scholarly journals Distribution and Diversity of Foraminifera in the Northwest of Sarawak Offshore Waters, Malaysia

2019 ◽  
Vol 1 (2) ◽  
pp. 19-25
Author(s):  
Wan Nur Syarah Binti Wan Muhamed Sabri ◽  
Omar Abdula Rahman Abdul Manaf ◽  
Fatin Izzati Minhat
Keyword(s):  
Water Depth ◽  
Benthic Foraminifera ◽  
Surface Sediments ◽  
Sediment Samples ◽  
The Common ◽  
Index Value ◽  
Main Factor

A study on distribution and diversity of benthic foraminifera in surface sediments was carried out in Northwestern Sarawak waters, Malaysia. The range of water depth at the study site was between 43 m and 71 m. A total of seven sediment samples were taken for this study. As a result, 11 genera were identified from a total of 1,222 individuals of foraminifera. 200 individuals were picked out from each sample. The 11 genera that were identified from the study site included Heterolepa spp., Textularia spp., Quinqueloculina spp., Operculina spp. Pseudorotalia spp., Amphistegina spp., Cylindroclavulina spp., Elphidium spp., Ammobaculites spp., Asterorotalia spp. and Bolivina spp.. The common genera found in the sediments of the study areas were Heterolepa, Textularia, Quincoloculina, Operculina and Pseudorotalia. The highest and lowest values of Fisher alpha and Shannon-Wiener indices were shown at Station C287 and Station B482 respectively. The highest value of Fisher alpha was 3.23 and the lowest value was 1.97.  The highest and lowest values of Shannon-Wiener were 2.30 and 1.91. The highest index value of diversity was 3.23 at depth 67.76 m and the lowest value was 1.53 at depth 45.54 m and 68.45 m. From this study, depth is not the main factor that influences the diversity of benthic foraminiferal in northwestern Sarawak waters.

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

scholarly journals DISTRIBUSI FORAMINIFERA BENTIK DI PERAIRAN ACEH

2016 ◽  
Vol 12 (1) ◽  
pp. 25
Author(s):  
Nazar Nurdin ◽  
Imelda R. Silalahi
Keyword(s):  
Indian Ocean ◽  
Water Depth ◽  
Surface Sediment ◽  
Benthic Foraminifera ◽  
Environmental Changes ◽  
Sensitive Indicator ◽  
Sediment Samples ◽  
Strong Current ◽  
Reef Environments ◽  
The Indian Ocean

Perairan Aceh termasuk Pulau Weh, Pulau Breuh dan Pulau Penasi merupakan area terluar di sisi barat Kepulauan Indonesia yang menghadap ke Samudera Hindia. Wilayah ini sangat menarik bagi para peneliti terutama setelah kejadian tsunami pada tahun 2004. Tujuan dari penelitian adalah untuk mengetahui distribusi foraminifera sebagai organisme yang sensitif terhadap perubahan lingkungan. Sebanyak 32 contoh sedimen diambil pada kedalaman 7- 170 meter dan terpilih 11 contoh untuk studi foraminifera. Hasil penelitian menunjukkan bahwa ada 45 spesies foraminifera bentik yang sangat berlimpah, terdiri atas 28 spesies anggota Subordo Rotaliina, Miliolina (7 spesies) dan Textulariina (10 spesies). Amphistegina papilosa dijumpai dalam jumlah sangat berlimpah dan tersebar merata yang memberi indikasi kondisi lingkungan terumbu karang baik. Ammonia tepida sangat dominan (47%) di sebelah utara Pulau Weh (S30) dibandingkan dengan spesies lain. Di bagian Timur Pulau Penasi, ditemukan cangkang foraminifera dalam kondisi rusak dalam jumlah berlimpah yang dapat dikaitkan dengan arus kuat di lokasi ini. Kata kunci : foraminifera bentik, distribusi, perairan Aceh The Aceh waters including Weh, Breuh and Penasi islands are the outer parts of northwestern Indonesia that facing the Indian Ocean. This area is interested for many scientists especially after tsunami in 2004. The purpose of this study is to establish the distribution of benthic foraminifera as a sensitive indicator of environmental changes. Thirty two (32) surface sediment samples were collected at the water depth of 7-170 m and eleven samples were selected for foraminiferal study. The results show 45 species of benthic foraminifera very abundantly and consists of 28 species belong to Suborder Rotaliina, Miliolina (7 species) and Textularia (10 species). Amphistegina papilosa is found abundantly and widely distribution that provide an indication of good reef environments. Ammonia tepida is very dominant(47%) in the northern part of Weh island compared with other species. Abnormal shells of foraminifera were found abundantly in the eastern part of Penasi Island that related to strong current in this area. Keywords: benthic foraminifera, distribution, Aceh waters

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

<p><em>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). </em></p><p><em> </em><strong><em>Keywords:</em></strong><em> abundance, foraminifera, sediment, and Makassar Strait</em></p>

scholarly journals Ocean acidification induces biochemical and morphological changes in the calcification process of large benthic foraminifera

