210 likes | 326 Views
Dendroclimatology of Pinus resinosa at Lac Hébécourt, NW Québec Ana, Eddie, Holly, Pam, Rita, Tiffany with lots of help from Dave and Matt. OBJECTIVES Establish a chronology of earlywood, latewood, and total ring width in Pinus resinosa Compare ring width chronology from Lac Hébécourt
E N D
Dendroclimatology of Pinus resinosa at Lac Hébécourt, NW Québec Ana, Eddie, Holly, Pam, Rita, Tiffany with lots of help from Dave and Matt
OBJECTIVES • Establish a chronology of earlywood, latewood, and • total ring width in Pinus resinosa • Compare ring width chronology from Lac Hébécourt • with 2 chronologies from Ontario • Examine relationships between climatic variables • and our ring width chronologies
SITE DESCRIPTION Lac Hébécourt Islands 12, 14, and15 (SW portion of lake) Topography Steep--> gentle Soils Thin over bedrock Island vegetation Spruce, fir, red pine, cedar, and paper birch
METHODS 2 cores/tree x 30 trees from three islands (#12, 14, 15) Cores sanded and crossdated COFECHA ARSTAN Correlation Analysis
Inter-ring relationships r=0.97 r=0.65 r=0.49
r=0.14 Comparisons withother chronologies r=0.06 r=0.51
Time series of summer precipitation and latewood index r = 0.18
r = 0.11 r = 0.70
Average Temperature EW LW
Precipitation EW LW
r = -0.82 r = 0.70
CONCLUSIONS • Successfully crossdated Pinus resinosa in Lac Hébécourt, Québec • Established a 216 year chronology (1786-2001) for the area • Chronology does not compare closely with other established chronologies in region
CONCLUSIONS • Correlation between ring widths and regional climate strongest with nearby climate data • Strongest correlations between ring width indices and climatic data were: • (1) latewood index and late summer precipitation (positive) • (2) earlywood index and winter precipitation (negative)
FUTURE DIRECTIONS • Obtain better localized climate data (longer series) • Climatic reconstruction will be difficult due to the conflicting climate response of winter and summer precipitation • Control of measurement error • Complete core analysis • Further analysis of the residual and autoregressive chronologies could be explored • Compare chronologies with other species in the region for indication of pointer years