Fire is an essential feature of many ecosystems and an important component of the Earth system. Climate, vegetation, and human activity regulate fire occurrence and spread, but fires also feedback to them in multiple ways, resulting in changing fire regimes in many regions of the world. This session welcomes contributions that explore the role of fire in the Earth system at any temporal and spatial scale using modeling, field and laboratory observations, proxy-records including tree fire scars, sedimentary charcoal cores, ice cores, speleothems, and/or remote sensing. We encourage abstracts that advance our understanding on (1) fire related emissions (e.g. emission factors, emission height, smoke transport), (2) spatial and temporal changes of fire regimes in the past, present, and future, (3) fire products and models, and their validation, error/bias assessment and correction, (4) analytical tools designed to enhance situational awareness among fire practitioners and early warning systems. We are also welcoming submissions on fire related changes (5) in weather, climate, as well as atmospheric chemistry and circulation, (6) vegetation composition and structure, (7) cryosphere (e.g. permafrost, sea ice), (2) biogeochemical cycling of carbon, nitrogen and trace elements, (8) soil functioning and soil organic matter dynamics, as well as (9) effects of fires on humans (e.g., impact of fire on air and water quality, freshwater resources, human health, land use and land cover change, fire management).

Early career researchers and underrepresented groups in the field are strongly encouraged to apply.

Changes in cloud cover and emissions of natural and anthropogenic aerosols can significantly impact the biosphere through modifying climate (i.e., temperature, precipitation, quantity and quality of surface solar radiation), ozone production, nutrient deposition, etc. Meanwhile, the altered biosphere can further regulate the climate system by affecting mass and energy exchanges between the Earth's surface and the atmosphere through biophysical (altering surface albedo, evapotranspiration, etc.) and biochemical (changing carbon budget) processes. Clouds, aerosols, and interactions with the biosphere remain large sources of uncertainty in our understanding of the drivers of climate change. Thus, accurately describing these processes and feedbacks will help reduce uncertainties in climate projections, inform local to regional air quality control policies and better constrain the impacts of solar radiation modification strategies in geoengineering.

This session also highlights the interactions between tropospheric ozone and the vegetation. Ozone is a secondary pollutant and climate forcing agent. It is well-established that ozone damages vegetation (plant and crop) at concentrations observed in the present-day. This has the potential to change the land carbon budget and reduce crop yields, with further changes possible in the future. Therefore, in the context of climate change, it is essential to accurately measure ozone levels, its precursors, and study the ozone-vegetation interactions that influence the ecosystem carbon cycle.

This session aims to bring together researchers working on the interaction between the biosphere, clouds, aerosols and ozone. We welcome contributions from scientists investigating the mechanisms and quantifying the impacts of cloud-, aerosol- and ozone-induced changes on the biosphere, as well as their feedback to the climate system. We also welcome studies on solar radiation modification, especially those focusing on the biosphere. Studies across scales (local to global), over land or ocean and using various techniques (observational, experimental and modelling) are welcome.

Anthropogenic disturbance of the global nitrogen (N) cycle has more than doubled the amount of reactive N circulating in the terrestrial biosphere alone. Exchange of reactive/non-reactive nitrogen gases between land and atmosphere are strongly affecting Earth’s atmospheric composition, air quality, global warming, climate change and human health.
Soil denitrification as a key process of terrestrial N cycle is poorly quantified despite a long research history, but progress is expected from focused effort in recent decades to improve techniques for measuring and modelling N2 and N2O fluxes. Yet we still lack a comprehensive, quantitative understanding of denitrification rates in soils due to methodical limitation, its complex controls and the spatio-temporal variability on a field or landscape scale. Due to the lack of suitable data-sets, process-based denitrification models have rarely been validated and results of their application on site and regional scales are highly uncertain.
This session seeks to improve our understanding of a) how intensification of reactive N use, land management and climate change affects the pools and fluxes of nitrogen in terrestrial and aquatic ecosystems, b) how reactive N enrichment of land and water will affect the future carbon sink of natural ecosystems as well as atmospheric exchanges of reactive (NO, N2O, NH3, HONO, NO2 and non-reactive N (N2) gases with implications for global warming, climate change and air quality, and c) how quantification and prediction of soil denitrification can be improved.
We welcome contributions covering a wide range of experimental and modelling studies, which covers microbes-mediated and physico-chemical transformations and transport of nitrogen across the land-water-air continuum in natural ecosystems from local to regional and global scales. We also invite contributions on methodical advances in measuring denitrification in soils addressing N2 and N2O fluxes with a focus on controlling factors; reports on novel methods; process-based modelling of denitrification at various scales; linking denitrification rates to parameters of the denitrifying community.

Phosphorus (P) is an essential element for life on Earth and is tightly cycled within the biosphere. Throughout geological history, P availability has regulated biological productivity with impacts on the global carbon cycle. Today, human activities are significantly changing the natural cycling of P. Phosphate mining has depleted geological P reserves, while increased inputs of P to terrestrial ecosystems have enhanced fluxes of P to lakes and the oceans.

Direct anthropogenic perturbations of the P cycle, coupled with other human-induced stresses, have impacted numerous environments. Forest ecosystems may be losing their ability to recycle P efficiently, due to excessive N input, extensive biomass removal, and climatic stress. Soils, which serve as the biogeochemical fulcrum of the terrestrial P cycle, have been greatly altered by fertilizer use in recent decades. Changes in the P cycle on land impact on the magnitude and timing of P fluxes into aquatic ecosystems, influencing their trophic state. Burial in sediments returns P to the geological sink, eventually forming economically viable P deposits. Throughout the P cycle, redox conditions play a key role in transformations and mobility of P.

