scholarly journals Reviews and syntheses: <sup>210</sup>Pb-derived sediment and carbon accumulation rates in vegetated coastal ecosystems: setting the record straight

2018 ◽  
Author(s):  
Ariane Arias-Ortiz ◽  
Pere Masqué ◽  
Jordi Garcia-Orellana ◽  
Oscar Serrano ◽  
Inés Mazarrasa ◽  
...  
Keyword(s):  
210Pb Dating ◽  
Coastal Ecosystems ◽  
Carbon Accumulation ◽  
Coastal Sediments ◽  
Geochemical Data ◽  
Accumulation Rates ◽  
Sediment Organic Carbon ◽  
The Status ◽  
Heterogeneous Sediments

Abstract. Vegetated coastal ecosystems, including tidal marsh, mangrove and seagrass, are being increasingly assessed for their potential in carbon dioxide sequestration worldwide. However, there is a paucity of studies that have effectively estimated the accumulation rates of sediment organic carbon (Corg) beyond the mere quantification of Corg stocks. Here, we discuss the use of the 210Pb dating technique as a practical tool to measure the rate of Corg accumulation in vegetated coastal ecosystems. We critically review the status of 210Pb dating methods of vegetated coastal sediments and assess the limitations that apply to these ecosystems, which are often composed by heterogeneous sediments, abundant in coarse particles, with varying inputs of organic material, and are disturbed by natural and anthropogenic processes causing sediment mixing, changes in sedimentation rates or erosion. Through a range of simulations, we discuss the most relevant processes that impact the 210Pb record in vegetated coastal ecosystems and evaluate the deviations in sediment and Corg accumulation rates produced by anomalies in 210Pb profiles. Our results show that the deviation in the determination of sediment and derived Corg accumulation rates is within 20 % confirming that the 210Pb dating technique is secure. However, while these uncertainties might be acceptable for the determination of mean sediment and Corg accumulation rates over the last century, they may not always allow the determination of a detailed geochronology, historical reconstruction, or to ascertain rates of change and fluxes. Additional tracers or geochemical data need to be used in concert to constrain the 210Pb-derived results and to properly interpret the processes recorded in vegetated coastal sediments. The framework provided in this study can be instrumental in reducing the uncertainties associated to the estimates of Corg accumulation rates in vegetated coastal sediments.

scholarly journals Reviews and syntheses: <sup>210</sup>Pb-derived sediment and carbon accumulation rates in vegetated coastal ecosystems – setting the record straight

2018 ◽  
Vol 15 (22) ◽  
pp. 6791-6818 ◽  
Author(s):  
Ariane Arias-Ortiz ◽  
Pere Masqué ◽  
Jordi Garcia-Orellana ◽  
Oscar Serrano ◽  
Inés Mazarrasa ◽  
...  
Keyword(s):  
Specific Activity ◽  
210Pb Dating ◽  
Coastal Ecosystems ◽  
Carbon Accumulation ◽  
Coastal Sediments ◽  
Tidal Marshes ◽  
Accumulation Rates ◽  
Seagrass Meadows ◽  
Sediment Organic Carbon ◽  
Heterogeneous Sediments

Abstract. Vegetated coastal ecosystems, including tidal marshes, mangroves and seagrass meadows, are being increasingly assessed in terms of their potential for carbon dioxide sequestration worldwide. However, there is a paucity of studies that have effectively estimated the accumulation rates of sediment organic carbon (Corg), also termed blue carbon, beyond the mere quantification of Corg stocks. Here, we discuss the use of the 210Pb dating technique to determine the rate of Corg accumulation in these habitats. We review the most widely used 210Pb dating models to assess their limitations in these ecosystems, often composed of heterogeneous sediments with varying inputs of organic material, that are disturbed by natural and anthropogenic processes resulting in sediment mixing and changes in sedimentation rates or erosion. Through a range of simulations, we consider the most relevant processes that impact the 210Pb records in vegetated coastal ecosystems and evaluate how anomalies in 210Pb specific activity profiles affect sediment and Corg accumulation rates. Our results show that the discrepancy in sediment and derived Corg accumulation rates between anomalous and ideal 210Pb profiles is within 20 % if the process causing such anomalies is well understood. While these discrepancies might be acceptable for the determination of mean sediment and Corg accumulation rates over the last century, they may not always provide a reliable geochronology or historical reconstruction. Reliable estimates of Corg accumulation rates might be difficult at sites with slow sedimentation, intense mixing and/or that are affected by multiple sedimentary processes. Additional tracers or geochemical, ecological or historical data need to be used to validate the 210Pb-derived results. The framework provided in this study can be instrumental in reducing the uncertainties associated with estimates of Corg accumulation rates in vegetated coastal sediments.

