m size fraction. First, we produced small magnetizable aggregates by combining glass microfibers and paramagnetic 1-mu m beads with the organic matter present in the concentrated solution. The second step involved clustering the small aggregates into a single macro-aggregate, using a small ring-shaped magnet as an aggregation nucleus. Viral and bacterial densities, determined after dissolution of the newly formed aggregates with methanol, averaged 13.8 x 10(6) +/- 3.6 x 10(6) vir. agg.(-1) and 4.1 x 10(6) +/- 1.1 x10(6) bact. agg.(-1). Bacterial respiration and production measurements of single aggregates averaged 8.47 +/- 1.72 nmol O-2 agg.(-1) h(-1) and 1.54 +/- 0.45 ng C agg.(-1) h(-1), respectively. Particulate organic carbon and nitrogen content of the newly formed macro-aggregates averaged 31.92 +/- 2.67 mu g C agg.(-1) and 3.44 +/- 0.43 mu g N agg.(-1), respectively. This approach allows the concentration and isolation of the organic matter precursors that compose natural aggregates and provides a simple protocol for recombining those precursors into single newly formed macro-aggregates, which can then be easily manipulated for further investigation. This method is a new tool for investigations into the interactions between microorganisms and marine aggregates and their implications at the ecosystem level, but also into the interactions between aggregates and dissolved organic or inorganic substances

Do the levels of industrial pollutants influence the distribution and abundance of dinoflagellate cysts in the recently-deposited sediment of a Mediterranean coastal ecosystem?

We studied the relationships between sediment industrial pollutants concentrations, sediment characteristics and the dinoflagellate cyst abundance within a coastal lagoon by investigating a total of 55 sampling stations within the Bizerte lagoon, a highly anthropized Mediterranean ecosystem. The sediment of Bizerte lagoon is char- acterized by a high dinocyst abundance, reaching a maximum value of 2742 cysts·g−1 of dry sediment. The investigated cyst diversity was characterized by the presence of 22 dominant dinocyst morphotypes belonging to 11 genera. Two dinoflagellate species dominated the assemblage: Alexandrium pseudogonyaulax and Protoperidinium claudicans, representing 29 to 89% and 5 to 38% of the total cyst abundance, respectively, depending on the station. Seven morphotypes belonging to potentially toxic species were detected, including Alexandrium minutum, A. pseudogonyaulax, Alexandrium catenella/tamarense species complex, Lingulodinium polyedrum, Gonyaulax cf. spinifera complex, Prorocentrum micans and Protoceratium reticulatum. Pearson correlation values showed a positive correlation (α = 0.05) between cyst abundance and both water content and fine silt sediment content. Clustering revealed that the highest abundance of cysts corresponds to stations presenting the higher amounts of heavy metals. The simultaneous autoregressive model (SAM) highlighted a significant correlation (α = 0.05) between cyst accumulation and two main factors: sediment water content and sediment content for several heavy metals, including Hg, Cd, Cu, Ni and Cr. These results suggest that the degree of heavy metal pollution could influence cyst accumulation patterns.peer-reviewe

Cyanobacteria track water in desert soils

International audienc

Impact of zinc and nickel on oxygen consumption of benthic microbial communities assessed with microsensors

In this study, the effect of zinc and nickel on oxygen consumption in sediments was determined using oxygen microsensors. Sediments from the southwest lagoon of New Caledonia, in the vicinity of the city of Noumea, were incubated nearby in situ conditions and exposed to Zn and Ni concentrations of 20 and 60 mg l(-1). The depth distribution of oxygen consumption was estimated from the steady-state oxygen microprofiles, and the effects of metal were compared on the distributions before and after spiking. In most cases, metal had a strong effect on oxygen consumption at the surface. After 6 h exposure, oxygen consumption was only 10-40% of the initial value. However, the strong decrease in oxygen consumption observed at the sediment surface was counterbalanced by an increase of oxygen consumption deeper in the sediment. This is probably due to (i) a downward migration of aerobic microbial microorganisms living at the surface in order to escape the toxic effect of metal or/and (ii) a switch of the facultative aerobes from the low efficiency fermentation mode to the high-energy aerobic respiration mode. (c) 2005 Elsevier B.V All rights reserved

Monitoring of oxygenic and anoxygenic photosynthesis in a unicyanobacterial biofilm, grown in benthic gradient chamber

International audienc

A Benthic Gradient Chamber for culturing phototrophic sulfur bacteria on reconstituted sediments

International audienc