This interdisciplinary session invites contributions to the study of P from across the geosciences, and aims to foster links between researchers working on different aspects of the P cycle. We target a balanced session giving equal weight across the continuum of environments in the P cycle, from forests, soils and groundwater, through lakes, rivers and estuaries, to oceans, marine sediments and geological P deposits. We welcome studies of both past and present P cycling, with a focus on novel techniques and approaches.

The Amazon forest is the world’s largest intact forest landscape. Due to its large biodiversity, carbon storage capacity, and role in the hydrological cycle, it is an extraordinary interdisciplinary natural laboratory of global significance. In the Amazon rainforest biome, it is possible to study atmospheric composition and processes, biogeochemical cycling and energy fluxes at the geo-, bio-, atmosphere interface under near-pristine conditions and under anthropogenic disturbance of varying. Understanding its current functioning at process up to biome level in its pristine and degraded state is elemental for predicting its response upon changing climate and land use, and the impact this will have on local up to global scale.
This session aims at bringing together scientists who investigate the functioning of the Amazon and comparable forest landscapes across spatial and temporal scales by means of remote and in-situ observational, experimental, modelling, and theoretical studies. Particularly welcome are also presentations of novel, interdisciplinary approaches and techniques that bear the potential of paving the way for a paradigm shift.

The Paris Agreement on Climate sets the international objective to keep climate warming well below two degrees. This extraordinary challenge requires a dramatic improvement of current scientific capabilities to estimate the budgets and their trends of greenhouse gases (GHG) at regional scale, and how they link up to the global growth rates of the major GHGs (N2O, CH4 and CO2). This session aims to bring together studies to help understand and quantify regional budgets, trends and variability, and drivers of major GHG (N2O, CH4 and CO2) through the analyses of emissions inventories, field and remotely-sensed observations, terrestrial and ocean biogeochemical modeling, and atmospheric inverse modeling. We encourage contributions from the REgional Carbon Cycle Assessment and Processes (RECCAP2), a new global assessment of the Global Carbon Project, as well as studies combining different datasets and approaches at multi-scales from regional to global.

The Arctic is warming more than twice as fast as the global average, making climate change’s polar effects more intense than anywhere else in the world. The Arctic accounts for half of the organic carbon stored in soils. There is high confidence that the thaw of terrestrial permafrost will lead to carbon release, but only low confidence regarding timing, magnitude and relative role of different GHG’s according to the sixth assessment report of IPCC (2021).

Therefore, in this session we aim to bring together biogeochemical science in high latitude regions. From small scale processes such as those measured by flux chambers, to site-scale eddy covariance fluxes, to regional scale atmospheric carbon cycle measurements, all the way to pan Arctic monitoring by satellites. We are interested in both measurements of high latitude carbon and nutrient cycles as well as environmental changes.
In this session we encourage abstracts with new findings on high latitude biogeochemical research such as CO2, CH4 or N2O fluxes, but also groundwater nutrient flow or atmospheric concentrations and their sources. We also encourage submissions on environmental change topics such as Arctic greening, wetlands extent change, and permafrost degradation, and ways to map these changes based on remote sensing.

Finally, large-scale high latitude projects such as: AMPAC a transatlantic initiative by NASA and ESA, which brings together a wide range of high latitude CH4 focused activities from Europe as well as North America. But also projects such as ABoVE, Permafrost Pathways, Q-Arctic,. Are welcome.

The use of geological evidence may help the judicial system to solve cases of homicides, corpse concealments, hit-and-run accidents, kidnappings, sexual assaults, geohazard problematics, environmental damages, animal maltreatment, wildlife crimes, gemstone and fossil frauds. Forensic geologists may be supported by a team of experts during the scientific investigation.
Earth and Natural Sciences may be simultaneously involved in a holistic approach for analyzing inorganic, anthropogenic, and organic materials found on the outdoor crime scenes. These sciences may also be devoted to environmental issues due to the human-environmental interactions responsible for crucial human-driven changes in the Anthropocene and hazards in which biodiversity, climate, and public health and safety are at stake.
Different analytical methods aim to obtain information on the compatibility degree among unknown and known samples and the possible provenance.
Based on the above, different experts may collaborate with geologists and investigate geological evidence and environmental issues, together in research teams. Geologists approaching forensic geology need to master sedimentology, micropaleontology, physical geology, petrography, gemology, geochemistry, hydrogeology, soil sciences, geomorphology, stratigraphy, regional geology, remote sensing, and applied geology and geophysics. Botanists address their investigation in forensic botany by studying plant ecology, vegetal anatomy, systematics, palynology, algology, and plant DNA in soil/sediment. On the other hand, entomologists approach forensic entomology by studying chemistry, biology, human/animal health, molecular science, and animal DNA in soil/sediment.
We encourage submission of studies presenting new insights derived from different inter-disciplinary- and transdisciplinary perspectives, including earth, natural, and environmental sciences (geology, geophysics, geochemistry, ecology, geological medicine, botany, entomology, ecology, and climatology applied to the Anthropocene Epoch), legal medicine, geological medicine. Particular attention will be given to the following topics: comparative analyses; reconstruction of walking in crime scenes; search for clandestine graves; geographical profiling; gemstone frauds; pollutants in groundwaters and soil matrices and environmental forensics; ecological and human health risks.

This session is open to all contributions in biogeochemistry and ecology where stable isotope techniques are used as analytical tools, with foci both on stable isotopes of light elements (C, H, O, N, S, …) and new systems (clumped and metal isotopes). We welcome studies from both terrestrial and aquatic (including marine) environments as well as methodological, experimental and theoretical studies that introduce new approaches or techniques (including natural abundance work, labelling studies, multi-isotope approaches).

