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Variations of tree ring width and chemical composition of wood of pine growing in the area nearby chemical factories

Sensuła B., Wilczyński S., Monin L., Allan M., Pazdur A., Fagel N.

Geochronometria

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2017

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Vol. 44, no. 1

226--239

EN

This study reports the variation of tree-ring widths and annual variation of concentration of metals (Na, Mg, Fe, Ni, Cu, Zn, Pb) in pine growing nearby chemical factories. The conifers (Pinus silvestris L.) investigated in this study covered the time span from 1920s to 2010 AD. Tree-ring widths were measured, dated and rechecked using the COFECHA. Radial trace-element profiles were determined by Laser Ablation Inductively Coupled Plasma Mass Spectrometry. The combined usage of tree ring width and chemical composition of wood provides historic records of anthropogenic impact on the environment and allows identifying the behavior adaptation of trees to the pollution. Data of pine tree cores collected from the sites nearby chemical factories show increasing levels of pollution linked to the increasing of industrial activities in Poland and subsequent dust fallout around the site. This study evidences that tree rings can be used as archives of past environmental contamination.

2

Some considerations in the reconstruction of lead levels using laser ablation: lessons from the design stage of dendrochemistry study, St.John's, Canada

Danek M., Bell T., Laroque C. P.

Geochronometria

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2015

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Vol. 42, no.1

217--231

EN

Study of soils in St. John’s, Canada showed elevated Pb levels representing a potential ex-posure risk for young children. Old trees growing in the city present a potential annually-resolved record of Pb levels over past centuries that provides important temporal and spatial dimensions to Pb exposure risk assessment. This paper reports the results of our analytical tests to develop a fast, reliable and cost-efficient method using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for measuring Pb concentration in annual tree rings from available tree species. Our tests focused on approaches to sample preparation as they affect the laser ablation process, the relative merits of the ablation sampling method, and the response of our available tree species, which have contrasting wood structures, to laser ablation. The range of annual Pb concentrations (ppm) measured for each of the study species were as follows: spruce (0.18–6.42); elm (0.12–7.91); and horse chestnut (0.40–14.09). Our results demonstrate that the cutting procedure for preparing tree cores produced the most consistent Pb concentrations of the three methods, although they each displayed problematic anomalies. The selection of the best laser ablation technique appears to be highly dependent on study species and goals. In general, spot analysis permits detailed and targeted studies of tree-ring structures, but requires careful sampling attention for species with complex wood anatomy. The line scan method is ideal for reconstructing annually resolved element concentrations from trees and to some degree mitigates the complicating issue of intra-ring variability. Horse chestnut was determined to be the best of the available tree species because it exhibited a good response to laser ablation and produced the lowest intra-ring variations in Pb concentration.

3

Exploring Growth Variability and Crown Vitality of Sessile Oak (Quercus petraea) in the Czech Republic

Rybníček M., Čermák P., Žid T., Kolář T., Trnka M., Büntgen U.

Geochronometria

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2015

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Vol. 42, no.1

17--27

EN

Unraveling climatic effects on growth of oak — Europe’s most ecologically and economically important forest species — has been the subject of many recent studies; however, more insight based on field data is necessary to better understand the relationship between climate and tree growth and to adapt forest management strategies to future climate change. In this report, we explore the influence of temperature, precipitation and drought variability on the productivity and vitality of oak stands in the Czech Highlands. We collected 180 cores from mature oaks (Quercus petraea) at four forest stands in the Czech Drahany Highlands. Standard dendro-methods were used for sample preparation, ring width measurements, cross-dating, chronology development, and the assessment of growth-climate response patterns. Crown vitality was also evaluated, using the modified ICP Forests methodology. Late spring precipitation totals between May and June as well as the mean July temperature for the year of ring formation were found to be the most important factors for oak growth, whereas crown condition was significantly affected by spring and summer drought. This study is representative for similar bio-ecological habitats across Central Europe and can serve as a dendroclimatological blueprint for earlier periods for which detailed meteorological information is missing.

4

Tree-ring based temperature reconstruction for the west Qinling Mountains (China): linkages to the High Asia, solar activity and Pacific-Atlantic Ocean

Chen F., Yuan Y., Wei W., Yu S., Shang H., Zhang T., Zhang R., Wang H., Qin L.

