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A fossil diatom-based reconstruction of sea-level changes for the Late Pleistocene and Holocene period in the NW South China Sea

Zhang Jinpeng, Tomczak Michał, Witkowski Andrzej, Zhen Xia, Li Chao

Oceanologia

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2023

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Vol. 65 (1)

211-229

EN

Marine transgressions-regressions have profoundly shaped marginal seas following global sea-level fluctuations driven by climate change. This study on a sedimentary core profile SO219/31-4 from the Beibu Gulf, northwestern South China Sea (SCS), reveals information about paleoenvironment, paleoceanography and paleoclimate changes through fossil diatom assemblages and grain size distributions during the last ca. 12900 cal. yr. BP. Eight local diatom assemblage zones were distinguished and assigned to paleoenvironmental fluctuations recording sea-level and depositional environment changes in eight stages, ca. 12900–11700 (stage 1), ca. 11700–9500 (stage 2), ca. 9500–7200 (stage 3), ca. 7200–5800 (stage 4), ca. 5800–3800 (stage 5), ca. 3800–2400 (stage 6), ca. 2400–800 (stage 7) and ca. 800–0 (stage 8), cal. yr. BP. After the low sea level of stage 1 within the last deglaciation, rapid increases in sea level in stages 2 and 3 were recorded as meltwater events pulse-1B and pulse-1C resulting in marine transgression rates of ca. 16 m/kyr and 8 m/kyr, respectively. The high sea level, above the present level, in stages 4 and 5, in the Middle Holocene Climatic Optimum period, was clearly documented by more significant open sea/tropical diatom species and coastal planktonic species percentages, respectively. The late Holocene regression of sea levels was marked by a pronounced reversion of diatom taphocoenosis, responding to neoglacial climate. Fossil diatom assemblages outlined responded to paleoclimate of global warming in the deglacial and early Holocene. This study provides additional insights into the late Pleistocene and Post-glacial history of a tropical-subtropical shallow water gulf, in the NW-SCS.

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Upsilococconeis dapalistriata gen. nov. & comb. nov. (Bacillariophyta) : a pantropical marine member of Cocconeidaceae

Riaux-Gobin Catherine, Witkowski Andrzej, Risjani Yenny, Yunianta Yunianta, Berteaux-Lecellier Véronique, Kryk Adrian, Peszek Łukasz, Daniszewska-Kowalczyk Genowefa

Oceanological and Hydrobiological Studies

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2022

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Vol. 51, No. 1

23--31

EN

Cocconeis dapalistriata, first described as a member of the genus Cocconeis, is re-examined due to its unique ultrastructure. Both valvocopulae of this taxon show significant differences compared to those found in the genus Cocconeis. They are expanded and show some similarities with those found in Amphicocconeis. On the other hand, terminal parts of the raphe valve (RV) in C. dapalistriata are simple and the raphe valve (RV) striae are composed of small round areolae with a hymenate occlusion with radial slits, similar to those observed in Cocconeis. Campyloneis and Xenococconeis also have expanded valvocopulae but with numerous morphological differences compared to those found in C. dapalistriata. Furthermore, the areolae of the sternum valve (SV) in C. dapalistriata are occluded by a concave velum with no apparent internal slits, and externally ornamented with irregular silica crystals. Upsilococconeis Riaux-Gobin, Witkowski & Risjani gen. nov. is proposed to accommodate the latter taxon. First described from the Western Indian Ocean (Mascarenes), it was subsequently listed from the Western Pacific Ocean (Guam), the South Pacific Ocean (French Polynesia and New Caledonia) and from the Eastern Indian Ocean (Indonesia), and thus may qualify as pantropical.

3

Paradoksy w unormowaniach prawnych dotyczących zawartości wielopierścieniowych węglowodorów aromatycznych (WWA) w wodach

Witkowski Andrzej, Ślósarczyk Kinga

Przegląd Geologiczny

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2020

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Vol. 68, nr 4

256--262

EN

The paper provides an analysis of current Polish regulations on polycyclic aromatic hydrocarbons (PAH) in water. The issue was also described in relation to international law. Inconsistency in regulations in terms of definitions of the sum of PAH is highlighted. The influence of PAH concentrations on the classification of water chemical status and the assessment of drinking water quality was analyzed based on the results of concentrations of six PAHs: benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(ah)anthracene, benzo(ghi)perylene and indeno(1,2,3-cd)pyrene. The PAH concentrations were determined in 36 water samples, including 28 samples of spring water and eight samples of snowmelt. The results obtained for most of the samples revealed elevated concentrations of benzo(a)pyrene. The authors underline the fact that a separate assessment of benzo(a)pyrene, the sum of six PAHs, and the sum of four PAHs unveil inconsistency in water quality evaluation. The results also suggest that only benzo(a)pyrene should be considered in the classifications mentioned, since its determination gives the actual view on the water quality in terms of PAH concentrations. The assessments for the sum of six PAHs and four PAHs in accordance with existing regulations indicate higher quality classes, meaning a better water quality in comparison with the concentration of benzo(a)pyrene itself.

