小兴安岭位于中国东北部的温带季风气候区，以针阔叶混交林为主，拥有亚洲最大、最完整的红松原始森林，对区域气候有重要的调控作用。为探究小兴安岭针阔叶混交林感热通量（H）和潜热通量（LE）特征，以及环境、生物因子对其的调控作用，采用涡度相关法对五营国家气候观象台 2007-2023 年 H 和 LE 进行研究，并构建结构方程模型对其影响因子进行详细分析。结果表明：小兴安岭针阔叶混交林 H 和 LE 的年际变化有波动减少趋势，但二者变化趋势不完全相同，40 m 高度处的 H 和 LE年平均值分别为 19. 84±1. 83 W·m-2 和 29. 39±2. 93 W·m-2，50 m 高度处的 H 和 LE 年平均值分别为22. 71±1. 29 W·m-2和31. 76±1. 07 W·m-2。H的峰值出现在4月，次峰值出现在10月，而LE的峰值出现在 7 月，其中 5-9 月 LE 大于 H，说明有效能量的分配在 5-9 月以潜热为主，其他月份以感热为主。30 min 尺度能量闭合率为 49%，各月能量闭合率范围为 32%~61%，其中生长季和非生长季分别为 53%和38%，日尺度能量闭合率为52%。结构方程模型显示，小兴安岭针阔叶混交林的热量传输过程主要受能量限制，净辐射对H和LE有正影响，空气温度、饱和水气压差、土壤体积含水量、叶面积指数对H和LE 的影响均是相反的。气候变化对 H 和 LE 有复杂的调控机制，对不同气候年份分别构建结构方程模型，可以对H和LE复杂年际变化做出部分解释。

Located in the temperate monsoon climate zone of northeast China，dominated by coniferous and broad-leaved mixed forest the Lesser Khingan Mountains has the largest and most complete primary forest of Korean pine in Asia，which plays an important role in regulating the regional climate. In order to explore the sensible heat flux（H）and latent heat flux（LE）characteristics of the coniferous and broad-leaved mixed forest in the Lesser Khingan Mountains and the regulation effect of environmental，biological factors on H and LE，H and LE at 40 m and 50 m altitude of Wuying National Climate Observatory from 2007 to 2023 were studied by using the eddy correlation method，and a structural equation model was constructed to analyze the influencing factors in detail. The results show that：The interannual variation of H and LE in the coniferous and broad-leaved mixed forest in the Lesser Khingan Mountains showed a decreasing trend，but the variation trend was not completely consistent. The annual average of H and LE at 40 m height was 19. 84±1. 83 W·m-2 and 29. 39±2. 93 W·m-2，re‐ spectively. The annual average of H and LE at 50 m altitude was 22. 71±1. 29 W·m-2 and 31. 76±1. 07 W·m-2，re‐ spectively. The peak of H appeared in April，the secondary peak in October，and the peak of LE appeared in Ju‐ ly，in which LE was greater than H from May to September，indicating that the energy conversion was dominat‐ ed by latent heat exchange in May to September，and by sensible heat exchange in other months. The 30-min scale energy closure rate was 49%，the monthly energy closure rate ranged from 32 to 61%，in which the grow‐ ing season and non-growing season were 53% and 38%，respectively，and the daily scale energy closure rate was 52%. The structural equation model showed that the heat transfer process of the coniferous and broad-leaved mixed forest in the Lesser Khingan Mountains was mainly limited by energy. Net radiation had a positive effect on H and LE，while air temperature，vapor pressure deficit，soil volumetric water content and leaf area index had opposite effects on H and LE. Climate change has a complex regulatory mechanism on H and LE. The com‐ plex interannual variation of H and LE can be partially explained by constructing structural equation models for different years.