scholarly journals Planktonic foraminifera in the seafloor of Wulan Estuary of Demak, Central of Java, Indonesia

2021 ◽  
Vol 919 (1) ◽  
pp. 012002
Author(s):  
R Hartati ◽  
M Zainuri ◽  
H Endrawati ◽  
W Widianingsih ◽  
B A Manuhuwa ◽  
...  
Keyword(s):  
Planktonic Foraminifera ◽  
Photic Zone ◽  
Sediment Samples ◽  
Composition And Structure ◽  
Surface Ornamentation

Abstract Planktonic foraminifera are marine heterotrophic protists that surround their unicellular body with elaborate calcite shells. They exhibit a range of trophic behaviors from indiscriminate omnivory to selective carnivory. The species inhabit the photic zone with various density. The present work was aimed to identify and determine the density of planktonic foraminifera in the seafloor of Wulan Estuary of Demak regency, Central of Java, Indonesia. The sediment in the seafloor was taken using van veen grab sampler from 5 stations based on their position in the estuary. Upon arriving in the laboratory, the samples was washed and sun-dried. The dry sediment samples then were ground and sieved with following mesh sizes, i.e. 0.063, 0.125, and 0.250 mm and put in the plastics sample. The samples of foraminiferan then were hand picking in the picking tray. Classification of planktonic foraminifera is based entirely on the properties of their shells, i.e. wall composition and structure, chamber shape and arrangement, the shape and position of any apertures, surface ornamentation, and other morphologic features of the shell. The present work found 7 genera of planktonic foraminifera from the seafloor of Wulan estuary, i.e. Candeina, Globigerina, Globigerinoides, Globorotalia. Neogloboquadrina, Orbulina, and Pulleniatina. The lowest density was found in the Station 1 (7429 indv.m−2) which was the furthest station from estuary, and the highest density was 7886 indv.m−2 present in Station 3 which was the closest to estuary. Since all seafloor were consisted of silt sediment, these density differences were more influenced by salinity of the water.

scholarly journals PRELIMINARY STUDIES ON SEDIMENT CORE FROM THE TYRO BASIN

2017 ◽  
Vol 50 (1) ◽  
pp. 324
Author(s):  
M. Geraga ◽  
Ch. Anagnostou ◽  
I. Iliopoulos ◽  
M. Kontali
Keyword(s):  
Mediterranean Sea ◽  
Sediment Core ◽  
Eastern Mediterranean ◽  
Planktonic Foraminifera ◽  
Mineralogical Composition ◽  
Eastern Mediterranean Sea ◽  
Sediment Samples ◽  
Preliminary Results ◽  
The Core ◽  
Mineral Constituents

The present paper summarizes the preliminary results of the mineralogical and micropaleontological analysis conducted on sediment samples from core TYR05 retrieved from the anoxic and hypersaline Tyro basin in the eastern Mediterranean Sea. The core comprises a complex lithostratigraphic sequence attributed to the strong geodynamic regime of the area. The planktonic foraminifera associations present fluctuations which coincide with changes in the lithology of the core. The mineralogical composition of the sediments shows influence from the evaporites developed on the bottom of the basin. The mineral constituents in association to the microfauna assemblages suggest that the sediments include sapropelic layers. Further analyses are needed in order to determine safely the sapropelic deposits.

scholarly journals THE DISTRIBUTION CONDITIONS, THE COMPOSITION AND STRUCTURE OF THE SOILS OF THE KHARKOV SUITE OF PALEOGENE OF THE SOUTHEAST OF BELARUS

2019 ◽  
Vol 14 (2) ◽  
pp. 60-73
Author(s):  
O. I. Galeznik ◽  
A. N. Galkin
Keyword(s):  
Statistical Data ◽  
Fine Sand ◽  
Soil Sampling ◽  
Laboratory Studies ◽  
Composition And Structure ◽  
The Republic ◽  
Size And Morphology ◽  
The City

