Fire is an essential feature of terrestrial 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. 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, and/or remote sensing. We encourage all abstracts that advance our understanding on interactions between fire and (1) weather, climate, as well as atmospheric chemistry and circulation, (2) biogeochemical, energy, and water cycles, (3) vegetation composition and structure, (4) pyrogenic carbon, including effects on soil functioning and soil organic matter dynamics, (5) cryosphere (e.g. permafrost, sea ice), and (6) humans (e.g., impact of fire on air and water quality, freshwater resources, human health, land use and land cover change, fire management). We also welcome contributions focusing on fire characterization, including (7) fire behavior and emissions (e.g. fire duration, emission factors, emission height, smoke transport), (8) spatial and temporal changes of fire regimes in the past, present, and future, (9) fire products and models, and their validation, error/bias assessment and correction, and (10) analytical tools designed to enhance situational awareness among fire practitioners and early warning systems.

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. 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 N in terrestrial and aquatic ecosystems, and 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 (NH3, N2O, NOx, HONO) and non-reactive N (N2) gases with implications for global warming, climate change and air quality. We welcome contributions covering a wide range of experimental and modelling studies, which cover microbe-mediated and physico-chemical transformations and transport of nitrogen across the land-water-air continuum in natural and managed ecosystems from local to regional and global scales. Furthermore, the session will explore interactions of N with other element cycles (e.g. those of phosphorus and carbon) and highlight the impacts for soil health, biodiversity and water and air quality. Latest developments in methodological and observational approaches for unravelling the complexities of N transformations and transport are of particular interest.

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 rain forest 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 for a part of the year, and under anthropogenic disturbance of varying intensity the rest of the year. 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, 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.

Redox sensitive elements (RSE) are generally found in higher concentrations (compared to their detrital levels) within the sediments deposited in oxygen depleted environments. Although modern ocean waters are well oxygenated, with oxygen deprived settings occurring in isolated basins and high-productivity zones, oxygen-depleted environments were dominating through early Earth’s history. The degree of RSE enrichments in ancient sediments reflects the sedimentary environment that was oxygen-poor. However, we are still lacking tools for more precise description of ancient environments implying need for more extensive interdisciplinary research on mechanism of RSE accumulation in anoxic sediments. In order to understand fully RSE behaviour in anoxic settings one needs to have comprehensive understanding of the overall “chemistry behind”, not only in anoxic environments. This session presents new contributions on RSE present-day investigation in the environment using different techniques (mass spectrometry, isotopic analysis, elemental speciation, solid phase characterization, radiochemical methods) in settings (lakes, rivers, ocean) characterized with different oxygen concentration and oxygen penetration depth in water column and/or sediment, respectively. We encourage contributions using interdisciplinary and multi-analytical approaches targeting description of the RSE sedimentary phases, RSE speciation in aqueous phase, RSE cycling at the oxia/anoxia boundary, i.e., in general research leading towards better understanding of the (bio)geochemistry of RSE.

Mercury (Hg) is a toxic global pollutant of great environmental concern. Anthropogenic activities have altered the global Hg cycle to a great extent and many ecosystems are threatened by exposure to elevated levels of Hg and its different species. For instance, neurotoxic and bioaccumulating methyl-Hg is formed under the influence of anaerobic microorganisms in a variety of natural systems but the controls on this key process are still far from being understood. Further active Hg research areas include exchange processes at the atmosphere-soil-plant interface and their importance for understanding atmospheric Hg deposition, the behavior and long-term fate of Hg at contaminated sites, as well as global cycling models assessing the evolution of historic Hg fluxes from different natural and anthropogenic sources. Recently, a number of novel research tools based on microbiological, spectroscopic, isotopic, and modelling techniques have been developed to improve our understanding of Hg cycling in the environment. This session presents new contributions on present-day Hg cycling in the environment using field-based, experimental, and/or modelling approaches on local to global scales, as well as contributions focusing on long- and short-term reconstruction of Hg as a pollutant over time using natural archives such as ice-cores, tree-rings, lake sediments and peat bogs. We particularly welcome research addressing the effects of global change on Hg cycling as well as the implementation of the Minamata convention on mercury levels in the environment and new approaches to assess its effectiveness.

The Earth’s subsurface hosts enormous methane volumes trapped in geologic reservoirs, gas hydrates and permafrost, locally escaping the sediment at cold seeps to enter the hydrosphere/atmosphere.
Such environments are highly sensitive to climate change. Despite an increasing awareness about the positive feedback between global warming and methane seepage, the response of these complex and dynamic systems to climate change is still unclear due to complex geo/hydro/atmosphere interactions.
Fossil cold seeps, long-term observatory studies and modern examples form the foundations to understand the mutual dependences between climate and seepage, and to develop robust models to forecast future scenarios at the Earth-system scale. For this session, we welcome geologists, geophysicists, geochemists, biologists, model developers, and any others who have contributed to new case studies in modern and fossil hydrocarbon seeps in the marine and terrestrial environment, gas hydrate and permafrost settings, to describe both new methods/technologies and the scientific outcomes.

The session gathers geoscientific aspects such as dynamics, reactions, and environmental/health consequences of radioactive materials that are massively released accidentally (e.g., Chernobyl and Fukushima nuclear power plant accidents, wide fires, etc.) and by other human activities (e.g., nuclear tests).

The radioactive materials are known as polluting materials that are hazardous for human society, but are also ideal markers in understanding dynamics and physical/chemical/biological reactions chains in the environment. Thus, the radioactive contamination problem is multi-disciplinary. In fact, this topic involves regional and global transport and local reactions of radioactive materials through atmosphere, soil and water system, ocean, and organic and ecosystem, and its relations with human and non-human biota. The topic also involves hazard prediction and nowcast technology.

By combining 35 years (> halftime of Cesium 137) monitoring data after the Chernobyl Accident in 1986, 10 years dense measurement data by the most advanced instrumentation after the Fukushima Accident in 2011, and other events, we can improve our knowledgebase on the environmental behavior of radioactive materials and its environmental/biological impact. This should lead to improved monitoring systems in the future including emergency response systems, acute sampling/measurement methodology, and remediation schemes for any future nuclear accidents.


The following specific topics have traditionally been discussed:
(a) Atmospheric Science (emissions, transport, deposition, pollution);
(b) Hydrology (transport in surface and ground water system, soil-water interactions);
(c) Oceanology (transport, bio-system interaction);
(d) Soil System (transport, chemical interaction, transfer to organic system);
(e) Forestry;
(f) Natural Hazards (warning systems, health risk assessments, geophysical variability);
(g) Measurement Techniques (instrumentation, multipoint data measurements);
(h) Ecosystems (migration/decay of radionuclides).

The session consists of updated observations, new theoretical developments including simulations, and improved methods or tools which could improve observation and prediction capabilities during eventual future nuclear emergencies. New evaluations of existing tools, past nuclear contamination events and other data sets also welcome.