Geochronometria

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2014

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Vol. 41, no. 3

234--244

EN

We developed a Faxon fir (Abies faxoniana) tree-ring width chronology at the timberline in the western Qinling Mountains, China. Herein February–July mean temperature was reconstructed for Zhouqu in the western Qinling Mountains back to AD 1650 based on the standard chronology. The climate/tree-growth model accounts for 43.5% of the instrumental temperature variance during the period 1972–2006. Spatial correlation analyses with the gridded temperature data shows that the tem-perature reconstruction captures regional climatic variations over central and southeast China, and strong teleconnections with the nearby High Asia. There is a good agreement with cold and warm pe-riods previously estimated from tree-rings in Nepal, India and southwest China. The temperature re-construction indicates that there was pronounced cooling in Zhouqu during the Maunder Minimum (late 1600s to early 1700s). The cold period (1813–1827) of the temperature reconstruction coincide with the volcanic eruptions. Significant spectral peaks are found at 56.9, 22.3, 11.4, 2.9, 2.8, 2.6, 2.2 and 2.0 years. The spatial correlation patterns between our temperature reconstruction and SSTs of the Atlantic and Pacific Oceans suggest a connection between regional temperature variations and the atmospheric circulations. It is thus revealed that the chronology has enough potential to reconstruct the climatic variability further into the past.

5

Oak decline in a southern Finnish forest as affected by a drought sequence

Sohar K., Helama S., Läänelaid A., Raisio J., Tuomenvirta H.

Geochronometria

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2014

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Vol. 41, no. 1

92--103

EN

We investigated the decline of a pedunculate oak (Quercus robur L.) forest growing on shallow soil at the northern distributional limit of the species in southern Finland, using the dendro-climatic approach. About 200-year-old trees in three vigour classes – healthy, declining and dead – were sampled in 2008. Annual tree-ring, earlywood and latewood widths were measured and chro-nologies were established. The tree-ring data were correlated with monthly and seasonal climate data. Radial increment of oaks was positively related to the June and July precipitations. This was ex-pressed especially in total ring width and latewood width, whereas the earlywood was more influ-enced by the warmer winter and spring. Furthermore, the correlation between the current year ear-lywood width and the preceding year latewood width was higher than between the earlywood and latewood of the same year. The analyses showed that the dead oaks and part of the declining oaks had ceased growing during 2005-2007 after a decade-long summer drought series. This indicates a time lag in the oak dieback. The radial growth of the declining and the dead oaks had dropped already since the 1990s, while the healthy oaks had better long-term growth and higher adaptive capacity to climate variation.

6

Weryfikacja prognoz okresowych zmian temperatury powietrza w Warszawie w latach 1779-2010

Boryczka J., Stopa-Boryczka M., Kossowska-Cezak U., Wawer J.

Przegląd Geofizyczny

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2012

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Z. 3-4

343-362

PL

Zweryfikowano prognozy klimatu powstałe w Zakładzie Klimatologii UW, podejmowane (przez J. Boryczkę ze współautorami) kilkakrotnie na podstawie najdłuższej w danym czasie serii obserwacyjnej z Warszawy, tj. od 1779 roku. Porównano zmierzone wartości temperatury powietrza w Warszawie-Okęciu w latach 1951-2010 z prognozowanymi z wyprzedzeniem 31 lat i 20 lat. Dobrą sprawdzalnością cechują się prognozy temperatury powietrza w Warszawie na lata 1980-2010 i 1991-2010 z 1984 i 2000 roku, według cykli wykrytych metodą "sinusoid regresji" w seriach wyników pomiarów w Warszawie-Obserwatorium Astronomiczne. Ta pozytywna ocena prognoz wynika z synchronicznych przebiegów wieloletnich wartości zmierzonych i obliczonych (wypadkowa interferencji cykli), a także z istotnych statystycznie związków korelacyjnych (na poziomie ufności 95%). Prognozy zmian klimatu np. półkuli północnej, wynikające z interferencji długich cykli promieniowania słonecznego oraz cykli zawartości izotopu tlenu δ^18 O, w rdzeniach lodowych Arktyki δ^18 O wymagają dłuższych serii pomiarów.