As part of this session we invite contributions from the field and laboratory experiments and the very latest instrument developments as well as theoretical and modeling activities that advance our understanding of biogeochemical and atmospheric processes using stable isotopes of light elements (C, H, O, N) as well as other novel tracers (such as carbonyl sulfide (COS)), for example:

- Stable isotopes in carbon dioxide (CO2), water (H2O), methane (CH4), carbonyl sulfide (COS), and nitrous oxide (N2O)

- Novel tracers and biological analogues, such as carbonyl sulfide (COS)

- Polyisotopocules ("clumped isotopes")

- Intramolecular stable isotope distributions ("isotopomer abundances")

- Analytical, method and modeling developments

- Flux measurements

- Quantification of isotope effects

- Non-mass-dependent isotopic fractionation and related isotope anomalies

This session aims to bring together scientists from different fields applying single and dual oxygen and hydrogen isotope approaches on environmental-derived compounds for the reconstruction of climatic and biological processes that go beyond standard isotope analyses of water. We invite researchers working on different compounds (e.g. lipids, (hemi-) cellulose, non-structural carbohydrates) from aquatic (e.g., fish, microbes and seaweed) and terrestrial (e.g., grasses, mosses and trees) origins across all spatiotemporal scales and archives (e.g. herbarium, peat, sediments, loess and tree rings). We also encourage people working with all techniques (IRMS-, NMR- or spectroscopy-based) to present advances in methods, as well as researchers focusing on improving oxygen and hydrogen isotope-based models to discuss their approaches. In summary, the session will offer an overview on oxygen and hydrogen applications across different ecosystems in order to facilitate the interpretation of compound-specific isotope patterns.

Natural organic matter (NOM) is ubiquitous and astonishingly complex, and this complexity may be pivotal in sustaining various ecosystem services such as nutrient cycling and carbon storage. For example, microbial uptake, respiration and release of organic matter ultimately control a carbon reservoir larger than all living biomass on earth combined. Organic molecules such as DNA and biomarkers have received increasing attention as tools to reconstruct long-term changes in biodiversity, microbial element cycling, organic matter composition, and environmental constraints.
Our session will thus focus on the following topics:
• NOM biogeochemistry
Modern geochemical tools such as nuclear magnetic resonance spectroscopy, ultrahigh resolution mass spectrometry or liquid chromatography coupled to tandem mass spectrometry show great prospects for revealing the multifaceted nature of NOM, i.e., attributing its variety of functions to the extremely diverse molecular composition of NOM. Key questions include: How can we disentangle the properties, functions, and responses of NOM in terrestrial and marine ecosystems, and which new techniques and experimental setups can help us to achieve this?
• Microbe-DOM interactions
Understanding the main mechanisms regulating the biological availability of DOM is one of the most challenging, but pressing issues in environmental science. In biogeochemical modelling studies, DOM is still over-simplistically parameterized, and linking DOM composition to more easily measured proxies from optical measurements (CDOM/FDOM) remains challenging. Contributions include experimental studies and field observations along environmental gradients, data science approaches focusing on algorithm development, studies linking microbial and biogeochemical data, as well as biogeochemical modelling approaches.
• Biomarkers and environmental DNA
Recent developments in the analysis of biomarkers (lipids, photo-pigments, sterols, etc.) and DNA extracted from environmental samples enable unique insights into the history of terrestrial, freshwater, and marine ecosystems. Molecular techniques offer a differentiated view on the climate-environment-human nexus through investigation of leads/lags in specific proxies resolving cultivated plants, domestic animals, industrial activity, and climate. This section targets advances and challenges when using biomolecules for paleo-environmental reconstructions and covers novel analytical approaches and data analysis.

Carbonate minerals are ubiquitous throughout all geological environments in the Earth`s crust, forming via biogenic, marine, diagenetic, hydrothermal, magmatic, and metamorphic processes. Therefore, refining our understanding of carbonate formation can contribute towards addressing important geological and societal problems, such as the Earth`s past and present carbon cycle or the exploration of critical raw materials. The study of carbonate minerals is one that crosses multiple sectors and disciplines, with several novel applications emerging in recent years. Similarly, recent analytical developments allow for the application of geochronological, trace element and isotope geochemical techniques across a wide range of scales and sample materials. To keep track of these emerging techniques, this session aims to bring together an interdisciplinary community working both on method development and on the application of techniques investigating carbonate minerals. We invite geoscientists from all fields (e.g., paleoceanology, economic geology, igneous petrology, carbon storage) to contribute to this session by presenting their research in carbonate geochronology (e.g., U-Pb dating), carbonate trace element geochemistry (e.g., rare earth elements), and carbonate isotope geochemistry (e.g., strontium, clumped isotopes).

Finding the best method both to monitor environmental processes occurring at the earth surface and to explore data related to them is a challenge for many scientists. The spatial and temporal extension of a process and the observation scale chosen can strongly conditionate the fully understanding of the phenomenon itself. Further, the structural peculiarities of the geochemical data, describing the composition of the matrices used to monitor the environment, are often capable to hidden meaningful relationships among elements in favor of spurious correlations dependent on the so-called closure effect affecting them.
The intrinsic aim of this session is to propose a comparison of methods, including both innovative monitoring and data elaboration techniques, with the purpose of providing a real time review of the pros and the counter associated to the different approaches reported. All the scientists using geochemical data to evaluate the impact of human activities on the environment and aiming at finding the “best solution” for the spatial and temporal discrimination of contamination are invited to contribute to this session.
Studies on single matrices are welcome although research based on the outcomes of integrated plans based on several matrices, including biological ones, would be of greater interest. Similarly, contributions focusing on data elaboration techniques using multivariate analysis and machine learning are encouraged especially if they consider the compositional nature of geochemical data.

The MacGyver session focuses on novel sensors made, or data sources unlocked, by scientists. All geoscientists are invited to present:
- new sensor systems, using technologies in novel or unintended ways,
- new data storage or transmission solutions sending data from the field with LoRa, WIFI, GSM, or any other nifty approach,
- started initiatives (e.g., Open-Sensing.org) that facilitate the creation and sharing of novel sensors, data acquisition and transmission systems.

