Homo sapiens as product of the natural evolution of the biosphere , was created as a species in the geochemical conditions of the virgin biosphere. After successful colonization of the adverse environmental conditions around the whole world, he started its transformation first by land cultivation, urbanization and now by creation a new habitat exclusively for man. All these have led to a significant geochemical transformation of the virgin biosphere. Nowadays, a growing variety of anthropogenic sources of pollution requires, not only a constant monitoring of the chemical state of soil, water, air and food products, but also the development of spatially differentiated approaches to assessing the health risk by evaluation of diseases’ provocation. To solve this problem, it is necessary to develop effective approaches towards interpretation of spatially related geochemical and medical information. In this way we propose to discuss: 1) the global trends of health transformation in geochemical environment of actual noosphere; 2) different approaches to assess the risk of diseases of geochemical nature in different countries; 3) criteria for determining pollution level depending on geochemical constrains and health effects; 4) the problem of mapping of risk zones, related to negative medical effects due to both excess and deficiency of certain chemical elements or compounds.

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. To support the goals of the various Open Science initiatives, this session looks at what is possible and what is applied in Earth Science.

We want to ask and find answers to the following questions:
Which approaches can be used in Earth Sciences?
What are the biggest challenges in bridging between scientific disciplines and how to overcome them?
What kind of participatory citizen scientist involvement 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?

Land degradation is a human-induced process deteriorating ecosystem functioning and services including soil fertility or biological productivity, and is accompanied by a loss of biodiversity. It causes on-site and off-site damages like change or removal of vegetation cover and soil erosion on one hand as well as flooding and siltation of receiving streams one the other hand. Thus, land degradation poses a threat to a number of sustainable development goals including foremost sustainable life on land and under water, the provision of clean water and eventually the eradication of poverty and hunger on Earth.
Often, land cover change is a valid indicator of land degradation providing the opportunity to take advantage of the increasing geometrically and temporally high-resolution remote sensing capabilities to identify and monitor land degradation. However, especially in semi-arid regions like savanna environments, globally driven inter-annual and decadal climate variations cause as well profound land cover dynamics which might be mistaken for land degradation.
Assessing and combating land degradation has already a long scientific, socio-economic and political history. Based on this, the aim of this session is to explore the wide range of methodological approaches to assess land degradation, its dynamics over all spatial and temporal scales as well as the implications for society and the interaction with the different spheres of the Earth including the anthroposphere, atmosphere, biosphere, hydrosphere or the pedosphere. Contributions to this session can be based on field work, remote sensing approaches or modelling exercises, they can also focus on specific physical and socio-economic aspects of land degradation like land management, land cover change or soil erosion or discuss land degradation in a broader societal context.

In this subdivision meeting, we want to give an overview on the last years' work in SSS3 and discuss and plan work for the upcoming year (SSS3 committee organization, session structure and planning, journal special issues etc.). We invite the participants of the SSS3 scientific sessions, and everybody interested in "Soils as records in time and space", to join our meeting!

Meet editors of internationally renowned journals in biogeosciences and soil system science 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 all 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. BG, SSS, NH and GM) 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.

Soil is one of the most significant components of the biosphere, and is essential to achieve the Sustainable Development Goals for 2030; to secure global environments, societies, and economies, for current and future generations. Over previous decades, the importance of the soil and its conservation has been increasingly recognised. However, growing population and associated demands for food, raw materials and physical space, have led to increasing soil threats and degradation. Although identified worldwide, these problems are particularly relevant in the Mediterranean region, where overall erosion rates are faster and soil organic matter is lower than in most of Europe. Additional soil threats, including soil compaction, sealing, contamination, decline in biodiversity and salinization, are also of relevant concern. Mediterranean areas also experience rural depopulation and abandonment, resulting in soil degradation favoured by problems such as wildfires and landslides. On the other hand, urbanization, particularly in the coastal zones, further increases pressure on soils. Furthermore, Mediterranean soils are more vulnerable to the adverse impacts of global warming, and are significantly susceptible to desertification. These threats are undermining the long-term capacity of soils to produce ecosystem services, and thus, enhancing soil resilience is a critical aspect to protect this non-renewable resource.
This session aims to discuss the state-of-the art of soil threats in the Mediterranean region, and the strategies used to mitigate soil degradation and enhance soil resilience in agriculture, forest, rangelands and urban areas. Specific aims include:
•Exchange knowledge on monitoring and data acquisition approaches, including laboratory and field-based measurements, remote sensing and modelling, to characterize the current status of soil degradation;
•Assess the main drivers of soil degradation and their environmental, social and economic impacts;
•Explore current and innovative technological and nature-based solutions to mitigate soil threats, restore degraded land and enhance soil resilience against global changes (e.g. land-use and climate);
•Discuss appropriate soil management practices to improve water and food security;
•Debate the role of Mediterranean soils on climate change adaptation and mitigation;
•Discuss governance and policy aspects relevant to soil protection and restoration in the Mediterranean.

