scholarly journals The Southern Ocean Radiolarian (SO-RAD) dataset: a new compilation of modern radiolarian census data

2021 ◽  
Vol 13 (11) ◽  
pp. 5441-5453
Author(s):  
Kelly-Anne Lawler ◽  
Giuseppe Cortese ◽  
Matthieu Civel-Mazens ◽  
Helen Bostock ◽  
Xavier Crosta ◽  
...  

Abstract. Radiolarians (holoplanktonic protozoa) preserved in marine sediments are commonly used as palaeoclimate proxies for reconstructing past Southern Ocean environments. Generating reconstructions of past climate based on microfossil abundances, such as radiolarians, requires a spatially and environmentally comprehensive reference dataset of modern census counts. The Southern Ocean Radiolarian (SO-RAD) dataset includes census counts for 238 radiolarian taxa from 228 surface sediment samples located in the Atlantic, Indian, and southwest Pacific sectors of the Southern Ocean. This compilation is the largest radiolarian census dataset derived from surface sediment samples in the Southern Ocean. The SO-RAD dataset may be used as a reference dataset for palaeoceanographic reconstructions, or for studying modern radiolarian biogeography and species diversity. As well as describing the data collection and collation, we include recommendations and guidelines for cleaning and subsetting the data for users unfamiliar with the procedures typically used by the radiolarian community. The SO-RAD dataset is available to download from https://doi.org/10.1594/PANGAEA.929903 (Lawler et al., 2021).

2021 ◽  
Author(s):  
Kelly-Anne Lawler ◽  
Giuseppe Cortese ◽  
Matthieu Civel-Mazens ◽  
Helen Bostock ◽  
Xavier Crosta ◽  
...  

Abstract. Radiolarians (holoplanktonic Protozoa) preserved in marine sediments are commonly used as palaeoclimate proxies for reconstructing past Southern Ocean environments. Generating reconstructions of past climate based on microfossil abundances, such as radiolarians, requires a spatially and environmentally comprehensive reference dataset of modern census counts. The Southern Ocean RADiolarian (SO-RAD) dataset includes census counts for 238 radiolarian taxa from 228 surface sediment samples located in the Atlantic, Indian and southwest Pacific sectors of the Southern Ocean. This compilation is the largest radiolarian census dataset derived from surface sediment samples in the Southern Ocean. The SO-RAD dataset may be used as a reference dataset for palaeoceanographic reconstructions, or for studying modern radiolarian biogeography and species diversity. As well as describing the data collection and collation, we include recommendations and guidelines for cleaning and subsetting the data for users unfamiliar with the procedures typically used by the radiolarian community. The SO-RAD dataset is available to download from doi.pangaea.de/10.1594/PANGAEA.929903 (Lawler et al., 2021).


1984 ◽  
Vol 19 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Alena Mudroch

Abstract Surface sediment samples obtained at the offshore and nearshore area of Lake Erie were separated into eight different size fractions ranging from <2 µm to 250 µm. The concentration of major elements (Si, Al, Ca, Mg, K, Na, Fe, Mn and P), metals (Zn, Cu, Cr, Ni, V, Co and Pb) and organic matter was determined together with the mineralogical composition and morphology of the particles in each size fraction. The distribution of the metals in the offshore sediment was bimodal with the majority of the metals divided between the 63 to 250 um size fraction which also contained the highest concentration of organic matter (about 20%) and the <4 µm fraction containing up to 60% of clay minerals. However, the metals in the nearshore sediment were associated mainly with the clay minerals.


