Zeitschriften und Ausgaben

Volumen 49 (2022): Heft 1 (January 2022)

Volumen 48 (2021): Heft 1 (January 2021)

Volumen 47 (2020): Heft 1 (January 2020)

Volumen 46 (2019): Heft 1 (January 2019)

Volumen 45 (2018): Heft 1 (January 2018)

Volumen 44 (2017): Heft 1 (January 2017)

Volumen 43 (2016): Heft 1 (February 2016)

Volumen 42 (2015): Heft 1 (January 2015)

Volumen 41 (2014): Heft 4 (December 2014)

Volumen 41 (2014): Heft 3 (September 2014)

Volumen 41 (2014): Heft 2 (June 2014)

Volumen 41 (2014): Heft 1 (March 2014)

Volumen 40 (2013): Heft 4 (December 2013)
Special Heft Title: Proceedings of the 3rd Asia Pacific Conference on Luminescence and Electron Spin Resonance Dating Okayama, Japan, 2012

Volumen 40 (2013): Heft 3 (September 2013)

Volumen 40 (2013): Heft 2 (June 2013)

Volumen 40 (2013): Heft 1 (March 2013)

Volumen 39 (2012): Heft 4 (December 2012)

Volumen 39 (2012): Heft 3 (September 2012)

Volumen 39 (2012): Heft 2 (June 2012)

Volumen 39 (2012): Heft 1 (March 2012)

Volumen 38 (2011): Heft 4 (December 2011)

Volumen 38 (2011): Heft 3 (September 2011)
Special Heft Title: Proceedings of the 2nd Asia Pacific Conference on Luminescence Dating, Ahmedabad, India, 2009. Part II Heft Editors: Andrzej Bluszcz, Silesian University of Technology, Gliwice, Poland. Andrzej.Bluszcz@polsl.pl Sheng-Hua Li, The University of Hong Kong, Hong Kong, China. shli@hku.hk Ashok Kumar Singhvi, Physical Research Laboratory, Ahmedabad, India. singhvi@prl.res.in

Volumen 38 (2011): Heft 2 (June 2011)

Volumen 38 (2011): Heft 1 (March 2011)

Volumen 37 (2010): Heft -1 (December 2010)
Proceedings of the 2 Asia Pacific Conference on Luminescence Dating, Ahmedabad, India, 2009. Part I Editors Andrzej Bluszcz, Sheng-Hua Li and Ashok Kumar Singhvi

Volumen 36 (2010): Heft -1 (August 2010)

Volumen 35 (2010): Heft -1 (April 2010)

Volumen 34 (2009): Heft -1 (December 2009)

Volumen 33 (2009): Heft -1 (June 2009)

Volumen 32 (2008): Heft -1 (December 2008)

Volumen 31 (2008): Heft -1 (August 2008)

Volumen 30 (2008): Heft -1 (April 2008)

Volumen 29 (2007): Heft -1 (December 2007)

Volumen 28 (2007): Heft -1 (September 2007)

Volumen 27 (2007): Heft -1 (June 2007)

Volumen 26 (2007): Heft -1 (March 2007)

Zeitschriftendaten
Format
Zeitschrift
eISSN
1897-1695
Erstveröffentlichung
04 Jul 2007
Erscheinungsweise
1 Hefte pro Jahr
Sprachen
Englisch

Suche

Volumen 41 (2014): Heft 4 (December 2014)

Zeitschriftendaten
Format
Zeitschrift
eISSN
1897-1695
Erstveröffentlichung
04 Jul 2007
Erscheinungsweise
1 Hefte pro Jahr
Sprachen
Englisch

Suche

11 Artikel
Uneingeschränkter Zugang

LA-ICP-MS U-Pb dating and REE patterns of apatite from the Tatra Mountains, Poland as a monitor of the regional tectonomagmatic activity

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 306 - 314

Zusammenfassung

Abstract

This study presents apatite LA-ICP-MS U-Pb age and trace elements concentrations data from different granite types from the Tatra Mountains, Poland. Apatite from monazite and xenotime-bearing High Tatra granite was dated at 339 ± 5 Ma. The apatite LREE patterns reflect two types of magmas that contributed to this layered magma series. Apatite from a hybrid allanite-bearing diorite from the Goryczkowa Unit was dated at 340 ± 4 Ma with apatite LREE depletion reflecting the role of allanite and titanite during apatite crystallization. Apatite crystals from a hybrid cumulative rock from the Western Tatra Mountains were dated at 344 ± 3 Ma. Apatite is one of the main REE carriers in this sample and exhibit flat REE patterns.

