Heavy mineral record of Andean uplift and changing sediment sources across the NE margin of South America: a case study from Trinidad and Barbados

2014 ◽  
Vol 386 (1) ◽  
pp. 217-241 ◽  
Author(s):  
Hasley Vincent ◽  
Grant Wach ◽  
Yawooz Ketannah
Keyword(s):  
South America ◽  
Heavy Mineral ◽  
Sediment Sources ◽  
Andean Uplift

Poe and His Global Advocates

2018 ◽  
pp. 596-617
Author(s):  
Emron Esplin
Keyword(s):  
Twentieth Century ◽  
South America ◽  
Rio De La Plata ◽  
Río De La Plata ◽  
Literary Traditions ◽  
La Plata ◽  
Original Works ◽  
Definition Of ◽  
Global Reputation

This essay explores Edgar Allan Poe’s extraordinary relationships with various literary traditions across the globe, posits that Poe is the most influential US writer on the global literary scene, and argues that Poe’s current global reputation relies at least as much on the radiance of the work of Poe’s literary advocates—many of whom are literary stars in their own right—as it does on the brilliance of Poe’s original works. The article briefly examines Poe’s most famous French advocates (Baudelaire, Mallarmé, Valéry); glosses the work of his advocates throughout Europe, Asia, and the Americas; and offers a concise case study of Poe’s influence on and advocacy from three twentieth-century writers from the Río de la Plata region of South America (Quiroga, Borges, and Cortázar). The essay concludes by reading the relationships between Poe and his advocates through the ancient definition of astral or stellar influence.

scholarly journals Ecological research should consider Indigenous peoples and stewardship

FACETS ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 534-537
Author(s):  
Kyle A. Schang ◽  
Andrew J. Trant ◽  
Sara A. Bohnert ◽  
Alana M. Closs ◽  
Megan Humchitt ◽  
...  
Keyword(s):  
South America ◽  
Indigenous Peoples ◽  
Terrestrial Ecosystems ◽  
Ecological Research ◽  
Indigenous Groups ◽  
Indigenous Group ◽  
Indigenous Territories ◽  
America South ◽  
The Relationship

The relationship between Indigenous peoples and the functioning of terrestrial ecosystems has received increased attention in recent years. As a result, it is becoming more critical for researchers focusing on terrestrial ecosystems to work with Indigenous groups to gain a better understanding of how past and current stewardship of these lands may influence results. As a case study to explore these ideas, we systematically reviewed articles from 2008 to 2018 where research was conducted in North America, South America, and Oceania. Of the 159 articles included, 11 included acknowledgement of Indigenous stewardship, acknowledged the Indigenous Territories or lands, or named the Indigenous group on whose Territory the research was conducted. Within the scope of this case study, our results demonstrate an overall lack of Indigenous acknowledgement or consideration within the scope of our review. Given the recent advancements in our understanding of how Indigenous groups have shaped their lands, we implore researchers to consider collaboration among local Indigenous groups as to better cultivate relationships and foster a greater understanding of their ecosystems.

scholarly journals Transformation and aging of biomass burning carbonaceous aerosol over tropical South America from aircraft in-situ measurements during SAMBBA

2019 ◽  
Author(s):  
William T. Morgan ◽  
James D. Allan ◽  
Stéphane Bauguitte ◽  
Eoghan Darbyshire ◽  
Michael J. Flynn ◽  
...  
Keyword(s):  
South America ◽  
Biomass Burning ◽  
Chemical Properties ◽  
Carbonaceous Aerosol ◽  
Air Masses ◽  
Atmospheric Aging ◽  
Primary Driver ◽  
Tropical South America

