Vegetation plot and trait data from phonolitic and basaltic rocks on La Palma (Canary Islands, Spain)

Hydrogen (H2) is one of the most abundant trace species in volcano-hydrothermal systems and is a key participant in many redox reactions occurring in the hydrothermal reservoir gas. Although H2 can be produced in soils by N2-fixing and fertilizing bacteria, soils are considered nowadays as sinks of molecular hydrogen (Smith-Downey et al. 2006). Because of its chemical and physical characteristics, H2 generated within the crust moves rapidly and escapes to the atmosphere. These characteristics make H2 one of the best geochemical indicators of magmatic and geothermal activity at depth. Cumbre Vieja volcano (La Palma, Canary Islands) is the most active basaltic volcano in the Canaries with seven historical eruptions being Tenegu&#237;a eruption (1971) the most recent one. Cumbre Vieja volcano is characterized by a main north&#8211;south rift zone 20 km long, up to 1950 m in elevation and covering an area of 220 km2 with vents located at the northwest and northeast. Cumbre Vieja does not show any visible degassing (fumaroles, etc.). For that reason, the geochemical volcano monitoring program at Cumbre Vieja volcano has been focused on soil degassing surveys. &#160;Here we show the results of soil H2 emission surveys that have been carried out regularly since 2001. Soil gas samples were collected in about 600 sampling sites selected to obtain a homogeneous distribution at about 40 cm depth using a metallic probe and 60 cc hypodermic syringes and stored in 10 cc glass vials. H2 content was analysed later by a VARIAN CP4900 micro-GC. A simple diffusive emission mechanism was applied to compute the emission rate of H2 at each survey. Diffuse H2 emission values were used to construct spatial distribution maps by using sequential Gaussian simulation (sGs) algorithm, allowing the estimation of the emission rate from the volcano. Between 2001-2003, the average diffuse H2 emission rate was &#8764;2.5 kg&#183;d&#8722;1 and an increase of this value was observed between 2013-2017 (&#8764;16.6 kg&#183;d&#8722;1), reaching a value of 36 kg&#183;d&#8722;1 on June 2017, 4 month before the first recent seismic swarm in October, 2017 at Cumbre Vieja volcano. Six additional seismic swarms had occurred at Cumbre Vieja volcano (February 2018, July-August 2020; October 8-10, 2020; October 17-19, 2020, November 21, 2020 and December 23-26, 2020) and changes of diffuse H2 emission related to this unrest had been observed reaching values up to &#8764;70 kg&#183;d&#8722;1. Diffuse H2 emission surveys have demonstrated to be sensitive and excellent precursors of magmatic processes occurring at depth in Cumbre Vieja. Periodic diffuse H2 emission surveys provide valuable information to improve and optimize the detection of early warning signals of volcanic unrest at Cumbre Vieja volcano.

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Geochemical and Volcanological Evolution of La Palma, Canary Islands

Journal of Petrology ◽

10.1093/petrology/egx052 ◽

2017 ◽

Vol 58 (6) ◽

pp. 1227-1248 ◽

Cited By ~ 7

Author(s):

Andreas Klügel ◽

Karsten Galipp ◽

Kaj Hoernle ◽

Folkmar Hauff ◽

Simon Groom

Keyword(s):

Canary Islands ◽

La Palma

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Optimization of genetic diagnosis of oculopharyngeal muscular dystrophy and its application in the analysis of a family pedigree from La Palma Island (Canary Islands, Spain)

Medicina Clínica (English Edition) ◽

10.1016/j.medcle.2017.07.003 ◽

2017 ◽

Vol 149 (4) ◽

pp. 177-178

Author(s):

Nuba Zamora-Jordán ◽

Mariano Hernández ◽

José A. Pérez

Keyword(s):

Muscular Dystrophy ◽

Canary Islands ◽

Genetic Diagnosis ◽

Oculopharyngeal Muscular Dystrophy ◽

La Palma ◽

Family Pedigree

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523676 (2013 UL10): the first active red centaur

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731224 ◽

2018 ◽

Vol 620 ◽

pp. A93 ◽

Cited By ~ 1

Author(s):

E. Mazzotta Epifani ◽

E. Dotto ◽

S. Ieva ◽

D. Perna ◽

P. Palumbo ◽

...

Keyword(s):

Production Rate ◽

Canary Islands ◽

Colour Index ◽

Nucleus Size ◽

Dust Production ◽

La Palma ◽

Upper Limit ◽

Nucleus Surface ◽

Perihelion Passage

Aims. We present observations of 523676 (2013 UL10), a centaur orbiting between Jupiter and Uranus that is dynamically similar to the few tens of active centaurs that are currently known. Methods. We analysed visible BVR images of the centaur obtained at the Telescopio Nazionale Galileo (La Palma, Canary Islands, Spain) to investigate the weak comet-like activity and to derive information on the nucleus surface colours and size. Results. Centaur 523676 (2013 UL10) is the only centaur known so far that has both comet-like activity and red surface colours: its nucleus has a colour index [B – R] = 1.88 ± 0.11. The nucleus R magnitude (R = 20.93 ± 0.09) allowed us to derive an upper limit for its nucleus size of D ≤ 10 km. We estimated its dust production rate to be Qd ~ 10 kg s−1 at 6.2 au (just after its perihelion passage), resulting in a timescale for the surface blanketing process τB of approximately tens of years, which is very short with respect to typical dynamical lifetime inside the group. Future monitoring of 523676 (2013 UL10) is needed to further constrain the blanketing model for active centaurs and its timescale.

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Halimeda incrassata (Bryopsidales, Chlorophyta) reaches the Canary Islands: mid- and deep-water meadows in the eastern subtropical Atlantic Ocean

Botanica Marina ◽

10.1515/bot-2017-0104 ◽

2018 ◽

Vol 61 (2) ◽

pp. 103-110 ◽

Cited By ~ 3

Author(s):

Carlos Sangil ◽

Laura Martín-García ◽

Julio Afonso-Carrillo ◽

Jacinto Barquín ◽

Marta Sansón

Keyword(s):

Atlantic Ocean ◽

Canary Islands ◽

Deep Water ◽

Population Coverage ◽

Isolated Populations ◽

La Palma ◽

Soft Bottoms ◽

The Caribbean ◽

Marine Flora ◽

First Time

AbstractExtensive offshore meadows ofHalimeda incrassataare documented for the first time in sandy bottoms of La Palma, Canary Islands.Halimeda incrassataforms dense sublittoral assemblages between 20 and 55 m, but isolated populations occur down to 65 m depth. This species currently spreads over an area of 9.14 ha. Population coverage varies with depth, with the highest values at 35–40 m and an average cover of 62.34%. The calcified segments ofH. incrassataact as a stable substratum in these soft bottoms for the growth of other macroalgae, such as the rhodophytesLophocladia trichocladosandCottoniella filamentosa. Specimens reach lengths of up to 10 cm, shorter than individuals from the Caribbean. Although it is difficult to ascertain whether this species is a recent introduction, there is evidence of a correlation between the increase in population coverage and recent ocean warming, constituting another example of the tropicalization of the marine flora of this region.

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