This session merges CL3.1.3 “Climate change and other drivers of environmental change: Developments, interlinkages and impacts in regional seas and coastal regions” focused on regional seas and coastal regions worldwide, and CL3.1.4 “Climate change in Mediterranean-type climate regions” focused on the Mediterranean-type climates, with a very similar scope: how climate change and other drivers affect these regions now and in the future.
Regional climate change interacts with many other man-made perturbations in both natural and anthropogenic coastal environments. Regional climate change is one of multiple drivers, which have a continuing impact on terrestrial, aquatic and socio-economic (resp. human) environments. These drivers interact with regional climate change in ways, which are not completely understood.
A Mediterranean-type climate is characterized by mild, wet winters and hot, dry summers as classified with the Koppen-Geiger approach that is well suited for identifying and analyzing the impacts of climate change on natural and anthropic ecosystems. Mediterranean climate regions (MCRs) are located in transitional midlatitude regions like the Mediterranean basin area, western coastal North America and small coastal areas of western South America, southern Africa and southern Australia. The transitional character with sharp spatial gradients makes them highly vulnerable to climate change. For all MCRs, the future holds high risks and uncertainty on issues like loss in biodiversity, increase in aridity, ecological change, requiring innovative approaches to climate adaptation and mitigation.
This session focuses on the connections and interrelations between climate change and other drivers of environmental change in MCRs, regional seas and coastal regions. It intends to strengthen the exchanges among the communities involved to better understand and share commonalities and differences and to provide an overview of the current state of knowledge of the complicated interplay of different factors affecting climate change. This exchange may help identify and prepare shared solutions and practices. Studies focused on physical (including extremes, teleconnections, hydrological cycle) and biogeochemical (including biodiversity) aspects of Mediterranean and other coastal climate regions, focusing on observed past changes, future climate projections, as well as related social aspects including indigenous knowledge in mitigating climate risks will be treated.

The interactions between aerosols, climate, and weather are among the large uncertainties of current atmospheric research. Mineral dust is an important natural source of aerosol with significant implications on radiation, cloud microphysics, atmospheric chemistry and the carbon cycle via the fertilization of marine and terrestrial ecosystems. In addition, properties of dust deposited in sediments and ice cores are important (paleo-)climate indicators.

This interdivisional session --building bridges between the EGU divisions CL, AS, SSP, BG and GM-- had its first edition in 2004 and it is open to contributions dealing with:

(1) measurements of all aspects of the dust cycle (emission, transport, deposition, size distribution, particle characteristics) with in situ and remote sensing techniques,

(2) numerical simulations of dust on global, regional, and local scales,

(3) meteorological conditions for dust storms, dust transport and deposition,

(4) interactions of dust with clouds and radiation,

(5) influence of dust on atmospheric chemistry,

(6) fertilization of ecosystems through dust deposition,

(7) any study using dust as a (paleo-)climate indicator, including sediment archives in loess, ice cores, lake sediments, ocean sediments and dunes.

We especially encourage the submission of papers that integrate different disciplines and/or address the modelling of past, present and future climates.

This session is linked to the Pan-Eurasian EXperiment (PEEX; www.atm.helsinki.fi/peex), a multi-disciplinary, -scale and -component climate change, air quality, environment and research infrastructure and capacity building programme. It is aimed at resolving major uncertainties in Earth system science and global sustainability issues concerning the Arctic, Northern Eurasia and China regions. This session aims to bring together researchers interested in (i) understanding environmental changes effecting in pristine and industrialized Pan-Eurasian environments (system understanding); (ii) determining relevant environmental, climatic, and other processes in Arctic-boreal regions (process understanding); (iii) the further development of the long-term, continuous and comprehensive ground-based, air/seaborne research infrastructures together with satellite data (observation component); (iv) to develop new datasets and archives of the continuous, comprehensive data flows in a joint manner (data component); (v) to implement validated and harmonized data products in models of appropriate spatio-temporal scales and topical focus (modeling component); (vi) to evaluate impact on society though assessment, scenarios, services, innovations and new technologies (society component).
List of topics:
• Ground-based and satellite observations and datasets for atmospheric composition in Northern Eurasia and China
• Impacts on environment, ecosystems, human health due to atmospheric transport, dispersion, deposition and chemical transformations of air pollutants in Arctic-boreal regions
• New approaches and methods on measurements and modelling in Arctic conditions;
• Improvements in natural and anthropogenic emission inventories for Arctic-boreal regions
• Physical, chemical and biological processes in a northern context
• Aerosol formation-growth, aerosol-cloud-climate interactions, radiative forcing, feedbacks in Arctic, Siberia, China;
• Short lived pollutants and climate forcers, permafrost, forest fires effects
• Carbon dioxide and methane, ecosystem carbon cycle
• Socio-economical changes in Northern Eurasia and China regions.
PEEX session is co-organized with the Digital Belt and Road Program (DBAR), abstracts welcome on topics:
• Big Earth Data approaches on facilitating synergy between DBAR activities & PEEX multi-disciplinary regime
• Understanding and remote connection of last decades changes of environment over High Asia and Arctic regions, both land and ocean.

Biogeomorphology addresses the two-way interaction between abiotic and biotic elements that shape landscapes at various spatio-temporal scales. Yet, developing theory, methods and quantifying processes across the abiotic/biotic interface remains challenging. This is partly due to the interdisciplinarity of biogeomorphology, integrating concepts from biology, climatology, engineering, Earth surface science and geology (amongst other disciplines). Although more and more biogeomorphic feedbacks are being investigated, understood, and applied in practice, many of these remain poorly studied and understood. However, a better understanding of abiotic-biotic interaction across scales is urgently needed for a more holistic understanding of the Earth surface as well as ecological dynamics for sustainable management, and climate change mitigation and adaptation.

This session aims to bring together geoscientists, soil scientists and biologists working at different spatial and temporal scales on how climate, tectonics, soils, flora and fauna affect landscape development, erosion control and thus form the Earth’s surface. Thus, we provide a discussion platform for all aspects of biogeomorphology, including fundamental science and applied studies. Topics may include, but are not limited to, biogeomorphic processes, rates and feedbacks for biotic and/or abiotic processes, climate-tectonics-earth surface dynamics, and biogeomorphology as a tool to sustainably manage natural systems and hazards. We encourage everyone interested in biogeomorphology to contribute to the session to further strengthen the community and stimulate discussion and collaboration across scales.

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 (CHONS …) 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).

Stable isotopes and other novel tracers help to identify and quantify biological, chemical and physical mechanisms that drive Earth's biogeochemical cycling, atmospheric processes and biosphere-atmosphere exchange. Recent developments in analytical measurement techniques now offer the opportunity to investigate these tracers at unprecedented temporal and spatial resolution and precision.

