High latitude mires are key ecosystems in the context of climate change since they store large amounts of carbon while constituting an important natural source of methane (CH 4 ). However, while a growing number of studies have investigated methane fluxes (FCH 4 ) at the plot‐ (~1 m 2 ) and ecosystem‐scale (~0.1–0.5 km 2 ) across the boreal biome, variations of FCH 4 magnitudes and drivers at the mesoscale (i.e., 0.5–20 km 2 )...

The extreme 2018 hot drought that affected central and northern Europe led to the worst wildfire season in Sweden in over a century. The Ljusdal fire complex, the largest area burnt that year (8995 ha), offered a rare opportunity to quantify the combined impacts of wildfire and post‐fire management on Scandinavian boreal forests. We present chamber measurements of soil CO 2 and CH 4 fluxes, soil microclimate and nutrient conte...

The boreal biome exchanges large amounts of carbon (C) and greenhouse gases (GHGs) with the atmosphere and thus significantly affects the global climate. A managed boreal landscape consists of various sinks and sources of carbon dioxide (CO 2 ), methane (CH 4 ), and dissolved organic and inorganic carbon (DOC and DIC) across forests, mires, lakes, and streams. Due to the spatial heterogeneity, large uncertainties exist regardi...

Aim The mechanisms of plant trait adaptation and acclimation are still poorly understood and, consequently, lack a consistent representation in terrestrial biosphere models (TBMs). Despite the increasing availability of geo‐referenced trait observations, current databases are still insufficient to cover all vegetation types and environmental conditions. In parallel, the growing number of continuous eddy‐covariance observations...

Earth observing systems are now routinely used to infer leaf area index ( LAI ) given its significance in spatial aggregation of land surface fluxes. Whether LAI is an appropriate scaling parameter for daytime growing season energy budget, surface conductance ( G s ), water‐ and light‐use efficiency and surface–atmosphere coupling of European boreal coniferous forests was explored using eddy‐covariance ( EC ) energy and CO 2 f...

In this study latent heat flux ( λE ) measurements made at 65 boreal and arctic eddy‐covariance ( EC ) sites were analyses by using the Penman–Monteith equation. Sites were stratified into nine different ecosystem types: harvested and burnt forest areas, pine forests, spruce or fir forests, Douglas‐fir forests, broadleaf deciduous forests, larch forests, wetlands, tundra and natural grasslands. The Penman–Monteith equation was...

The land‐atmosphere exchange of methane ( CH 4 ) and carbon dioxide ( CO 2 ) in a high‐ A rctic wet tundra ecosystem ( R ylekærene) in Z ackenberg, north‐eastern G reenland, was studied over the full growing season and until early winter in 2008 and from before snow melt until early winter in 2009. The eddy covariance technique was used to estimate CO 2 fluxes and a combination of the gradient and eddy covariance methods was u...

Many wetland ecosystems such as peatlands and wet tundra hold large amounts of organic carbon (C) in their soils, and are thus important in the terrestrial C cycle. We have synthesized data on the carbon dioxide (CO 2 ) exchange obtained from eddy covariance measurements from 12 wetland sites, covering 1–7 years at each site, across Europe and North America, ranging from ombrotrophic and minerotrophic peatlands to wet tundra e...

The intensification of the hydrological cycle, with an observed and modeled increase in drought incidence and severity, underscores the need to quantify drought effects on carbon cycling and the terrestrial sink. FLUXNET, a global network of eddy covariance towers, provides dense data streams of meteorological data, and through flux partitioning and gap filling algorithms, estimates of net ecosystem productivity ( F NEP ), gro...

Disturbance of ecosystems is a major factor in regional carbon budgets, and it is believed to be partly responsible for the large inter‐annual variability of the terrestrial part of the carbon balance. Forest fires have so far been considered as the most important disturbance but also other forms of disturbance such as insect outbreaks or wind‐throw might contribute significantly to the largely unexplained inter‐annual variabi...

Based on theories of mire development and responses to a changing climate, the current role of mires as a net carbon sink has been questioned. A rigorous evaluation of the current net C‐exchange in mires requires measurements of all relevant fluxes. Estimates of annual total carbon budgets in mires are still very limited. Here, we present a full carbon budget over 2 years for a boreal minerogenic oligotrophic mire in northern...

This paper develops a statistical model for daily gross primary production (GPP) in boreal and temperate coniferous forests. The model applies the light use efficiency (LUE) approach, which estimates the conversion efficiency of daily absorbed photosynthetically active radiation (APAR) into daily GPP as a product of potential LUE and modifying factors. The latter were derived from daily total APAR and daily mean temperature, v...

The timing of the commencement of photosynthesis ( P * ) in spring is an important determinant of growing‐season length and thus of the productivity of boreal forests. Although controlled experiments have shed light on environmental mechanisms triggering release from photoinhibition after winter, quantitative research for trees growing naturally in the field is scarce. In this study, we investigated the environmental cues init...