Connected a sensor to an Arduino or Raspberri Pi? Used the new Lidar in the new iPhone to measure something relevant for hydrology? 3D printed an automated water quality sampler? Or build a Cloud Storage system from Open Source Components? Show it!

New methods in hydrology, plant physiology, seismology, remote sensing, ecology, etc. are all welcome. Bring prototypes and demonstrations to make this the most exciting Poster Only (!) session of the General Assembly.

The MacGyver session this year teams up with the Frontiers in river flow monitoring session. The 'author in attendance' blocks are in the early morning and late afternoon. In between those two block we organize a field session with hands-on on different state of the art hydrometry techniques. Bring your own measurement system and show case it, or join us to see others demonstrate their devices! Details on this field trip:

Monday, 24th of April, 10:30 to 16:00 hrs
Departure by bus at 10:30 hrs from AVC Center
Platz der Vereinten Nationen close to underground station Kaisermühlen VIC
Lunch and beverages will be provided

If you are interested please send us an email: pena@photrack.ch

This session is co-sponsered by MOXXI, the working group on novel observational methods of the IAHS.

The Quaternary Period (last 2.6 million years) is characterized by frequent and abrupt climate swings that were accompanied by rapid environmental change. Studying these changes requires accurate and precise dating methods that can be effectively applied to environmental archives. A range of different methods or a combination of various dating techniques can be used, depending on the archive, time range, and research question.
Radiocarbon (14C) in particular is a key environmental tracer that can be widely applied in geochronology, environmental, and climate sciences. It is an invaluable tool to understand the global carbon cycle, as it can be used to trace the transfer of carbon between the atmosphere and other reservoirs, e.g., soils, oceans, and the geosphere, and to understand the impact of anthropogenic perturbations on these reservoirs.

With this session, we aim at bringing together an interdisciplinary group of researchers focused on dating and understanding climate archives of the Quaternary Period. Our session will focus on the application of geochronometers on one hand, as well as on the use of radiocarbon from natural reservoirs and archives that improve our understanding of the carbon cycle. In particular, we look forward to discussing (1) experimental and analytical advances (e.g. in sample preparation and measurement techniques); (2) methods that reduce, quantify and express dating uncertainties in any dating method, including high-resolution radiocarbon approaches; (3) new insights into the global carbon cycle, e.g., storage times in soils, sediment dispersal, ocean circulation, or carbon transfer between reservoirs; (4) general geochronological applications such as long-term landscape evolution, rates of geomorphological processes, and chronologies for records of climate change.

Agrogeophysics harnesses geophysical methods such as ground-penetrating radar, electrical imaging, seismic,... from hand-held over drone to satellite-borne, to characterize patterns or processes in the soil-plant continuum of interest for agronomic management. These methods help develop sustainable agricultural practices by providing minimally-invasive, spatially consistent, multi-scale, and temporally-resolved information of processes in agro- ecosystems that is inaccessible by traditional monitoring techniques. The aim of this session is to feature applications of geophysical methods in agricultural research and/or show methodologies to overcome their inherent limitations and challenges. We welcome contributions monitoring soil or plant properties and states revealing information relevant for agricultural management; studies developing and using proximal or remote sensing techniques for mapping or monitoring soil-water-plant interactions; work focused on bridging the scale gap between these multiple techniques; or work investigating pedophysical relationships to better understand laboratory-scale links between sensed properties and soil properties and states of interest. Submissions profiting on data fusion, utilizing innovative modeling tools for interpretation, and demonstrating novel acquisition or processing techniques are encouraged.

Plant traits extend the range of earth observations to the level of individual organisms, providing a link to ecosystem function and modelling in the context of rapid global changes. However, overcoming the differences in temporal and spatial scales between plant trait data and biogeochemical cycles remains challenging.

This session will address the role of plant traits, biodiversity, acclimation, and adaptation in the biogeochemical cycles of water, carbon, nitrogen, and phosphorus. We welcome conceptual, observational, experimental and modelling approaches and studies from the local to the global scale, including in-situ or remote sensing observations.

Carbon allocation is a key process in ecosystems: it is coupled with plant growth, fuels metabolism and plays a crucial role for carbon sequestration in standing biomass and soil organic matter. While the importance of carbon allocation for plant and ecosystem functioning and the carbon balance is widely recognized, we still lack a comprehensive understanding of the underlying mechanisms, responses to global changes and wider biogeochemical implications. Open questions include: 1) what drives carbon allocation in plants and ecosystems?; 2) what is the fate of newly assimilated carbon?; 3) what determines the allocation of nonstructural carbon to growth, metabolism and storage?, 4) how does carbon allocation affect nutrient and water relations in plants and ecosystems?; and 5) how do allocation patterns change under changing environmental conditions and what are the consequences for biogeochemical cycles? This session invites contributions from observational, experimental and modelling studies.