This session is open to contributions from diverse fields where stable isotopes of light elements (e.g. C, H, O, N) and other novel tracers, such as carbonyl sulfide, clumped isotopes and non-mass dependent fractionation processes are used to identify and quantify biological, chemical and physical processes. We welcome contributions from field and laboratory experiments, the latest instrument developments as well as theoretical and modelling studies.

Topics addressed in this session include:
- Stable isotopes of carbon dioxide (CO2), water (H2O), methane (CH4), nitrous oxide (N2O), carbonyl sulfide (COS) and any other trace gases
- Novel tracers and biological analogues, such as COS
- Polyisotopocules ("clumped isotopes")
- Intramolecular stable isotope distributions ("isotopomer abundances")
- Analytical, method and modelling developments
- Flux measurements
- Quantification of isotope effects
- Non-mass dependent isotopic fractionation and related isotope anomalies

Observations from aircraft, remotely piloted aircraft systems (RPAS/UAV/UAS) and balloons are an important means to obtain a broad view of processes within the Earth environment during measurement campaigns. The range of available instruments enables a broad and flexible range of applications. It includes sensors for meteorological parameters, trace gases and cloud/aerosol particles and more complex systems like high spectral resolution lidar, hyperspectral imaging at wavelengths from the visible to thermal infra-red, solar-induced fluorescence and synthetic aperture radar. The use of small state-of-the-art instruments, the combination of more and more complex sets of instruments with improved accuracy and data acquisition speed enables more complex campaign strategies even on small aircraft, balloons or RPAS.
Applications include atmospheric parameters, structural and functional properties of vegetation, glaciological processes, sea ice and iceberg studies, soil and minerals and dissolved or suspended matter in inland water and the ocean. Ground based systems and satellites are key information sources to complement airborne datasets and a comprehensive view of the observed system is often obtained by combining all three. Aircraft and balloon operations depend on weather conditions either to obtain the atmospheric phenomenon of interest or the required surface-viewing conditions and so require detailed planning. They provide large horizontal and vertical coverage with adaptable temporal sampling. Future satellite instruments can be tested using airborne platforms during their development. The validation of operational satellite systems and applications using airborne measurements has come increasingly into focus with the European Copernicus program in recent years.
This session will bring together aircraft, balloon and RPAS operators and researchers to present:
• an overview of the current status of environmental research focusing on the use of airborne platforms
• recent observation campaigns and their outcomes
• multi-aircraft/balloon/RPAS and multi-RI campaigns
• using airborne and ground-based RI to complement satellite data, including cal/val campaigns
• identifying and closing capability gaps
• contributions of airborne measurements to modelling activities
• airborne platforms to reduce the environmental footprint of alternative observation strategies
• airborne instruments, developments and observations
• future plans involving airborne research

Soil organic matter (SOM) contains a vast range of diverse organic structures, and also a living component (microorganisms) with various residence times that define the central role SOM plays in fundamental physico-chemical and biological processes in the soil. With human activities severely affecting SOM dynamics (through inappropriate agricultural practices, erosion, forest fires, climate change), a better understanding of SOM transformation is urgently needed as this has further implications for carbon (C), nitrogen (N) and phosphorus (P) cycling and biogeochemical processes affecting global CO2 emissions. Detailed analyses of SOM composition can highlight the role of selective preservation mechanisms and sources of SOM, for example, and how these are modified and influenced by physical and chemical interactions.
To trace SOM sources and the composition of microbial communities a broad set of biomarkers is used: lignin compounds (C sources from plant communities), cutin and suberin (above- vs belowground plant biomass), non-cellulose sugars (plant vs microbial C), DNA (microbial community composition), phospholipid fatty acids (living microbial groups), ergosterol (fungal biomass), amino sugars (microbial necromass and its sources) are just a few examples. Coupling analysis of these biomarkers with 13C/14C/15N/33P/18O labeling allows tracing these elements through the microbial food web and the soil element cycles. It, thus, reveals turnover of organics and their stabilization in SOM, C, N and P recycling in microbial biomass, growth rates of bacteria and fungi, and microbial metabolic pathways.
We encourage the submission of studies (especially from early-career students) employing new methods or applications of identification and quantification of biomarkers to study: i) the fate and turnover of organic and inorganic inputs in soil (from uptake and utilization by microorganisms to stabilization in SOM), ii) the mechanisms and sources of SOM formation and its turnover, and iii) to link microbial recycling of different elements (C, N and, P) from fresh organic material or during reworking SOM. Field and laboratory studies focused on the effects of management practices, climate change, environmental conditions, soil properties are highly welcome. We also encourage contributors to present and discuss analytical challenges that remain due to environmental and analytical uncertainty.

Soil pollution is a worldwide problem, which can result in a negative impact in (terrestrial) ecosystems, surface and groundwater, and the food chain. According to the European Commission, there are around 2.8 million soil pollution events contributing to soil pollution. Of these, 25 % have been identified and registered, but only 5% need mitigation strategies. In order to address soil pollution and develop preventive and mitigation strategies, it is necessary to invest in (i) the identification and characterization of these sites, from contaminant identification to ecosystem characterisation, and (ii) the identification of potential solutions. This requires linking new strategies (e.g. machine learning, artificial intelligence, digital data mapping) with natural solutions (e.g. soil-microorganisms-root-plant interaction). We welcome our colleagues to present their latest and ongoing findings and look forward to establishing new partnerships to create holist strategies that can help to prevent, assess and mitigate soil pollution consistently and swiftly.

This interdisciplinary session welcomes contributions on novel conceptual and/or methodological approaches and methods for the analysis and statistical-dynamical modeling of observational as well as model time series from all geoscientific disciplines.
Methods to be discussed include, but are not limited to linear and nonlinear methods of time series analysis. time-frequency methods, statistical inference for nonlinear time series, including empirical inference of causal linkages from multivariate data, nonlinear statistical decomposition and related techniques for multivariate and spatio-temporal data, nonlinear correlation analysis and synchronisation, surrogate data techniques, filtering approaches and nonlinear methods of noise reduction, artificial intelligence and machine learning based analysis and prediction for univariate and multivariate time series.
Contributions on methodological developments and applications to problems across all geoscientific disciplines are equally encouraged. We particularly aim at fostering a transfer of new methodological data analysis and modeling concepts among different fields of the geosciences.

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.

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

Meet editors of internationally renowned journals in geo- and biogeoscience and gain exclusive insights into the publishing process. After a short introduction into some basics, we will start exploring various facets of academic publishing with short talks given by the editors on

- What are the duties and roles of editors, authors and reviewers?
- How to choose a suitable journal for your manuscript and what is important for early career authors?
- How can early career scientists get involved in successful peer-reviewing?
- What is important for appropriate peer-reviewing?
- What are ethical aspects and responsibilities of publishing?

