北京低山区典型人工林树干液流对土壤水分胁迫的响应  

Response of tree stem sap to soil moisture stress in typical plantations in the low mountainous area of Beijing

作　　者：高连炜 马子澳 刘春和 赵莉丽 王奥 查同刚[1] GAO Lianwei;MA Ziao;LIU Chunhe;ZHAO Lili;WANG Ao;ZHA Tonggang(School of Soil and Water Conservation,Beijing Forestry University,100083,Beijing,China;Badaling Forest Farm,102112,Beijing,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]北京市八达岭林场,北京102112

出　　处：《中国水土保持科学》2024年第4期129-136,共8页Science of Soil and Water Conservation

基　　金：国家林业和草原局林业科学技术推广项目“北京八达岭林场水分高效利用的森林经营管理技术推广示范”(201903)。

摘　　要：树干液流在不同土壤水分胁迫下的变化规律和对气象因子的响应机制,是了解树木适应环境变化机制和林分水分循环机制的重要内容。以北京低山区典型造林树种元宝枫、油松为研究对象,采用热扩散探针技术监测树干液流年度变化,探究不同土壤水分条件下树干液流密度变化规律及其驱动因素。结果表明:1)元宝枫和油松树干液流密度均呈现“单峰”型年度变化,2022年存在土壤水分胁迫的时间占全年的76.2%;2)元宝枫和油松树干液流密度均随水分胁迫程度加剧而显著减小(P<0.05);土壤相对含水量在水分胁迫时对单位饱和水汽压差的树干液流密度影响显著(P<0.05),在无水分胁迫时影响不显著,重度水分胁迫条件下,土壤相对含水量对元宝枫和油松单位饱和水汽压差的树干液流密度的解释率分别为62.2%和54.3%;3)多元逐步回归分析表明,无水分胁迫时,树干液流密度主导因素为气象因子,轻微水分胁迫时,树干液流密度受气象因子和土壤水分共同制约,重度水分胁迫时土壤水分成为唯一主导因素。本研究阐明了北京低山地区典型人工林树干液流对土壤水分条件的响应规律,结果可为该区域人工林抚育管理提供技术指导。[Background]Drought and water shortage are important factors limiting the ecological construction in North China.Soil moisture is an important factor affecting tree stem sap,which determines the overall level of tree stem sap and its response sensitivity to environmental factors.The main factors of tree stem sap are different under different soil moisture conditions.The variations of tree stem sap and the response mechanism to meteorological factors under different soil moisture stress are important contents of understanding the adaptation mechanism of trees to environmental change and the water cycle mechanism.[Methods]The representative plots of Acer truncatum and Pinus tabuliformis,two typical tree species in the low mountainous area of Beijing were selected.The thermal diffusion probe technique was used to monitor the yearly change of tree stem sap density of A.truncatum and P.tabuliformis.The time domain reflect system was set up in two plots to monitor soil moisture.The automatic weather station was used to monitor weather factors in real time.The tree stem sap density and environmental factors under different soil water stress were analyzed by regression analysis.The yearly change of tree stem sap density and its driving factors under different soil moisture conditions were investigated.[Results]1)The tree stem sap density of A.truncatum and P.tabuliformis demonstrated“unimodal”type yearly changes,and the number of days with soil moisture stress in 2022 accounted for 76.2%of the whole year.2)The tree stem sap density of both A.truncatum and P.tabuliformis decreased significantly with the increase of moisture stress(P<0.05).Soil relative water content had a substantial influence on tree stem sap density per unit of vapor pressure deficit(VPD)under soil moisture stress(P<0.05),but not under no soil moisture stress.Under severe soil moisture stress,soil relative water content explained 62.2%and 54.3%of tree stem sap density per unit of VPD of A.truncatum and P.tabuliformis.3)Multiple stepwise regression a

关 键 词：树干液流 气象因子 土壤水分胁迫 元宝枫 油松 

分 类 号：S715.4[农业科学—林学]