Radial Growth Responses of Four Deciduous Species to Climate Variables in Central Ontario, Canada

To address the central question of how climate change influences tree growth within the context of climate will become warmer and drier in central Ontario, we used dendroclimatological analysis to understand the radial growth responses of four co-occurring hardwood species: sugar maple (Acer saccharum Marsh.), yellow birch (Betula alleghaniensis Britton), American beech (Fagus grandifolia Ehrh.), and red oak (Quercus rubra L.) to climatic variables in central Ontario, Canada. Ring width chronologies were developed for the target species within three regions (Algonquin Park, Haliburton, and North Bay) of the study area. Seven of the eleven chronologies exceeded the 0.85 expressed population signal (EPS) and were used for further analysis. Mean sensitivity and standard deviation values of the Ontario chronologies indicated lower sensitivity to climate fluctuations than in southern North America. Positive correlations with precipitation variables from the current and prior growing season supported previous studies in sugar maple, while a positive response to growing degree days suggested the importance of warmer temperatures and a longer growing season at the northern limit of the distribution range of sugar maple. Yellow birch ring width was correlated with precipitation from the previous growing season and from the end of the current growing season also suggesting that mature trees with deep root systems might utilize moisture from deep soil. Radial growth of American beech positively correlated to precipitation of the previous season, suggesting that the amount of moisture reserves stored in the previous year might affect growth in the following year. Drought stress at the start of the growing season for red oak had negative correlations with precipitation in August indicating possible cessation of cambial activity. This decline in growth process would also affect ring width of red oak the following year as expressed by negative correlations with mean annual temperature from the previous year. Abnormally, warm seasonal temperatures may be indicative of drought stress in red oak.

来源: Radial Growth Responses of Four Deciduous Species to Climate Variables in Central Ontario, Canada

Advertisements

发表评论

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / 更改 )

Twitter picture

You are commenting using your Twitter account. Log Out / 更改 )

Facebook photo

You are commenting using your Facebook account. Log Out / 更改 )

Google+ photo

You are commenting using your Google+ account. Log Out / 更改 )

Connecting to %s