Together with the audience and the editors, we will have an open discussion of the key steps and factors shaping the publication process of a manuscript. This short course aims to provide early career scientists across several EGU divisions (e.g. AS, BG, CL, GM, NH, SSP and SSS) the opportunity of using first hand answers of experienced editors of international journals to successfully publish their manuscripts and get aware of the potentials and pitfalls in academic publishing.

Citizen science (the involvement of the public in scientific processes) is gaining momentum across multiple disciplines, increasing multi-scale data production on Earth Sciences that is extending the frontiers of knowledge. Successful participatory science enterprises and citizen observatories can potentially be scaled-up in order to contribute to larger policy strategies and actions (e.g. the European Earth Observation monitoring systems), for example to be integrated in GEOSS and Copernicus. Making credible contributions to science can empower citizens to actively participate as citizen stewards in decision making, helping to bridge scientific disciplines and promote vibrant, liveable and sustainable environments for inhabitants across rural and urban localities.
Often, citizen science is seen in the context of Open Science, which is a broad movement embracing Open Data, Open Technology, Open Access, Open Educational Resources, Open Source, Open Methodology, and Open Peer Review. Before 2003, the term Open Access was related only to free access to peer-reviewed literature (e.g., Budapest Open Access Initiative, 2002). In 2003 and during the “Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities”, the definition was considered to have a wider scope that includes raw research data, metadata, source materials, and scholarly multimedia material. Increasingly, access to research data has become a core issue in the advance of science. Both open science and citizen science pose great challenges for researchers to facilitate effective participatory science, yet they are of critical importance to modern research and decision-makers.

We want to ask and find answers to the following questions:
Which approaches and tools can be used in Earth and planetary observation?
What are the biggest challenges in bridging between scientific disciplines and how to overcome them?
What kind of participatory citizen scientist involvement (e.g. how are citizen scientists involved in research, which kind of groups are involved) and open science strategies exist?
How to ensure transparency in project results and analyses?
What kind of critical perspectives on the limitations, challenges, and ethical considerations exist?
How can citizen science and open science approaches and initiatives be supported on different levels (e.g. institutional, organizational, national)?

In this crossover session, we invite studies on the latest advancements in analytical and experimental techniques from all relevant fields dealing with geochemical processes or applying chemical/isotope data to assess the dynamics in geological systems. Relevant are all-new achievements of techniques more or less established in Earth sciences. Moreover, new techniques or experiments brand-new to Earth sciences are of particular interest. Techniques are welcome from mass spectrometry, photon/electron-based spectroscopy, including microscopy and measurements under various conditions (ambient to non-ambient) and spatial resolutions. The overarching breadth of this session will foster the exchange between the communities.

Recent advances in image collection, e.g. using unoccupied aerial vehicles (UAVs), and topographic measurements, e.g. using terrestrial or airborne LiDAR, are providing an unprecedented insight into landscape and process characterization in geosciences. In parallel, historical data including terrestrial, aerial, and satellite photos as well as historical digital elevation models (DEMs), can extend high-resolution time series and offer exciting potential to distinguish anthropogenic from natural causes of environmental change and to reconstruct the long-term evolution of the surface from local to regional scale.
For both historic and contemporary scenarios, the rise of techniques with ‘structure from motion’ (SfM) processing has democratized data processing and offers a new measurement paradigm to geoscientists. Photogrammetric and remote sensing data are now available on spatial scales from millimetres to kilometres and over durations of single events to lasting time series (e.g. from sub-second to decadal-duration time-lapse), allowing the evaluation of event magnitude and frequency interrelationships.
The session welcomes contributions from a broad range of geoscience disciplines such as geomorphology, cryosphere, volcanology, hydrology, bio-geosciences, and geology, addressing methodological and applied studies. Our goal is to create a diversified and interdisciplinary session to explore the potential, limitations, and challenges of topographic and orthoimage datasets for the reconstruction and interpretation of past and present 2D and 3D changes in different environments and processes. We further encourage contributions describing workflows that optimize data acquisition and processing to guarantee acceptable accuracies and to automate data application (e.g. geomorphic feature detection and tracking), and field-based experimental studies using novel multi-instrument and multi-scale methodologies. This session invites contributions on the state of the art and the latest developments in i) modern photogrammetric and topographic measurements, ii) remote sensing techniques as well as applications, iii) time-series processing and analysis, and iv) modelling and data processing tools, for instance, using machine learning approaches.

The main goal of this short course is to provide an introduction into the basic concepts of numerical modelling of solid Earth processes in the Earth’s crust and mantle in a non-technical manner. We discuss the building blocks of a numerical code and how to set up a model to study geodynamic problems. Emphasis is put on best practices and their implementations including code verification, model validation, internal consistency checks, and software and data management. 

The short course introduces the following topics:
(1) The physical model, including the conservation and constitutive equations
(2) The numerical model, including numerical methods, discretisation, and kinematical descriptions
(3) Code verification, including benchmarking
(4) Model design, including modelling philosophies
(5) Model validation and subsequent analysis
(6) Communication of modelling results and effective software, data, and resource management

Armed with the knowledge of a typical numerical modelling workflow, participants will be better able to critically assess geodynamic numerical modelling papers and know how to start with numerical modelling.

This short course is run by early career geodynamicists. It is aimed at everyone who is interested in, but not necessarily experienced with, geodynamic numerical models; in particular early career scientists (BSc, MSc, PhD students and postdocs) and people who are new to the field of geodynamic modelling.

Research, especially for early career scientists (ECS), starts with the spark of an idea and is then often challenged by empirical or methodological road bumps and seemingly dead ends. In Earth Science research, we face a diverse range of challenges, including (1) access difficulties, whether for field sites, equipment or data, (2) problems of temporal and spatial scaling and extrapolation and (3) a lack of methods, theory or knowledge or (4) every day live challenges as a scientist. As part of SC4 we want to address some of those 'problems'. In the discussion of these challenges we seek to find possible solutions, suggest new research approaches and methods, and encourage further networking amongst early career scientists at future international conferences.

We will start the session at this year's hybrid meeting with 2 minute ‘pop-up’ presentations outlining some challenges. These pop-ups are followed by chaired and structured outbreak group discussions. There will be the option to join these discussions both in-person and virtually. To wrap up the session, solutions and suggestions from each group are presented to the whole session in a final discussion. This short course lives by your input, so participants are expected to actively engage to crowd solve the presented challenges. To ensure that people are able to have a safe and open space to share their ideas, we ask you to join for the whole session. You can get an idea of past crowd-solving sessions, both in-person and online, from our 2019 (EGU blog) and 2021 (EGU blog) blog posts, see links below.

If you have a 'problem' you would like to discuss in the networking session with us, please send a short statement (3-4 sentences) of your idea or challenge and your motivation for solving it to us, by March 1st, 2022. We expect a non-hierarchic, respectful and constructive environment for the discussions, which will hopefully encourage the participants to identify and approach problems faced by early-career scientists.