The deposits of the Kharkov suite of Paleogene of Belarus are the soils formed at the turn of existence and regression of the last sea basin and the final establishment of the continental situation in the territory of the country. They are widely spread in the south of the republic and lie mostly at depths of 100–110 m. In the southeast of Belarus, along the valleys of large rivers, these soils often reach the surface. The latter predetermined their active use as the foundations of structures. This is especially pronounced in the city of Gomel, where a wide development of territories is currently underway, within which these soils lie at depths of less than 10 m. The purpose of the work is to characterize the conditions for the distribution of the soils of the Kharkov suite of Paleogene within the southeast of Belarus and to study the characteristics of their composition and structure. The work is based on the results of the author's field and laboratory studies, which included a description of the outcrops, pits, and well cores; soil sampling; determination of their chemical and mineral, granulometric and microaggregate compositions, moisture characteristics for the classification of clay soils, as well as the results of statistical data processing. The paper presents the typification of the soil strata of the Kharkov suite of Paleogene of the southeast of Belarus, which allowed us to isolate three characteristic sites that differ in terms of their distribution, depth, thickness of the strata and composition of the soils. Nine granulometric sand and clay differences within the isolated areas were identified. The study of chemical-mineral and granulometric compositions of soils made it possible to identify their significant changes, both in area and in the section, which is caused by confinement to various facies zones, frequent migration of the coastline, long and uneven erosion and glacier-exaction destruction. The interrelation of the mineral composition, size and morphology of sandy soil particles is analyzed, it is noted that in all their varieties medium and fine sand fractions differ in the greatest mineral diversity.

scholarly journals A case for subgenera in a foraminiferal classification

1990 ◽  
Vol 9 (1) ◽  
pp. 36-36
Author(s):  
D. Graham Jenkins
Keyword(s):  
Amino Acids ◽  
Related Species ◽  
Genetic Information ◽  
Additional Data ◽  
Planktonic Foraminifera ◽  
Similar Test ◽  
Number Of Factors ◽  
Living Species

Abstract. There has been a progression in palaeobiological classifications from the more primitive empirical “stamp collecting” stage where similar shapes were grouped together, to the more sophisticated phylogenetic classifications where supposed genetically related foraminiferal taxa are categorised together. But how do we know that certain extinct taxa were genetically related? This is a major problem where a number of factors interplay together: a belief in evolution, the experience of the operator and consequent recognition of phyletic lineages. In the study of Cenozoic planktonic foraminifera we are fortunate to have recognised a number of now well established lineages; also we have some data on amino-acids found in the tests of living species (King and Hare, 1972) which range back well into the Neogene. These latter data not only provide us with essential genetic information but they also give us confidence when dealing with the classification of extinct species.So how do we build this evolutionary knowledge into a classification? Clearly, genetically related species can be grouped together into subgenera, and related subgenera into broader genera. In their classification Loeblich and Tappan (1988) held a different view and decided not to use subgenera because (1) their usage produces an unwieldy classification, and (2) lineage concepts change when additional data are collected. If we follow their classification, then when you read about Globorotalia menardii, Globorotalia fohsi and Globorotalia hirsuta you could assume that they are closely related; this is not true. The three species have similar test morphologies but these have resulted from iterative. . .

scholarly journals COMMUNITY STRUCTURE OF FORAMINIFERA IN SURFACE SEDIMENTS AND CORRELATION WITH ENVIRONMENTAL CONDITIONS IN OFFSHORE WATERS OF BALIKPAPAN, MAKASSAR STRAIT

2016 ◽  
Vol 7 (2) ◽  
Author(s):  
Suhartati M. Natsir ◽  
Aulya Firman ◽  
Indah Riyantini ◽  
Isni Nurruhwati
Keyword(s):  
Community Structure ◽  
Benthic Foraminifera ◽  
Surface Sediments ◽  
Planktonic Foraminifera ◽  
Sediment Type ◽  
Chemical Parameters ◽  
Sediment Samples ◽  
Sediment Types ◽  
Physical And Chemical Parameters ◽  
Physical And Chemical