Soil erosion is a major global soil degradation threat to land, freshwater and oceans. Scientific understanding of all erosional physical processes controlling soil detachment, transportation, and deposition is vital when developing methods and conservation alternatives to minimize the impacts associated with soil degradation.

This session will discuss the State-of-the-Art of the latest soil erosion measurements, monitoring and modelling techniques in agriculture, forest and rangelands. Our main objective is to scientifically discuss soil erosion but also to explore/present solutions that may help farmers and policy makers; supporting the ongoing activities aiming at achieving the SDG Target 15.3 land degradation neutral world by 2030 and the upcoming UN Decade on Ecosystem Restoration (2021-2030). This session will also discuss recent studies supporting improved understanding of gully and rill erosional physical processes, their impact locally, their off-site effects on sedimentation, and subsequent development of mitigation strategies.

It is essential for human well-being to restore degraded ecosystems and manage soil and water resources for sustainable development. In the past decades, connectivity has become important in the study of hydrological and geomorphic processes. The understanding of water and sediment connectivity can be applied to watershed management. The protection of habitats and species, the improvement of flood resistance and resilience, and the ecosystems maintenance are essential. In general, the target of watershed management is to maintain appropriate connectivity or disconnectivity in different ecological niches (hydrology, ecology, geomorphology), especially when external factors influence watershed processes and characteristics. Considering the high complexity of hydro-geomorphic systems, and the various processes that could affect the efficiency of water and sediment flowing through a watershed, studying the hydrological and sediment connectivity is essential. Also, analyzing changes in connectivity over time helps to understand the effects of natural and man-made disturbances on water-sediment flux and related processes. In this session, we welcome studies focused on connectivity at multiple spatio-temporal scales. Any contributions to the understanding of connectivity based on field monitoring, laboratory works, development and application of geomorphometric indices and models are welcomed. Our session emphasizes the value of connectivity in properly addressing sediment and water-related issues, and aims at providing important information on when, where and how to managers in order to control hydrological and geomorphic processes and ultimately achieve sustainable management.

Soils develop under the influence of various environmental factors that produce specific soil features, and thus keep a memory of nowadays and past environments. They also are valuable archives of past human activity, which has increasingly shaped environments and affected soil formation over the Holocene period.
Palaeosols, developed under the influence of past environmental conditions, are considerably valuable archives of past environments.They can be studied to reconstruct the environmental factors that were present during the time of their formation, and to disentangle the relative influences of different, local to regional, environmental background conditions on soil formation. Also peatlands have become increasingly recognized as a useful archive of palaeoenvironmental and palaeoclimatic archives. They offer a wide range of proxies (physical, geochemical and biological). Their global occurrence and high accumulation rates allow developing the past environmental change history of sub-decadal to millennial scales.
Human land occupation and cultivation often result in characteristic modifications of the surface, sediments and soils. Anthropogenically-affected soils keep a record of past human settlement cycles and land use and have enormous potential for geoarchaeological studies. Furthermore, their properties often clearly differ from those of the surrounding soils and thus also affect current ecosystems.
This session gathers contributions from all aspects of research dealing with soils as records of past environmental conditions, climate change and anthropogenic impacts; and with the geoarchaeological and ecological significance of anthropogenically-affected soils. A specific focus is on studies trying to provide more evidence for better understanding of the global definition of the Anthropocene and to distinguish the natural and human induced changes.

Documenting the diversity of human responses and adaptations to climate, landscapes, ecosystems, natural disasters and the changing natural resources availability in different regions of our planet, cross-disciplinary studies in Geoarchaeology provide valuable opportunities to learn from the past. Furthermore, human activity became a major player of global climatic and environmental change in the course of the late Quaternary, during the Anthropocene. Consequently, we must better understand the archaeological records and landscapes in context of human culture and the hydroclimate-environment nexus at different spatial and temporal scales. This session seeks related interdisciplinary papers and specific geoarchaeological case-studies that deploy various approaches and tools to address the reconstruction of former human-environmental interactions from the Palaeolithic period through the modern. Topics related to records of the Anthropocene from Earth and archaeological science perspectives are welcome. Furthermore, contributions may include (but are not limited to) insights about how people have coped with environmental disasters or abrupt changes in the past; defining sustainability thresholds for farming or resource exploitation; distinguishing the baseline natural and human contributions to environmental changes. Ultimately, we would like to understand how strategies of human resilience and innovation can inform our modern strategies for addressing the challenges of the emerging Anthropocene, a time frame dominated by human modulation of surface geomorphological processes and hydroclimate.