EGU 2019: https://blogs.egu.eu/geolog/2019/06/05/challenging-challenges-in-earth-science-research-at-the-egu-general-assembly/

vEGU 2021: https://blogs.egu.eu/geolog/2021/07/02/crowd-solutions-to-challenges-in-earth-sciences/

During the recent years, it has become more and more obvious that soil structure plays a fundamental role in regulating processes in soils. As soil structures are hierarchical, complex and highly variable, studies involving soil structures require a relatively large number of replicate samples. Three-dimensional X-ray imaging provides an excellent tool to map out soil structure, but image analyses are still time intensive and require experience. This limits the number of X-ray images, and thus replicate samples that can be analyzed within reasonable time scales. SoilJ is an open-source and free plugin for the open-source image processing software ImageJ. It is tailor-made for the analyses X-ray images of soil and aims at automatizing the necessary image processing and analyses steps. This course gives a short introduction into X-ray image processing and analyses in general and specifically with SoilJ, provides an overview about SoilJ functionalities and offers guidance for researchers interested in participating in developing their own plugins.

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 a challenge.

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.

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, 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.

Thus, our current understanding of the environmental controls on vegetation dynamics and properties, and, in turn, their impact on carbon stocks in biomass and soils, is limited. The behaviour of vegetation models regarding many of the processes mentioned above remains under-constrained at scales from landscape to global. This 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, accelerated background tree mortality or more frequent and more severe disturbance events (e.g. drought, fire, insect outbreaks) might turn vegetation into carbon sources. Likewise, understanding how these shifts in dynamics will influence forest composition is crucial for long-term carbon cycle projections.

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.

Biogenic volatile organic compounds (bVOCs) are global chemical signatures of life. bVOCs comprise chemically diverse gaseous compounds of biological origin and are emitted from and consumed in terrestrial ecosystems. We consider biological sources and sinks being mainly plants and soil life, especially the microbiota. bVOCs are receiving an increasing scientific interest since breakthroughs in analytics of compounds but also of plants and microbiota facilitate an integrative understanding.
bVOCs have various environmental functions. Some impact on the oxidative capacity of the troposphere, stratospheric ozone destruction, and contribute to aerosol formation. Others are involved in chemical signaling between plants, animals and microbes in terrestrial ecosystems and hence, connect organisms’ activities and behaviors beyond the canonical trophic foodweb theory. In the era of the anthropocene, land use and associated human forces alter bVOC flux dynamics by changing ecosystems and their properties.
Understanding bVOCs fluxes in and from terrestrial ecosystems has two conceptual dimensions. (a) They are ecological interaction signals and thus, are affecting ecological interactions and ecosystem functioning - which includes plant production in agriculture - and (b) they are relevant for atmospheric chemistry and thus land-atmosphere interactions. Both dimensions are inherently intertwined and can be seen as two sides of the same coin.
We would like to merge both dimensions in one single session at the EGU Biogeosciences Division to trigger discussions on future research perspectives - e.g. how to quantitatively determine and/or predict bVOC fluxes by considering interactions of biological actors. Also novel insights in the topic, and methodological developments and new approaches are highly welcomed.

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. These model projections constrain the current mean state of the terrestrial biosphere, but they provide limited information on the sensitivity of ecophysiological, biogeochemical, and hydrological processes to environmental changes. Observational and ecosystem manipulation studies (e.g., Free-Air Carbon Dioxide Enrichment (FACE), nutrient addition or warming experiments) can complement modelling studies with unique insights and inform model development and evaluation.

This session focuses on how ecosystem processes respond to changes in CO2 concentration, warming, altered precipitation patterns, water and nutrient availability. It aims at fostering the interaction between the experimental and modelling communities by advancing the use of observational and experimental data for model evaluation and calibration. We encourage contributions from syntheses of multiple experiments, model intercomparisons and evaluations against ecosystem manipulation experiments, pre-experimental modelling, or the use of observations from "natural experiments". Contributions may span a range of scales and scopes, including plant ecophysiology, soil organic matter dynamics, soil microbial activity, nutrient cycling, plant-soil interactions, or ecosystem dynamics.

Gross photosynthetic CO2 uptake is the single largest component of the global carbon cycle and a crucial variable for monitoring and understanding global biogeochemical cycles and fundamental ecosystem services. Nowadays routine measurements of the net biosphere-atmosphere CO2 exchange are conducted at the ecosystem scale in a large variety of ecosystem types across the globe. Gross photosynthetic and ecosystem respiratory fluxes are then typically inferred from the net CO2 exchange and used for benchmarking of terrestrial biosphere models or as backbones for upscaling exercises. Uncertainty in the responses of photosynthesis and respiration to the climate and environmental conditions is a major source of uncertainty in predictions of ecosystem-atmosphere feedbacks under climate change. On the other hand, transpiration estimates both at ecosystem to global scales are highly uncertain with estimates ranging from 20 to 90 % of total evapotranspiration. The most important bottleneck to narrow down the uncertainty in transpiration estimates is the fact that direct measurements of transpiration are uncertain and techniques like eddy covariance measure only the total evapotranspiration.
During the last decade, technological developments in field spectroscopy, including remote and proximal sensing of sun-induced fluorescence, as well as in isotope flux measurements and quantum cascade lasers have enabled alternative approaches for constraining ecosystem-scale photosynthesis, respiration and transpiration. On the other hand, a variety of approaches have been developed to directly assess the gross fluxes of CO2 and transpiration by using both process based and empirical models, and machine learning techniques.
In this session, we aim at reviewing recent progress made with novel approaches of constraining ecosystem gross photosynthesis, respiration and transpiration and at discussing their weaknesses and future steps required to reduce the uncertainty of present-day estimates. To this end, we are seeking contributions that use emerging constrains to improve the ability to quantify respiration and photosynthesis processes, transpiration and water use efficiency, at scales from leaf to ecosystem and global. Particularly welcome are studies reporting advancements and new developments in CO2 and evapotranspiration flux partitioning from eddy covariance data, the use of carbonyl sulfide, stable isotopes approaches and sun-induced fluorescence.

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.

Wide-spread permafrost thaw is expected to amplify the release of previously frozen material from terrestrial into aquatic systems: rivers, lakes, groundwater and oceans. Current projections include changes in precipitation patterns, active layer drainage and leaching, increased thermokarst lake formation, as well as increased coastal and river bank erosion that are further enhanced by rising water temperatures, river discharge and wave action. In addition, subsea permafrost that formed under terrestrial conditions but was later inundated might be rapidly thawing on Arctic Ocean shelves. These processes are expected to substantially alter the biogeochemical cycling of carbon but also of other elements in the permafrost area.
This session invites contributions on the mobilization of terrestrial matter to aquatic systems in the permafrost domain, as well as its transport, degradation and potential interaction with autochthonous, aquatic matter. We encourage submissions focusing on organic and inorganic carbon as well as on other elements such as nitrogen, phosphorus, silica, iron, mercury and others, from all parts of the global permafrost area including mountain, inland, coastal and subsea permafrost, on all spatial scales, in the contemporary system but also in the past and future, based on field, laboratory and modelling work.

