scholarly journals Extreme pointer years in tree-ring records of Central Spain as evidence of climatic events and the eruption of the Huaynaputina Volcano (Peru, 1600 AD)

2012 ◽  
Vol 8 (2) ◽  
pp. 751-764 ◽  
Author(s):  
M. Génova
Keyword(s):  
Tree Ring ◽  
Summer Precipitation ◽  
Limiting Factor ◽  
Special Significance ◽  
Central Spain ◽  
Complementary Information ◽  
Annual Increase ◽  
Pointer Years ◽  
First Time ◽  
Minimum Index

Abstract. The study of pointer years of numerous tree-ring chronologies of the central Iberian Peninsula (Sierra de Guadarrama) could provide complementary information about climate variability over the last 405 yr. In total, 64 pointer years have been identified: 30 negative (representing minimum growths) and 34 positive (representing maximum growths), the most significant of these being 1601, 1963 and 1996 for the negative ones, and 1734 and 1737 for the positive ones. Given that summer precipitation was found to be the most limiting factor for the growth of Pinus in the Sierra de Guadarrama in the second half of the 20th century, it is also an explanatory factor in almost 50% of the extreme growths. Furthermore, these pointer years and intervals are not evenly distributed throughout time. Both in the first half of the 17th and in the second half of 20th, they were more frequent and more extreme and these periods are the most notable for the frequency of negative pointer years in Central Spain. The interval 1600–1602 is of special significance, being one of the most unfavourable for tree growth in the centre of Spain, with 1601 representing the minimum index in the regional chronology. We infer that this special minimum annual increase was the effect of the eruption of Huaynaputina, which occurred in Peru at the beginning of 1600 AD. This is the first time that the effects of this eruption in the tree-ring records of Southern Europe have been demonstrated.

scholarly journals Extreme pointer years in tree-ring records of Central Spain as evidence of volcanic eruptions (Huaynaputina, Peru, 1600 AC) and other climatic events

2011 ◽  
Vol 7 (6) ◽  
pp. 4223-4259 ◽  
Author(s):  
M. Génova
Keyword(s):  
20Th Century ◽  
Tree Ring ◽  
Summer Precipitation ◽  
Volcanic Eruptions ◽  
Special Significance ◽  
Central Spain ◽  
Complementary Information ◽  
Pointer Years ◽  
First Time ◽  
Minimum Index

Abstract. The study of pointer years based on the numerous tree-ring chronologies of the central Iberian Peninsula (Sierra de Guadarrama) could provide complementary information about climate variability over the last 405 years. In total, 64 pointer years have been identified: 30 negative (representing minimum growths) and 34 positive (representing maximum growths), the most significant of these being 1601, 1963 and 1996 for the negative ones, and 1734 and 1737 for the positive ones. Given that summer precipitation has been the most incident factor in the general variability of growth of Pinus in the Sierra de Guadarrama in the second half of the 20th century, it is also an explanatory factor in almost 50% of the extreme growths. Furthermore, the data show that there has been variability over the centuries in the distribution of the frequencies of pointer years and intervals. The first half of the 17th century, together with the second half of the 20th century, constitute the two most notable periods for the frequency of negative pointer years in Central Spain. This variability was sufficiently notable to affirm that, both in the 17th and 20th centuries, the macroclimatic anomalies that affected growth were more frequent and more extreme than in the other two centuries analysed. The period 1600–1602 is of special significance, being one of the most unfavourable for tree growth in the centre of Spain, with 1601 representing the minimum index in the regional chronology. It is possible to infer that these phenomena are the effect of the eruption of Huaynaputina, which occurred in Peru at the beginning of 1600 AD. This is the first time that the effects of this eruption in the tree-ring records of central and southern Europe have been demonstrated.

scholarly journals Comparative investigation of lasing and amplification performance in cryogenic Yb:YLF systems