2015 ◽  
Vol 282 (1803) ◽  
pp. 20142782 ◽  
Author(s):  
Martina Prazeres ◽  
Sven Uthicke ◽  
John M. Pandolfi
Keyword(s):  
Ocean Acidification ◽  
Benthic Foraminifera ◽  
Morphological Changes ◽  
Ambient Conditions ◽  
Skeletal Density ◽  
Buoyant Weight ◽  
Large Benthic Foraminifera ◽  
Sediment Formation ◽  
Ph Conditions ◽  
Main Factor

Large benthic foraminifera are significant contributors to sediment formation on coral reefs, yet they are vulnerable to ocean acidification. Here, we assessed the biochemical and morphological impacts of acidification on the calcification of Amphistegina lessonii and Marginopora vertebralis exposed to different pH conditions. We measured growth rates (surface area and buoyant weight) and Ca-ATPase and Mg-ATPase activities and calculated shell density using micro-computer tomography images. In A. lessonii , we detected a significant decrease in buoyant weight, a reduction in the density of inner skeletal chambers, and an increase of Ca-ATPase and Mg-ATPase activities at pH 7.6 when compared with ambient conditions of pH 8.1. By contrast, M. vertebralis showed an inhibition in Mg-ATPase activity under lowered pH, with growth rate and skeletal density remaining constant. While M. vertebralis is considered to be more sensitive than A. lessonii owing to its high-Mg-calcite skeleton, it appears to be less affected by changes in pH, based on the parameters assessed in this study. We suggest difference in biochemical pathways of calcification as the main factor influencing response to changes in pH levels, and that A. lessonii and M. vertebralis have the ability to regulate biochemical functions to cope with short-term increases in acidity.

scholarly journals Sediment Sources and Dispersion on the Western Sunda Shelf, Malay Peninsula, Southern South China Sea

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2823
Author(s):  
Yanguang Liu ◽  
Chuanshun Li ◽  
Ramlan Bin Omar ◽  
Xuefa Shi ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Grain Size ◽  
Surface Sediment ◽  
Surface Sediments ◽  
The Other ◽  
Coarse Grained ◽  
Malay Peninsula ◽  
Sediment Sources ◽  
Southern South China Sea ◽  
Sunda Shelf ◽  
Sediment Samples

Thirty-nine surface sediment samples collected from the western Sunda Shelf off the Malay Peninsula (WSSMP) in the southern South China Sea (SCS) were analysed for grain size, major and trace elemental compositions, and light/heavy mineral contents to trace the sediment sources and their transport mechanisms in the study area. In the WSSMP, the surface sediments are relatively poorly sorted but transportable. A principal component analysis of 37 elements and grain size fractions indicates that the surface sediments can be grouped into four major assemblages in the study area. Integrating with the light/heavy minerals data in the 63–125 μm fractions of the surface sediment samples, to better trace the sediment sources of the coarse-grained components in the marine environment, the study area can be further divided into four sediment provinces. Province I is located in the northwestern part of the study area. The concentrations of TiO2, Na2O, garnet, siderite, and glauconite in Province I were higher than in the other provinces. The main sediment source for this province originated from the Kelantan River and the Gulf of Thailand transported by the northeastern monsoon current. Province II is located offshore of the Pahang and Endau Rivers. The percentages of TiO2, rare earth elements, Al2O3, quartz, plagioclase, hypersthene, and magnetite in the surface sediments were typically higher in this province than in the other provinces. The Pahang and Endau rivers provide most of the sediments to this province, which are transported by southward coastal currents. Province III is located in the northeastern and eastern parts of the study area, where the coarse-grained sediment fraction had relatively high hornblende and biotite contents. Sediments in this province are mostly transported from the Mekong River during the northeastern monsoon. The other parts of the study area belong to Province IV, where the surface sediment elemental and mineral concentrations were mostly between those of the other three provinces. Therefore, we suggest that Province IV has a mixed source due to inputs from the surrounding rivers.

Grain size of surface sediments in Selin Co (central Tibet) linked to water depth and offshore distance

2018 ◽  
Vol 61 (2) ◽  
pp. 217-229 ◽  
Author(s):  
Can Wang ◽  
Hailei Wang ◽  
Gao Song ◽  
Mianping Zheng
Keyword(s):  
Grain Size ◽  
Water Depth ◽  
Surface Sediments ◽  
Central Tibet

Redefining Light Weight Structural Design for Gas Marginal Field Development Through Conductor Supported Platform CSP Concept

2021 ◽  
Author(s):  
Shiiun Bak Wong ◽  
Nur Dalila Alias ◽  
Mohd Kamal Arif ◽  
Majid Shabazi
Keyword(s):  
Water Depth ◽  
Structural Design ◽  
Fast Track ◽  
Low Cost ◽  
Light Weight ◽  
Field Development ◽  
The Past ◽  
Structural Concept ◽  
The Common ◽  
Marginal Field

Abstract The rise of offshore marginal field development and low-cost CAPEX has given an impetus to O&G operators to challenge the common structural platform design especially for wellhead platform type. Demand to reduce the platform weight has been observed for the past 20 years. Typically, the challenge to meet this demand will be tremendous once the water depth exceed 50m. This paper will elaborate on how using an engineered design approach was implemented to obtain fast track onshore fabrication and offshore installation and meet the operator demand for minimal structural concept.