4

Navicula dermochelycola sp. nov., presumably an exclusively epizoic diatom on sea turtles Dermochelys coriacea and Lepidochelys olivacea from French Guiana

Riaux-Gobin Catherine, Witkowski Andrzej, Kociolek John Patrick, Chevallier Damien

Oceanological and Hydrobiological Studies

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2020

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Vol. 49, No. 2

132--139

EN

Epizoic diatom communities were studied on four turtle species (Chelonia mydas L., Eretmochelys imbricata L., Lepidochelys olivacea Eschscholtz and Dermochelys coriacea Vandelli) from the Eastern Caribbean, the Equatorial West Atlantic and the South Pacific. In the present study, we focused on one taxon of Navicula Bory de Saint-Vincent, described here as a new taxon, which was found on seven individuals of Dermochelys coriacea and one individual of Lepidochelys olivacea in French Guiana. The new Navicula taxon was found neither on Chelonia mydas (83 specimens examined) nor Eretmochelys imbricata (13 specimens examined). Furthermore, the new taxon appears to have a restricted biogeography, as so far it has only been reported from French Guiana. A species of Navicula is reported for the first time as a supposedly exclusive epizoic taxon. Navicula dermochelycola sp. nov. is characterized in detail; its ultrastructure is described and compared with other members of Navicula.

5

Propozycja wariantowych rozwiązań systemu kanalizacyjnego w gminie wiejskiej o rozproszonej zabudowie

Witkowski Andrzej, Heidrich Zbigniew

Gaz, Woda i Technika Sanitarna

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2020

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Nr 12

19--23

PL

W artykule przedstawiono różne warianty rozwiązania systemu kanalizacyjnego na przykładzie jednej z krajowych gmin wiejskich, charakteryzującej się rozproszoną zabudową. Dokonano analizy techniczno-ekonomicznej proponowanych wariantów, z uwzględnieniem kosztów budowy i eksploatacji, ze szczególnym uwzględnieniem kosztów zużycia energii elektrycznej i transportu ścieków. Wskazano jak dokonać wyboru najkorzystniejszego rozwiązania.

EN

The article presents various variants of the sewage system solution for the examplary national rural commune, characterized by scattered buildings. A technical and economic analysis of the proposed variants was performed, taking into account construction and operating costs, with particular emphasis on the costs of energy consumption and sewage transport. The way of choosing the most advantageous solution was presented.

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Epiphytic diatom assemblages on invasive Caulerpa taxifolia and autochthonous Halimeda tuna and Padina sp. seaweeds in the Adriatic Sea : summer/autumn aspect

Car Ana, Witkowski Andrzej, Dobosz Sławomir, Jasprica Nenad, Ljubimir Stijepo, Zgłobicka Izabela

Oceanological and Hydrobiological Studies

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2019

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Vol. 48, No. 3

209--226

EN

This study focuses on the taxonomy of epiphytic diatoms in the area of invasive macroalgae from the genus Caulerpa. Caulerpa species are characterized by the presence of secondary metabolites, such as caulerpenyne (CYN), the main function of which is a chemical defense mechanism against herbivores and epiphytes. Epiphytic diatoms were studied on fronds of Caulerpa taxifolia (“killer seaweed”) and, for comparison, on autochthonous macroalgae Padina sp. and Halimeda tuna at the eastern Adriatic Sea coast (Island of Hvar) in the summer and autumn of 2010. The qualitative analysis was performed with the use of light and scanning electron microscopy. The Shannon–Wiener Diversity Index determined for Caulerpa taxifolia showed a wide range of values (3.11–4.88), with a maximum in August and a minimum in October. While the number of taxa on Caulerpa taxifolia fronds increased from June (41) to August (88), it declined in autumn due to the high relative abundance of Cocconeis caulerpacola, which is a diatom typical for Caulerpa. On the other hand, the largest number of taxa on Padina sp. was observed in September (82). The detailed composition of epiphytic diatoms and seasonal dynamics in the area affected by the invasive macroalga Caulerpa taxifolia have been determined for the first time.

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Diatomaceous ooze in a sedimentary core from Mariana Trench: implications for paleoceanography

Zhang Jinpeng, Witkowski Andrzej, Tomczak Michał, Mccartney Kevin, He Gaowen, Zgłobicka Izabela

Acta Geologica Polonica

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2019

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Vol. 69, no. 4

627--643

EN

Diatomaceous ooze sampled from near the Mariana Trench sediment surface by gravity corer (Core JL7KGC05) revealed a high sedimentary abundance of Ethmodiscus rex (Rattray, 1890) Wiseman and Hendey, 1953 fragments and tropical open ocean planktonic diatom taxa including Azpeitia nodulifera (Schmidt, 1878) Fryxell and Watkins in Fryxell, Sims and Watkins, 1986 and Alveus marinus (Grunow, 1880) Kaczmarska and Fryxell, 1996. Subsurficial sediments from the ooze are assigned a Marine Isotope Stage 2 age, approximately at the Last Glacial Maximum. The occurrence of Ethmodiscus ooze suggests massive late Pleistocene blooms in the Northwestern Pacific Ocean and provides a plausible link to paleoceanographic and paleoclimatic changes related to Antarctic Intermediate Water mass, which carried a high dissolved silica content as silicon leakage that reduced dissolution rate of diatom frustules. Northward flow of Antarctic Intermediate Water was probably related to surface current migration and southward shift of the Northwest Pacific Gyre to form oligotrophic conditions that triggered Ethmodiscus rex blooms under unusual nutrient recycling conditions within the ocean system. This bloom hypothesis may help explain differential silica dissolution during the last glacial stage.