110 research outputs found
Klimato sąlygų poveikis paprastosios pušies metiniam prieaugiui Aukštaitijos nacionaliniame parke (Lietuva)
 
Stable carbon isotope ratios of tree-ring cellulose from the site network of the EU-Project ‘ISONET’
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Dendrochronological Analysis Of Subfossil Fraxinus From The Middle And Late Holocene Period In Lithuania
Dendrochronological investigations on subfossil European ash (Fraxinus excelsior L.) wood found in two bogs of Western Lithuania are presented. Radiocarbon dating has revealed that Fraxinus grew in the Middle and Late Holocene, from approximately 4700 BC to 1500 BC. It is proposed that the growth of Fraxinus at these bogs was limited by differing hydrological regimes. Rising soil water levels induced a long decline in radial growth followed by a sharp reduction (up to 51%) in ring widths before the trees died. Until now, forest history in Lithuania was mostly based on results from palynological studies. This research demonstrates the potential of using dendrochronology to extend the distribution record of Fraxinus in the Baltic region during different periods of the Holocene.This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]
Lietuvos istorinių pastatų pušies medienos datavimas
Thirty samples from Scots pine (Pinus sylvestris L.) timber taken from historical buildings of Lithuania were precisely dated and together with living pines used for construction of the long-term chronology. Samples were taken from churches, monasteries and estates located in the central – Kaunas region (Kaunas Karmelitai Church, Kaunas Jezuitai Church, Kaunas City Hall, Aukstoji Freda Estate, Zapyskis Church and Skaruliai Church) and eastern – Vilnius region of Lithuania (Vilnius Evangelikai Reformatai Church, Vilnius Benediktines Church, Vilnius Benediktines Monastery, Vilnius Sv. Mykolas Church, Vilnius Trinitoriai Monastery, Vilnius Cathedral and Vilnius City Hall). Th e most valuable material – samples containing more than 100 rings mainly are from old churches and monasteries in Vilnius region. For the dating of younger samples we used two chronologies compiled from living pine trees: Vingis Park – 24 trees (1673-1989) from Vilnius and Panemune Silas – 8 trees (1783-2002) from Kaunas. Th ese two chronologies show very similar radial growth patterns. For the dating of older material, especially from Vilnius churches, we used successfully two longterm pine chronologies: Dannenstern House from Latvia by dr. Maris Zunde (1445-1740) and Polpinus- 5 from Poland by dr. A. Zielski (1106-1991). Dating results showed that the pine timber material mainly used in the constructions of Lithuanian Churches and Monasteries is from middle of the 17th century up to middle of the 19th century. Th is means that the material from older periods is quite almost lost during the war fi res in the middle ages and the biggest amount of taken samples are representatives of the reconstruction worksVytauto Didžiojo universiteta
Paprastosios eglės (Picea abies L. Karst.) rievių reperiniai metai sausose augavietėse Lietuvoje
Research material (samples from tree stems) in all regions of Lithuania during 1995-2000 was collected. More than 50 research plots in mature Norway spruce forests were selected. Most of these plots (34) represent dry forest sites (Piceetum vaccinio-myrtillosum and Piceetum hepatico-oxalidosum). More than eight hundred tree-ring series from spruce trees were analysed. Latewood and earlywood widths were measured separately. During the research, two master chronologies (one for each site) were created. Using response function the correlation between tree-ring growth and meteorological factors (monthly precipitation and air temperature) was estimated. Pointer years of spruce radial increment during past sixty years were also estimated. The following significant pointer years with negative increment were identified: 1941, 1954, 1979, 1980, 1992 and 1993. Characteristic pointer years of positive increment were in 1946, 1961, 1962 and 1974. There are no clear differences in the geographical distribution of pointer years in 1946, 1954, 1962 and 1992. There are only differences in comparison between annual ring, latewood and earlywood increment in these years. Results of my research on Norway spruce have showed that even in a small territory like Lithuania (slightly bigger than 65 thousands km2), with hills no higher than 300 meters, there are significant differences in widths of tree ringsVytauto Didžiojo universiteta
Dendroklimatologinis paprastosios pušies (Pinus sylvestris L.) tyrimas Lietuvos pajūryje
Aplinkos tyrimų centrasVytauto Didžiojo universiteta
Dendroclimatological study on the radial growth of European larch (Larix decidua Mill.) in Lithuania
Larch trees were planted in Lithuania at the beginning of the 19th century. European larch is one of the most beautiful planted trees in Lithuanian parks and forests. The influence of climatic factors on treeͲring formation of larch in Lithuania is not adequately studied. Earlier results based usually on several trees or few experimental plots and applying different methodology have provided controversial results. It was known that the radial growth of larch in Lithuania is tolerant to winter colds as well as the significant role of climatic conditions in previous season. This study was aimed at investigating the climate/radial growth relationships of larch using response function and pointer year analysis in a network of experimental plots in Lithuania. Moreover, we have investigated the interͲrelationships between negative pointer years and light rings of larch. 26 research plots (357 mature larches) were selected in larch stands in Lithuania. TreeͲring widths were measured using an image analysis technique. Then, the crossͲdating and standardization were carried out and local chronologies were compiled. The response function analysis was carried out in 17 plots from 1950– 2003. The stability of relationships was tested in three longest larch chronologies using moving intervals from 1895–2006. Response function has demonstrated that the radial growth of larch is inversely related to air temperature in previous June – September, while the relationships in previous July are statistically significant in all regions and stable from 1895–2006. The influence of air temperature in April and May is positive and increasing. The relationships in January are higher in Eastern Lithuania. However, coefficients are decreasing. The relationships with precipitation are usually positive across Lithuania, but more variable than the relationships with air temperature.[...]Aplinkos tyrimų centrasVytauto Didžiojo universiteta
Paprastosios pušies (Pinus sylvestris L.) radialiojo prieaugio dinamikos klimatologinė analizė 1550-2002 m
Vytauto Didžiojo universiteta
Paprastosios pušies (Pinus sylvestris L.) medžio rievių chronologija Lietuvai
The long-term Scots pine tree-ring chronology developed from historical timber and living trees from Lithuania is presented. The chronology involves dated 65 tree-ring width series (33 timber samples and 32 living trees) and runs for 516 years between 1487 and 2002. Constructed chronology shows strong trans-regional signal – high similarity to centennial pine chronologies developed for Poland, Latvia and Estonia. Pointer year analysis has revealed that colds in winter-spring and droughts in summer are the main causes for the sharp decrease of the radial growth. Five negative pointer years cannot be linked to climate events because of the lack of historical records in the pre-meteorological periodAplinkos tyrimų centrasVytauto Didžiojo universiteta
Šimkaičių Šv. vyskupo Martyno bažnyčios dendrochronologiniai tyrimai atskleidžia Girkalnio koplyčios istoriją
Aplinkos tyrimų centrasVytauto Didžiojo universiteta
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