Taking into account the relatively low closure temperature of the U-Pb system in apatite (350–550°C), the c. 340 Ma apatite ages mark the end of high temperature tectonometamorphic activity in the Tatra Mountains.

Schlüsselwörter

  • apatite
  • U-Pb age
  • REE patterns
  • Tatra Mountains
Uneingeschränkter Zugang

The D e (T, t) plot: A straightforward self-diagnose tool for post-IR IRSL dating procedures

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 315 - 326

Zusammenfassung

Abstract

This study presents a new self-diagnose method for the recently developed post-IR infrared stimulated luminescence (pIRIR) dating protocols. This criterion studies the dependence of equivalent dose (D e) on measurement-temperature (T) and time (t), by applying the D e (t) analysis to the IRLS and pIRIR signals measured under different temperatures, and combines these D e (t) plots into one, so-called the D e (T, t) plot. The pattern of the D e (T, t) plot is shown to be affected by anomalous fading, partial bleaching and non-bleachable signal. A D e plateau can be achieved in the D e (T, t) plot only when the effects of these factors are insignificant. Therefore, this plot can be used as a self-diagnose tool for the validity of pIRIR results. The D e (T, t) analysis has been applied to four recently developed pIRIR protocols, using aeolian samples with different ages. The results show that this self-diagnose tool can be applied to different pIRIR protocols for validating the pIRIR dating results and evaluating the pIRIR measurement conditions.

Schlüsselwörter

  • post-IR IRSL
  • measurement temperature and time
  • De plateau
  • self-diagnose criterion
Uneingeschränkter Zugang

Performance tests using the Lexsyg luminescence reader

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 327 - 333

Zusammenfassung

Abstract

This study presents test measurements on a Lexsyg luminescence reader, acquired by the Giessen luminescence group. The reader is of the type Standard, hence designed for routine determination of palaeodoses using quartz or K-feldspars. The tests include measurements of the stimulation powers, preheat temperatures, OSL- and TL-curves, as well as dose recovery tests and calibration measurements using highly sensitised calibration quartz. A comparison of D e values determined using a Lexsyg reader with single grain D e-values, which have been previously obtained on a Risø reader, is also presented. The results imply that the Lexsyg reader is a highly reliable measurement device with high reproducibility, yielding instrumental uncertainties of around 0.3%.

Schlüsselwörter

  • dosimetry
  • instrumentation
  • reproducibility
  • luminescence dating
Uneingeschränkter Zugang

Estimating the number of components in an OSL decay curve using the Bayesian Information Criterion

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 334 - 341

Zusammenfassung

Abstract

The optically stimulated luminescence (OSL) decay curve is assumed to consist of a number of first-order exponential components. Improper estimation of the number of components leads to under-or over-fitting of the curve under consideration. Hence, correct estimation of the number of components is important to accurately analyze an OSL decay curve. In this study, we investigated the possibility of using the Bayesian Information Criterion to estimate the optimal number of components in an OSL decay curve. We tested the reliability of this method using several hundred measured decay curves and three simulation scenarios. Our results demonstrate that the quality of the identification can be influenced by several factors: the measurement time and the number of channels; the variability of the decay constants; and the signal-to-noise ratios of a decaying component. The results also suggest that the Bayesian Information Criterion has great potential to estimate the number of components in an OSL decay curve with a moderate to high signal-to-noise ratio.

