文献类型：期刊文献

中文题名：雷州半岛桉树人工林生态系统水分利用效率旱雨季差异及其控制因素

英文题名：Differences in water use efficiency between dry and rainy seasons and their controlling factors in Eucalyptus plantation in Leizhou Peninsula

作者：竹万宽[1] 许宇星[1] 黄润霞[1] 杜阿朋[1] 王志超[1]

第一作者：竹万宽

机构：[1]中国林业科学研究院速生树木研究所,广东湛江桉树林生态系统定位观测研究站,广东湛江524022

年份：2025

卷号：49

期号：12

起止页码：2015-2029

中文期刊名：植物生态学报

外文期刊名：Chinese Journal of Plant Ecology

收录：;北大核心:【北大核心2023】；

基金：国家重点研发计划(2023YFD2201005)。

语种：中文

中文关键词：桉树人工林;涡度相关;水分利用效率;生物环境因子

外文关键词：Eucalyptus plantation;eddy covariance;water use efficiency;biological environmental factor

分类号：S718.55

摘要：研究人工林生态系统水分利用效率(WUE)对环境因子的响应,对于揭示植被的水分利用策略及评估生态系统碳水循环能力具有重要意义。该研究基于广东湛江桉树林生态系统定位观测研究站2018-2022年涡度相关通量数据及同步气象观测数据,采用逐步回归分析、路径分析和冗余分析方法,分析尾叶桉(Eucalyptus urophylla)人工林生态系统WUE的时间变化及季节性差异特征,研究WUE与生物环境因子的关系,探讨WUE旱、雨季差异及其主要影响因素。主要结果:(1)观测期间尾叶桉人工林生态系统旱季(11-4月)和雨季(5-10月)WUE平均值分别为3.85和2.61 g C·kg^(-1) H_(2)O,WUE全年平均值为3.22 g C·kg^(-1)H_(2)O。(2)WUE具有明显的日间变化特征,旱季和雨季变化趋势相似。日间WUE与饱和水汽压差(VPD)、空气温度(T_(air))、土壤温度(T_(soil))、光合有效辐射(PAR)及土壤湿度(SM)均存在极显著负相关关系,逐步回归分析表明VPD是调控WUE日间变化的主要环境因子。(3)日均值尺度WUE的变化趋势与总初级生产力(GPP)和蒸散(ET)相反,路径分析表明WUE主要受到VPD和T_(soil)的直接负面影响,以及PAR的间接负面影响。WUE对VPD、T_(soil)变化的响应存在明显旱、雨季差异,对PAR变化的季节响应类似。(4)在月均值尺度上,旱季WUE主要受温度和VPD影响,雨季WUE主要受到PAR影响,WUE的季节差异由温度、VPD和PAR调控下ET的变化主导。桉树人工林生态系统WUE旱季高于雨季,日间变化主要受VPD影响,日、月变化除受到VPD影响外,还受到光照和温度的影响。
Aims Examining how water use efficiency(WUE)in plantations responds to environmental factors is crucial for understanding vegetation’s water strategies and assessing ecosystems’carbon and water recycling capacity.Methods In the present study,we leveraged eddy covariance flux data alongside concurrent meteorological data from the Positioning Observation and Research Station of Eucalyptus Plantation Ecosystem,spanning the years 2018 to 2022,to analyze the temporal variations and seasonal differences in WUE within the Eucalyptus plantation ecosystem.The analytical methods employed included stepwise regression analysis,path analysis,and redundancy analysis.We analytically examined the relationship between WUE and various environmental factors,with a particular focus on the distinctions between drought and rainy seasons,as well as the primary factors influencing these variations.Important findings(1)Throughout the study period,the mean WUE of the Eucalyptus plantation ecosystem was recorded at 3.85 g C·kg^(-1)H_(2)O during the dry season(November to April)and 2.61 g C·kg^(-1)H_(2)O during the rainy season(May to October).The annual mean WUE was determined to be 3.22 g C·kg^(-1)H_(2)O.(2)WUE exhibited distinct diurnal variation patterns,with similar trends observed during both the dry and rainy seasons.A extremely significant negative correlation was identified between diurnal WUE and variables such as vapor pressure deficit(VPD),air temperature(Tair),soil temperature(T_(soil)),photosynthetically active radiation(PAR),and soil moisture(SM).Furthermore,stepwise regression analysis indicated that VPD serves as the primary environmental factor influencing the diurnal variation of WUE.(3)The temporal variation of daily-scale WUE exhibited an inverse relationship with gross primary productivity(GPP)and evapotranspiration(ET).Path analysis indicated that WUE is predominantly influenced by direct negative impacts from VPD and T_(soil),in addition to indirect negative influences from PAR.The responses of WUE to VPD and T_(soil) demonstrated significant discrepancies between dry and rainy seasons,while the seasonal responses to PAR were found to be consistent.(4)On a monthly basis,WUE was predominantly influenced by temperature and VPD during the dry season,while PAR played a significant role in the rainy season.The variations in WUE across different seasons were primarily influenced by alterations in ET,which were governed by temperature,VPD,and PAR.The WUE of the Eucalyptus plantation ecosystem exhibited marked variations between the drought and rainy seasons,and the diurnal changes were mainly affected by VPD.In addition to being affected by VPD,the daily and monthly changes are also affected by light and temperature.