The distribution of foraminifera is influenced by several environmental factors such as depth, sediment type, chemical and physical oceanographic paramaters, and season. The aim of the study was to determine the foraminiferal assemblages and their relationship to physical and chemical parameters in the offshore of Balikpapan waters of Makassar Strait such as depth, temperature, currents, sediment types, and salinity. Surface sediment, physical, and chemical parameters sampling was conducted in April 2012. The results of the observations on the sediment samples recognized planktonic foraminifera in 6 genera and 40 genera of benthic foraminifera from the 6 stations. Biodiversity of planktonic foraminifera was categorized in a low category with a range of 0.198-0.525. However, biodiversity for benthic foraminifera was categorized in a high category with a range of 0.811-0.925. Dominance of planktonic foraminifera was medium to high with range of 0.474-0.802 which was assumed due to the sampling sites as an open waters. Meanwhile, dominance for benthic foraminifera was in a low category with range of 0.075-0.189. The most common planktonic foraminifera was found from Genus Globigerina (10538 individuals). While, the most abundant of benthic foraminifera was found from Genus Amphistegina (3134 individuals).  Keywords: abundance, foraminifera, sediment, and Makassar Strait

Species composition and structure of macrophytobenthos in the lower part of the photic zone of the Kolvitsa inlet (Kandalaksha Bay, White Sea)

2017 ◽  
Vol 51 ◽  
pp. 145-156 ◽  
Author(s):  
T. A. Mikhaylova ◽  
A. D. Naumov ◽  
D. A. Aristov
Keyword(s):  
White Sea ◽  
Photic Zone ◽  
Epiphytic Algae ◽  
Kandalaksha Bay ◽  
Composition And Structure ◽  
Red Algal ◽  
Average Biomass ◽  
High Species Richness ◽  
Coccotylus Truncatus ◽  
Species Composition And Structure

The Kolvitsa inlet of the Kandalaksha Bay is a poorly studied part of the White Sea. Sampling was carried out in intertidal and subtidal (using diving equipment) zones from 15 to 21 July 2016. Fifty species of macroalgae were found: 9 species of Chlorophyta, 18 species of Phaeophyceae, and 23 species of Rhodophyta. First records of Choreocolax polysiphoniae and Coccotylus hartzii in the Kandalaksha Bay are reported. The red algal zone at the Kolvitsa inlet extends at the depths from 7 to 17–18 m. Zonation and phytocoenoses with high species richness at the red algal belt were discovered. Community of Odonthalia dentata inhabits the depth of 7–8 m and includes 31 species of seaweeds with their average biomass 282.1 ± 37.6 g/m2; the height of vegetation is 20 cm; Coccotylus truncatus and Polysiphonia stricta are subdominants. Community of C. truncatus inhabits the depths from 8–9 to 11–12 m and includes 35 species of seaweeds with their average biomass 157.4 ± 92.2 g/m2; the height of vegetation is 10 cm; P. stricta, O. dentata and Phycodrys rubens are subdominants. Community of C. truncatus and P. rubens inhabits the depths from 11–12 to 14–15 m and includes 26 species of seaweeds with their average biomass 41.9 ± 1.1 g/m2; the height of vegetation is 5–6 cm; Euthora cristata is a subdominant. Few species of red cortical calcareous algae inhabit the depths from 15 to 18 m. Thirty two epiphytic algae were found. Secondary holdfasts on the erect filaments of Polysiphonia stricta were detected as a specific adaptation for attachment to basiphytes. Most of the epiphytes grow on three species mainly. C. truncatus may be considered as consorcium forming inside the phytocoenoses of the lower part of the photic zone because the biomass of its epiphytes is comparable with that of seaweeds on the ground in the same community.

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