scholarly journals Community reorganization in forest understories buried by volcanic tephra

Ecosphere ◽  
2017 ◽  
Vol 8 (12) ◽  
pp. e02045 ◽  
Author(s):  
Donald B. Zobel ◽  
Joseph A. Antos
Keyword(s):  
Ecology ◽  
1992 ◽  
Vol 73 (2) ◽  
pp. 698-701 ◽  
Author(s):  
Donald B. Zobel ◽  
Joseph A. Antos

2016 ◽  
Vol 11 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Satoru Oishi ◽  
◽  
Masahiro Iida ◽  
Masahide Muranishi ◽  
Mariko Ogawa ◽  
...  
Keyword(s):  
X Band ◽  

The present study shows the possibility of using X-band multi-parameter radar to detect volcanic tephra for estimating the amount of volcanic tephra in the air even when the amount of volcanic tephra is very low. The model proposed in this study can detect tephra with diameters of 0.5 mm to 3 mm. Through the observation experiment and the model proposal, the present study shows successful detection of volcanic tephra in the air by using X-band multi-parameter radar.


1982 ◽  
Vol 12 (3) ◽  
pp. 717-719 ◽  
Author(s):  
Donald B. Zobel ◽  
Joseph A. Antos

During the second growing season after the 1980 eruption of Mount St. Helens, AbiesamabilisDougl. ex Forbes, A. procera Rehd., and Pinusmonticola Dougl. ex D. Don produced adventitious roots into tephra, the first known instance of rooting by these species. Abieslasiocarpa (Hook.) Nutt., Chamaecyparisnootkatensis (D. Don) Spach, Thujaplicata Donn. ex D. Don, Tsugaheterophylla (Raf.) Sarg., and T. mertensiana (Bong.) Carr. also adventitiously rooted; Pseudotsugamenziesii (Mirb.) Franco did not.


2004 ◽  
Vol 36 (1) ◽  
pp. 334
Author(s):  
G. Siavalas ◽  
E. Tsompanidou ◽  
S. Kalaitzidis ◽  
A. Bouzinos ◽  
Κ. Christanis

With the present study it is intended to assess the depositional palaeoenvironment of the lower part of the Lignite-bearing Sequence in the Ptolemais Basin, and more specifically in the areas of Notio-Field and Tomeas-6 open pits. The sediments under study represent the seam between the Volcanic Tephra Layer and the Basal Marl, which constitute the roof and the floor, respectively. Coal-petrographic results showed that Huminite is the main macerai group (84-96%), while macérais from Liptinite and Inertinite groups display low values (<10%). In bulk lignite samples the main mineral phases are quartz, calcite, clay minerals and feldspars, while in the ashes the main phases are quartz, anhydrite and lime. The palaeoenvironment of the lignite formation was reconstructed using the lithological, coalpetrographic and mineralogical data, as well as coal-facies diagrammes. In Notio-Field Mine, at the early stages of lignite formation the conditions used to be limnotelmatic, while in Tomeas-6 Mine they were telmatic. Upwards the conditions turned to more telmatic in both mine areas. The vegetation was mainly herbaceous with some arboreal elements occurring mostly in Tomeas-6 area. The water influx was generally intense resulting in enhanced inorganic input


2017 ◽  
Author(s):  
Rebecca Möller ◽  
Marco Möller ◽  
Peter A. Kukla ◽  
Christoph Schneider

Abstract. This Article reports results from a field experiment investigating the influence of volcanic tephra coverage on glacier ablation. These influences are known to be significantly different from those of moraine debris on glaciers due to the contrasting grain size distribution and thermal conductivity. Influences of tephra deposits on glacier ablation have hardly been studied so far. For the experiment, artificial plots of two different tephra types from Eyjafjallajökull and Grimsvötn volcanoes were installed on a snow-covered glacier surface of Vatnajökull ice cap, Iceland.Ablation was automatically monitored along with atmospheric variables and ablation on a non-tephra covered reference site over the summer season 2015. For each of the two volcanic tephra types, three plots (~ 1.5 mm, ~ 8.5 mm and ~ 80 mm) were monitored. After limiting the records to a period of reliable measurements, a 50-days dataset of hourly records was obtained, which can be downloaded from the Pangaea data repository (https://www.pangaea.de; https://doi.org/10.1594/PANGAEA.876656). The experiment shows a substantial increase of ablation under the ~ 1.5 mm and ~ 8.5 mm tephra plots when compared to uncovered conditions. Only under the thick tephra cover some insulating effects could be observed. This result is in contrast to other studies which depicted insulating effects for much thinner tephra coverson bare-ice glacier surfaces. Differences between the influences of the two different petrological types of tephra exist but are small.


2004 ◽  
Vol 24 (1-2) ◽  
pp. 33-40
Author(s):  
Teija Kekonen ◽  
John Moore ◽  
Paavo Perämäki ◽  
Tñnu Martma

1974 ◽  
Vol 78 (1) ◽  
pp. 19 ◽  
Author(s):  
Charles J. Vitaliano ◽  
Dorothy B. Vitaliano
Keyword(s):  

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