东北林业大学学报2026，Vol.54Issue(10)：72-82,11.
干旱对西双版纳望天树液流密度的影响
Effects of Drought on Sap Flow Density of Parashorea chinensis in Xishuangbanna
摘要
Abstract
To reveal the dynamic patterns of sap flow density and its response relationships with environmental factors in Para-shorea chinensis under drought conditions,we took P.chinensis in Xishuangbanna as research material and conducted ana-lyses on the effects of drought on sap flow density based on auxiliary observation plots in the artificial tropical rainforest of Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences.The results showed that:(1)The seasonal dy-namics of sap flow density of P.chinensis were characterized by high values in the rainy and fog-cool seasons and low val-ues in the hot-dry season.However,its fluctuations intensified markedly in 2020,which was identified as a year with per-sistent drought throughout the year according to the Palmer drought severity index(PDSI).(2)Regression analysis indi-cated that the sap flow density of P.chinensis in normal years was primarily regulated by different environmental factors in each season(P<0.05):photosynthetically active radiation(R2≥69%)in the fog-cool season,relative humidity(R2≥38%)in the hot-dry season,and vapor pressure deficit(R2≥13%)in the rainy season.The persistent drought in 2020 weakened the regulatory effects of photosynthetically active radiation(R2=22%),vapor pressure deficit(R2=28%)and relative humidity(R2=33%)on sap flow density during the hot-dry season.(3)Under drought stress in 2020,the sensi-tivity(absolute slope values)of sap flow density to relative humidity and vapor pressure deficit decreased significantly,with values of 0.81±0.17 and 0.24±0.09,equivalent to only 52%and 55%of the values in 2021,and 47%and 36%of those in 2022,respectively.Meanwhile,the optimal relative humidity threshold for sap flow density declined significantly from 63%-65%in non-drought years to approximately 40%in the drought year,whereas the optimal vapor pressure deficit threshold increased significantly from 0.52-0.64 kPa to around 1.04 kPa(P<0.05).关键词
液流密度/热扩散探针/环境因子/干旱/敏感性/阈值Key words
Sap flow density/Thermal dissipation probe/Environmental factors/Drought/Sensitivity/Threshold分类
农业科技引用本文复制引用
李玉萌,王传华,林友兴,张家凤,黄雄,林华,范泽鑫,付培立,罗艳,吴宇,吕坤..干旱对西双版纳望天树液流密度的影响[J].东北林业大学学报,2026,54(10):72-82,11.基金项目
国家自然科学基金项目(32001168) （32001168）
云南省基础研究计划项目青年项目(202001AU070131). （202001AU070131）