The health and productivity of crops, forests and natural plant communities are constrained by the increasing occurrence of climate extremes such as droughts, heat waves and frost events. Such climate extremes can trigger or amplify disturbances including insect outbreaks, wildfires and dieback-mortality episodes altering the structure, composition, and functioning of crops, forests and vegetation worldwide.
The mechanisms of plant dieback, often related to hydraulic failure and carbon starvation, have not been fully unravelled and linked to specific functional traits, leading to a need for multi-proxy approaches.
Understanding the plasticity of plant traits and mechanisms for acclimation is a key requisite for:
i) forecasting plant population dynamics and climate change-driven changes in community composition in natural plant ecosystems, and
ii) managing cultivation factors in crop systems (also in controlled environment agriculture – CEA - and in Bioregenerative Life Support Systems in extreme environments as Space) for resource use optimization to achieve sustainability goals, particularly under unfavorable climate conditions.
This session provides a forum on the role of functional traits (e.g., plant size, specific leaf area, leaf anatomy, leaf life span, leaf nitrogen content, seed mass, plant/root architecture, phenology, quantitative wood anatomy, wood density, hydraulic traits, etc.) as indicators and proxies of plant status and post-disturbance resilience.
We encourage contributions to the session that: (i) provide quantitative knowledge regarding the intra- and inter-specific diversity in functional traits for predicting plant vulnerability to environmental stressors; (ii) assess the potential of traits to acclimate under changing environmental conditions; (iii) show the ability of traits to serve as indicators of plant performance, survival and resilience; (iv) detect possible trade-offs among traits (e.g., coordination between hydraulic and photosynthetic processes) related to resource acquisition and allocation.
A multidisciplinary effort is needed to unravel plant acclimation and adaptation strategies and upscale gained information to evaluate implications for productivity of croplands, forests and natural terrestrial ecosystems as well as in CEA. Such information will be useful as input for dynamic global vegetation and crop models supporting international policy for sustainability.

The majority of world forest ecosystems are subject to a number of natural disturbances (e.g. wildfires, pests, diseases, adverse weather events). These can severely affect their health and vitality by causing tree mortality or by reducing their ability to provide the full range of goods and services. Understanding and quantifying forest vulnerability to such disturbances and the underlying driving mechanisms is crucial to assess climate impacts and develop effective adaptation strategies.
This session will cover aspects ranging from observed and projected climate change to consequences for forest ecosystems and forest assessment, spanning a range of scales and conditions. In particular, we welcome submissions on the following subjects:

• Forest mortality and die-back phenomena under global warming.
• Evaluation of the effects of natural and anthropogenic disturbances on forest health and growth.
• Vulnerability of old-growth forests and mountainous forest ecosystems to climate change.
• Multidisciplinary approaches towards monitoring and modelling tree vulnerability at the local, regional and global scale.
• Estimation of resistance, resilience and recovery of forests in drought-prone areas.
• Interdisciplinary forestry research covering not only ecological but also economic and social aspects.
• Effects of forest adaptive management on forest health and vulnerability.
• Methods and tools for decision support and adaptation support in the forestry sector.
• Modelling growth at different scales: wood, tree, forest.

Forest ecosystems play a crucial role in the global carbon budget, with mature forests being the most important land carbon sink. . However, the capacity of terrestrial ecosystems to continue sequestering carbon under climate change remains unclear. In order to accurately predict their resilience to future warming, increasing CO2 concentrations, and subsequent feedback to the climate system, there is a need for improved understanding of forest responses at all scales, from physiology to the ecosystem level responses. We aim to gather new knowledge/data sets from global change experiments, remote sensing and modelling studies from forests across the world, including recent field warming and elevated CO2 experiments. We welcome work on organ- to ecosystem-level responses to warming and CO2 as well as work that helps to elucidate how such processes could be represented within vegetation modelling frameworks. With this session, we aim to broaden the mechanistic understanding of forest ecosystems and what their response to the imminent increases in atmospheric CO2 and temperature will mean for their capacity to sequester carbon.

Although climate change is a natural process, it is significantly stimulated by anthropogenic activities. The acceleration of climate change is directly connected with ecological stability, soil degradation, and hydrological extremes, which are considered as the main consequences of climate change. As climate change intensifies, extreme and unexpected weather events are becoming more frequent.
The aim of this session is to highlight a broad range of research methods and results related to climate change. This interdisciplinary session should reflect, discuss, and share scientific knowledge on a local and regional scale with the aim to increase innovative knowledge on climate change and its impacts, ecosystem response and new techniques to prevent and reduce the negative consequences.

This session awaits a variety of studies related to:
- climate change impacts (biodiversity loss, rising temperatures, hydrological change and extremes, soil degradation, ecosystem response to climate change);
- drought, precipitation deficiency or extreme precipitation with solutions aimed at reducing the negative impacts of droughts;
- ecological stability and climate change - how climate change affects ecological stability (reducing the degree of ecological stability, deforestation, human interactions with the environment) and evaluation of restoration success;
- construction of green buildings to support and increase the stability of the landscape;
- techniques and methods to prevent and reduce the negative impacts of climate change (such as soil degradation, carbon sequestration, changes in natural, agricultural, and forest ecosystems, reduction of overall ecological stability and character of the landscape);
- in addition, attention will be given to the sustainability of management practices, the importance of appropriate land use management as the main tool for preventing the degradation processes, the distribution and vitality of ecosystems, and improving the condition of forest ecosystems in order to increase the overall character of the landscape.

Natural disturbances are a primary driver of forest dynamics, thus shaping their composition and structure, and determining succession trajectories. Humans have always interacted with natural disturbances, and are in turn affected by the hazards posed by these events.
With the multitude of functions and services simultaneously and increasingly required from forest ecosystems, it is crucial to improve our understanding of the impact of natural disturbances on forests, also in light of the potential alterations introduced by different global change drivers, mostly due to anthropogenic activities.
Further attention is required to the many ways in which multiple disturbances (of biotic, abiotic and anthropogenic origin) interact with each other, thereby modifying the likelihood of occurrence and the effects of one another.
Despite an increasing awareness of the fundamental ecological role of natural disturbances, forest management still requires solid scientific input on how to increase the resistance and resilience of forests, and manage naturally disturbed landscapes to promote forest regeneration.
This complex situation calls for multi-scale, multi temporal, and multidisciplinary studies, taking advantage of field (in-situ) and remote sensing approaches, in order to capture the large heterogeneity and variability of the patterns and processes involved.
In the framework of the UN Decade on Ecosystem Restoration, preventing, halting and reversing forest ecosystems degradation due to lack of disturbances or altered disturbance regimes should become a focus of sustainable forest management.
In this session, we invite contributions from all fields in order to promote knowledge on disturbance ecology and management, aiming at developing methodologies and strategies to mitigate the impact of global change and its consequences on natural disturbances affecting forest ecosystems worldwide.