Author(s):  
Nurkhalik Wahdanial Asbara

Technological developments and changes in government systems are developing rapidly. Both of these lead to efforts to carry out duties, protect functions and serve the community. This encourages the government to take various adjustment steps quickly in line with the dynamics of development that occur. One of them is through a population census. The population census is an important issue that must be handled properly. The population census in this study takes population data in an area based on the number of male population, female population, ratio, and population density. The data was taken and submitted to the Makassar City Statistics Agency. Population Census is a presentation of information that has the ability to present accurate information, and helps facilitate the search for a population census data. The population census is carried out every 5 years which is carried out by census officers to carry out data collection to each resident's house, the data collection process is carried out by conventional recording and submitting it to the central statistics agency for database entry. With this application, it is expected to provide convenience to Population census officers to perform the process of inputting population data and the data is directly stored in the database without having to return to the office to input again.


2019 ◽  
Vol 9 (1) ◽  
pp. 57
Author(s):  
Muhammad Azis ◽  
Anismawardani Bakri ◽  
Darman Manda

This study aims to determine the effect of educational qualifications, years of service, and school climate on the performance of economic teachers in SMKs throughout Makassar. The type of this research is Expo-Facto research with Population are all economic teachers of Vocational High Schools in Makassar City. The sampling technique uses a saturated sampling technique (census). Data collection techniques are questionnaires, observation and documentation. The results show that (1) There is a direct influence of educational qualifications on the school climate on the performance of economic teachers, (2) There is a significant positive direct effect on the working period on the school climate on economic teacher performance, (3) There is a significant direct influence on economic teacher performance, (4) There is a direct influence on the work period on the performance of economic teachers, (5) There is a direct influence of the school climate on the performance of economic teachers, (6) There is an indirect influence of education qualifications through the school climate on economic teacher performance (7) There is an indirect influence on the working period through the school climate on the performance of economic teachers.


Author(s):  
Hung Duc Nguyen ◽  
Ngot Van Pham ◽  
Duy Van Nguyen

This study was conducted to investigate the physio-chemical properties and vertical dynamic of the surface sediment (0–5 cm) in riparian mangroves along the Tien river, Tien Giang province. The distribution of riparian mangroves located from the polyhaline zone (transect S1 and S2) to the mesohaline zone (transect S3 and S4) and the oligohaline zone (transect S5). Three plots (10x10 m) per transect were set based on the elevation of the mangrove floor (cm + mean sea level) and dominant plants. A total of 28 sediment samples were collected in December 2016 and April 2017. Seasonal variation of pH, redox potential (Eh), electrical conductivity of saturated extract (ECse), bulk density, sediment organic matter (SOM) and total sulfur (TS) were measured in accordance with the standard protocols. Seasonal trends of vertical erosion and accumulation were tested by the tracer stick method. The ECse values and TS concentrations were higher in the dry season and in transects closed to the estuary (S1, S2 and S3) but these trends weren’t found for pH, Eh, and SOM. In most of the riparian mangroves along the Tiền river, low elevation (0–50 cm) was one of important factors affecting the Eh and ECse. In the rainy season, major changes in vertical erosion and acumulation have occurred in the transects near the mouth of the river.


Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2823
Author(s):  
Yanguang Liu ◽  
Chuanshun Li ◽  
Ramlan Bin Omar ◽  
Xuefa Shi ◽  
Hui Zhang ◽  
...  

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.


Author(s):  
Frank M. Weerman ◽  
Evelien Hoeben ◽  
Wim Bernasco ◽  
Lieven J. R. Pauwels ◽  
Gerben J.N. Bruinsma

This chapter addresses methods to study situational influences of setting characteristics on adolescent offending. In particular, it describes data collection methods (space-time budget interviews, census data, community surveys, and systematic social observations) that enable precise measurement of what respondents do, with whom they undertake these activities, and in what kind of places (both the geographical area and the function of the location) they find themselves. Such data capture presence in and exposure to different kinds of settings during particular periods in time. This chapter illustrates the usefulness of these method for criminological research by summarizing the results of three sub-studies from the Study of Peers, Activities, and Neighborhoods (SPAN) conducted in the Netherlands. It first discusses the design of the SPAN data collection and the instruments that were used in it. It then reviews each study in turn by summarizing its theoretical motivation, data structure, and analytical strategy, and by describing the main findings it has generated.


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