Eco-evolutionary optimality (EEO) theory invokes the power of natural selection to eliminate uncompetitive trait combinations, and thereby shape predictable, general patterns in vegetation structure and composition. Although the implementation of process-based representations derived from EEO principles in vegetation and land-surface models is a relatively recent phenomenon, it is already yielding considerable improvements to our ability to simulate vegetation responses to changing climate and environmental conditions. For example, hypotheses derived from EEO principles are proving helpful in developing parsimonious representations of leaf-level processes such as photosynthesis and primary production, dark respiration, and stomatal behaviour. EEO approaches can also be applied to at whole plant and community levels, providing simple ways of representing plant interactions and ecosystem dynamics. Comparisons of EEO-based predictions against experimental data and field and remote-sensing observations provide a way of evaluating the robustness of the hypotheses, as well as discriminating between alternative EEO hypotheses.
This session is designed to bring together scientists applying EEO approaches to modelling plant behaviour from cellular to community scales, experimentalists and observationalists developing data sets that can be used to evaluate EEO hypotheses, and vegetation and land-surface modellers implementing EEO approaches in existing model frameworks. The session will explore the current state-of-the-art, as well as ways to move EEO-based approaches forward. The key objective is to bring together researchers from different communities working on EEO principles, promoting scientific exchanges that are much needed to develop robust, reliable and realistic next-generation Earth System Models.

A transition towards sustainable agriculture is needed to ensure that both present and future societies will be food secure. Current agricultural productivity is already challenged by several factors, such as climate change, availability and accessibility of water and other inputs, socio-economic conditions, and changing and increased demand for agricultural products. Agriculture is also expected to contribute to climate change mitigation, to minimize pollution of the environment, and to preserve biodiversity.
Assessing all these requires studying alternative land management at local to global scales and to assess agricultural production systems rather than individual products.
This session will focus on the modeling of any part of or entire agricultural systems under global change, addressing challenges in adaptation to and mitigation of climate change, sustainable intensification and environmental impacts of agricultural production. We welcome contributions on methods and data, assessments of climate impacts and adaptation options, environmental impacts, GHG mitigation and economic evaluations.

Global, collaborative research has the potential to address substantial knowledge gaps in peatland science. The integration of insights across individual study sites and disciplines, including those from biogeosciences, hydrology, and global environmental change, can help resolve key unknowns regarding the response of global peatlands to projected disturbances. We are more technologically capable than ever to conduct this much needed collaborative work, and today’s early career researchers will play a pivotal role in shaping the future of peatland science. The goal of this session is to bring together early career peatland researchers (within 7 years post PhD) across scientific fields to emphasize the commonalities and differences in our findings across geographical regions and peatland type. We encourage interdisciplinary submissions comparing processes and spatio-temporal scales in peatlands worldwide and/or studies with management implications, but also welcome localized and methodologically specific studies which have broader implications.

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 forestry practices 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.

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 and adaptation strategies. Much attention has been devoted to the biogeochemical impacts of LULCC, yet there is an increasing awareness that the biogeophysical mechanisms (e.g. changes in surface properties such as albedo, roughness and evapotranspiration) should also be considered in climate change assessments of LULCC impacts on weather and climate. However, characterizing biogeophysical land-climate interactions remains challenging due to their complexity. If a cooling or a warming signal emerges depends on which of the biogeophysical processes dominates and on the size and pattern of the LULCC perturbation. 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. This session invites studies that improve our general understanding of climate perturbations connected to LULCC from both biogeophysical and biogeochemical standpoints, and particularly those focusing on their intersection. This includes studies focusing on LULCC that can inform land-based climate mitigation and adaptation policies. Both observation-based and model-based analyses at local to global scales are welcome.

From pole to pole, peatlands contain up to 30% of the world’s soil carbon pool, illustrating their role in the global carbon cycle. Currently peatlands are under various pressures such as changing climate, land-use or nutrient loading with unknown consequences for their functioning as carbon sinks and stores and the uptake or release of the greenhouse gasses carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Simultaneously, increasing amount of restoration activities, aiming to return peatlands back to their original state are ongoing. It is, however, not clear how the carbon reservoir will react to these pressures and how resilient these ecosystems are. This session will focus on the observed or predicted changes on the biogeochemistry at peatlands, caused by climate change, nutrient loading or land-use. We invite studies concentrating, for example, on the effects of climate change on GHG flux or nutrient dynamics on pristine and managed peatlands, impact of drainage or restoration and subsequent vegetation succession on biogeochemistry, atmosphere-biosphere interaction, or studies on carbon stock changes demonstrating the impact of land-use or climate change. Experimental and modelling studies of both high- and low latitude peatlands are welcomed.

The health of plant natural communities, crop and forestry systems is constrained by increasing occurrence of natural and anthropogenic disturbances. Phenomena such as climate extremes, drought, flooding, insect outbreaks and wildfire are affecting the productivity of plant communities often leading to decline and mortality, forest dieback and alterations in distribution and productivity of the most important crops worldwide.
The mechanisms of plant decline, often related to hydraulic failure and reduction in photosynthesis, have not been fully unravelled and linked to specific measurable traits, leading to a need for multiple proxies.
Understanding how traits and their plasticity connect with the mechanisms determining plant health and species mortality is a key requisite for i) predicting plant population dynamics and climate change-driven changes in community composition in natural ecosystems and ii) forecasting possible changes in plant productivity in crop systems to manage cultivation factors to mitigate the climate change effects. This also applies to controlled environment agriculture systems for resource use optimization for sustainability goals, and to crop production in Space for exploration.
This session provides a forum on the role of functional traits (e.g., specific leaf area and anatomy, 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 throughout an individual plant’s life 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 ecosystems. Such information will be useful as input for dynamic global vegetation and crop models supporting international policy for sustainability.

A robust representation of the terrestrial carbon and water cycles requires fundamental understanding of biosphere-atmosphere interactions, particularly in a changing climate. Multiple processes determine how mass and energy exchanges scale from the leaf, to the whole plant, to the ecosystem, and eventually to the globe. Earth system models continue to evolve and incorporate increasingly complex processes across these scales, without however, reducing the uncertainties. Challenge remains to robustly formulate mechanistic underpinnings of biogeochemical processes across scales. The increasing amount 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 Earth observation from space, are now opening new opportunities to tackle these challenges.

