Browsing Tree-Ring Bulletin, Vol. 40 (1980) by Subjects
Now showing items 1-4 of 4
Dendroclimatic Analysis of Bur Oak in Eastern NebraskaTree-ring samples from bur oak in eastern Nebraska are analyzed and found suitable for dendroclimatic analysis. Four methods of standardization are used to develop four 233-year master chronologies. ANOVA statistics and response functions based on each chronology are examined. Response functions based on both single- station and regional climatic data are analyzed and compared. The information provided by response function analysis varies considerably depending upon choice of standardization option, number of eigenvectors extracted, and generalization of climatic data (station or region). A response function based on the polynomial chronology and 46 years of regional climatic data relates 53.4% of the chronology variance to climate and 70.4% to climate plus prior growth. The bur oak master chronology provides valuable proxy evidence for periods of moisture stress experienced during exploration and settlement of eastern Nebraska.
Eight Modern Oak Chronologies from England and ScotlandEight modern oak tree-ring chronologies are presented in index form. The sites are in Scotland and England. Chronology statistics including signal-to-noise ratios are presented, the latter ranging from 3.6 to 13.2. From calculations of response functions, the percent variance attributable to climate over a 14 month period before and including the growing season was found to range from 33 to 72 %. Classical criteria of site selection were shown to bear little relation to the final variance due to climate in the chronology.
A Medieval Oak Tree-Ring Chronology from Southwest EnglandExtensive rescue excavations in Exeter during 1972 produced large quantities of waterlogged oak timbers. These were used to construct a tree-ring chronology for the period A.D. 799-1216. The chronology crossmatches well with tree-ring sequences from other areas of the British Isles. It will thus form an important building block in the construction of a long English tree-ring curve which can be used to date archaeological timbers from most regions of Britain.
Six Modern Oak Chronologies from IrelandSix modern oak tree-ring chronologies from Ireland are presented. All are from planted or from disturbed-natural woodland of Quercus petrea. The final chronologies were tested for climate content by the response function method. The results range from 5% to 52% of the chronology variance explained by temperature and precipitation of a 14 month period during and prior to the growing periods. The relationship between these figures and the site and chronology details are examined. The relationship of the individual chronologies to each other is examined and the hypothesis put forward that Ireland can be considered as a single tree-ring area from a dating viewpoint.