The role of non-growing season emissions of greenhouse gases in annual budgets along a moisture gradient in boreal Finland

Abstract:

Emissions of greenhouse gases, including CO₂, CH₄, and N₂O, are poorly quantified on an annual time scale in northern high latitude ecosystems, including boreal wetlands and forests. Emissions outside of the growing season are particularly poorly understood because most measurements in these cold ecosystems have been made during the summer growing season. However, recent studies have shown that shoulder season and winter emissions can contribute significantly to annual greenhouse gas emissions. This new ERC-funded research project FluxWIN focuses on how carbon and nitrogen cycling and resulting greenhouse gas emissions change between the growing season, when plants and scientists are active, and outside of the growing season, when plants are not active and many fewer measurements are collected. Here, we investigate emissions of these greenhouse gases throughout the year across several different northern ecosystem types at a boreal site in Finland spanning wetlands and upland forest. We use automated chambers and high frequency greenhouse gas flux measurements as well as modeling and experiments to understand the underlying processes resulting in greenhouse gas emissions. These results will help to improve process-based models of greenhouse gas emissions and local and regional scale emissions budgets.