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 modeling strategies. In addition to empirical multi-scale observations of carbon and water fluxes, we invite research that explore data-driven diagnostics and constraints for model evaluation (e.g., Emergent Constraints), data-driven parameterizations in mechanistic models (e.g., ESMs) and other developments of data-driven/hybrid modelling strategies (i.e., seamless fusion of data-driven approaches and mechanistic models) for an integrated understanding of carbon and water fluxes across scales.

Exchange of greenhouse gases (GHGs) such as methane (CH4) and nitrous oxide (N2O) in forest ecosystems has traditionally focused on gas flux measurements from soil or between biosphere and atmosphere in the surface layer only. However, it has become evident that trees may play an important role in the net exchange of these GHGs in forests. Trees can contribute to ecosystem exchange by uptake and transport of soil-produced CH4 and N2O to the atmosphere, in-situ production and consumption of both gases in plant tissues, and alternation of carbon- and nitrogen-turn-over in adjacent soil. However, the contribution of these individual processes to the net ecosystem GHGs exchange is still unclear and seems to depend on many aspects as tree species, forest ecosystem type, environmental parameters and seasonal dynamics. Interactions between soil, vegetation and the atmosphere exert a crucial role controlling the global budget of these gases.
This session seeks to bring together scientists working on the exchange of CH4 and N2O in forest ecosystems at any relevant scale, and from the full climatic and hydrological forest range. We therefore welcome contributions on (i) production and consumption processes in soils and plant tissues; (ii) gas transport processes in soil-tree-atmosphere continuum; (iii) gas flux measurements on the forest floor, cryptogams, tree stems or at leaf and canopy level; (iv) micrometeorological measurements using flux towers, satellite, or modelling approaches that seek to integrate our understanding of CH4 and N2O exchange in forest ecosystems.

The tropics play a critical role in regulating the global climate system through the exchange of greenhouse gases (GHG), water, and energy between soil, vegetation and the atmosphere. Tropical forests, wetlands, and grasslands store sizeable amounts of carbon, and provide other important ecosystem services such as wood, foods, and biodiversity. Historic and recent human activities have, however, resulted in intensive transformation of these ecosystems impacting the cycling of nutrients, carbon, water, and energy. Increasing tropical forest degradation and loss, peatland drainage, grassland conversion, and agriculture expansion to meet demands for timber and food releases stored carbon and drives growing GHG emissions in the tropics, an issue of increasing international concern. Preventing land-use change and restoring degraded tropical ecosystems offers the possibility to mitigate anthropogenic GHG emissions, but estimates of the potential GHG benefits of such activities are overall poorly constrained.

Here we invite contributions that provide insights on how land-use, land-use change, and ecosystem conservation and restoration influence ecohydrology, biogeochemical cycles, and GHG emissions (CO2, CH4, N2O) in tropical ecosystems at plot, landscape, and continental scale. Examples include nitrogen and carbon cycle in the soil and vegetation, the exchange of GHG between soil and atmosphere as well as vegetation and atmosphere, changes in the energy balance, impacts on the water cycle, scaling issues from plots to country to continent as well as the influence of management activities (e.g. fertilization, drainage, etc. ) on GHG fluxes. The aim of this session is to provide a synthesis of knowledge on exchanges of water and energy as well as biogeochemical processes influencing carbon storage and GHG emissions from tropical ecosystems that are degraded, converted, or restored. Experimental studies (e.g., chamber or eddy covariance flux measurements, laboratory based, etc.), inventories, as well as remote sensing or modelling studies are welcome, and we encourage contributions that compare GHG emissions in pristine and disturbed ecosystems.

Managed agricultural ecosystems (grassland and cropland) are an important source and/or sink for various gases in the atmosphere including greenhouse gases (GHG) and reactive trace gases like ammonia. 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.
While process-based models are designed to combine all relevant effects on gas emissions, some processes like denitrification (as a source of N2 and N2O) have rarely been validated due to the lack of suitable data-sets, and thus results of their application on site and regional scales are still highly uncertain.
The session addresses experimentalists and modelers working on carbon and nitrogen cycling processes and related gas fluxes on plot, field, landscape, and regional scale.
We invite contributions from the following fields: methodical advances in measuring and modelling of soil processes; measurements of gas fluxes under field or field-like conditions with a focus on controlling factors; method comparisons including micrometeorological and chamber techniques as well as tracer and isotope (or isotopologue) approaches or other novel methods; process-based modelling at various scales; and the linking of soil processes and emissions to microbial community parameters.

Climate change has already started to affect dynamic feedbacks between plant, soil, and microbial communities and thus strongly influences terrestrial biogeochemical cycling. In this session we address the questions: What is the impact of changing environmental conditions on the plant-soil system, and the resulting effects on soil biogeochemistry? And how do we represent soils in (global) models and upscale experimental data using process-based understanding of the controls on biogeochemical cycles? In this session we seek contributions addressing how biogeochemical cycles in soils vary across gradients in climate, vegetation, and soil properties, and how they may respond to future changes.

We invite contributions from manipulative field experiments, observations in natural-climate gradients, and modelling studies that explore climate change impacts on plant-soil interactions, biogeochemical cycling of C, N, P, microbial diversity and decomposition processes, and deep -soil biogeochemistry. Researchers are encouraged to present their empirical and/or modeling studies addressing soil dynamics along geochemical and climatic gradients. 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.

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.

This session aims to bring together scientists interested in advancing our fundamental understanding of vegetation and whole-ecosystem processes. 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.

With the multitude of functions and services simultaneously and increasingly required from forests, it is crucial to improve our understanding of these complex ecosystems, also in light of the potential alterations introduced by different global change drivers, mostly due to anthropogenic activities.
Natural disturbances are a primary driver of forest dynamics, 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. 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.
In this session, we invite contributions from all fields in order to promote knowledge on forest 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. This session addresses in particular the potentials and limitations of various remote sensing applications in forestry, with a focus on the identification and integration of different methodologies and techniques from different sensors and in-situ data for providing qualitative and quantities forest information.
A key development in remote sensing has been the increased availability of data with very high temporal, spatial and spectral resolution. In the last decades, several types of remote sensing data, including optical, multispectral, radar, LiDAR from terrestrial, UAV, aerial and satellite platforms, have been used to detect, classify, evaluate and measure the earth surface, including different vegetation cover and forest structure. For the forest sector, such information allows efficient quantification of the state and monitoring of changes over time and space, in support of sustainable forest management, forest and carbon inventory or for monitoring forest health and their disturbances.
However, to meet the various information requirements, different data sources should be adopted according to the application, the level of detail required and the extension of the area under study. The integration of in-situ measurements with satellite/airborne/UAV imagery, Structure from Motion, LiDAR and geo-information systems offers new possibilities, especially for interpretation, mapping and measuring of forest parameters and will be a challenge for future research and application.

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. 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. Implementation and efficiency of management practices depends not only on hydrogeology and climate but also on other regional factors. Therefore, we hope to host contributions from different geographical regions where peatlands are important including boreal, temperate and tropical peatlands.

