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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.

2

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.

3

Microfouling development on artificial substrates deployed in the central Red Sea

Balqadi A. A., Salama A. J., Satheesh S.

Oceanologia

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2018

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No. 60 (2)

219--231

EN

Microfouling is the initial step in the growth of biofouling on hard substrata submerged in marine waters. In this study, microfouling development on nylon nets submerged in the central Red Sea coast of Saudi Arabia was analyzed during the winter and summer seasons for a period of 5 days each. The results showed a well-established biofilm community on nylon nets submerged for 24 h, with bacteria and diatoms being the primary colonizers. Protein was the major organic component of the biofilm that developed on the nylon nets during the winter and summer seasons. Navicula spp., Nitzschia spp., Cylindrotheca spp., and Pluerosigma spp. were the dominant diatom species settled on the nylon nets. Pseudoalteromonas shioyasakiensis, Planomicrobium sp., Vibrio harveyi and Pseudoalteromonas rubra were the dominant bacteria isolated from the nylon nets. While the abundance of bacteria showed a positive correlation with the nutrient concentration of the biofilm during both winter and summer seasons, diatom density exhibited a significant positive relationship with the biofilm nutrients during the winter season only. The results also revealed significant seasonal variations in the abundance of microfouling organisms and accumulation of nutrients on nylon nets.

4

Diatom assemblages as indicators of salinity gradients : a case study from a coastal lake

Rzodkiewicz M., Gąbka M., Szpikowska G., Woszczyk M.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 3

325--339

EN

In order to understand the variability of diatoms in coastal lakes and its relationship to salinity, the authors have conducted a two-year study at Lake Resko Przymorskie (the Southern Baltic coast), which has a salinity between 1.9-4.8 PSU. Redundancy analysis (RDA) was used to describe the relationship between the species composition and selected variables. Four of the 10 measured variables of surface water chemistry (Cl- and PO43- concentrations, temperature, and pH) significantly explained 23% of the variation in the diatom species composition. We found 82 taxa of diatoms (mostly tychoplanktonic) and determined the optimum and tolerance levels of salinity for predominant taxa (49 species with minimum 2% abundance). The optimum chloride concentration for the predominant diatoms ranged from 1471 to 2961 mg Cl- l-1. The most abundant brackish water species was Pseudostaurosiropsis geocollegarum. Brackish-freshwater diatoms were represented by Cyclotella atomus, Cyclotella meneghiniana, Diatoma tenuis and Staurosira subsalina. The most abundant fresh-brackish water diatoms were Amphora pediculus, Fragilaria sopotensis, Hippodonta hungarica, Pseudostaurosira brevistriata and Staurosira construens. Freshwater taxa accounted for as little as 1% of the population. This study provides new data on the ecology of coastal lakes and the possibility of using diatom-based transfer functions in the reconstruction of past environmental changes.

5

Additional information on the distribution and ecology of the recently described diatom species Geissleria gereckei

Vidakovic D., Cantonati M., Mogna M., Jakovljević O., Šovran S., Lazović V., Stojanović K., Đorđević J., Krizmanić J.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 1

18--23

EN

The main objective of this paper is to report new information about the distribution and ecology of a recently described diatom species, Geissleria gereckei. The opportunity for updating the information on the distribution and ecology of the species was provided by the finding of well-developed G. gereckei populations on the lithic material and bryophytes in the Raška and Mlava rivers (Serbia). For several years after the first description, G. gereckei has been known only from the type locality and from another spring in the Dolomiti Bellunesi National Park (the south-eastern Alps). After accurate LM and SEM observations, we provide evidence for the occurrence of the species also in the two above-mentioned rivers in Serbia, as well as in the south-western and south-eastern Alps. After an extensive literature search, it appears that the species is known with certainty only from these sites. Our observations and details from the literature suggest that the species is able to occupy a much broader ecological niche than the very-specific one observed at the time of discovery. The two main determinants for the species’ occurrence appear to be the carbonate nature of the catchments or aquifers, and the ability of the species to be competitive in habitats or microhabitats exposed to seasonal desiccation.

6

Rare and new records of diatoms in Turkey from Kütahya flowing waters

Solak C. N., Kulikovskiy M. S., Kaleli A., Gönülol A.

Oceanological and Hydrobiological Studies

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2016

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Vol. 45, No. 4

564--587

EN

Diatoms are one of the key organisms used in biomonitoring studies and they occur in a wide variety of environments, exhibiting a broad range of tolerance to abiotic factors. Historically, the first freshwater diatom study in Turkey was conducted in 1844 by Ehrenberg based on the material collected from the Murat and Aras Rivers. Situated between large continents (Eurasia and Africa), Turkey comprises areas of very diverse geological, climatic and environmental conditions, so we should expect that organisms such as diatoms show high diversity in this region. The aim of this study is to present new sites of rare and new records in Turkey from different genera along with morphological and ecological characteristics. As a result, a total of 73 species (24 rare and 49 new records) are presented in this study.