2021 ◽  
Vol 127 (3) ◽  
Author(s):  
Umit Demirbas ◽  
Martin Kellert ◽  
Jelto Thesinga ◽  
Yi Hua ◽  
Simon Reuter ◽  
...  
Keyword(s):  
Continuous Wave ◽  
Estimation Method ◽  
Laser Cavity ◽  
Comparative Investigation ◽  
Limiting Factor ◽  
Experimental Conditions ◽  
Temperature Estimation ◽  
Transverse Temperature ◽  
First Time

AbstractWe present detailed experimental results with cryogenic Yb:YLF gain media in rod-geometry. We have comparatively investigated continuous-wave (cw) lasing and regenerative amplification performance under different experimental conditions. In the cw lasing experiments effect of crystal doping, cw laser cavity geometry and pump wavelength on lasing performance were explored. Regenerative amplification behavior was analyzed and the role of depolarization losses on performance was investigated. A recently developed temperature estimation method was also employed for the first time in estimating average crystal temperature under lasing conditions. It is shown that the thermal lens induced by transverse temperature gradients is the main limiting factor and strategies for future improvements are discussed. To the best of our knowledge, the achieved results in this study (375 W in cw, and 90 W in regenerative amplification) are the highest average powers ever obtained from this system via employing the broadband E//a axis.

Is temperature still the most limiting factor for growth in northern boreal forests?

The Holocene ◽  
2021 ◽  
pp. 095968362110116
Author(s):  
Jeroen DM Schreel
Keyword(s):  
Tree Ring ◽  
Boreal Forests ◽  
Ring Width ◽  
Temperature Fluctuations ◽  
Limiting Factor ◽  
Tree Ring Width ◽  
Climate Reconstructions ◽  
Latewood Density

Over the last few decades – at a range of northern sites – changes in tree-ring width and latewood density have not followed mean summertime temperature fluctuations. This discrepancy sharply contrasts an earlier correlation between those variables. As the origin of this inconsistency has not been fully deciphered, questions have emerged regarding the use of tree-ring width and latewood density as a proxy in dendrochronological climate reconstructions. I suggest that temperature is no longer the most limiting factor in certain boreal areas, which might explain the observed divergence.

scholarly journals An 854-Year Tree-Ring Chronology of Scots Pine for South-West Finland

2014 ◽  
Vol 31 (1) ◽  
pp. 61-68 ◽  
Author(s):  
Samuli Helama ◽  
Jari Holopainen ◽  
Mauri Timonen ◽  
Kari Mielikäinen
Keyword(s):  
Tree Ring ◽  
Ring Width ◽  
Summer Precipitation ◽  
Total Sample ◽  
Early Summer ◽  
The South ◽  
Tree Ring Chronology ◽  
The North ◽  
South West ◽  
The North Atlantic Oscillation

Abstract A near-millennial tree-ring chronology (AD 1147-2000) is presented for south-west Finland and analyzed using dendroclimatic methods. This is a composite chronology comprising samples both from standing pine trees (Pinus sylvestris L.) and subfossil trunks as recovered from the lake sediments, with a total sample size of 189 tree-ring sample series. The series were dendrochronologically cross-dated to exact calendar years to portray variability in tree-ring widths on inter-annual and longer scales. Al though the studied chronology correlates statistically significantly with other long tree-ring width chronologies from Finland over their common period (AD 1520-1993), the south-west chronology did not exhibit similarly strong mid-summer temperature or spring/early-summer precipitation signals in comparison to published chronologies. On the other hand, the south-west chronology showed highest correlations to the North Atlantic Oscillation indices in winter/spring months, this association following a dendroclimatic feature common to pine chronologies over the region and adjacent areas. Paleoclimatic comparison showed that tree-rings had varied similarly to central European spring temperatures. It is postulated that the collected and dated tree-ring material could be studied for wood surface reflectance (blue channel light intensity) and stable isotopes, which both have recently shown to correlate notably well with summer temperatures.

