AUTHOR=Li Weixin , Yue Fengxin , Wang Chunkai , Liao Jinglei , Zhang Xianliang 

TITLE=Climatic influences on intra-annual stem variation of Larix principis-rupprechtii in a semi-arid region

JOURNAL=Frontiers in Forests and Global Change

VOLUME=5

YEAR=2022

URL=https://www.frontiersin.org/journals/forests-and-global-change/articles/10.3389/ffgc.2022.948022

DOI=10.3389/ffgc.2022.948022

ISSN=2624-893X

ABSTRACT=<p>Intra-annual monitoring of stem radial growth dynamics of trees and detecting how tree growth responds to changing climatic conditions are crucial for predicting the future growth dynamics under increasing drought conditions. Here, we monitored the intra-annual stem radial growth dynamics of seven <italic>Larix principis-rupprechtii</italic> using point dendrometers to investigate the influence of climate variables on the intra-annual growth of <italic>L. principis-rupprechtii</italic> in the growing season. The average stem radial growth of <italic>L. principis-rupprechtii</italic> started on 29 April and stopped on 17 August based on the sigmoid Gompertz functions. The intra-annual stem radial growth of <italic>L. principis-rupprechtii</italic> showed a parabolic trend, with its growth decreased when the temperature and sunlight duration hours exceeded certain thresholds. The vapor pressure deficits (VPD) strongly influenced tree intra-annual growth over other climatic factors in the growing season. Stem radial growth of <italic>L. principis-rupprechtii</italic> decreased significantly with increasing VPD when VPD ranged from 0.5 to 0.8 kPa. Intra-annual stem radial growth of <italic>L. principis-rupprechtii</italic> was severely inhibited when VPD was higher than 0.8 kPa. In contrast, tree stem radial growth reached the maximum when VPD was lower than 0.5 kPa. Our study highlighted the important influences of major limiting climatic factors on the stem radial growth of trees in semi-arid regions.</p>