林业与生态科学2025，Vol.40Issue(2)：127-135,9.DOI:10.13320/j.cnki.hjfor.2025.0015
冀西北坝上地区白榆光合生理特征及其影响因素研究
Photosynthetic physiological characteristics and influencing factors of Ulmus pumila in Bashang area of northwest Hebei Province
摘要
Abstract
In order to explore the photosynthetic physiological characteristics of Ulmus pumi-la in Bashang area of northwest Hebei Province,the main physiological and ecological factors affecting the photosynthesis of Ulmus pumila were determined.In this study,the artificial pure forest of Ulmus pumila was taken as the research object,and the lI-6400XT portable photosynthesis analyzer was used to measure the photosynthetic physiological indexes of Ul-mus pumila leaves under natural light.The meteorological factors were measured in field ob-servation,and the diurnal variation law of soil water content(SWC)was determined by TDR.The effects of physiological and ecological factors on photosynthetic water physiologi-cal indexes ofUlmus pumila were analyzed.The results showed that:(1)From 6:00 to 18:00,the diurnal variation trends of net photosynthetic rate(Pn),stomatal conductance(Gs),transpiration rate(Tr),and stomatal limit value(Ls)of Ulmus pumila presented a"uni-modal"curve of increasing first and then decreasing,while the diurnal variation trends of in-tercellular carbon dioxid(Ci)presented a"valley—type"curve of decreasing first and then increasing,and the daily variation of water use efficiency(WUE)showed a decreasing trend.(2)The diurnal variation of Ulmus pumila Pn was limited by both stomatal restriction and non-stomatal restriction.Pn was limited by non-stomatal restriction from 8:00 to 14:00 and stomatal restriction at other periods.(3)Pn of Ulmus pumila was positively correlated with Gs and air humidity(RH)(P＜0.01),and negatively correlated with differential vapor pres-sure at blade saturation(VPD)and SWC of 100-150 cm.Besides,Pn was positively corre-lated with SWC of 0-20 cm(P＜0.05)and negatively correlated with SWC of 40-70 cm.(4)The roots system of Ulmus pumila were distributed in 0-200 cm soil layer,but mainly appeared in shallow layer.The biomass of fine roots was mainly concentrated in 0-20 cm soil layer,and the coarse roots were mainly distributed in 20-40 cm soil layer.In conclu-sion,the diurnal variation of photosynthesis of Ulmus pumila in Bashang area of northwest Hebei Province is mainly affected by Gs,RH and SWC,and is consistent with the variation of surface soil water.关键词
白榆/冀西北坝上地区/光合生理特性/环境因子/根系分布Key words
Ulmus pumila/Bashang area of northwest Hebei Province/photosynthetic physi-ological characteristics/environmental factors/root distribution分类
农业科技引用本文复制引用
魏可新,朱琪,李阳,李晓刚,马增旺,李玉灵..冀西北坝上地区白榆光合生理特征及其影响因素研究[J].林业与生态科学,2025,40(2):127-135,9.基金项目
河北省省级科技计划资助项目(22326808D) （22326808D）
河北省林草关键技术创新与示范项目(2301085) （2301085）
河北省林业和草原科技推广示范项目(冀TG[2022]016号). （冀TG[2022]016号）