scholarly journals Is Young Age a Limiting Factor When Training Balance? Effects of Child-Oriented Balance Training in Children and Adolescents

2018 ◽  
Vol 30 (1) ◽  
pp. 176-184 ◽  
Author(s):  
Michael Wälchli ◽  
Jan Ruffieux, ◽  
Audrey Mouthon ◽  
Martin Keller ◽  
Wolfgang Taube
Keyword(s):  
Postural Control ◽  
Postural Sway ◽  
Age Groups ◽  
Balance Training ◽  
Young Age ◽  
Limiting Factor ◽  
Training Outcomes ◽  
Balance Exercises ◽  
Explosive Force ◽  
First Time

Purpose: Balance training (BT) studies in children reported conflicting results without evidence for improvements in children under the age of 8. The aim of this study therefore was to compare BT adaptations in children of different age groups to clarify whether young age prevents positive training outcomes. Methods: The effects of 5 weeks of child-oriented BT were tested in 77 (38 girls and 39 boys) participants of different age groups (6–7 y, 11–12 y, and 14–15 y) and compared with age-matched controls. Static and dynamic postural control, explosive strength, and jump height were assessed. Results: Across age groups, dynamic postural sway decreased (−18.7%; P = .012; ) and explosive force increased (8.6%; P = .040; ) in the intervention groups. Age-specific improvements were observed in dynamic postural sway, with greatest effects in the youngest group (−28.8%; P = .026; r = .61). Conclusion: In contrast to previous research using adult-oriented balance exercises, this study demonstrated for the first time that postural control can be trained from as early as the age of 6 years in children when using child-oriented BT. Therefore, the conception of the training seems to be essential in improving balance skills in young children.

scholarly journals The influence of climatic conditions on the tree-ring width of wild service trees (Sorbus torminalis L.) in Wielkopolska

2016 ◽  
Vol 77 (2) ◽  
pp. 117-123 ◽  
Author(s):  
Anna Cedro
Keyword(s):  
Tree Ring ◽  
Negative Impact ◽  
Positive Impact ◽  
Ring Width ◽  
Climatic Conditions ◽  
Climatic Data ◽  
Pointer Years ◽  
The North ◽  
Sorbus Torminalis ◽  
Temperature And Precipitation

AbstractThe wild service tree (Sorbus torminalis L.) is a very rare tree species in Poland, where it reaches the north-eastern border of its natural range. The majority of this species’ stands is found in Wielkopolska. This study was aimed at examining the relationships between the growth and climate for trees of the species Sorbus torminalis L. growing in the Wielkopolska National Park and the Pniewy forest district (Wielkopolska). The samples for the analysis were taken from 63 trees. However, taking into account the missing growth rings and the difficult identification of the tree ring borders in sapwood, only ca. 30% of the samples could be synchronised and dated accurately. Applying the classic methods of dendrochronological dating, a 94- year STW chronology was constructed, spanning the years of 1920-2013. The chronology, in turn, was used as a basis for dendroclimatological analyses, including correlation, response function, and pointer years. The climatic data used in the analyses came from the meteorological station in Poznań; providing air temperature and precipitation for a period of 66 years (1948-2013) and 48 years of insolation data (1966-2013). Insolation had the highest negative impact and precipitation had the highest positive impact on the annual growth in May and June. Positive pointer years could be linked to humid months with low insolation during the growing season, while negative pointer years are characterised by deficient precipitation, a large number of sunny hours, and high air temperatures in the summer months.

scholarly journals Root Proteomic Analysis of Two Grapevine Rootstock Genotypes Showing Different Susceptibility to Salt Stress

