scholarly journals A Chronostratigraphic Framework for the Rise of the Ediacaran Macrobiota: New Constraints from Mistaken Point Ecological Reserve, Newfoundland

Author(s):  
Jack J. Matthews ◽  
Alexander G. Liu ◽  
Chuan Yang ◽  
Duncan McIlroy ◽  
Bruce Levell ◽  
...  

The Conception and St. John’s Groups of southeastern Newfoundland contain some of the oldest known fossils of the Ediacaran macrobiota. The Mistaken Point Ecological Reserve UNESCO World Heritage Site is an internationally recognized locality for such fossils and hosts early evidence for both total group metazoan body fossils and metazoan-style locomotion. The Mistaken Point Ecological Reserve sedimentary succession includes ∼1500 m of fossil-bearing strata containing numerous dateable volcanogenic horizons, and therefore offers a crucial window into the rise and diversification of early animals. Here we present six stratigraphically coherent radioisotopic ages derived from zircons from volcanic tuffites of the Conception and St. John’s Groups at Mistaken Point Ecological Reserve. The oldest architecturally complex macrofossils, from the upper Drook Formation, have an age of 574.17 ± 0.66 Ma (including tracer calibration and decay constant uncertainties). The youngest rangeomorph fossils from Mistaken Point Ecological Reserve, in the Fermeuse Formation, have a maximum age of 564.13 ± 0.65 Ma. Fossils of the famous “E” Surface are confirmed to be 565.00 ± 0.64 Ma, while exceptionally preserved specimens on the “Brasier” Surface in the Briscal Formation are dated at 567.63 ± 0.66 Ma. We use our new ages to construct an age-depth model for the sedimentary succession, constrain sedimentary accumulation rates, and convert stratigraphic fossil ranges into the time domain to facilitate integration with time-calibrated data from other successions. Combining this age model with compiled stratigraphic ranges for all named macrofossils within the Mistaken Point Ecological Reserve succession, spanning 76 discrete fossil-bearing horizons, enables recognition and interrogation of potential evolutionary signals. Peak taxonomic diversity is recognized within the Mistaken Point and Trepassey Formations, and uniterminal rangeomorphs with undisplayed branching architecture appear several million years before multiterminal, displayed forms. Together, our combined stratigraphic, paleontological, and geochronological approach offers a holistic, time-calibrated record of evolution during the mid−late Ediacaran Period and a framework within which to consider other geochemical, environmental, and evolutionary data sets.

2018 ◽  
Vol 16 (5) ◽  
Author(s):  
Rohayah Che Amat

This research presents the value of historic urban landscape (HUL) elements in influencing the character of George Town UNESCO World Heritage Site (WHS), Penang, Malaysia. The values were perceived by the local community of different social-cultural groups that occupied the study area. The historic urban landscape elements constitute towards the protection of its townscape. The identification of the heritage elements influenced by the community interaction with their environment. This study also helps to define the character of a place, as well as reflecting its historical significance. The study adopted four techniques to gather both qualitative and quantitative data, including questionnaire survey, in-depth interview, visual survey and content analysis. In general, the local community has the capability in valuing the historic urban landscape values. The outcomes of their perceptions became the statement of the historic urban landscape values, which are expected to lead to the development of the areas. The community evaluation and perception can be expanded in implementing any development of the historic urban area by the authority.


2021 ◽  
Vol 13 (14) ◽  
pp. 8006
Author(s):  
Till Schmäing ◽  
Norbert Grotjohann

The Wadden Sea ecosystem is unique in many respects from a biological perspective. This is one reason why it is protected by national parks in Germany and by its designation as a UNESCO World Heritage Site. In biology didactics, there are only a few studies that focus on the Wadden Sea. This work investigates students’ word associations with the two stimulus words “national park” and “UNESCO World Heritage Site”. The survey was conducted among students living directly at the Wadden Sea and among students from the inland. The analysis of the identified associations (n = 8345) was carried out within the framework of a quantitative content analysis to be able to present and discuss the results on a group level. A statistically significant difference was found between the two groups. Overall, results showed that the students made subject-related associations as well as a large number of associations to both stimulus words that could be judged as non-subject-related. In some cases, a connection with the region of residence could be found, but this was not generally the case. Even students’ immediate residential proximity to the Wadden Sea is no guarantee that they have knowledge of the two considered protection terms.


Author(s):  
J. Aouissi ◽  
Z. L. Chabaane ◽  
S. Benabdallah ◽  
C. Cudennec

Abstract. The impact of changes in agricultural land use and practices as a controlling driver of hydrologic response and as a source of diffuse pollution, are studied in the Joumine River basin, discharging into the Ichkeul Lake, northern Tunisia, a UNESCO World Heritage site since 1979. The lake is characterized by a very specific hydrological functioning based on a seasonal alternation of water levels and salinity through its link to the Mediterranean Sea. Three Landsat images, in situ surveys and SWAT modelling were used to simulate and assess streamflows and nitrate loads under retrospective land uses.


