Continuous Measurement of Canopy Fluorescence at Harvard Forest since 2013

Vegetation fluorescence, a very small amount of radiation emitted as a byproduct of photosynthesis, is a direct indicator of plant physiology. Monitoring the solar-induced plant fluorescence provides a powerful tool to understand how the plant photosynthesis responds to environmental factors such as solar radiation, temperature and precipitation as well as to stress and disturbance. We installed the ground-based fluorescence observation system to explore the Franhofer lines in the solar spectrum to monitor the canopy fluorescence. Fluorescence data could also be used to link with eddy covariance data in flux towers, the digital camera data and solar radiation data, providing a good supplementary to numerous data collected at HF.

植被荧光（Vegetation fluorescence）是光合作用副产物所释放的极微量辐射，是植物生理状态的直接指示指标。对太阳诱导型植物荧光开展监测，可为解析植物光合作用响应太阳辐射、温度、降水等环境因子以及胁迫与干扰的机制提供强有力的研究手段。本研究搭建了地基荧光观测系统，通过探测太阳光谱中的夫琅禾费谱线（Fraunhofer lines）以监测冠层荧光。荧光数据还可与通量塔的涡度协方差（eddy covariance）数据、数码相机观测数据以及太阳辐射数据进行关联分析，为高频（HF）采集的多类观测数据提供了优质的补充支撑。