Did adaptive growth change tree sway patterns 10 years after thinning?
Based on the results of this study, it can be concluded that adaptive growth to the changed wind regime was isolated to the larger trees within the sensored area. The isolated differences found from the series of paired t-test based on DBH class was an interesting addition to the finding of the research, and was not anticipated at the start of the study. One possible reason for unevenness in the adaptive growth may be that larger trees responded rapidly to the new wind pattern by shifting carbohydrate allocation to the diameter increases. Such a shift in allocation would have allowed the larger tree to thicken in girth, becoming increasingly stable to wind forces before shifting carbohydrate allocation back to height increments or crown expansion.
Given that the larger trees experienced the greatest amount of displacement right after the thinning treatment, it can be concluded that these trees also experienced a higher rate of crown abrasion and resulting losses in leaf area. In cases where reductions in leaf area occur, energy required to adapt to new wind forces would have come from stored carbohydrates in the roots.
Given that the larger trees experienced the greatest amount of displacement right after the thinning treatment, it can be concluded that these trees also experienced a higher rate of crown abrasion and resulting losses in leaf area. In cases where reductions in leaf area occur, energy required to adapt to new wind forces would have come from stored carbohydrates in the roots.
In turn, the lack of significance between trees within the small DBH class could be attributed to the combination of lower levels of stored carbohydrate at the roots and sever losses of leaf area. Displacement results seen in Figure 4, suggest that smaller trees may have experienced some level of sheltering from the wind by the surrounding large trees, as indicated by lower levels of displacement. In such a circumstance, the smaller trees would be more likely to continue to grow in height, and less likely to allocate resources to the bole to increase diameter and provide greater tree stability. This sheltering effect may be one explanation why significance in the small DBH class was only found in the tree height comparison.
Although further research is required, the results from this study provide an interesting overview of the long term effects thinning treatments can have the dynamics of crown interactions.
Although further research is required, the results from this study provide an interesting overview of the long term effects thinning treatments can have the dynamics of crown interactions.
Disclaimer: this is a class exercise based on modified or randomly generated datasets