7

A multidisciplinary study on the palaeoenvironmental history of the Resko Przymorskie Lake spit during the Late Glacial and Holocene (the southern Baltic coast, NW Poland)

Sydor P., Krzymińska J., Rzodkiewicz M., Kotrys B.

Geological Quarterly

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2015

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Vol. 59, No. 3

531--550

EN

The paper presents the results of sedimentological and biostratigraphical analyses from the Resko Przymorskie Lake spit (NW Poland), supported by radiocarbon datings. The study has aimed to recognize the geological structure of the spit and its base and to recognize the palaeoenivronmental changes. Nine sedimentary series composing the Resko Przymorskie Lake spit have been distinguished (I–IX). The oldest sediments are the Vistulian Glaciation till (series I) and fluvioglacial sand and gravel (series II). In the Early Holocene, in the study area there was a river valley (series III) followed by a shallow water basin (series IV), which was replaced by a peat bog (series V). In the Atlantic (7.4 ka cal BP), the water level rose (Littorina transgression) and accumulation of lagoonal sediments started (series VI). Biostratigraphic analysis of deposits in series VI indicates a marine influence. In the Atlantic and Subboreal, the spit moved southwards and fine sand (series VII) was deposited on lagoonal gyttja and silt (series VI). In the western part of the study area, peat accumulated (series VIII), dated at 6.7 ka cal BP (Late Atlantic). The youngest series IX is composed of aeolian fine sand in white dunes that formed in the last 400 years.

8

Use of siliceous algae as biological monitors of heavy metal pollution in three lakes in a mining city, southeast China

Chen X., Mao X., Cao Y., Yang X.

Oceanological and Hydrobiological Studies

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2013

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Vol. 42, No. 3

233--242

EN

In order to assess the ecological status of three lakes in a historical mining city (SE China), water metal concentrations and surface sedimentary diatoms and chrysophyte cysts were analyzed in 20 sampling sites. The significant correlations between the algal indices and the cumulative criterion unit (CCU) scores confirmed the importance of heavy metals in shaping algae communities. In the metal-polluted sites, diatom assemblages were dominated by metal-tolerant species, such as Nitzschia palea and Nitzschia perminuta. In the unpolluted samples, diatom assemblages were characterized by Cyclostephanos dubius, Discostella pseudostelligera and Aulacoseira species (mainly A. alpigena, A. granulata and A. ambigua). These dominant taxa in the unpolluted samples might be sensitive to metal contamination but tolerant of eutrophication. In addition, nonspherical cysts were much more abundant in the polluted sites, indicating that their presence should be indicative of metal contamination in this region. This study provides some clues for future metal pollution assessment through the use of siliceous algae in metal polluted lakes.

9

Occurrence of a multi-species diatom bloom dominated by Proboscia alata (Brightwell) Sandstorm along the southwest coast of India

Cicily L. T., Padmakumar K. B., Asha Devi C. R., Sanjeevan V. N.

Oceanological and Hydrobiological Studies

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2013

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Vol. 42, No. 1

40-45

EN

The present communication reports on the occurrence of a multi-species diatom bloom in the upwelled waters along the southwest coast of India. During the late summer monsoon season (September 2009) a multi-species diatom bloom with a pale green discoloration of the sea surface was observed in the coastal waters of southwest coast of India. The bloom spread over an area of approximately 15 km2 along the coastal waters off Kannur (Lat. 11°59.471 N, Long. 75°03.446 E). Total diatom cell density of the bloom area was 16 × 104 cells l-1. Proboscia (=Rhizosolenia) alata (Brightwell) Sandstrom constituted 90% of the total phytoplankton population. Other phytoplankton groups that contributed to the bloom population included Chaetoceros spp., Pseudo-nitzschia spp., Rhizosolenia spp., Coscinodiscus sp., Leptocylindrus danicus, Thalassiosira sp., and Bacteriosira sp. Among these Pseudo-nitzschia multiseries, a toxic species with the ability to produce potent neurotoxin domoic acid, was observed with a cell density of 4 × 103 cells l-1. Surface chlorophyll a concentration of the bloom region was 14.1 μg l-1. Nutrient concentrations of the bloom area were 0.01 μmol l-1 for NO2-N, 0.1 ěmol l-1 for NO3- N, 0.83 μmol l-1 for PO4-P and 11.44 μmol l-1 for SiO4.

10

Pilot study of the influence of thermoplastic starch based polymer packaging material on the growth of diatom population in sea water environment

Guzman A.M., Janik H. Z., Mastalerz M., Kosakowska A.M.