Climate change is happening faster at high latitudes than anywhere else on the Globe. Cryosphere biomes and high latitude ecosystems are vulnerable to a warmer climate, significantly changing their functioning with important feedbacks to global element cycling and climate.
Given the strong urgency of tackling the climate challenge and the particularly important role of high latitude ecosystems, this session is dedicated to integrating our understanding of global change effects in high latitude ecosystems based on experimental, observational and modelling approaches. We encourage presentations focusing on the impact of disappearing permafrost soil, acceleration of ‘Arctic greening’ and glacier retreat, short- and long-term effects of warming, elevated atmospheric CO2 levels, changes in precipitation, nutrient input, and combinations of multiple global change drivers. Meta-analyses and integrated studies combining observational, experimental and/or modelling approaches are also welcomed.

A fundamental understanding of biosphere-atmosphere interactions is an invaluable asset for accurately representing the terrestrial carbon, water, and energy cycles. Multiple processes determine how the exchange of mass, energy, and momentum scale from leaf to plant, to ecosystem, and eventually to the entire globe. Challenges remain in robustly formulating the mechanistic underpinnings of these biogeochemical processes across all these scales and improving process-based modelling efforts without falling into a complexity trap. At the same time, we are facing increasing availability of data at multiple scales, ranging from leaf-level measurements (e.g., gas exchange), tree-level measurements (e.g., sap flow and tree growth, dendroecology), ecosystem-level measurements (eddy covariance towers, UAVs, aircrafts) to synoptic Earth observations from space. These are opening to utilize machine learning algorithms and data-driven modelling as an alternative to process-based approaches. Though sometimes very successful in fitting observations, they are often plagued by lack of interpretability and physical consistency. However, recent developments like interpretable machine learning, physics-aware regression or causal inference models are attempts to mitigate these issues.
This session invites studies that improve our overall understanding of biosphere-atmosphere interactions by combining observations at different temporal and spatial scales as well as their seamless integration into modelling strategies. In addition to empirical multi-scale observations of carbon, energy and water fluxes, we invite research that explores data-driven diagnostics and constraints for model evaluation (e.g., Emergent Constraints), data-driven parameterizations in mechanistic models (e.g., Earth system models) and other developments of machine-learning / hybrid modelling strategies (e.g., fusion of data-driven approaches and mechanistic models, interpretable machine learning, causal inference) for an integrated understanding of carbon, energy and water fluxes across scales.

A wide range of processes influence the response of the vegetation, soils, and terrestrial carbon fluxes to changes in land and atmospheric moisture availability. Such responses also occur over a wide range of time scales, ranging from extreme events like floods, droughts or heatwaves, to long-term shifts in background climate. In addition, the vegetation and soils regulate land-atmosphere moisture and energy fluxes, which in turn feed back to the broader climate system.

Advances in remote sensing, experimental studies, and the growing number of in situ measurements and ecosystem trait databases can now be combined with machine learning, statistical approaches and/or mechanistic models, to understand how plants, soils, and ecosystems respond to climate variability. Combining these data in innovative ways will help to evaluate and improve models of plant-stress and carbon exchange, and in-turn climate projections.

Contributions might include, for example, regional to global evaluations of the vegetation and ecosystem response to various environmental stressors (e.g. soil moisture, temperature, etc.) and climatic variability, using in-situ and/or satellite observations to evaluate or improve the representation of water-carbon interactions and biological processes in models, new representations of plant and ecosystem response to land and atmospheric moisture stress (e.g. through plant hydraulics, optimality approaches, etc.), and improvements in our understanding of how soils and plant-stress regulate surface fluxes and boundary layer processes.

Solicited authors:
Charlotte Grossiord, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
René Orth, Max Planck Institute for Biogeochemistry, Jena, Germany

Human activities are altering a range of environmental conditions, including atmospheric CO2 concentration, climate, and nutrient inputs. However, understanding and predicting their combined impacts on ecosystem structure and functioning and biogeochemical cycles is challenging. Divergent future projections of terrestrial ecosystem models reveal uncertainties about fundamental processes and missing observational constraints. Models are routinely tested and calibrated against data from ecosystem flux measurements, remote sensing, atmospheric inversions and ecosystem inventories. However, it remains challenging to use available observations to constrain process representations and parameterizations in models simulating the response of ecophysiological, biogeochemical, and hydrological processes to environmental changes.

This session focuses on the influence of CO2, temperature, water stress, and nutrients on ecosystem functioning and structure. A focus is set on learning from experiments and novel uses of continuous ecosystem monitoring and Earth observation data for informing theory and ecosystem models. Contributions may cover a range of scales and scopes, including plant ecophysiology, soil organic matter dynamics, soil microbial activity, nutrient cycling, plant-soil interactions, or ecosystem dynamics.

The need to predict ecosystem responses to anthropogenic change, including but not limited to changes in climate and increased atmospheric CO2 concentrations, is more pressing than ever. Global change is inherently multi-factorial and as the terrestrial biosphere moves into states without a present climate analogue, mechanistic understanding of ecosystem processes and their linkages with vegetation diversity and ecosystem function is vital to enable predictive capacity in our forecast tools. For example, climate change can also force surface moisture and temperature across thresholds, beyond which dryland mechanisms of ecosystem functioning, currently prevalent in dry biomes, will emerge in historically more humid biomes.
This session aims to bring together scientists interested in advancing our fundamental understanding of vegetation and whole-ecosystem processes. This year we have a special focus on dryland mechanisms (Grünzweig et al. 2022). We are interested in contributions focused on advancing process- and hypothesis-driven understanding of plant ecophysiology, biodiversity and ecosystem function. We welcome studies on a range of scales from greenhouse and mesocosm experiments to large field manipulative experiments, remote sensing studies and process-based modelling. We encourage contributions of novel ideas and hypotheses in particular those from early stage researchers and hope the session can create an environment where such ideas can be discussed freely.

