The timescale dependence of environmental factors’ influence on net ecosystem productivity (NEP), evapotranspiration (ET), and the effect of high and cool air temperature (Ta) across multiple timescales need to be quantified to identify the response mechanisms of forest ecosystems. We analyzed NEP and ET over 11 years in a subtropical coniferous plantation, and wavelet analysis was used to determine spectrum characteristics of these fluxes and quantify the time lag between these fluxes and environmental factors from daily to annual timescales. The NEP and ET had significant daily and annual spectrum variabilities, but ET exhibited a broader significant spectrum than NEP from days to months timescales. At daily and annual timescales, NEP was significantly synchronized with, and preceded photosynthetically active radiation (PAR) and Ta by 1. 12 ± 0.6 h and 23.16 ± 17 days, respectively. Meanwhile, ET was significantly synchronized with net radiation (Rn) at both daily and annual timescales, lagging Rn by 1.15 ± 1.4 h, but preceding it by 5. 73 ± 4.39 days, respectively. From days to months timescales, with no continuous significant effect, NEP preceded PAR and vapor pressure deficit (VPD), and lagged soil water content (SW); however, ET only preceded Rn and VPD. In addition, summer high-Ta enhanced the effect of SW on NEP and ET across multiple timescales. Early spring cool-Ta shortened the time lag between PAR and NEP at daily and annual timescales, but only shortened it between Ta and ET at a daily timescale. This study demonstrated the more modulating effect of SW on the dominant influence of solar energy on NEP than ET, with timescale increased. This study also indicated that NEP and ET were more sensitive to high- than cool-Ta, and the time lag effects of these Ta events should be considered separately to adequately acknowledge the response mechanisms of these fluxes.

需要量化环境因素在时间尺度上对净生态系统生产力（NEP），蒸散量（ET）的影响以及跨多个时间尺度的高温和低温空气（Ta）的影响，以确定森林生态系统的响应机制。我们在亚热带针叶人工林中分析了11年的NEP和ET，并使用小波分析来确定这些通量的频谱特征，并量化了这些通量与环境因素之间从每天到每年的时间尺度之间的时滞。NEP和ET在每日和每年的频谱上都有很大的变化，但是从几天到几个月的时间尺度，ET表现出比NEP更大的重要频谱。在每日和每年的时间尺度上，NEP与光合有效辐射（PAR）和Ta显着同步，并且先于1. 12±0。6小时和23.16±17天。同时，在每天和每年的时间尺度上，ET都与净辐射（Rn）显着同步，分别比Rn落后1.15±1.4 h，但比其提前了5. 73±4.39天。从几天到几个月的时间尺度，没有连续的显着影响，NEP早于PAR和蒸气压亏空（VPD）以及滞后的土壤含水量（SW）；但是，ET仅在Rn和VPD之前。此外，夏季高Ta在多个时间尺度上都增强了SW对NEP和ET的影响。早春凉爽的Ta缩短了每日和年度时间尺度的PAR和NEP之间的时滞，但仅缩短了Ta和ET的时间尺度。这项研究表明，随着时间的增加，SW对NEP的太阳能主导作用比ET更具调节作用。