Schlüsselwörter

  • OSL decay curves
  • number of components
  • Bayesian Information Criterion
Uneingeschränkter Zugang

Comparing different post-IR IRSL approaches for the dating of Holocene coastal foredunes from Ruhnu Island, Estonia

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 342 - 351

Zusammenfassung

Abstract

Different post-IR Infrared Stimulated Luminescence (IRSL) approaches are applied to sediments from a Holocene coastal foredune sequence on Ruhnu Island in the eastern Baltic Sea. The comparison of D e-values and ages determined by the different approaches is complimented by fading and bleaching experiments. The fading experiments imply strong fading of IRSL (50°C) signals and no fading of any of the post-IR IRSL signals, but this is not confirmed by the determined D e-values. In fact, post-IR IRSL (150°C) D e-values agree within errors with those calculated for IRSL (50°C). From the bleaching experiments it is inferred that the higher values observed for post-IR IRSL at more elevated stimulation temperatures (225°C/290°C) are likely related to either thermal transfer and/or slow-to-bleach components within the signal. For the dating of the Holocene foredune sequence of Ruhnu Island, the post-IR IRSL (150°C) approach is preferred and these agree with the limited independent age control available from radiocarbon dating. Accordingly, the sequence formed between ca. 7.0 ka and 2.5 ka ago.

Schlüsselwörter

  • luminescence
  • post-IR IRSL
  • foredunes
  • Holocene
  • Baltic Sea
Uneingeschränkter Zugang

Luminescence dating of bricks from the gothic Saint James Church in Toruń

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 352 - 360

Zusammenfassung

Abstract

Saint James Church in Toruń is one of the most important gothic monuments in Poland. The date of the beginning of its construction is known from historical reports but the earlier history of the site remains undiscovered. During the archaeological excavations in years 2010 and 2011 five brick samples were collected for luminescence dating as well as four additional samples from the brick surroundings for the dose rate estimation. The equivalent dose was determined by TL and OSL methods. The TL results differ significantly from the OSL results but the last ones are verified by historical knowledge and radiocarbon dating. Establishing the dose rate from gamma rays needs a special attention because of the complex course of the foundations of the church. The details of the applied approach are presented in the current work. The results obtained indicate that a solid brick construction existed at the site of the presbytery of the Saint James Church before it was build.

Schlüsselwörter

  • dating bricks
  • optically stimulated luminescence
  • thermoluminescence
  • annual dose
Uneingeschränkter Zugang

Optical dating and sedimentary record from the terrace depositional profile of the Warta River (Central Poland)

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 361 - 368

Zusammenfassung

Abstract

Results of OSL dating and sedimentary studies from the profile of the low alluvial terrace of the middle Warta River are presented. The samples were dated using the single-aliquot regenera-tive method. Dating was used to establish a timing of the Weichselian Late Glacial events in the river valley environment. Stable conditions on the floodplain are expressed by the deposition of organic-rich series radiocarbon dated at 12 900-12 600 cal BP and 11 600-10 770 cal BP. Samples for OSL dating were collected from the mineral material deposited during the intensification of flood events during the Weichselian decline. The results obtained for the alluvia range from 12.78 ± 0.62 ka b2k to 14.33 ± 0.74 ka b2k. Sedimentological criteria allowed to distinguish between particular flood events. Overestimation of OSL ages is probably a result of rapidity of environmental changes in that time.

Schlüsselwörter

  • palaeofloods
  • Younger Dryas
  • OSL
  • sedimentological studies
Uneingeschränkter Zugang

Sediment geochronology and spatio-temporal and vertical distributions of radionuclides in the Upper Bonny Estuary (South Nigeria)