The Validity of Rector�s Circular Letter on the Covid-19 Pandemic

2020 ◽  
Vol 7 (1) ◽  
pp. 126 ◽  
Author(s):  
Fradhana Putra Disantara
Keyword(s):  
Legal Theory ◽  
Legal Issues ◽  
State Universities ◽  
Ministry Of Education ◽  
Conceptual Approach ◽  
State Of Emergency ◽  
Circular Letter ◽  
The Status ◽  
The Government

This study aims to analyze the relevance of the �health emergency� status to the existing legal theory and condition as well as to identify the validity of the Circular Letter of the Rector of State Universities. To this end, this study applied the statute and conceptual approach. The study was conducted by inventorying primary and secondary legal materials to obtain a proper and critical review of the legal issues under study. The results showed that the determination of the �health emergency� status by the government was inappropriate due to the uncertainty of the regulations issued by the government to determine the current condition. Thus, the status of the COVID-19 pandemic is a �legal emergency� status. Further, the Rector�s policy through the Circular Letter is valid judicially, sociologically, and philosophically. The determination of the �legal emergency� status can be done by issuing a Perppu without a �state of emergency� from the President. Finally, it is suggested to firstly get an approval from the Ministry of Education and Culture regarding the issuance of the Rector�s Circular Letter. Besides, further study is needed as this study was conducted during the COVID-19 pandemic.�Keabsahan Surat Edaran Rektor Perguruan Tinggi dalam Pandemi Covid-19Tujuan dari penelitian ini adalah untuk menganalisa relevansi status �darurat kesehatan� dengan teori hukum dan kondisi yang ada dan keabsahan atas Surat Edaran Rektor Perguruan Tinggi Negeri. Metode yang digunakan dalam penelitian ini adalah statute approach dan conseptual approach. Penelitian dilakukan dengan menginventarisasi bahan hukum primer dan sekunder, guna mendapatkan kajian yang seyogianya dan telaah kritis terkait isu hukum. Hasil penelitian menyatakan penetapan status darurat kesehatan oleh pemerintah kurang tepat, dikarenakan tidak menentu-nya peraturan yang dikeluarkan oleh pemerintah untuk menetapkan kondisi saat ini. Sehingga, status pandemi COVID-19 merupakan status darurat hukum. Kebijakan rektor melalui Surat Edaran adalah absah secara aspek yuridis, sosiologis, dan filosofis. Penetapan darurat hukum cukup dilakukan dengan menerbitkan Perppu tanpa pernyataan darurat dari Presiden. Saran peneliti adalah di perlukan persetujuan pada Kementerian Pendidikan dan Kebudayaan terkait terbitnya Surat Edaran Rektor, dan dibutuhkan penelitian lebih lanjut dikarenakan penelitian ini dilakukan pada masa COVID-19 yang bersifat temporal.�

The determination of sedimentation rates in Lake Ontario using the 210Pb dating method

1978 ◽  
Vol 15 (3) ◽  
pp. 431-437 ◽  
Author(s):  
John G. Farmer
Keyword(s):  
Sedimentation Rate ◽  
Lake Ontario ◽  
Sedimentary Basins ◽  
210Pb Dating ◽  
Sedimentation Rates ◽  
Surface Mixing ◽  
Dating Method ◽  
210Pb Dating Method

The 210Pb dating method has been applied successfully to the determination of recent sedimentation rates at four sites distributed among the three major sedimentary basins (Niagara, Mississauga and Rochester) of Lake Ontario. Following correction for effects due to compaction of the sediments, mean sedimentation rates ranging from 0.02 cm/year at the periphery of the Mississauga basin to 0.11 cm/year in the Niagara and Rochester basins were determined. Allowance for compaction reduced the non-compaction-corrected sedimentation rates by 20–35%. Neither 210Pb nor fallout 137Cs profiles indicated surface mixing of sediment sufficient to noticeably affect the calculated sedimentation rates. At all four sites, the sedimentation rate seems to have remained constant during the last 100–150 years.

Carbon accumulation rates recorded in the last 150 years in tropical high mountain peatlands of the Atlantic Rainforest, SE - Brazil

2017 ◽  
Vol 579 ◽  
pp. 439-446 ◽  
Author(s):  
Lúcio F. Lourençato ◽  
Pedro P. Caldeira ◽  
Marcelo C. Bernardes ◽  
Andressa C. Buch ◽  
Daniel C. Teixeira ◽  
...  
Keyword(s):  
Carbon Accumulation ◽  
Atlantic Rainforest ◽  
High Mountain ◽  
Accumulation Rates ◽  
Se Brazil ◽  
Carbon Accumulation Rates ◽  
Mountain Peatlands

Why Repentance Affects Divine Punishment but Not Human Punishment?

2015 ◽  
Vol 4 (1) ◽  
pp. 96-115
Author(s):  
Shoval Shafat
Keyword(s):  
Criminal Law ◽  
Human Beings ◽  
The Status ◽  
Divine Punishment ◽  
Divine Mercy ◽  
Rabbinic Courts

The aim of the discussion in this article is to explore two different Rabbinic explanations for the status of repentance in human and divine punishment, and to emphasize the essential distinction between them. According to the first explanation the source of accepting repentance is divine mercy upon human beings. Since mercy is not a legitimate consideration in conviction or even in determination of punishment in Jewish criminal law there is no wonder why repentance does not have any role during the criminal procedures in rabbinic court. According to the second explanation the acceptance of repentance by God is similar to the acceptance of flattery and bribe by a Roman corrupted judge. God decides to accept repentance and to forgive the transgressors since it better serves God’s interests. This analogy between repentance and flattery and bribery then explains why rabbinic courts do not take repentance into account.