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 2

57-61

EN

Novel polymeric packaging materials susceptible to environmentally friendly decomposition appeared on the global market. The paper is devoted to an investigation of the impact of degradable polymer packaging on marine life. The chosen polymer was a commercial packaging based on thermoplastic starch (TPS over 85%). The microorganism chosen was Phaeodactylum tricornutum diatom (identified in many aquatic reservoirs, with a tendency to flow with seawater plankton in places of great saline oscillation). The packaging material was incubated both in natural seawater and in the presence of diatom population. The chlorophyll a content was determined as the criterion of diatom growth in the presence of tested polymers. The polymer surface and the colour changes in the diatom culture were recorded photographically. The presence of polymeric samples significantly changed the kinetic of diatom growth in seawater during incubation affecting its biological balance. During the experiment in seawater, diatom adhered to polymer surfaces and the polymer stimulated their growth.

11

Two climatic oscillations during the eemian interglacial : preliminary results of multi-proxy researches of palaeolake at solniki, Ne Poland

Kupryjanowicz M., Ciszek D., Morosław-Grabowska J., Marciniak B., Niska M.

Polish Geological Institute Special Papers

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2005

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Vol. 16

53--57

EN

Lake series from the Eemian Interglacial and Early Vistulian has been discovered at Solniki in the Białystok Upland region, north-eastern Poland. Preliminary results of interdisciplinary researches (pollen, diatom, Cladocera, isotopic and magnetic susceptibility analyses) were used to illustrate the changes of the Eemian climate. At present stage of investigations, there are found signs of two abrupt climatic oscillations - first with very humid climate took place at middle part of the regional Carpinus pollen zone (E5 R PAZ), and second with cold and dry climate at middle part of the regional Pinus zone (E7 R PAZ).

PL

W Solnikach na Wysoczyźnie Białostockiej (północno-wschodnia Polska) odkryto serię osadów jeziornych reprezentujących interglacjał eemski i wczesny vistulian. Wstępne wyniki badań interdyscyplinarnych (analiza pyłkowa, okrzemkowa i Cladocera, pomiary podatności magnetycznej osadów oraz zawartości izotopów stabilnych tlenu i węgla) wykorzystano do zilustrowania zmian klimatu podczas interglacjału eemskiego. Udokumentowano dwie gwałtowne oscylacje klimatu - pierwsza z ciepłym i bardzo wilgotnym klimatem (?opady) miała miejsce w środkowej części poziomu pyłkowego E5 Carpinus, druga z klimatem suchym i bardzo zimnym - w środkowej części poziomu E7 Pinus.

12

Założenia budowy algorytmu do automatycznego rozpoznawania okrzemek w obrazach monochromatycznych

Sekulska-Nalewajko J., Grabowski S.

Automatyka / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2004

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T. 8, z. 3

73-79

PL

Artykuł przedstawia zagadnienia dotyczące przetwarzania obrazów komórek okrzemek do celów ich automatycznego rozpoznawania. We współczesnych problemach ekologii i ochrony środowiska okrzemki, mikroskopijne glony, są postrzegane jako jedne z najlepszych organizmów wskaźnikowych w systemach wodnych. W pracy podano założenia metodologiczne i koncepcyjne budowy systemu służącego do ich klasyfikacji taksonomicznej. Na analizę komórek okrzemek, które charakteryzują się znacznym zróżnicowaniem morfologicznym i złożoną teksturą, składa się kilka etapów. Są to: wydzielenie obiektu z tła oraz analiza obiektu, która obejmuje detekcję konturu, wyznaczenie osi symetrii i wyselekcjonowanie elementów ornamentacji komórki. Pierwszy etap, omówiony w tym artykule, opiera się na stosowaniu algorytmów segmentacji obrazu w celu wyodrębnienia obiektu z tła do dalszej analizy. W pracy przeprowadzono eksperyment z kilkoma algorytmami binaryzacji obrazu, w tym z własną modyfikacją algorytmu Bernsena, która usuwa część artefaktów wprowadzanych przez metodę oryginalną.

EN

The article presents the problems of processing images of diatom cells, goaled to automatic taxonomic classification. In the contemporary ecology and environment protection diatoms, being microscopic algae, are considered to be one of the best indicators in water systems. In this work we list the methological assumptions and main concepts for a system for automatic taxonomic classification of diatoms. Diatom cells have diverse shapes and textures, which makes the analysis of their images a difficult and complex task. The analysis requires several stages, that is: extracting the object from the background, contour detection, determination of the symmetry axis and extracting the features of shell pattern. The first stage discussed in this article is image binarization, feasible for further analysis. We experiment with a new algorithm, including own modification of Bernsen's method, which mitigates the artifacts specific to the original variant.

13

Mikroskopia w monitoringu stanu czystości wód

Janik H, Pocheć K

LAB Laboratoria, Aparatura, Badania

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2001

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R. 6, nr 2

15--17