Characterization of products of the early stages of pedogenesis in ornithogenic soil from Maritime Antarctica

2015 ◽  
Vol 67 (1) ◽  
pp. 70-78 ◽  
Author(s):  
G. C. Poggere ◽  
V. F. Melo ◽  
M. R. Francelino ◽  
C. E. Schaefer ◽  
F. N. Simas
Solid Earth ◽  
2015 ◽  
Vol 6 (2) ◽  
pp. 583-594 ◽  
Author(s):  
E. L. Poelking ◽  
C. E. R. Schaefer ◽  
E. I. Fernandes Filho ◽  
A. M. de Andrade ◽  
A. A. Spielmann

Abstract. Integrated studies on the interplay between soils, periglacial geomorphology and plant communities are crucial for the understanding of climate change effects on terrestrial ecosystems of maritime Antarctica, one of the most sensitive areas to global warming. Knowledge on physical environmental factors that influence plant communities can greatly benefit studies on the monitoring of climate change in maritime Antarctica, where new ice-free areas are being constantly exposed, allowing plant growth and organic carbon inputs. The relationship between topography, plant communities and soils was investigated on Potter Peninsula, King George Island, maritime Antarctica. We mapped the occurrence and distribution of plant communities and identified soil–landform–vegetation relationships. The vegetation map was obtained by classification of a QuickBird image, coupled with detailed landform and characterization of 18 soil profiles. The sub-formations were identified and classified, and we also determined the total elemental composition of lichens, mosses and grasses. Plant communities on Potter Peninsula occupy 23% of the ice-free area, at different landscape positions, showing decreasing diversity and biomass from the coastal zone to inland areas where sub-desert conditions prevail. There is a clear dependency between landform and vegetated soils. Soils that have greater moisture or are poorly drained, and with acid to neutral pH, are favourable for moss sub-formations. Saline, organic-matter-rich ornithogenic soils of former penguin rookeries have greater biomass and diversity, with mixed associations of mosses and grasses, while stable felsenmeers and flat rocky cryoplanation surfaces are the preferred sites for Usnea and Himantormia lugubris lichens at the highest surface. Lichens sub-formations cover the largest vegetated area, showing varying associations with mosses.


2021 ◽  
Vol 25 (6) ◽  
pp. 87-92
Author(s):  
A. M. Mambetova ◽  
D. V. Bizheva ◽  
I. K. Thabisimova

BACKGROUND. Natriuretic peptides have cardio- and renoprotective effects, inhibiting inflammatory and proliferative processes. The role of natriuretic peptides in the early diagnosis and characterization of chronic kidney disease (CKD) and cardiovascular complications as the disease development and progresses has not been studied.TNEAIM: to study the level of natriuretic peptides in children depending on the stage of CKD development and to assess the significance of this indicator.PATIENTS AND METHODS. The study involved 93 children with congenital diseases of the urinary system at the age from 3 to 18 years. Three groups were identified: group I - 54 patients with CKD stage I , group II - 29 patients with CKD stage II; Group III - 10 children with CKD stages IV-V (patients with CKD stages IV and V were combined due to their small amount). Control group - 10 clinically healthy children of the corresponding age. The N-terminal propeptide of natriuretic hormone (NT-proBNP) was determined in the blood by the enzyme-linked immunosorbent assay.RESULTS. An increase in the level of NT-proBNP by 28.7% takes place already in the early stages of CKD. With the progression of CKD, an increase in the level of NT-proBNP was noted from 57.4 % in children in the group of patients with stage I CKD to 80 % in children in group III patients. The maximum concentrations of NT-proBNP, many times higher than those in CKD stages I and II, were observed in children with CKD stages IV-V. The degree of increase in the level of NT-proBNP correlated with the severity of CKD.CONCLUSION. In the diagnosis and characterization of CKD and cardiorenal syndrome in children, the determination of the level of natriuretic peptides is of great importance. A high level of natriuretic peptides characterizes the presence of cardiorenal relationships and can be used as an additional criterion for assessing the severity of CKD, including at the early stages of its development.


1973 ◽  
Vol 21 (3) ◽  
pp. 709-712 ◽  
Author(s):  
M. Hoshi ◽  
M. Williams ◽  
Y. Kishimoto

2000 ◽  
Vol 123 (2) ◽  
pp. 699-710 ◽  
Author(s):  
Virginie N. Guyon ◽  
James D. Astwood ◽  
Ethan C. Garner ◽  
A. Keith Dunker ◽  
Loverine P. Taylor

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