Grünzweig et al. 2022. Dryland mechanisms could widely control ecosystem functioning in a drier and warmer world. Nature Ecol. Evol. 6, 1064–1076. doi 10.1038/s41559-022-01779-y

Land use and land cover change (LULCC), including land management, has the capacity to alter the climate by disrupting land-atmosphere fluxes of carbon, water and energy. Thus, there is a particular interest in understanding the role of LULCC as it relates to climate mitigation (e.g., CO2 removal from the atmosphere) and adaptation (e.g., shifts in land use or management) strategies. Recent work has highlighted tradeoffs between the biogeophysical (e.g. changes in surface properties such as albedo, roughness and evapotranspiration) and biogeochemical effects (e.g., carbon and nitrogen emissions) of land management and change on weather and climate. However, characterizing the relationship between these effects with respect to their extents and the effective net outcome remains challenging due to the overall complexity of the Earth system. Recent advances exploiting Earth system modelling and Earth observation tools are opening new possibilities to better describe LULCC and its effects at multiple temporal and spatial scales. An increasing focus on land-based mitigation and adaptation strategies to meet more stringent emissions targets has expanded the range of land management practices considered specifically for their potential to alter biogeophysical and biogeochemical cycles. This session invites studies that improve our understanding of LULCC-related climate and weather perturbations from biogeophysical and biogeochemical standpoints, either separately or focused on the intersection between these two factors. This includes studies focusing on LULCC that can inform land-based climate mitigation and adaptation policies. Observation-based and model-based analyses at local to global scales are welcome, including those that incorporate both modeling and observational approaches.

The terrestrial vegetation carbon balance is controlled not just by photosynthesis, but by respiration, carbon allocation, turnover (comprising litterfall, background mortality and disturbances) and wider vegetation dynamics. Observed, and likely future, changes in vegetation structure and functioning are the result of interactions of these processes with atmospheric carbon dioxide concentration, nutrient availability, climate and human activities. The quantification and assessment of such changes has proven extremely challenging because of a lack of observations at large scales and over the long time periods required to evaluate trends.

This limited observation base gives rise to high uncertainty as to whether the terrestrial vegetation will continue to act as a carbon sink under future environmental changes, or whether increases in autotrophic respiration or carbon turnover might counteract this negative feedback to climate change. For instance, will accelerated background tree mortality or more frequent and more severe disturbance events (e.g. drought, fire, insect outbreaks) turn vegetation into carbon sources? How will shifts in dynamics of plant mortality, establishment and growth influence forest composition?

Uncertainties and/or data gaps in large-scale empirical products of vegetation dynamics, carbon fluxes and stocks may be overcome by extensive collections of field data and new satellite retrievals of forest biomass and other vegetation properties. Such novel datasets may be used to evaluate, develop and parametrize global vegetation models and hence to constrain present and future simulations of vegetation dynamics. Where no observations exist, exploratory modelling can investigate realistic responses and identify necessary measurements. We welcome contributions that make use of observational approaches, vegetation models, or model-data integration techniques to advance understanding of the effects of environmental change on vegetation dynamics, tree mortality and carbon stocks and fluxes at local, regional or global scales and/or at long time scales.

Climate change is affecting the dynamic feedbacks between plant, soil, and microbial communities and thus strongly influences terrestrial biogeochemical cycling. In this session we address the question: What is the impact of changing environmental conditions on the plant-soil system, and what are the resulting effects on soil biogeochemistry? Given the positive and negative feedbacks with the climate system, dynamics of soil organic matter across terrestrial ecosystems are a key focus of this session.
We invite contributions from manipulative field experiments, observations in natural-climate gradients, and modelling studies that explore the climate change impacts on plant-soil interactions, biogeochemical cycling of C, N, P, microbial diversity and decomposition processes, and deep-soil biogeochemistry. Submissions that adopt novel approaches, e.g. molecular, isotopic, or synthesize outputs from large-scale, field experiments focusing on plant-soil-microbe feedbacks to warming, wetting, drying and thawing are very welcome.

Soils sustain complex patterns of life and act as biogeochemical reactors producing and consuming a large amount of gas molecules. They play a fundamental role in the temporal evolution of the atmospheric gases concentration (greenhouse gases, biogenic volatile organic compounds, nitrous acid, isotopic composition…) and they modulate the soil pore gas concentrations affecting many soil functions, such as root and plant growth, microbial activity, and stabilization of soil organic carbon. Gases production, consumption and transport in the different soil types have then some important ecological implications for the earth system.
The factors affecting the soil gas processes range from physical soil structure (porosity, granulometry,…), type and amount of living material (microbiota, root systems), soil chemistry properties (carbon and nitrogen contents, pH,…) and soil meteorological conditions (temperature, water content,…). A large mixing of different scientific backgrounds are therefore required to improve the knowledge about their influence which is made even more difficult due to the very large spatial heterogeneity of these factors and the complexity of their interactions.
This session will be the place to present and exchange about the measurement techniques, data analyses and modelling approaches that can help to figure out the temporal and spatial variability of the production/consumption and transport of gases in soils. In addition to mechanisms related to carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), including the geochemical ones, the abstracts about volatile carbon compounds produced by plant and microbial or Helium and Radon geogenic emissions production are welcome
A special attention will be given to the researches including special water situations as edaphic drought or waterlogged soils