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 369 - 376

Zusammenfassung

Abstract

Surface deposits and sediment cores were collected from the Upper Bonny Estuary, located in Southwest Nigeria, and analyzed to determine spatio-temporal and vertical distributions of radio-nuclide activities expressed in Bq·kg−1 dry weight. The results of activities of naturally occurring radionuclides of 226Ra (15 ± 2–34 ± 3 Bq·kg−1), 228Ra (32 ± 5–48 ± 6 Bq·kg−1), 40K (264 ± 29–462 ± 36 Bq·kg−1) were found to be all within the range of typical values reported for coastal regions. Ratios of 226Ra to 228Ra suggested accretion for all samples with low sediment accumulation registered during rainy months. In addition, vertical distributions at the three sampling sites were also studied with the initial aim of establishing chronologies from the decay of excess 210Pb. In two cores, excess 210Pb, estimated by subtracting 226Ra from total 210Pb on a layer-by-layer basis, exhibit relatively constant activity with discrete minima and maxima. Therefore, these cores were excluded from radiometric dating. Only the third core could be dated by the constant rate of supply model, and 137Cs was utilized to validate the 210Pb chronology.

Schlüsselwörter

  • The Bonny Estuary
  • Nigeria
  • gamma and alpha spectrometry
  • 210Pb
  • 137Cs
  • sediment dating
  • CRS model
Uneingeschränkter Zugang

The reflection of human activity in the sediments of Iwankowskie Lake from Subatlantic Phase (Polish Outer Carpathians)

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 377 - 391

Zusammenfassung

Abstract

The paper presents the analysis of organic and mineral sediments filling the depression, which developed over the landslide located at the slope (767–773 m a.s.l.) of Lubań ridge decscending to the Ochotnica river valley in the Polish Flysch Carpathians. The landslide formed in an early stage of the Subatlantic Phase (2490 ± 35 BP). The top of peat is dated at 1360 ± 50 years BP and is covered by 72 cm of clayey silts with some sandy intercalations, which indicate slopewash after deforestation. The pollen of ruderal plants and Cerealia (undiff.) reflect agricultural activity in the surroundings. The fragments of charcoal indicate the age of the forest clearance to the first half of the 17th century. The late forest clearance at the elevated north exposed slopes followed 200–300 years later in relation to the foundation of the village at the valley floor.

Schlüsselwörter

  • landslide peat bog
  • palaeoenvironmental interpretation
  • human activity
  • Subatlantic Phase
  • Lubań Range
  • Polish Outer Carpathians
Uneingeschränkter Zugang

Tree ring analysis as an indicator of environmental changes caused by tourist trampling — A potential method for the assessment of the impact of tourists

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 392 - 399

Zusammenfassung

Abstract

This paper shows that tree-ring trends might be used for the assessment of the intensity of trampling along touristic tracks in the forests. The study aims at determining the effects of trampling, on the dynamics of annual increments in trees subject to pressure from hiking tourism. The studies were conducted at a spruce stand in the Tatra Mts., on sections of different trails. Within each trail, four transects were determined. Transects include the zones with damage from trampling and the un-affected areas, treated as a reference zones. Selected trees growing in both zones were sampled by coring and the core samples were used to develop sequences of annual increment widths. Next, the dynamics of increments in trees growing in the tourist zone and the reference zone were compared. The decrease in the annual increments was significantly more rapid in trees growing directly along the trail that those in trees deep in the forest stand in one locality. This finding may testify the adverse effects of hiking along tourist routes on the radial increments in trees in the neighbourhood of the trails. The results of the study indicate that the impact of trampling in the form of soil compaction and mechanical damage to root systems of trees may, to some extent, be compensated by better light access and lessened competition experienced by trees growing along the edges of hiking trails. Tree-ring analyses might be an efficient alternative for assessment of tourism intensity conducted by the other methods.

Schlüsselwörter

  • dendrochronology
  • tourist impact
  • spruce forest
  • trampling
Uneingeschränkter Zugang

Stable carbon isotope analysis of subfossil wood from Austrian Alps

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 400 - 408

Zusammenfassung

Abstract

The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake — Schwarzersee, in Austria.

The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research.

