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Selected approaches of climate-growth relationship determination of trees
Pekař, Ondřej ; Treml, Václav (advisor) ; Ponocná, Tereza (referee)
Presented bachelor thesis describes the use of tree-ring widths in dendroclimatology and main approaches of climate variables reconstruction. It reviews the basics about climate influence on tree- ring fromation and extraction of climate signal from tree-rings. Main standartization methods were used to develop 26 standard and residual chronologies from adjusted and not adjusted tree-ring series coming from high-elevation Norway sporuce stands. Chronologies were compared in terms of correlation with summer temperatures. The best correlated temperature variable were the June-July temperatures both for standard and residual chronologies. Tree-ring width chronologies were scaled to observed June-July temperatures. Based on comparison of scaled and real June-July temperatures, negative exponential function and RCS method appear to be the most suitable to preserve both high and low frequency climate signal. Key words: Dendroclimatology, tree-rings chronology, standardization, climate reconstruction
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Sensitivity of Scotch pine ring-width chronologies to climatic variables
Lehečková, Eliška ; Treml, Václav (advisor) ; Vejpustková, Monika (referee)
Presented master's thesis deals with the climate sensitivity of radial growth of Scots Pine (Pinus sylvestris) growing in the Protected Landscape Area Kokořínsko. The principal aim was to find out whether there are differences in the climate-growth response of pines growing on dry and mesic sites. To cope with that question tree ring cores were collected from stands on dry sandstones plateau and from stands near valley bottom with better water supply. Residual chronologies were developed and climatic factors limiting growth were identified using partial correlation analysis. The results show that pines on rocky sites respond positively to high precipitation during the vegetation season whereas trees on wetter sites react positively to high temperatures. In most study stands high February temperatures positively affect radial growth. Moving partial correlations analysis showed that the strongest responses to month climatic variables were stable over the studied period 1902 - 2009. Pointer years were determined and compared with precipitation and temperature anomalies in the corresponding pointer year, furthermore the effect of climate on number of trees with growth anomaly was studied using partial correlations analysis. Results of these analyses were in compliance with the previous findings. In...
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