2020 ◽  
Vol 21 (3) ◽  
pp. 1076 ◽  
Author(s):  
Bhakti Prinsi ◽  
Osvaldo Failla ◽  
Attilio Scienza ◽  
Luca Espen
Keyword(s):  
Salt Stress ◽  
Abiotic Stress ◽  
Energy Metabolism ◽  
Agricultural Soils ◽  
Agricultural Practices ◽  
Limiting Factor ◽  
Protective Mechanisms ◽  
Biochemical Level ◽  
The Impact ◽  
First Time

Salinity represents a very limiting factor that affects the fertility of agricultural soils. Although grapevine is moderately susceptible to salinity, both natural causes and agricultural practices could worsen the impact of this abiotic stress. A promising possibility to reduce this problem in vineyards is the use of appropriate graft combinations. The responses of grapevine rootstocks to this abiotic stress at the root level still remain poorly investigated. In order to obtain further information on the multifaceted responses induced by salt stress at the biochemical level, in the present work we analyzed the changes that occurred under control and salt conditions in the root proteomes of two grapevine rootstock genotypes, M4 and 101.14. Moreover, we compared the results considering that M4 and 101.14 were previously described to have lower and higher susceptibility to salt stress, respectively. This study highlighted the greater capability of M4 to maintain and adapt energy metabolism (i.e., synthesis of ATP and NAD(P)H) and to sustain the activation of salt-protective mechanisms (i.e., Na sequestration into the vacuole and synthesis of osmoprotectant compounds). Comparitively, in 101.14 the energy metabolism was deeply affected and there was an evident induction of the enzymatic antioxidant system that occurred, pointing to a metabolic scenario typical of a suffering tissue. Overall, this study describes for the first time in grapevine roots some of the more crucial events that characterize positive (M4) or negative (101.14) responses evoked by salt stress conditions.

scholarly journals Tree-Ring Width and Carbon Isotope Chronologies Track Temperature, Humidity, and Baseflow in the Tianshan Mountains, Central Asia

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1308
Author(s):  
Yuting Fan ◽  
Huaming Shang ◽  
Ye Wu ◽  
Qian Li
Keyword(s):  
Stable Isotopes ◽  
Tree Ring ◽  
Ring Width ◽  
River Basins ◽  
Tianshan Mountains ◽  
Limiting Factor ◽  
Source Water ◽  
Tree Ring Width ◽  
The North ◽  
Temperature And Precipitation

Concerns have been raised about the negative impacts of global warming on the hydrological climate change and ecosystems of Asia. Research on the high-altitude mountainous regions of Asia with relatively short meteorological and hydrological records relies on paleoclimate proxy data with long time scales. The stable isotopes of tree-rings are insightful agents that provide information on pre-instrumental climatic and hydrological fluctuations, yet the variability of these data from different regions along the Tianshan Mountains has not been fully explored. Herein, we related climate data with tree-ring width (TRW) chronologies and δ13C (stable carbon isotope discrimination) series to discern if the Picea schrenkiana in the Ili and Manas River Basins are sensitive to climatic factors and baseflow (BF). The results show significant correlations between temperature and TRW chronologies, temperature and δ13C, relative humidity and TRW chronologies, and BF and δ13C. Temperature, particularly the mean late summer to early winter temperature, is a pronounced limiting factor for the tree-ring and the δ13C series in the Manas River Basin, located in the middle of the North Tianshan Mountains. Meanwhile, mean early spring to early autumn temperature is a limiting factor for that of the Ili River Basin, located on the southern slope of the North Tianshan Mountains. We conclude that different seasonal variations in temperature and precipitation of the two river basins exerted significant control on tree growth dynamics. Tree-ring width and tree-ring δ13C differ in their sensitivity to climate and hydrological parameters to which tree-ring δ13C is more sensitive. δ13C showed significant lag with precipitation, and the lag correlation showed that BF, temperature, and precipitation were the most affected factors that are often associated with source water environments. δ13C series correlated positively to winter precipitation, suggesting baseflow was controlling the length of the growing season. The tree-ring δ13C provided information that coincided with TRW chronologies, and supplied some indications that were different from TRW chronologies. The carbon stable isotopes of tree-rings have proven to be powerful evidence of climatic signals and source water variations.

