摘要
【目的】通过对油松生长季夜间液流特征和环境驱动因素的研究,揭示夜间液流组分拆分特征,探讨夜间液流的组分与气象因子之间的相关关系,以及茎干补水对气象因子的响应,为华北土石山区水资源和水源涵养林管理决策提供理论依据。【方法】以华北土石山区的油松作为研究对象,根据径阶大小选取18棵样树,在2014年生长季运用Granier热扩散探针技术(TDP)持续观测夜间液流,结合称重式蒸渗仪和自制微型蒸渗仪来计算蒸腾量,解析夜间液流的去向;并进行夜间液流与土壤含水量、大气温度、湿度及光合有效辐射等气象因子的相关分析,以确定主要驱动因素。【结果】在6—9月典型晴天,夜间液流速率都呈逐渐降低趋势,18:00—24:00的夜间液流速率高于00:00—05:00,夜间液流主要用于对白天失水过多的茎干进行补水,以至于在24:00时油松茎干储水量基本达到饱和,因此,00:00—05:00夜间液流速率趋于稳定;油松夜间液流用于茎干补水的比例(95.34%)显著高于用于夜间蒸腾量的比例(4.66%);油松夜间茎干补水量与饱和水汽压差呈极显著正相关(R^(2)=0.793,P<0.01),而对土壤含水量变化响应不敏感(R^(2)=0.105,P>0.05),表明夜间液流主要受饱和水汽压影响。【结论】华北土石山区的油松生长季夜间液流随着夜间时间的进行呈现逐渐降低的趋势;绝大部分的夜间液流用于夜间茎干补水,在气象因子中,饱和水汽压是驱动夜间茎干补水及夜间液流的重要因子(P<0.01)。
【Objective】By studying the characteristics of nocturnal sap flow and environmental driving factors in Pinus tabuliformis during the growing season,to reveal the characteristics of nocturnal sap flow component splitting,to discuss the correlation between components of nocturnal sap flow and meteorological factors,as well as the response of stem refilling to meteorological factors,and provide theoretical basis for the management decision of water resources and water-source conservation forests in rocky mountain area of North China.【Method】Taking P.tabuliformis in rocky mountain area of North China as the research objection,18 sample trees were selected according to the diameter size,using Granier Thermal Dispersion Probe(TDP)technique to continuously observe nocturnal sap flow during the growing season of 2014,combined with the weighing lysimeter meter and homemade micro-evapotranspiration meter to calculate the evapotranspiration and to resolve the destination of nocturnal sap flow;and to correlate nocturnal sap flow with meteorological factors such as soil water content,atmospheric temperature,humidity and photosynthetically active radiation to determine the main driving factors.【Result】The results showed that:the nocturnal sap flow velocity gradually decreased on typical sunny days in June,July,August,and September,and was higher from 18:00 to 24:00 than from 00:00 to 05:00.The nocturnal sap flow was mainly used to refill the stem that had lost too much water during the day,so that the storage capacity of the stem of P.tabuliformis basically reached saturation by 24:00,so the nocturnal sap flow velocity tended to stabilize between 00:00 and 05:00.The proportion of nocturnal sap flow used for stem refilling(95.34%)was significantly higher than that used for nocturnal transpiration(4.66%),nocturnal stem refilling of P.tabuliformis was highly significantly positively correlated with vapor pressure deficit(R^(2)=0.793,P<0.01),while it was almost insensitive to soil water content(R^(2)=0.105,P>0.05),indicating that nocturnal sap flow was mainly influenced by vapor pressure deficit.【Conclusion】Nocturnal sap flow during the growing season of P.tabuliformis in rocky mountain area of North China showed a gradual decrease over time.The vast majority of nocturnal sap flow was used for nocturnal stem refill,and among the meteorological factors,vapor pressure deficit was the main factor driving nocturnal stem refill and nocturnal sap flow(P<0.01).
作者
胡蕾
贾剑波
闫文德
王一帆
吴瑞乔
陈玉
Hu Lei;Jia Jianbo;Yan Wende;Wang Yifan;Wu Ruiqiao;Chen Yu(Central South University of Forestry&Technology,Changsha 410004;Hunan Lutou Forest Ecosystem National Orientation Observation and Research Station,Yueyang 414000;National Engineering Laboratory of Applied Technology for Forestry&Ecology in Southern China,Changsha 410004)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2024年第4期91-98,共8页
Scientia Silvae Sinicae
基金
湖南省重点领域研发计划项目(2023SK2055)
湖南省自然科学基金面上项目(2023JJ31003)。
关键词
夜间液流
分配特征
茎干补水
夜间蒸腾
华北土石山区
nocturnal sap flow
distribution characteristics
stem refilling
nocturnal transpiration
in rocky mountain area of North China
作者简介
通讯作者:贾剑波。