Abstract. We present a range of airborne in-situ observations of biomass burning carbonaceous aerosol over tropical South America, including a case study of a large tropical forest wildfire and a series of regional survey flights across the Brazilian Amazon and Cerrado. The study forms part of the South American Biomass Burning Analysis (SAMBBA) Project, which was conducted during September and October 2012. We find limited evidence for net increases in aerosol mass through atmospheric aging combined with substantial changes in the chemical properties of organic aerosol (OA). Oxidation of the OA increases significantly and rapidly on the scale of 2.5–3 hours based on our case study analysis and is consistent with secondary organic aerosol production. The observations of limited net enhancement in OA coupled with such changes in chemical composition, imply that evaporation of OA is also occurring to balance these changes. We observe significant coatings on black carbon particles at source, but with limited changes with aging in both particle core size and coating thickness. We quantify variability in the ratio of OA to carbon monoxide across our study as a key parameter representing both initial fire conditions and an indicator of net aerosol production with atmospheric aging. We observe ratios of 0.075–0.13 μg sm−3 ppbv−1 in the west of our study region over the Amazon tropical forest in air masses less influenced by precipitation and a value of 0.095 μg sm−3 ppbv−1 over the Cerrado environment in the east. Such values are consistent with emission factors used by numerical models to represent biomass burning OA emissions. Black carbon particle core sizes typically range from 250–290 nm, while coating thicknesses range from 40–110 nm in air masses less influenced by precipitation. The primary driver of the variability we observe appears to be related to changes at the initial fire source. A key lesson from our study is that the complex nature of the regional aerosol and its drivers precludes aggregating our observations as a function of atmospheric aging due to the many conflating and competing factors present. Our study explores and quantifies key uncertainties in the evolution of biomass burning aerosol at both nearfield and regional scales. Our results suggest that the initial conditions of the fire are the primary driver of carbonaceous aerosol physical and chemical properties over tropical South America, aside from significant oxidation of OA during atmospheric aging. Such findings imply that uncertainties in the magnitude of the aerosol burden and its impact on weather, climate, health and natural ecosystems most likely lie in quantifying emission sources, alongside atmospheric dispersion, transport and removal rather than chemical enhancements in mass.

Molecular phylogenetics and evolution of the food relocation behaviour of the dung beetle tribe Eucraniini (Coleoptera:Scarabaeidae:Scarabaeinae)

2006 ◽  
Vol 20 (5) ◽  
pp. 557 ◽  
Author(s):  
Federico C. Ocampo ◽  
David C. Hawks
Keyword(s):  
Phylogenetic Analysis ◽  
South America ◽  
Molecular Phylogeny ◽  
Plant Material ◽  
Molecular Phylogenetics ◽  
Middle Miocene ◽  
Dung Beetle ◽  
Sister Group ◽  
Vicariant Event ◽  
Andean Uplift

A phylogenetic analysis using 28S and 18S rDNA provides evidence that the tribe Eucraniini is a monophyletic group and the sister-group of the Phanaeini and Dichotomiini. Our molecular phylogeny of the dung beetle tribes provides strong evidence for the monophyly of the subfamily Scarabaeinae. The monophyly of the tribe Eucraniini is well supported and it includes the genera Anomiopsoides Blackwelder, Ennearabdus van Lansberge, Eucranium Brullé and Glyphoderus Westwood. The food-lifting relocation behaviour present in species of Eucranium, Anomiopsoides and Glyphoderus is considered a derived condition and it most probably evolved from tunnelling behaviour. The preference for dry dung or dung pellets by species of Eucraniini genera, and feeding on plant material by species of Anomiopsoides, are considered apomorphic. Our analyses suggest that rolling behaviour in the Scarabaeinae evolved at least twice during their evolution. The incidence of high endemicity of dung beetles in the Monte biogeographic province of Argentina suggests that the area constitutes an independent centre of evolution. Our hypothesis is that a vicariant event was responsible for the divergence of the Eucraniini from a Neotropical lineage ancestral to Eucraniini and Phanaeini. The isolation of the Eucraniini lineage probably occurred after the Andean uplift during the Quechua diastrophism (middle Miocene) that resulted in the creation of xeric plains in austral regions of South America.

Effect of the lithospheric thermal state on the Moho interface: A case study in South America

2017 ◽  
Vol 76 ◽  
pp. 198-207 ◽  
Author(s):  
Mohammad Bagherbandi ◽  
Yongliang Bai ◽  
Lars E. Sjöberg ◽  
Robert Tenzer ◽  
Majid Abrehdary ◽  
...  
Keyword(s):  
South America ◽  
Thermal State ◽  
Moho Interface
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