The ecological stability, soil degradation, and hydrological extremes are the main driving elements and powerful tools associated with climate change on reducing or increasing the acceleration of climate change.
Climate change is a natural process, but the latest scientific research proves that it is significantly accelerated by human activity. Adequate steps can be taken by humans (for instance land use/land cover changes) in order to reduce the risks and consequences of the effects of climate change. Despite this knowledge, which is well known, progress is still slow, and the negative consequences prevail over the positive remedies.
The session should reflect, discuss, and share scientific knowledge on a local and regional scale with the aim to increase innovative knowledge thanks to multidisciplinary links at national, international, and global levels.
This session is open within a wide range of relevant scientific topics as follows:
• hydrological extremes as one of the main impacts of climate change;
• lack of precipitation or extreme precipitation - how to reduce and decrease these extremes by adequate measures;
• the connection between deteriorating ecological stability and climate change;
• new methods and procedures for reducing existing manifestations 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);
• proposal of measures to prevent the occurrence of the above-mentioned impacts;
• the sustainability of management practices, the importance of appropriate land use management as the main tool for preventing degradation processes, floods, and droughts, improving the condition of forest ecosystems in order to increase the overall character of the landscape.

It is wildly accepted that the functions of soil are intimately linked to its structure and state of aggregation. Water retention characteristics, ventilation, fluids-flow, and transport of mobile material - from the solutes and colloids to suspended particles - depends intricately on the properties of the void network structure and the composition and properties of the solid-fluid interfaces therein. Extent and rates of organic matter storage, nutrient supply, contaminant retardation, but also microbial colonization, root penetration and hyphae exploration patterns are part of a complicated feedback loop that not only creates structure but results in its change in space and time. Processes and mechanisms that result in structure formation and dynamics in soil are intensively studied and vividly debated: In particular the role of aggregates and aggregation is discussed intensively. With the advent of sophisticated spectroscopic, microscopic, and tomographic techniques that enable to study structure, composition and interface properties at the submicron scale even down to the atomic scale, testing hypothesis on the co-evolution of structure, properties and emerging function on soils from the atom to the pedon scale is rapidly progressing. In particular if techniques exploring void-interface structure and properties are combined with field observational data and experimental pedogenesis in a joint fashion, testing of hypothesis can much better be directed towards generalizable theories on the mechanistic linkage of structure and function in soils and their evolution during pedogenesis. With this symposium we aim to discuss and debate the recent achievements, current obstacles, and future research directions to contribute to a synoptic understanding of the relationship between soil architecture and functions across scales. We specifically invite contribution from the different fields of soil research employing one or, in a joint fashion, more than one approach of the variety of experimental, observational, instrumental and computational methods.

Soil organic matter (SOM) plays a vital role not only in soil fertility and quality (by providing a number of physical, chemical, and biological benefits), but also in carbon cycling. SOM contains a vast range of diverse organic structures, and also a living component (microorganisms) with various residence times that define the central role SOM plays in the soil. The decline of SOM represents one of the most serious threats facing many arable lands of the world. One of the efficient approaches to increase SOM content and decrease land degradation is the application of organic amendments, such as crop residues and animal manures. Nowadays, organic amendments originate from many kinds of organic wastes, which are being increasingly produced mainly by farms, agro-food industries, municipalities, and energy plants. Besides serving as a source of organic matter and plant nutrients, these materials may contribute to reduce soil contamination, erosion, and desertification, as well as mitigate climate change. At the same time, a safe and useful application of organic amendments requires an in-depth scientific knowledge of their nature and impacts on the SOM pools and factions, soil-plant system, as well as on the surrounding environment.
This session will combine the current research and recent advances on the use of organic amendments in modern agriculture as well as for the restoration of degraded soils. Field and laboratory studies focused on the effects of management practices, climate change, environmental conditions, soil properties are highly welcome.

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.

Soil structure and its stability determine soil physical functions and chemical properties such as water retention, hydraulic conductivity, susceptibility to erosion, and redox potentials. These soil physical and chemical characteristics are fundamental for biological processes, among them root penetration and organic matter and nutrient dynamics. The soil pore network forms the habitat for soil biota, which in turn actively reshape it according to their needs. The soil biota, root growth, land management practices like tillage and abiotic drivers (e.g. wetting/drying cycles) lead to a constant evolution of the arrangement of pores, minerals and organic matter. With this, also the soil functions and properties are perpetually changing. The importance of the interaction between soil structure (and thus soil functions) on one side and soil biology, climate and soil management on the other, is highlighted by recent research outcomes, which are based on advanced imaging techniques, novel experimental setups and modelling approaches. Still, present studies have barely scratched the surface of what there is to discover.
In this session, we are inviting contributions on the formation and alteration of soil structure and its associated soil functions over time. Special focuses are on feedbacks between soil structure dynamics and soil biology as well as the impact of mechanical stress exerted by heavy vehicles deployed under land management operations. Further, we encourage submissions that are exploring new modelling concepts, integrating complementary measurement techniques or aim at bridging different scales.

The soil is a key system of the biosphere that supports the existence and development of human civilization. However, the growing anthropic activities are accompanied by an expansion of soil pollution. From a geochemical point of view, anthropic activities lead to the emergence of a new state of the biosphere - the noosphere, when anthropogenic chemical elements and their compounds are added to natural soil. This determines the current spatial heterogeneity of the chemical composition of the soil and vegetation cover. Such an alteration to soil composition/properties can cause negative biological impacts on both native and introduced species in local biocenosis, as well as the emergence of endemic diseases among plants animals, and humans. Human diseases can be aggravated by the fact that Homo sapiens evolving as a species under certain environmental/geochemical conditions inherited a corresponding need for certain dietary elements to maintain homeostatic regulation. As a result, people, like other organisms, need to ingest elements in the correct amounts, otherwise, they suffer from a deficiency or excess of these elements. A negative reaction may occur when the species’ natural metabolism fails to compensate for this imbalance in the life cycle. Therefore, complex studies on the identification, spatial distribution, migration, and concentration of the contaminants in soils, plants, and surface and groundwater in urban, mining, agricultural/forest, and natural areas, as well as its biological effects, is an essential issue and important task for 1)identification of zones of different natural and man-made ecological risks; 2)understanding contaminants’ pathways and impact, and 3)mitigation or elimination of negative biological effects, including the spread of non-communicable endemic diseases.
At this session, participants are invited to present their new data on soil pollution, as well as to show ideas and approaches to the solution of the problem of soil reclamation, to show results that contribute to modern knowledge on the ecological and geochemical assessment of various regions of the world exposed to anthropic geochemical impact, including industrial pollution, transport, mining and use of fertilizers and biocides. We also welcome presentations devoted to methodological problems on soil pollution assessment, the creation of ecological and geochemical databases, and compiling risk maps. We hope that live discussion will contribute to each study.