Phenology controls on CO2 exchange in a northern peatland: insights from a decade-long record of phenocam imagery and eddy-covariance data

• DOI: 10.5194/egusphere-egu24-14977
• Publication Date: 2024-03-09T02:09:04Z
• Authors: Gillian Simpson; Järvi Järveoja; Mats Nilsson; Matthias Peichl

Northern peatlands are recognised as important long-term carbon sinks. However, measurements from a number of peatland sites reveal large amount interannual variability in their net dioxide (CO2) balance. Differences both weather conditions and plant phenology (i.e. the seasonal development vegetation canopy) between years thought to be key here. Timing growing season start, end, length) regulates period over which can actively photosynthesise. Hence, longer is often related increased CO2 uptake for example. At same time, meteorological (e.g. air temperature, water-table depth) affect not only physiology, but also its phenological cycle. Our current understanding complex interplay these two main drivers dynamics has been limited by lack studies. This work explores unique, decade-long record phenocam eddy-covariance data Degerö Stormyr, northern Swedish peatland. We used structural equation modelling (SEM) identify pathways regulating uptake, found that plays an ‘mediator’ role season. analysis further suggest increases greenness linked These findings provide valuable insight on controls dynamics, feedbacks with future climate change.