scholarly journals Climate signals in a multispecies tree-ring network from central and southern Italy and reconstruction of the late summer temperatures since the early 1700s

2017 ◽  
Vol 13 (11) ◽  
pp. 1451-1471 ◽  
Author(s):  
Giovanni Leonelli ◽  
Anna Coppola ◽  
Maria Cristina Salvatore ◽  
Carlo Baroni ◽  
Giovanna Battipaglia ◽  
...  
Keyword(s):  
Tree Ring ◽  
Summer Precipitation ◽  
Late Summer ◽  
Summer Drought ◽  
Stable Model ◽  
Italian Peninsula ◽  
Reconstructed Temperature ◽  
Instrumental Record ◽  
Summer Temperatures ◽  
Climate Signals

Abstract. A first assessment of the main climatic drivers that modulate the tree-ring width (RW) and maximum latewood density (MXD) along the Italian Peninsula and northeastern Sicily was performed using 27 forest sites, which include conifers (RW and MXD) and broadleaves (only RW). Tree-ring data were compared using the correlation analysis of the monthly and seasonal variables of temperature, precipitation and standardized precipitation index (SPI, used to characterize meteorological droughts) against each species-specific site chronology and against the highly sensitive to climate (HSTC) chronologies (based on selected indexed individual series). We find that climate signals in conifer MXD are stronger and more stable over time than those in conifer and broadleaf RW. In particular, conifer MXD variability is directly influenced by the late summer (August, September) temperature and is inversely influenced by the summer precipitation and droughts (SPI at a timescale of 3 months). The MXD sensitivity to August–September (AS) temperature and to summer drought is mainly driven by the latitudinal gradient of summer precipitation amounts, with sites in the northern Apennines showing stronger climate signals than sites in the south. Conifer RW is influenced by the temperature and drought of the previous summer, whereas broadleaf RW is more influenced by summer precipitation and drought of the current growing season. The reconstruction of the late summer temperatures for the Italian Peninsula for the past 300 years, based on the HSTC chronology of conifer MXD, shows a stable model performance that underlines periods of climatic cooling (and likely also wetter conditions) in 1699, 1740, 1814, 1914 and 1938, and follows well the variability of the instrumental record and of other tree-ring-based reconstructions in the region. Considering a 20-year low-pass-filtered series, the reconstructed temperature record consistently deviates < 1 °C from the instrumental record. This divergence may also be due to the precipitation patterns and drought stresses that influence the tree-ring MXD at our study sites. The reconstructed late summer temperature variability is also linked to summer drought conditions and it is valid for the west–east oriented region including Sardinia, Sicily, the Italian Peninsula and the western Balkan area along the Adriatic coast.

Etude complémentaire de manuscrits des transcriptions et des enregistrements sonores algériens de Béla Bartók

2012 ◽  
Vol 53 (1-3) ◽  
pp. 323-340
Author(s):  
Mehdi Trabelsi
Keyword(s):  
Folk Music ◽  
Source Material ◽  
Bela Bartok ◽  
Special Significance ◽  
Sound Recordings ◽  
Cd Rom ◽  
The Subject ◽  
New Research ◽  
First Time

When travelling in and around Biskra, Algeria, in 1913, Béla Bartók recorded almost two hundred melodies on phonograph cylinders. Bartók’s unique research was the subject of my PhD dissertation at the Sorbonne in Paris in 2003. The dissertation was based on about half of Bartók’s Arab collection available at the time at the Budapest Bartók Archives. In the meantime in 2006, the CD-ROM Bartók and Arab Folk Music has made for the first time available all the surviving transcriptions and sound recordings, which represent Bartók’s collection almost in its entirety. The article summarizes new research into the source material which has recently become available and points out the special significance of his study of Arab folk music for ethnomusicological research into the Maghreb.

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