Analysis of tree sway and crown collisions for managed Pinus resinosa in southern Maine

作者：Webb Vincent A; Rudnicki Mark^*; Muppa Shravan Kumar

来源：Forest Ecology and Management, 2013, 302: 193-199.

DOI：10.1016/j.foreco.2013.02.033

• Canopy
• Crown collisions
• Oscillation frequency
• Scaling analysis

In this experimental analysis, we attempt to determine if and how the oscillation frequencies of trees in a real forest stand vary. We examined the oscillation dynamics of trees in a red pine plantation before and after the stand was thinned from an initial density of approximately 1400 trees/ha to a final density of approximately 200 trees/ha. The prescribed thin effectively prevented collisions from occurring in the post-thin canopy under low and moderate wind conditions. A comparison of the pre-thin and post-thin canopies suggests that crown collisions increased the oscillation frequencies of individual trees in the stand by an average of 12.0%. We used several scaling relationships to estimate that collisions reduced tree sway amplitudes by an average of 32%. These findings are consistent with theoretical predictions from an elastic collision model of crown interactions which predicts that oscillation frequencies should increase as the wind speed increases. However, we did not find conclusive evidence of this latter behavior in the real stand, perhaps because of the limited range of wind speeds occurring during our trial.

• 出版日期2013-8-15