1 / 19

D 14 C

D 14 C. d 18 O. d 13 C. d 2 H. www.carbon14.pl. Mariusz Fogtman and Anna Pazdur Silesian University of Technology Department of Radioisotopes. INTRODUCTION.

lana-kane
Download Presentation

D 14 C

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. D14C d18O d13C d2H www.carbon14.pl Mariusz Fogtman and Anna Pazdur Silesian University of Technology Department of Radioisotopes

  2. INTRODUCTION Scientists can use the tree rings for reconstructing past climate because trees are good environmental indicators. They produce very small rings during years of drought and large rings during years of good growing conditions.  By counting the rings from the middle of the trunk, and studying the width of the rings, scientists can reconstruct an approximate calendar of wet and dry years. Scientists assume that the weather affected ancient tree ring growth the same way it does today. Scientists can also date the occurrence and frequency of fires by finding scars that appear in the growth rings. Additionally measurement of isotopic ratios e.g. d2H, d13C, d18Oand others in annual tree rings by mass spectrometer allows to track the isotopic ratios changes to determine the climate conditions in the past.

  3. CHARACTERISTIC OF TREE COMPONENTS Trees go through annual cycles of growth. Roots are busy in the early spring and late fall. Leaves and twigs grow in spring and the tree adds wood all summer long. http://www.na.fs.fed.us/spfo/pubs/uf/treeguidehtm/chapter4.htm

  4. INSIDE THE TREE Cross-section of the tree trunk.

  5. INSIDE THE TREE Tree ring widthVariability of tree ring width and climatic conditionsSeasonal patterns:          Early wood Large, thick-walled cells           Late wood Small, densely-packed, thin-walled cells           Together = an annual growth ring Mean width of rings dependant on:          tree species           tree age           availability of stored food           climate (precipitation, temperature, humidity, sunshine,           windspeed, humidity) Trees as filters and sources of palaeoclimatic data

  6. TREE SAMPLING TREE SLICE SAMPLING TREE CORE SAMPLING Collection of the tree slice Increment borer Two kind of tree sampling for dendrochronology measurement Tree slice surface preparation by polishing Choice of the suitable part of tree slice for dendrochronology measurements. Tree core

  7. TREE RINGS MEASUREMENT Device for tree ring width measurement LINTAB in Gliwice Tree Ring Laboratory Measurement precision is 0,01 mm.

  8. TREE RINGS MEASUREMENT Each tree should be measured at least in two radiuses. The final results is mean from each radius of adequate tree ring measurement.

  9. Bark Pith UNDER THE MICROSCOPE Microscope view of pine (Pinus Sylvestris) slice. This part shows annual tree growths close to tree pith.

  10. Bark Pith UNDER THE MICROSCOPE

  11. Bark Pith UNDER THE MICROSCOPE In some cases tree growths are very thin (e.g. during the drought). In this picture annual growths with very small width 0,3 – 0,8 mm are shown.

  12. REGISTRATION OF MEASUREMENT DATA TSAPWin Basic 1.15b Program for registration tree measurement data.

  13. EXAMPLES OF DENDROCHRONOLOGY MEASUREMENT This pine slice comes from Niepołomice Forest, near Cracow.

  14. EXAMPLES OF DENDROCHRONOLOGY MEASUREMENT This pine slice also comes from Niepołomice Forest, see the similarity of dendrochronology measurement on plots.

  15. CHRONOLOGY For investigations of climate condition changes in the past, on the basis of dendrochronology measurement, the calendar scale must be prepared. In this fact the tree rings from different trees are compared for construction of complete chronology.In many cases tree rings width were correlated with dendrochronology standard adequately for investigated tree species.This correlation allows to match the measurement of tree rings width to the calendar years. Different sources of dendrochronology material Matching of tree rings width or indices Chronology

  16. ISOTOPIC COMPOSITIONS IN TREES Atmospheric CO2 d34S d13C Light d15N d18O Precipitation d18O ‰ ‰ d2H ‰ ‰ ‰

  17. PREPARATION OF SINGLE TREE RINGS Tree slice was cut by small chisel After that, wood sample is cut for small pieces for chemical treatment Combustion to CO2 for GPC measurement Resin and dyes removes Benzene production for LSC measurement cellulose production for stable isotope concentration measurement Boiling samples in laboratory bath several hours in 90ºC for removing of rest of chemicalmixture. Next samples are dried. Chemical treatment in Soxlet’s columns. Wood is in cotton bags. Wood samples are rinsed in benzene/alcohol mixture (2/1 proportion)

  18. MEASUREMENT OF ISOTOPES RATIOS IN TREES CO2 Benzene Cellulose GPC LSC MASS SPECTROMETER AMS d13C d2H d18O d15N d34S D14C

  19. THE END www.carbon14.pl

More Related