guiana shield
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2022 ◽  
Vol 14 (1) ◽  
pp. 224
Author(s):  
Jessica Bechet ◽  
Tommy Albarelo ◽  
Jérémy Macaire ◽  
Maha Salloum ◽  
Sara Zermani ◽  
...  

Increasing the utilization of renewable energy is at the center of most sustainability policies. Solar energy is the most abundant resource of this type on Earth, and optimizing its use requires the optimal estimation of surface solar irradiation. Heliosat-2 is one of the most popular methods of global horizontal irradiation (GHI) estimation. Originally developed for the Meteosat satellite, Heliosat-2 has been modified in previous work to deal with GOES-13 data and named here GOES_H2. This model has been validated through the computation of indicators and irradiation maps for the Guiana Shield. This article proposes an improved version of GOES_H2, which has been combined with a radiative transfer parameterization (RTP) and the McClear clear-sky model (MC). This new version, hereafter designated RTP_MC_GOES_H2, was tested on eight stations from the Baseline Surface Radiation Network, located in North and South America, and covered by GOES-13. RTP_MC_GOES_H2 improves the hourly GHI estimates independently of the type of sky. This improvement is independent of the climate, no matter the station, the RTP_MC_GOES_H2 gives better results of MBE and RMSE than the original GOES_H2 method. Indeed, the MBE and RMSE values, respectively, change from −11.93% to −2.42% and 23.24% to 18.24% for North America and from −4.35% to 1.79% and 19.97% to 17.37 for South America. Moreover, the flexibility of the method may allow to improve results in the presence of snow cover and rainy/variable weather. Furthermore, RTP_MC_GOES_H2 results outperform or equalize those of other operational models.


2021 ◽  
Vol 784 ◽  
pp. 1-66
Author(s):  
Amanda Martins Dias ◽  
John Edwin Lattke

The taxonomy of the giant ants of the genus Dinoponera is revised based on female and male morphology. Eight species are recognized. Dinoponera nicinha sp. nov., from Amazonas and Rondônia, Brazil, is described and D. grandis (Guérin-Méneville, 1838) is revived. The species D. australis Emery, 1901 and D. snellingi Lenhart, Dash & Mackay, 2013, plus the subspecies D. australis bucki Borgmeier, 1937 and D. australis nigricolor Borgmeier, 1937 are synonymized under D. grandis sp. rev. An unnamed and unidentified male is reported. In general, male morphology has greater and more discrete variation than in females, but they are scarce in museum collections. Species distributions are updated and illustrated, the genus ranging from southern Colombia to northern Argentina, with no reliable records from the Guiana Shield and all nominal species occurring in Brazil.  Intraspecific variation and natural history are discussed. New illustrated identification keys are provided for both sexes. Future studies should address the collection of fresh specimens for molecular work and to assess the conservation status of several species and populations.


Zootaxa ◽  
2021 ◽  
Vol 5048 (3) ◽  
pp. 435-443
Author(s):  
RACHEL D. GLYNN ◽  
ANDREW EDWARD Z. SHORT

The Neotropical water scavenger beetle genus Chasmogenus Sharp, 1882 is a diverse lineage with 34 described species. Here, three new species from the southwestern margin of the Guiana Shield are described using an integrative approach combining adult morphology and molecular data: Chasmogenus clinatus sp. n. (Brazil: Amazonas, Venezuela: Amazonas), C. gironae sp. n. (Venezuela: Amazonas), and C. inpa sp. n. (Brazil: Amazonas). Examination of the male genitalia is essential for confident identifications and thus unassociated females may prove extremely difficult to identify. New distributional records in Brazil for C. acuminatus Smith & Short, 2020 are provided as well as habitus images of newly described species and an updated key to the species from Venezuela, Suriname, Guyana, French Guiana and northern Brazil.  


Tectonics ◽  
2021 ◽  
Author(s):  
Artiom LOPAREV ◽  
Delphine ROUBY ◽  
Dominique CHARDON ◽  
Massimo DALL’ASTA ◽  
François SAPIN ◽  
...  

Zootaxa ◽  
2021 ◽  
Vol 4981 (3) ◽  
pp. 401-448
Author(s):  
MOISÉS ESCALONA ◽  
ENRIQUE LA MARCA ◽  
MICHELLE CASTELLANOS ◽  
ANTOINE FOUQUET ◽  
ANDREW J. CRAWFORD ◽  
...  

Boana xerophylla is a common treefrog widely distributed in northern Brazil, Colombia, French Guiana, Guyana, Panama, Suriname, Trinidad and Tobago, and Venezuela. A recent study found molecular, acoustic, and morphometric differences between the populations located on opposite sides of the Orinoco River. Here, we carry out an updated molecular phylogenetic analysis, including new samples from all the countries along the distribution area, and analyzed additional call recordings from Brazil, Colombia, French Guiana, Panama, Trinidad and Tobago, and Venezuela. Our phylogenetic inference reveals three geographically restricted lineages: one in the eastern Guiana Shield (corresponding to B. xerophylla sensu stricto), another in the western Guiana Shield, and a third one north of the Orinoco River. Morphological and acoustic data agree with the differentiation between the populations north of the Orinoco River and the eastern Guiana Shield despite the low genetic p-distances observed (16S rRNA: 0.7–2.2 %). We argue that the populations north of the Orinoco River correspond to a new species, sister of B. xerophylla. We name and describe Boana platanera sp. nov. from the southern versant of the Cordillera de Mérida (08º48’26’’ N, 70º30’46’’ W, WGS 84; 947 m asl), Venezuela, and refer all the populations north of the Orinoco River currently identified as B. xerophylla to this species. The new species can be readily diagnosed from B. xerophylla (characters of the latter in parentheses) by a pale orange-yellow or light brown dorsal coloration (dark brown to green), palpebral membrane with dark pigments (pigments absent); pericloacal region dark brown (cream), advertisement call with shorter first note length than B. xerophylla. This study represents an empirical example regarding false negatives behind genetic thresholds for species discovery, appraising the use of integrative taxonomic approaches. 


Author(s):  
Loïc Epelboin ◽  
Carole Eldin ◽  
Pauline Thill ◽  
Vincent Pommier de Santi ◽  
Philippe Abboud ◽  
...  

Abstract Purpose of Review In this review, we report on the state of knowledge about human Q fever in Brazil and on the Guiana Shield, an Amazonian region located in northeastern South America. There is a contrast between French Guiana, where the incidence of this disease is the highest in the world, and other countries where this disease is practically non-existent. Recent Findings Recent findings are essentially in French Guiana where a unique strain MST17 has been identified; it is probably more virulent than those usually found with a particularly marked pulmonary tropism, a mysterious animal reservoir, a geographical distribution that raises questions. Summary Q fever is a bacterial zoonosis due to Coxiella burnetii that has been reported worldwide. On the Guiana Shield, a region mostly covered by Amazonian forest, which encompasses the Venezuelan State of Bolivar, Guyana, Suriname, French Guiana, and the Brazilian State of Amapá, the situation is very heterogeneous. While French Guiana is the region reporting the highest incidence of this disease in the world, with a single infecting clone (MST 117) and a unique epidemiological cycle, it has hardly ever been reported in other countries in the region. This absence of cases raises many questions and is probably due to massive under-diagnosis. Studies should estimate comprehensively the true burden of this disease in the region.


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