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Root exudates are a labile source of carbon (C) for microorganisms that can lead to increased CO2 emission. Root exudates can vary in C:N stoichiometric ratio and their impact on microbially driven soil organic matter (SOM) turnover in paddy soils still remains unclear. The objective was to explore the underlying mechanisms involved in SOM decomposition due to root exudate (artificial) addition wi
Rice paddy agro-ecosystems play an important role in global carbon (C) sequestration. Because of flooding management, paddy soil experience periodical changes in oxygen availability, which may make soil organic carbon (SOC) mineralisation unique as compared to upland or other wetland ecosystems. However, at present, information about the relevant mechanisms involved in paddy SOC mineralisation is
In this work, the forestry-enabled dynamic vegetation model LPJ-GUESS was used to simulate forest standing volume for the three main regions of Sweden. At the regional scale, the model results were evaluated against observational data from the Swedish National Forest Inventory. Carbon fluxes of net ecosystem exchange (NEE), gross primary productivity (GPP), and ecosystem respiration (Reco) were si
In this study we introduce a novel extension of an existing Lagrangian particle dispersion model for application over urban areas by explicitly taking into account the urban canopy layer. As commonly done, the original model uses the zero-plane displacement as a lower boundary condition, while the extension reaches to the ground. To achieve this, spatially-averaged parametrizations of flow and tur
Under de senaste åren har ord som krig, kris och råvarubrist varit hett nyhetsstoff. Pandemin och Rysslands krig i Ukraina har visat hur sammanlänkade vi är i en global ekonomi. Men redan på 1800-talet, mitt under brinnande inbördeskrig i USA, drabbades världen av sin första globala råvarukris. ”Bomullskrisen” orsakades av en exportblockad av bomull från de amerikanska sydstaterna och påverkade EuUnder de senaste åren har ord som krig, kris och råvarubrist varit hett nyhetsstoff. Pandemin och Rysslands krig i Ukraina har visat hur sammanlänkade vi är i en global ekonomi. Men redan på 1800-talet, mitt under brinnande inbördeskrig i USA, drabbades världen av sin första globala råvarukris. ”Bomullskrisen” orsakades av en exportblockad av bomull från de amerikanska sydstaterna och påverkade Eu
The mechanisms leading to the occurrence of extreme weather and climate events are varied and complex. They generally encompass a combination of dynamic and thermodynamic processes, as well as drivers external to the climate system, such as anthropogenic greenhouse gas emissions and land use change. Here we present the ExtremeX multi-model intercomparison experiment, which was designed to investig
Soil organic matter (SOM) decomposition in response to global change represents a critical uncertainty in coupled carbon (C) cycle-climate models. Much of this uncertainty arises from our limited mechanistic knowledge of the effects of organic C input frequency on SOM decomposition. Based on a three-source-partitioning isotopic approach (14C glucose addition to soil continuously labeled by C4 plan
Peatland ecosystems emit biogenic volatile organic compounds (BVOC), which have a net cooling impact on the climate. However, the quality and quantity of BVOC emissions, and how they are regulated by vegetation and peatland type remain poorly understood. Here we measured BVOC emissions with dynamic enclosures from two major boreal peatland types, a minerotrophic fen and an ombrotrophic bog situate
Large-scale photovoltaic solar farms envisioned over the Sahara desert can meet the world's energy demand while increasing regional rainfall and vegetation cover. However, adverse remote effects resulting from atmospheric teleconnections could offset such regional benefits. We use state-of-the-art Earth-system model simulations to evaluate the global impacts of Sahara solar farms. Our results indi
Field-based thermal infrared cameras provide surface temperature information at very high spatial and temporal resolution and could complement existing phenological camera and spectral sensor networks. Since temperature is one of the main drivers of ecosystem respiration (ER), field-based thermal cameras offer a new opportunity to model and upscale ER in unprecedented detail. We present such an ap
Boreal forests and peatlands are globally significant carbon stores but they are threatened by rising air temperatures and changes in precipitation regimes and the frequency of natural disturbances. Predicting how the boreal biome will respond to climate change depends on being able to accurately model and upscale the greenhouse gas fluxes between these ecosystems and the atmosphere. This thesis f
Labile carbon (C) inputs affect the soil carbon:nitrogen (C:N) ratio and microbial stoichiometric homeostasis, which control the intensity and direction of the priming effect (PE). Here, we clarified how soil microorganisms regulate enzyme production and PE to maintain the C:N stoichiometric balance. Specifically, we conducted an incubation experiment by adding 13C-labeled glucose to four long-ter
Estimates of land-atmosphere exchanges of carbon, energy, water vapor, and other greenhouse gases based on the eddy covariance (EC) technique rely on the fundamental assumption that the flux footprint area is homogeneous. We investigated the impact of source area heterogeneity on flux estimates in single-level EC measurements over a managed boreal forest landscape. For this purpose, we compared si
Mangrove plantations are crucial for carbon sequestration in global climate change mitigation efforts. However, the dynamics and partitioning of carbon stocks in the soil vegetation system in mangrove plantations are little understood. We assessed the carbon stocks across different plantation age groups, species, and sites. Our findings revealed that soil C concentration ranged from 0.4 to 1.5%, a
The Intergovernmental Panel on Climate Change (IPCC) maintains a fine balance between scientific credibility and policy-relevance. The IPCC's review process plays an important role in ensuring that this takes place. This paper looks at the review process of the Summary for Policymakers of the Special Report on Global Warming of 1.5 Degrees (SR15) published in 2018. We apply a framework for the mak
Resolving challenges related to the sustainability of natural capital and ecosystem services is an urgent issue. No roadmap on reaching sustainability exists; and the kind of sustainable land use required in a world that acknowledges both multiple environmental boundaries and local human well-being presents a quandary. In this commentary, we argue that a new globally consistent and expandable syst
Accumulated carbon uptake, apparent quantum yield (AQY) and light-saturated net CO2 assimilation (A(sat)) were used to assess the responses of photosynthesis to environmental conditions during spring for three consecutive years. Whole-tree chambers were used to expose 40-year-old field-grown Norway spruce trees in northern Sweden to an elevated atmospheric CO2 concentration, [CO2], of 700 mu mol C
Bioenergy plays a major role in the renewable energy supply and is projected to be an important part of the path towards a decarbonised society. Over the past decade, increasing attention has been given to agricultural bioenergy to act as a multifunctional climate mitigation strategy. Energy crops may mitigate climate change while simultaneously contributing to reducing the negative environmental