Schlüsselwörter

  • stable carbon isotopes
  • subfossil wood
  • α-cellulose
  • extractives
11 Artikel
Uneingeschränkter Zugang

LA-ICP-MS U-Pb dating and REE patterns of apatite from the Tatra Mountains, Poland as a monitor of the regional tectonomagmatic activity

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 306 - 314

Zusammenfassung

Abstract

This study presents apatite LA-ICP-MS U-Pb age and trace elements concentrations data from different granite types from the Tatra Mountains, Poland. Apatite from monazite and xenotime-bearing High Tatra granite was dated at 339 ± 5 Ma. The apatite LREE patterns reflect two types of magmas that contributed to this layered magma series. Apatite from a hybrid allanite-bearing diorite from the Goryczkowa Unit was dated at 340 ± 4 Ma with apatite LREE depletion reflecting the role of allanite and titanite during apatite crystallization. Apatite crystals from a hybrid cumulative rock from the Western Tatra Mountains were dated at 344 ± 3 Ma. Apatite is one of the main REE carriers in this sample and exhibit flat REE patterns.

Taking into account the relatively low closure temperature of the U-Pb system in apatite (350–550°C), the c. 340 Ma apatite ages mark the end of high temperature tectonometamorphic activity in the Tatra Mountains.

Schlüsselwörter

  • apatite
  • U-Pb age
  • REE patterns
  • Tatra Mountains
Uneingeschränkter Zugang

The D e (T, t) plot: A straightforward self-diagnose tool for post-IR IRSL dating procedures

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 315 - 326

Zusammenfassung

Abstract

This study presents a new self-diagnose method for the recently developed post-IR infrared stimulated luminescence (pIRIR) dating protocols. This criterion studies the dependence of equivalent dose (D e) on measurement-temperature (T) and time (t), by applying the D e (t) analysis to the IRLS and pIRIR signals measured under different temperatures, and combines these D e (t) plots into one, so-called the D e (T, t) plot. The pattern of the D e (T, t) plot is shown to be affected by anomalous fading, partial bleaching and non-bleachable signal. A D e plateau can be achieved in the D e (T, t) plot only when the effects of these factors are insignificant. Therefore, this plot can be used as a self-diagnose tool for the validity of pIRIR results. The D e (T, t) analysis has been applied to four recently developed pIRIR protocols, using aeolian samples with different ages. The results show that this self-diagnose tool can be applied to different pIRIR protocols for validating the pIRIR dating results and evaluating the pIRIR measurement conditions.

Schlüsselwörter

  • post-IR IRSL
  • measurement temperature and time
  • De plateau
  • self-diagnose criterion
Uneingeschränkter Zugang

Performance tests using the Lexsyg luminescence reader

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 327 - 333

Zusammenfassung

Abstract

This study presents test measurements on a Lexsyg luminescence reader, acquired by the Giessen luminescence group. The reader is of the type Standard, hence designed for routine determination of palaeodoses using quartz or K-feldspars. The tests include measurements of the stimulation powers, preheat temperatures, OSL- and TL-curves, as well as dose recovery tests and calibration measurements using highly sensitised calibration quartz. A comparison of D e values determined using a Lexsyg reader with single grain D e-values, which have been previously obtained on a Risø reader, is also presented. The results imply that the Lexsyg reader is a highly reliable measurement device with high reproducibility, yielding instrumental uncertainties of around 0.3%.

Schlüsselwörter

  • dosimetry
  • instrumentation
  • reproducibility
  • luminescence dating
Uneingeschränkter Zugang

Estimating the number of components in an OSL decay curve using the Bayesian Information Criterion

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 334 - 341

Zusammenfassung

Abstract

The optically stimulated luminescence (OSL) decay curve is assumed to consist of a number of first-order exponential components. Improper estimation of the number of components leads to under-or over-fitting of the curve under consideration. Hence, correct estimation of the number of components is important to accurately analyze an OSL decay curve. In this study, we investigated the possibility of using the Bayesian Information Criterion to estimate the optimal number of components in an OSL decay curve. We tested the reliability of this method using several hundred measured decay curves and three simulation scenarios. Our results demonstrate that the quality of the identification can be influenced by several factors: the measurement time and the number of channels; the variability of the decay constants; and the signal-to-noise ratios of a decaying component. The results also suggest that the Bayesian Information Criterion has great potential to estimate the number of components in an OSL decay curve with a moderate to high signal-to-noise ratio.