CivilEng ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 969-985
Author(s):  
Demiana Tse ◽  
João M. Pereira ◽  
Paulo B. Lourenço

Historic monuments and construction capture the knowledge of civilizations of the past and are a source of pride for people of the present. Over the centuries, these buildings have been at risk from natural and man-made causes. The Alhambra, a UNESCO World Heritage Site in Granada, Spain, is one of such places. This paper aims to evaluate the structural performance of the Torre de la Vela, a tower in the Alhambra, under blast loads. The loads were based on historical records of barrels of gunpowder and were modeled as simplified pressure profiles using existing empirical equations. The effect of impulsive loading on the material properties was accounted for using dynamic increase factors, determined experimentally by previous authors. The model was created using finite element methods (FEM) and the problem was solved using explicit dynamic analysis available in Abaqus/Explicit. Using the failure volume damage index, a blast load applied outside and inside of the building would create a low damage level, which should be treated with caution given the occurrence of localized damage. The removal of elements exceeding a given damage threshold led to more visible damage patterns than the Concrete Tension Damage option in Abaqus.


2016 ◽  
Vol 2 (1) ◽  
pp. 26 ◽  
Author(s):  
Julio Bros Williamson ◽  
Jon Stinson ◽  
Alasdair Reid ◽  
John Currie

Resumen Compuestos alternativos en el sector de la envolvente se obtienen por extrusión de estirado de secciones y perfiles de panel de enclavamiento estrechas. Estos elementos estructurales, resistentes al impacto, tienen la ventaja de una instalación más rápida y segura, y su diseño modular les hace idóneos para muchos edificios y otras aplicaciones. Un desarrollo adicional en esta área puede ser la obtención de una alternativa sostenible a los perfiles compuestos actuales. Estudios anteriores han demostrado que los compuestos fabricados a partir de materiales naturales tales como fibras y polímeros bio-derivados, ofrecen una alternativa sostenible a los polímeros y materiales compuestos tradicionales. El objetivo de este desarrollo es reemplazar el típico perfil de acero ligero. Los perfiles de acabado también se pueden utilizar para terminar tabiques de mampostería existentes, revestimiento de ejes mecánicos y de extracción y revestimiento de la columna. Los perfiles se han diseñado utilizando bio-polímeros, reforzados con fibras naturales. Se han establecido los parámetros de procesamiento y las formulaciones apropiadas de bioresina y fibras naturales. También se ha evaluado la adaptación de las técnicas de procesamiento de pultrusión existentes a las características concretas de los nuevos biomateriales y fibras naturales. Como resultado, los perfiles de pultrusión adaptados a la construcción se han desarrollado con la incorporación de nuevos materiales y biomateriales basados en resina. Abstract This paper documents an innovative partnership project between Historic Scotland, the Scottish Energy Centre at Edinburgh Napier University and Castle Rock Edinvar Housing Association in which five Category B Listed, traditional pre-1919, solid wall ‘hard-to-treat’ residential tenement properties located within Edinburgh’s historic UNESCO World Heritage site each received energy efficient upgrades to walls and windows. A variety of measures were tested, achieving significant reductions in fabric heat loss without impacting upon the character and appearance of the buildings. The project is significant in that the energy-efficient upgrades all met with strict conservation requirements on alterations to Listed Buildings and have the potential to be replicated in similar properties throughout Scotland. The project won the award for best refurbishment project at the Carbon Trust’s Low Carbon Building Awards in 2012. All of the properties featured in this study are occupied by tenants within the social-rented sector who prior to the study had indicated some thermal discomfort due to poor window conditions and high heat loss through walls causing increase fuel consumption. The occupants all remained in their homes during the refurbishment activities. 


Author(s):  
Saran S ◽  
Tengis S ◽  
Tsogtbaatar B

The Burkhan Khaldun Mountains (Mongolia) and its surrounding sacred landscape are associated with Genghis Khan’s birth and burial place as described in “The Secret History of the Mongols”. It was listed as a UNESCO World Heritage Site on 4 July 2015 under the title «Great Burkhan Khaldun Mountain and its surrounding sacred landscape.”This study offered a great opportunity to apply the recently developed post-IR infrared luminescence (pIRIR) approach to feldspar using coarse and polymineral fine grain techniques and determine the manufacturing date of a brick sample associated with the ruins of the Buddhist temple at the Burkhan Khaldun Mountains. Furthermore, the mineralogical composition of different blue-grey colored bricks from various temple buildings such as the Buddhist temples in Karakorum, Dugan in Erdene Zuu and Avargyn Balgas were studied. The original place and date of manufacturing of the bricks was revealed using the pIRIR180 and pIRIR240 from coarse and fine grains from a heated feldspar sample and were 1280±40 AD and 1230±50 AD, correspondingly, which falls into the time period of extensive constructions in Karakorum.


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