EN

This paper offers a verifi cation of the climate forecasts developed at the Department of Climatology of the University of Warsaw (by J. Boryczka and co-authors) as part of a series of observations in Warsaw that commenced in 1779. The air temperatures recorded at Warsaw-Okęcie in 1951-2010 were compared with those predicted for the period 1980-2010 and 1991-2010, i.e. 31 and 20 years in the future. Accurate predictions of air temperatures in Warsaw in 1980-2010 and 1991-2010 from 1984 and 2000 were obtained by using the cycles identifi ed by applying the sinusoidal regression method to a series of monitoring results in Warsaw from 1779 to 1979. The good accuracy of these forecasts is a result of a similar progression of measured and forecast values over a number of years. The prediction of climate change, for example in the Northern Hemisphere caused by interference of long solar radiation cycles as well as variations in the concentrations of the δ^18 O oxygen isotope in the Arctic ice cores, requires a larger series of data points.

7

The permutation test for testing the statistical significance of the power spectrum estimation in dendrochronological analysis

Krawczyk A.

Geochronometria

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2010

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Vol. 36

23-29

EN

The study presents a proposal of application of the statistical permutation test, known from other applications, for searching for the symptoms of cyclicity, in particular related to solar activity, in the annual growth sequences of trees. The test consists in generation of random sequences of the increment widths observed and comparison of their periodograms with the periodogram of the sequence analysed. This allows for evaluation of the significance of the individual frequencies in the total variability. The model calculations carried out indicate that in the studies on cyclicity in dendrochronological sequences satisfactory results could be obtained in the analysis of sets of the individual sequences (but not the chronologies produced from them). It is important to generate sufficiently high numbers (1000 and more) of random sequences and to apply relatively low significance levels (at 0.05, or even 0.01).

8

The benefits of tree-ring curves detrending for dating archaeological wood

Rybníček M., Koňas P., Kolář T.

Geochronometria

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2010

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Vol. 35

85-90

EN

During the process of developing the standard chronology for oak for the Czech Republic, two versions of standard chronology were determined: the standard chronology developed using detrended tree-ring series and the standard chronology developed using non-detrended tree-ring series. These standard chronologies were applied to date detrended and non-detrended average tree-ring curves obtained from dendrochronological samples from selected archaeological locations. The highest values of the t-test were achieved when comparing the detrended or non-detrended average ring curves only and exclusively with the detrended standard chronology. Similarly, the highest percentage of the curve parallelism was always obtained in comparison with the detrended standard chronology. The confidence and, more importantly, the prediction intervals of the detrended ring curves are considerably smaller than those of the non-detrended ones. The regression curves of the detrended standardised values of the ring curves are more similar to the calibration curve than the non-detrended ones. The significance level of the regression models in the detrended ring curves is notably higher, than in the case of the non-detrended ring curves. The differences established between the detrended and non-detrended standard chronology have highlighted the importance to develop detrended standard chronologies.

9

Adial growth and health condition of norway spruce (Picea abies (L.) Karst.) Stands in relation to climate (Silesian Beskids, Czech Republic)

Rybníček M., Čermák P., Žid T., Kolář T.

Geochronometria

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2010

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Vol. 36

9-16

EN

The research was conducted in selected spruce stands of the Silesian Beskids aged over 70 at altitudes from 403 m a.s.l. to 794 m a.s.l. in 2008. The samples were taken and processed in compliance with standard dendrochronological methodology. Tree rings were measured and the treering curves were synchronized using the PAST4 application. The age trend was removed in the ARSTAN application and the climatic influences were modelled in the DendroClim application. The regional standard tree-ring chronology shows an obvious decrease in the radial increment from the beginning of the 1970s to the mid-1990s. The gradual increase in radial increment which followed in the second half of the 1990s was interrupted in 2000, 2003, and 2006. Most of the years with the decreased radial increment have been confirmed by the analysis of significant negative years. The radial increment statistically significantly correlates with the precipitation in July and September of the previous year, precipitation in June of the year in question and precipitation during the vegetation period. Moreover, the growth of spruce is statistically significantly affected by temperatures in October of the previous year and March of the year in question. Additionally, the paper includes habitual monitoring of trees and the volume of salvage cutting in these districts. The condition of the habit of trees and the development of salvage cuttings agree with the hypothesis about strong stress load or its considerable increase in 2003 and the following years.

10

Influence of climate on radial growth of Holm Oaks (Quercus ilex subsp. ballota Desf) from sw Spain

Patón D., García-Herrera R., Cuenca J., Galavis M., Roig F. A.

