Relationship of tree growth to climate in the Nechako region of central interior British Columbia

Abstract

Relationships between tree growth and climate can be found using dendroclimatology, and are important as a basis for understanding regional limiting factors of growth and projecting how forests might be altered by climate change. This study aims to determine factors limiting growth of coniferous trees in the Nechako region of sub-boreal Central-Interior British Columbia by studying tree growth-climate relationships at the Carrot Lake Experimental Fire Study area. Trees cores were collected from the study area in 2012 then processed and analyzed in 2014. Ringcounting of cores from Lodgepole Pine and White Spruce trees indicated samples had ages of 127-136 years. Tree ring chronologies were standardized, verified by cross-dating, and pre-whitened for dendroclimatology analysis. A simple linear regression comparison of ring widths against summer temperature and precipitation data from nearby weather stations showed there was a statistically significant, positive correlation between annual ring growth and precipitation in the month of May (standardized R2 = 0.06128, pre-whitened R2 = 0.05635; n = 9). This indicates a growth-precipitation relationship during the beginning of the growing season, where more rain results in greater growth. Due to the small, localized sample size used in this study these findings may only represent the mesoclimate of the Carrot Lake Experimental Fire study site. Nevertheless, this study may be the basis for future research that can provide better insight into the climate history
for the region, as well as projections of climate change impacts on the forests of British Columbia.