Distribution of scaled chrysophytes in 17 Adirondack (New York) lakes with special reference to pH

1988 ◽  
Vol 66 (7) ◽  
pp. 1391-1403 ◽  
Author(s):  
Peter A. Siver
Keyword(s):  
New York ◽  
Special Reference ◽  
Surface Sediments ◽  
Species Distributions ◽  
Franklin County ◽  
Scaled Chrysophytes ◽  
Bog Lakes ◽  
Adirondack Lakes ◽  
The Common ◽  
Similarities And Differences

Thirty-four scaled chrysophyte taxa are described from 17 Adirondack lakes located in either Hamilton or Franklin counties. Ten taxa, Synura sphagnicola, Syn. echinulata, Syn. petersenii, Mallomonas acaroides var. muskokana, M. hamata, M. caudata, M. crassisquama, M. galeiformis, Spiniferomonas trioralis, and Chrysosphaerella longispina, were found in more than 40% of the study lakes. Mallomonas acaroides var. muskokana, M. hamata, Syn. sphagnicola, Syn. echinulata, and Spiniferomonas coronacircumspina were common and important components of the phytoplankton floras in lakes with a pH < 5.4; however, M. hamata and Sp. coronacircumspina were noticeably absent from bog lakes. Synura sphagnicola and Syn. echinulata were as common in samples with a pH between 5.4 and 7 as they were below pH 5.4. Mallomonas crassisquama, M. caudata, M. pseudocoronata, and Synura spinosa were found in a significantly greater percentage of samples from circumneutral lakes and were lacking from waters with a pH < 5.4. Differences in species distributions between Hamilton County (higher mean pH) and Franklin County lakes further supported the observed pH ranges of the common taxa. Similarities and differences are made with a study of Smol et al. (Can. J. Bot. 62: 911–923), who described the distribution of scaled chrysophytes from the surface sediments of Adirondack lakes.

scholarly journals Economically optimal water depth and grain yield of common bean subjected to different irrigation depths

2018 ◽  
Vol 22 (7) ◽  
pp. 482-487 ◽  
Author(s):  
Chaiane G. da Conceição ◽  
Adroaldo D. Robaina ◽  
Marcia X. Peiter ◽  
Ana R. C. Parizi ◽  
João A. da Conceição ◽  
...  
Keyword(s):  
Grain Yield ◽  
Common Bean ◽  
Technical Efficiency ◽  
Water Depth ◽  
Critical Periods ◽  
Crop Evapotranspiration ◽  
Randomized Design ◽  
The Common ◽  
Completely Randomized Design ◽  
Bean Crop

ABSTRACT Common bean crop plays an important role in the world, not only in economic aspects but also in social development. The objective of this study was to evaluate the grain yield and the economically optimal water depth which reflects the maximum technical efficiency of the common bean crop. The experiment was conducted in greenhouse, in Alegrete - RS, from February to May 2016. A completely randomized design was used, consisting of five water replacement treatments (25, 50, 75, 100 and 125% crop evapotranspiration - ETc) and four replicates. Based on the obtained results, both water deficit and water excess directly affected the final grain yield of the crop. Maximum grain yield was 3,554.1 kg ha-1, obtained by applying 492.72 mm (100% ETc). On the other hand, the economically optimal water depth was estimated at 91.2% ETc, indicating that water depths above this value are not suitable for maximum technical efficiency in the common bean crop under these conditions. It was concluded that the water depth equivalent to 100% ETc maximizes grain yield for the region of Alegrete-RS, and irrigation is considered a solution in the water supply to the common bean crop during critical periods.

scholarly journals Biological Aspects of Juveniles of the Common Stingray, Dasyatis pastinaca (Linnaeus, 1758) (Elasmobranchii, Dasyatidae), from the Central Mediterranean Sea

2020 ◽  
Vol 8 (4) ◽  
pp. 269
Author(s):  
Francesco Tiralongo ◽  
Giuseppina Messina ◽  
Bianca Maria Lombardo
Keyword(s):  
Mediterranean Sea ◽  
Stomach Contents ◽  
Ionian Sea ◽  
Central Mediterranean ◽  
Disc Width ◽  
Ecological Aspects ◽  
Central Mediterranean Sea ◽  
The Common ◽  
Biological Aspects ◽  
Index Value

Data on the biology of Dasyatis pastinaca are absent from the Ionian Sea and only a few studies were conducted in the Mediterranean Sea. Some biological and ecological aspects of D. pastinaca were investigated between November 2019 and February 2020 in the central Mediterranean Sea. In particular, we investigated several morphologic, population and ecological aspects of the species. The analysis of the stomach contents showed that D. pastinaca is a generalist carnivorous, mainly feeding on small crustaceans and polychaetes. The Levin’s index value (Bi) was 0.85. The sex ratio showed no significant differences from 1:1 ratio. Females were larger than males, but no statistical differences were found in disc width-weight and total length-disc width relationships between sexes. Most of the specimens caught were juveniles and inhabit shallow sandy bottoms.

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