Geochronometria

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2009

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Vol. 34

49-56

EN

A total of 47 trunk sections from Holm Oak (Quercus ilex subsp. ballota Desf) trees growing at two different sites at the Extremadura region (SW Spain) were considered in the computation of a regional tree-ring chronology useful to interpret the tree-ring/Mediterranean climate relationships. This is the first dendroclimatological research of Holm Oaks conducted to reveal its potential use as a climatic proxy. The obtained tree-ring chronologies were compared with climatic parameters based on monthly, seasonal and annual rainfall, and monthly maximum, minimum and average temperature. The best correlations were obtained with maximum temperatures during the period between previous winter and early spring. Influence of rainfall was less relevant. Growth of this species indicates a typical bimodal (spring and autumn) strategy that avoids low winter temperatures and summer drought. Despite some technical difficulties recognizing tree rings in Holm Oaks, its good sensitivity to climate variability and its wide distribution and longevity (∼ 800 years), allow us to consider this species as a good candidate for temperature reconstructions in the Mediterranean Basin.

11

Carbon-14 in tree rings in the vicinity of Ignalina Nuclear Power Plant, Lithuania

Mazeika J., Petrosius R., Pukiene R.

Geochronometria

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2007

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Vol. 28

31-37

EN

The results of 14C measurements in the annual tree rings from the Ignalina Nuclear Power Plant (INPP) vicinity, Lithuania, for the period of its operation from 1984 to 2002 are presented. The terrestrial samples, mainly moss and related topsoil, are studied in places as well. The tree rings have shown the slightly enhanced 14C activity due to operation of the nuclear power plant. The maximal calculated normalized 14C release of 11 TBq/GWe/year and the maximal effective dose of 2.0×10-3 mSv/year resulting from the 14C were estimated for 1999. The excess of 14C specific activity measured in the moss and soil samples from moss-covered sites near the nuclear power plant (up to 0.5 km) showed highly elevated 14C contents (up to 813 pMC), probably indicating releases of the particulate material.

12

Erozja wąwozowa zapisana w odsłanianych korzeniach drzew na Wysoczyźnie Proboszczowickiej pod Górą Św. Anny

Malik I.

Przegląd Geologiczny

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2006

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Vol. 54, nr 4

326-332

EN

Erosion occurs in permanent gullies cutting into the undulating loess plateau in southern Poland. The gully slopes are mainly vegetated with beech trees as opposed to the surface of the plateau summit, which is cultivated agricultural land, devoid of forests for at least 18 centuries [od 18 wieków czy od XVIII wieku – czyli “since 1700s”?]. Beech roots are exposed in the gullies through erosion. Wood cells in the tree rings divide into early wood and late wood and, after the roots are exposed, also start to make fewer cells. In the roots on the border between exposed and unexposed tree rings in the tree roots, scars sometimes occur. This is an effect produced by corrasion by dolomites and limestones lying under the loess cover and re-deposition of building material stored by people in the higher part of the gullies. These anatomical changes in root tree rings allow one to date erosion episodes. Dating of the exposure of roots indicates that intensive erosion took place in the gullies starting in the 1980s. Since that time, numerous extreme rainfall events responsible for initiating erosion have also occurred. They contribute to deepening valleys causing new incisions to develop on hillslopes and headcut retreat in upper parts of the valleys studied at theWysoczyna Proboszczowicka near Góra św. Anny. The bottom of the valley head eroded during extreme rainfall events in 1984 and 1991. Erosion here alternates with deposition, its speed being relatively small. Incisions in hill slopes retreated during the flood in 1997, but they originated during earlier rainfall episodes. Such incisions retreat 2.5–3 m/year, i.e., relatively fast.

13

A boreal-temperate transect in Europe : history of pine stands reconstructed from the radial growth of trees

Parn H.

Polish Journal of Ecology

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2003

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Vol. 51, nr 4

413-420

EN

History of the Scots pine sites along the Finland-Poland boreal-temperate transect along 25 stopni E longitude, ranging from 50 stopni N - 70 stopni N latitude (see Fig. 1 in Breymeyer 2003) was reconstructed using tree-rings. The correlation between the tree-ring index chronologies for the sites was studied. The age of trees at particular sites varies in the range from 66 to 178 years. The youngest trees are growing at the sites FH3 and PL3, the eldest at FN1. At the sites FN1 and PL1, two groups of trees of different age were separated. Correlation analysis revealed significant correlation among the Baltic chronologies. High correlation coefficients were also found between the PL2 site chronology and all the Baltic state chronologies. No positive correlation was detected among the chronologies from the sites in Finland and in Poland.