scholarly journals Methods for Structural Stress Determination according to EN 13445-3 Annex NA – Comparison with other Codes for Unfired Pressure Vessels

2018 ◽  
Vol 165 ◽  
pp. 10003
Author(s):  
Ralf Trieglaff ◽  
Jürgen Rudolph ◽  
Martin Beckert ◽  
Daniel Friers
Keyword(s):  
Pressure Vessel ◽  
Pressure Vessels ◽  
Structural Stress ◽  
Stress Determination ◽  
User Friendliness ◽  
Fatigue Assessment ◽  
Shell Elements ◽  
European Working ◽  
The Status

The European Pressure Vessel Standard EN 13445 provides in its part 3 (Design) a simplified method (Clause 17) and a detailed method for fatigue assessment (Clause 18). Clause 18 “Detailed Assessment of Fatigue Life” is under revision within the framework of the European working group CEN/TC 54/WG 53 – Design methods with the aim of reaching a significant increase in user-friendliness and a clear guideline for the application. This paper is focused on the new informative annex NA ”Instructions for structural stress oriented finite elements analyses using brick and shell elements”. As an essential amendment for the practical user, the determination of structural stress ranges for fatigue assessment of welds is further specified in this new annex. Different application methods for the determination of structural stresses are explained in connection with the requirements for finite element models and analyses. This paper will give a short overview of the proposed approaches of structural stress determination in annex NA of the revised EN 13445-3. It will present the status of the approaches based on the results of fatigue analyses according to EN 13445-3 Clause 18 for different application examples. For verification purposes, the results of the approaches proposed in EN 13445-3 are compared with the results of other pressure vessel design codes for nuclear and non-nuclear application.

scholarly journals ПОЛІТИКО-ПРАВОВІ АСПЕКТИ ЗАКОНОДАВЧОГО ЗАБЕЗПЕЧЕННЯ ВИБОРЧОГО ПРОЦЕСУ В СУЧАСНІЙ УКРАЇНІ

2019 ◽  
pp. 134-144
Author(s):  
Г. М. Нечаєва
Keyword(s):  
State Power ◽  
Legal Regulation ◽  
Electoral Process ◽  
Public Authorities ◽  
The Status ◽  
The Will ◽  
Points Of View ◽  
Democratic Principles ◽  
The Stability

This article examines the stages of the electoral process based on the legislation of Ukraine on elections since the proclamation of independent Ukraine until now. Considerable attention is paid to the disclosure of the concept of "electoral process", since democracy and the legitimacy of the entire system of public authorities depend to the electoral democracy. On the basis of various points of view of scientists, scholars of lawyers it can be concluded that the electoral process as a legal category is an independent legal institution of constitutional law, which should be understood as a set of constitutional and procedural norms governing the formation of representative bodies of the state and other elected bodies of state power and bodies of local self-government, election of state officials. The issue of the legislative support of the electoral process in Ukraine, the problem of the formation of a system of electoral legislation in Ukraine on the basis of which the electoral process takes place - elections of the President of Ukraine, people's deputies of Ukraine, deputies of local councils and village, town and city mayors. Adequate reflection of the will of the citizens on the formation of a system of government, the creation of conditions for free and deliberate expression of will require not only the legislative consolidation of the principles of free and fair elections, but also detailed legal regulation of procedures for conducting an election campaign, determination of the status of the subjects of the electoral process, their rights and obligations defining the results of elections, etc. The necessity of formation and establishment of a stable electoral culture of voters and the stability of electoral legislation for ensuring the proper realization of the electoral rights of Ukrainian citizens is indicated. However, the main problem is not so much in adopting laws that would comply with generally accepted democratic principles, but in ensuring compliance with these principles in practice, which does not always lie in the field of legislative regulation. In order to ensure legality in the process of organizing and holding elections, the functioning and interaction of all branches of state power, local self-government bodies and public associations must be agreed upon.

scholarly journals Job Quality and Gender Inequality: Key Changes in Québec over the Last Decade

2010 ◽  
Vol 3 (2) ◽  
pp. 191-212 ◽  
Author(s):  
Luc Cloutier ◽  
Paul Bernard ◽  
Diane-Gabrielle Tremblay
Keyword(s):  
Higher Education ◽  
Gender Inequality ◽  
Labour Force ◽  
Significant Decline ◽  
Job Quality ◽  
Labour Force Survey ◽  
The Status ◽  
And Gender ◽  
Status Of Women

Using a new typology based on information available from the Labour Force Survey, the authors analyse how job quality evolved in Québec for both women and men over the last decade (1997-2007). Results show that family situation and educational attainment are two important factors in the determination of gender inequality in the labour market. The analysis emphasizes the very significant decline in gender differences with regard to job quality (from 23% to 35% according to groups), especially for persons without children and individuals who achieved higher education. The changes represent a definite progress in the status of women in general, although some indicators also reveal degradation with respect to job quality in some of the sub-groups.  

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