摘要
【目的】研究内蒙古大兴安岭兴安落叶松Larix gmelini林生长季蒸散量(ET)变化特征,同时分析气象因子在不同天气状况下对兴安落叶松林蒸散量的影响以及不同时间尺度下气象因子对蒸散量的影响。【方法】以兴安落叶松林为研究对象,利用涡度相关系统对其生长季蒸散量(ET)以及空气温度、相对湿度、风速、光合有效辐射、净辐射、降水量进行测定,并用Pearson法、主成分分析(PCA)以及多元回归拟合的方法对蒸散与各气象因子进行相关性分析。【结果】在非降雨日兴安落叶松林生长季蒸散量的日内变化呈钟型分布,在生长旺盛期达到最大,峰值为0.28 mm·h^(-1)。不同天气条件下,兴安落叶松林生长季蒸散量(ET)日变化波动幅度差异较大,降水后蒸散量显著升高。影响6月份蒸散量的气象因子为风速(S_(w))、净辐射量(R_(n))、水汽压亏缺(VPD),影响7月份蒸散量的气象因子主要为空气温度(T)和光合有效辐射(PAR)。不同时间尺度下各气象因子与蒸散量的相关性差异不大,其中相对湿度在日尺度和小时尺度下都与蒸散量呈负相关,相关系数为-0.140、-0.473。不同时间尺度下各气象因子与蒸散量的多元线性拟合度为:日尺度,R^(2)=0.73;小时尺度,R^(2)=0.56。【结论】净辐射量、光合有效辐射、空气温度、水汽压亏缺是决定植被用水和大气边界层水传输的主要气象动力,是影响兴安落叶松林蒸散量的主要气象因子。
【Objective】To study the variation characteristics of evapotranspiration(ET)of Larix gmelini forest in Daxing'an mountains of Inner Mongolia,and analyze the influence of meteorological factors on the evapotranspiration of Larix gmelini forest under different weather conditions and different time scales.【Method】Taking Larix gmelinii forest as the research object,the evapotranspiration(ET),air temperature,relative humidity,wind speed,photosynthetically active radiation,net radiation and rainfall in growing season were measured by vorticity correlation system.The correlation between evapotranspiration and meteorological factors was analyzed by Pearson method,principal component analysis(PCA)and multiple regression fitting methods.【Result】The diurnal variation of evapotranspiration of Larix gmelinii forest in the growing season showed a bell shaped distribution on non-rainfall days,and reached the maximum in the vigorous growth period,with a peak value of 0.28 mm·h^(-1).Under different weather conditions,the diurnal variation of evapotranspiration(ET)of Larix gmelinii forest in growing season was different,and the evapotranspiration increased significantly after precipitation.The meteorological factors affecting evapotranspiration in June are wind speed(SW),net radiation(R_(n))and water vapor pressure deficit(VPD).The main meteorological factors affecting evapotranspiration in July are air temperature(T)and photosynthetic effective radiation(PAR).The correlation coefficients of relative humidity and evapotranspiration were-0.140,-0.473.Under different time scales,the multiple linear fitting degree of each meteorological factor and evapotranspiration is:Daily scale(R^(2)=0.73),hourly scale(R^(2)=0.56).【Conclusion】Net radiation,photosynthetically active radiation,air temperature and water vapor pressure deficit are the main meteorological factors that determine vegetation water use and atmospheric boundary layer water transport,and are the main meteorological factors affecting the evapotranspiration of
作者
刘浩
张秋良
LIU Hao;ZHANG Qiuliang(College of Forestry,Inner Mongolia Agricultural University,Hohhot 010010,Inner Mongolia,China)
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2021年第3期149-156,共8页
Journal of Central South University of Forestry & Technology
基金
内蒙古自治区自然科学基金项目(2018MS03049)。
关键词
兴安落叶松
生长季
蒸散
涡度相关
Larix gmelinii
growing season
evapotranspiration
vorticity correlation