Tropical peatlands store around 105 Gt carbon (C ), although their total extent remains uncertain due to inadequate data. In a natural condition, tropical peatlands are long-term C stores and support livelihoods, but anthropogenic disturbances (logging, drainage, degradation, agricultural conversion, fire, resource exploration) are increasing in extent. These transformations result in high C loss, reduced C storage, increased greenhouse gas (GHG) emissions, loss of hydrological integrity, peat subsidence, increased risk of fire. For agricultural peatlands, changes in nutrient storage and cycling necessitate fertilizer use, with enhanced emissions of N2O. Under a warming climate, these impacts are likely to intensify and reduce the benefits to rural communities. This session welcomes contributions on all aspects of tropical peatland science, including peatland mapping and monitoring; the impact of climate on past, present and future tropical peatland formation, accumulation and C dynamics; GHG and nutrient flux dynamics; management strategies for GHG emissions mitigation and the maintenance or restoration of C sequestration and storage; and valuing ancestral knowledge of peatlands. Field based, experimental and modelling studies of intact and modified systems from all tropical regions are welcomed.

Peatlands are threatened by a number of anthropogenic activities such as drainage, peat cutting, eutrophication and climate change. Peatland restoration for conservation purposes can solve many problems related to drained peatlands and has been implemented for decades now. However, innovative management measures that sustain economically viable biomass production while reducing negative environmental impacts including greenhouse gas (GHG) emissions, fire risk and supporting ecosystem services of organic soils are only currently studied. Those management measures include, but are not limited to, productive use of wet peatlands (paludiculture), improved water management in conventional agriculture and innovative approaches in conservation-focused rewetting projects. Besides work on global change effects on unmanaged peatlands, we invite studies addressing all types of peatland management, i.e. agriculture, forestry and “classical” restoration, their integration into GHG inventories and their impacts on ecosystem services and biodiversity regionally and nationally as well as their integration into GHG inventories. Work on all spatial scales from laboratory to national level addressing biogeochemical and biological aspects and experimental and modelling studies are welcome. Furthermore, we invite contributions addressing policy coherence and identifying policy instruments for initiating and implementing new management practices on organic soils.

Managed agricultural ecosystems (grassland and cropland) and forests are an important source and/or sink for the greenhouse gases (GHG) CO2, CH4, and N2O as well as for reactive trace gases. Representative measurements and modelling under typical conditions as well as for potential mitigation options are necessary as a basis for recommendations to policy makers, farmers, and foresters.
Due to the simultaneous influence of various environmental drivers and management activities (e.g. fertilizer application, harvest, grazing) the flux patterns are often complex and difficult to attribute to individual drivers. Moreover, management related mitigation options may often result in trade-offs between different GHG or between emission of GHG and reactive gases like NH3, NOx, or VOCs. To investigate these interactions, the session addresses experimentalists and modelers working on carbon and nitrogen cycling processes and related fluxes on plot, field, landscape, and regional scale. It is open to a wide range of studies including the development and application of new devices, methods, and model approaches as well as field observations and process studies. Particularly welcome are studies on multiple gases and on the full carbon, nitrogen or GHG budgets. We also encourage contributions about the applicability and overall potential of mitigation options.

Soil systems harbor a high spatial complexity and soil architecture with diverse functions that shape biogeochemical matter cycles. In this session, we host novel studies that illuminate functional soil architectures and the spatial heterogeneity in soils from biological, physical, and chemical perspectives related to organic matter dynamics and other biogeochemical processes.

The advent of sophisticated instrumental techniques and advanced modeling tools has enabled studying soil structure, properties, and emerging functions. Spatially-explicit approaches extend our comprehension of heterogeneously distributed microbial habitats and processes, interactions of organic matter with mineral phases, and element storage. Aggregate structures and the void network of soil systems provides a dynamic scaffolding, which can protect soil components and influence local water retention and elemental distribution. Pedogenetic soil processes drive the differentiation at pedon scale and can result from a combination of small-scale processes determining soil ecosystem fluxes. Across different scale and structures, we look forward to discuss insights from microbial microenvironments via aggregated soil architecture up to the pedon scale.

This session is of interest to soil scientists with complementary biogeochemical and physical backgrounds working at different scales. The session responds to the growing awareness of the importance of spatial heterogeneity and architecture for ecosystem-relevant soil functions, such as the occlusion of organic residues, microbial colonization, provision of water and nutrients, and many more. We aim to present and discuss recent achievements, current obstacles, and future research directions to strengthen our conceptual understanding of the linkage of spatial heterogeneity and soil architecture with soil functions and organic matter dynamics across scales.

Soil organic matter (SOM) is well known to exert a great influence on physical, chemical, and biological soil properties, thus playing a very important role in agronomic production and environmental quality. Globally SOM represents the largest terrestrial organic C stock, which can have significant impacts on atmospheric CO2 concentrations and thus on climate. The changes in soil organic C content are the result of the balance of inputs and losses, which strongly depends on the processes of organic C stabilization and protection from decomposition in the soil. This session will provide a forum for discussion of recent studies on the transformation, stabilization and sequestration mechanisms of organic C in soils, covering any physical, chemical, and biological aspects related to the selective preservation and formation of recalcitrant organic compounds, occlusion by macro and microaggregation, and chemical interaction with soil mineral particles and metal ions.

Viticulture is one of the most important agricultural sectors of Europe with an average annual production of 168 million hectoliters (54% of global consumption). The concept of “Terroir” links the quality and typicity of wine to the territory and, in particular, to specific environmental characteristics that affect the plant response (e.g. climate, geology, pedology).
The environmental factors that drive the expression of terroir vary in space and time, as well as soil and crop management.
Understanding the spatial variability of some environmental factors (e.g. soil) is very important to manage and preserve terroirs and face the current and future issues of climate change. In this sense, it is important to stress that in the last decade, the study of terroir has moved from a largely descriptive analysis of geographical variability in land characteristics to a finer elucidation of the relationships between the plant and the environment, which are influenced b