Schlüsselwörter

  • OSL decay curves
  • number of components
  • Bayesian Information Criterion
Uneingeschränkter Zugang

Comparing different post-IR IRSL approaches for the dating of Holocene coastal foredunes from Ruhnu Island, Estonia

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 342 - 351

Zusammenfassung

Abstract

Different post-IR Infrared Stimulated Luminescence (IRSL) approaches are applied to sediments from a Holocene coastal foredune sequence on Ruhnu Island in the eastern Baltic Sea. The comparison of D e-values and ages determined by the different approaches is complimented by fading and bleaching experiments. The fading experiments imply strong fading of IRSL (50°C) signals and no fading of any of the post-IR IRSL signals, but this is not confirmed by the determined D e-values. In fact, post-IR IRSL (150°C) D e-values agree within errors with those calculated for IRSL (50°C). From the bleaching experiments it is inferred that the higher values observed for post-IR IRSL at more elevated stimulation temperatures (225°C/290°C) are likely related to either thermal transfer and/or slow-to-bleach components within the signal. For the dating of the Holocene foredune sequence of Ruhnu Island, the post-IR IRSL (150°C) approach is preferred and these agree with the limited independent age control available from radiocarbon dating. Accordingly, the sequence formed between ca. 7.0 ka and 2.5 ka ago.

Schlüsselwörter

  • luminescence
  • post-IR IRSL
  • foredunes
  • Holocene
  • Baltic Sea
Uneingeschränkter Zugang

Luminescence dating of bricks from the gothic Saint James Church in Toruń

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 352 - 360

Zusammenfassung

Abstract

Saint James Church in Toruń is one of the most important gothic monuments in Poland. The date of the beginning of its construction is known from historical reports but the earlier history of the site remains undiscovered. During the archaeological excavations in years 2010 and 2011 five brick samples were collected for luminescence dating as well as four additional samples from the brick surroundings for the dose rate estimation. The equivalent dose was determined by TL and OSL methods. The TL results differ significantly from the OSL results but the last ones are verified by historical knowledge and radiocarbon dating. Establishing the dose rate from gamma rays needs a special attention because of the complex course of the foundations of the church. The details of the applied approach are presented in the current work. The results obtained indicate that a solid brick construction existed at the site of the presbytery of the Saint James Church before it was build.

Schlüsselwörter

  • dating bricks
  • optically stimulated luminescence
  • thermoluminescence
  • annual dose
Uneingeschränkter Zugang

Optical dating and sedimentary record from the terrace depositional profile of the Warta River (Central Poland)

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 361 - 368

Zusammenfassung

Abstract

Results of OSL dating and sedimentary studies from the profile of the low alluvial terrace of the middle Warta River are presented. The samples were dated using the single-aliquot regenera-tive method. Dating was used to establish a timing of the Weichselian Late Glacial events in the river valley environment. Stable conditions on the floodplain are expressed by the deposition of organic-rich series radiocarbon dated at 12 900-12 600 cal BP and 11 600-10 770 cal BP. Samples for OSL dating were collected from the mineral material deposited during the intensification of flood events during the Weichselian decline. The results obtained for the alluvia range from 12.78 ± 0.62 ka b2k to 14.33 ± 0.74 ka b2k. Sedimentological criteria allowed to distinguish between particular flood events. Overestimation of OSL ages is probably a result of rapidity of environmental changes in that time.

