Wind and gravity in shaping Picea trunks
نویسندگان
چکیده
Spruce trunk tapering corresponds closely to required resist bending forces caused by wind and gravity. Understanding why trunks (tree stems) are the size that they is important. However, this understanding fragmented into isolated schools of thought has been far from complete. Realistic calculations on minimum diameters needed moments gravity would be a significant step forward. advancements using biomechanical approach have delayed difficulties in modelling gusts. We felled measured five Norway spruces (Picea abies) an unthinned monoculture southeastern Finland planted 67 years earlier. then focused working storm-bent (maximally bent) trees strongest gust 1-h simulation with large-eddy model. The weakest points along three largest resisted mean above-canopy speeds ranging 10.2 12.7 m s−1 (3.3-fold gust), but two smallest were well protected dense layer leaves tops larger trees, could stronger winds. Gravity approximately one quarter critical moments. breaks their close breaking them other points, supporting importance evolution taper.
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ژورنال
عنوان ژورنال: Trees-structure and Function
سال: 2021
ISSN: ['0931-1890', '1432-2285']
DOI: https://doi.org/10.1007/s00468-021-02138-3