Schlüsselwörter

  • palaeofloods
  • Younger Dryas
  • OSL
  • sedimentological studies
Uneingeschränkter Zugang

Sediment geochronology and spatio-temporal and vertical distributions of radionuclides in the Upper Bonny Estuary (South Nigeria)

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 369 - 376

Zusammenfassung

Abstract

Surface deposits and sediment cores were collected from the Upper Bonny Estuary, located in Southwest Nigeria, and analyzed to determine spatio-temporal and vertical distributions of radio-nuclide activities expressed in Bq·kg−1 dry weight. The results of activities of naturally occurring radionuclides of 226Ra (15 ± 2–34 ± 3 Bq·kg−1), 228Ra (32 ± 5–48 ± 6 Bq·kg−1), 40K (264 ± 29–462 ± 36 Bq·kg−1) were found to be all within the range of typical values reported for coastal regions. Ratios of 226Ra to 228Ra suggested accretion for all samples with low sediment accumulation registered during rainy months. In addition, vertical distributions at the three sampling sites were also studied with the initial aim of establishing chronologies from the decay of excess 210Pb. In two cores, excess 210Pb, estimated by subtracting 226Ra from total 210Pb on a layer-by-layer basis, exhibit relatively constant activity with discrete minima and maxima. Therefore, these cores were excluded from radiometric dating. Only the third core could be dated by the constant rate of supply model, and 137Cs was utilized to validate the 210Pb chronology.

Schlüsselwörter

  • The Bonny Estuary
  • Nigeria
  • gamma and alpha spectrometry
  • 210Pb
  • 137Cs
  • sediment dating
  • CRS model
Uneingeschränkter Zugang

The reflection of human activity in the sediments of Iwankowskie Lake from Subatlantic Phase (Polish Outer Carpathians)

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 377 - 391

Zusammenfassung

Abstract

The paper presents the analysis of organic and mineral sediments filling the depression, which developed over the landslide located at the slope (767–773 m a.s.l.) of Lubań ridge decscending to the Ochotnica river valley in the Polish Flysch Carpathians. The landslide formed in an early stage of the Subatlantic Phase (2490 ± 35 BP). The top of peat is dated at 1360 ± 50 years BP and is covered by 72 cm of clayey silts with some sandy intercalations, which indicate slopewash after deforestation. The pollen of ruderal plants and Cerealia (undiff.) reflect agricultural activity in the surroundings. The fragments of charcoal indicate the age of the forest clearance to the first half of the 17th century. The late forest clearance at the elevated north exposed slopes followed 200–300 years later in relation to the foundation of the village at the valley floor.

Schlüsselwörter

  • landslide peat bog
  • palaeoenvironmental interpretation
  • human activity
  • Subatlantic Phase
  • Lubań Range
  • Polish Outer Carpathians
Uneingeschränkter Zugang

Tree ring analysis as an indicator of environmental changes caused by tourist trampling — A potential method for the assessment of the impact of tourists

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 392 - 399

Zusammenfassung

Abstract

This paper shows that tree-ring trends might be used for the assessment of the intensity of trampling along touristic tracks in the forests. The study aims at determining the effects of trampling, on the dynamics of annual increments in trees subject to pressure from hiking tourism. The studies were conducted at a spruce stand in the Tatra Mts., on sections of different trails. Within each trail, four transects were determined. Transects include the zones with damage from trampling and the un-affected areas, treated as a reference zones. Selected trees growing in both zones were sampled by coring and the core samples were used to develop sequences of annual increment widths. Next, the dynamics of increments in trees growing in the tourist zone and the reference zone were compared. The decrease in the annual increments was significantly more rapid in trees growing directly along the trail that those in trees deep in the forest stand in one locality. This finding may testify the adverse effects of hiking along tourist routes on the radial increments in trees in the neighbourhood of the trails. The results of the study indicate that the impact of trampling in the form of soil compaction and mechanical damage to root systems of trees may, to some extent, be compensated by better light access and lessened competition experienced by trees growing along the edges of hiking trails. Tree-ring analyses might be an efficient alternative for assessment of tourism intensity conducted by the other methods.

Schlüsselwörter

  • dendrochronology
  • tourist impact
  • spruce forest
  • trampling
Uneingeschränkter Zugang

Stable carbon isotope analysis of subfossil wood from Austrian Alps

Online veröffentlicht: 01 Oct 2014
Seitenbereich: 400 - 408

Zusammenfassung

Abstract

The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake — Schwarzersee, in Austria.

The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research.

Schlüsselwörter

  • stable carbon isotopes
  • subfossil wood
  • α-cellulose
  • extractives

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