Arid to sub-humid regions contribute > 40 % to the global land surface and are home of more than 40 % of the world’s population. During prehistoric times many important cultures had developed in these regions. Due to the high sensitivity of dryland areas even to small-scale environmental changes and anthropogenic activities, ongoing geomorphological processes but also the Late Quaternary palaeoenvironmental evolution as recorded in sediment archives are becoming increasingly relevant for geomorphological, palaeoenvironmental and geoarchaeological research. Dryland research is also boosted by methodological advances, and especially by emerging linkages with other climatic and geomorphic systems that allow using dryland areas as indicator-regions of global environmental change.
This session aims to pool contributions from the broad field of earth sciences that deal with geomorphological processes and different types of sediment archives in dryland areas (dunes, loess, slope deposits, fluvial sediments, alluvial fans, lake and playa sediments, desert pavements, soils, paleosols etc.) at different spatial and temporal scales. Besides case studies from individual regions and archives, methodical and conceptual contributions, e.g. dealing with the special role of eolian, fluvial, gravitational and biological processes in dryland environments, their preservation over time in the sedimentary records, and emerging opportunities and limitations to resolve past and current dynamics, are especially welcome in this session.

Soil is a highly heterogeneous environment, both regarding space and time. From the spatial point of view, soil comprises a myriad of microhabitats that host an unparalleled biodiversity, from micro- to macrobiota. Several physical and chemical parameters define the soil microhabitat: the geometry of the pore space, its connectivity, the water micro-distribution and the nature, distribution and association of organic compounds within the soil mineral matrix (organo-mineral associations, soil aggregates). Variations in these parameters result in micro-gradients of oxygen, moisture, nutrients and organic compounds, acting as ecological filters for soil biota, usually promoting the co-existence of contrasting ecological strategies, with consequences for soil functioning. From a dynamic point of view, micro-scale heterogeneity is related to patterns of activity in soil, notably at the microbial level. Areas with high activity and fast process rates are defined as microbial hotspots (e.g rhizosphere, detritusphere, biopores, hyphasphere, aggregate surfaces, etc.). These hotspots show accelerated turnover of soil organic matter and other microbial functions (e.g. nutrient mobilization, litter decomposition, respiration, organic matter stabilization, greenhouse gas emission, acidification, etc.). The intensity of microbial and SOM turnover as well as nutrient cycling in such hotspots is at least one order of magnitude higher than in the bulk soil, and this can further affect the activity of other soil biota. In addition, microhabitats and soil hotspots are highly variable in time, being constantly re-modelled by numerous factors such as the alternation of wet and dry cycles, the activity of soil biota, especially plant roots and ecosystem engineers, and the input of fresh organic matter.
In this session we gather contributions on: (i) deciphering the main drivers of the formation and spatiotemporal variability of soil microhabitats (ii) quantifying the role of the soil microhabitat in determining soil ecology, and (iii) studies assessing the variability in soil activity within the soil matrix, notably at soil microbial hotspots. In particular, we tackle various aspects of microbial activity, interactions, community composition and distribution in hotspots, and factors influencing (micro)biological nutrient (re)cycling, including biotic and abiotic controls. The session presents a combination of field, experimental and modeling approaches.

The rhizosphere is regarded as the soil compartment with the highest level of nutrient flux through a multitude of interactions between plants, soil, and (micro)biota. Roots and associated (micro)organisms interact with heterogeneous soil environments that provide habitats for biota on various scales. High metabolic activity and nutrient cycling can be observed from single root tips to whole root systems which makes the rhizosphere of central importance for ecosystem functioning.
The main knowledge-gaps in rhizosphere research are related to the difficulty in mechanistically linking the physical, chemical and biological processes, taking place at different scales (nm to cm) in the rhizosphere and to the challenge of upscaling these processes to the scale of the root system and the soil profile. The key for overcoming these knowledge gaps is to understand rates of matter flux, and to link the spatial arrangement of the different interconnected components of the rhizosphere with their temporal dynamics. This requires concerted efforts to combine methods from different disciplines like plant genomics, imaging, soil physics, chemistry and microbiology.
We welcome experimental and modelling studies on rhizosphere functioning that aim at revealing spatial gradients of e.g. functional biodiversity of microorganisms, uptake and release patterns by roots, soil structure modification by root growth (and vice versa) as well as feedbacks between those processes in order to improve our mechanistic understanding of emerging properties like water acquisition, nutrient cycling, plant health, soil structure development and feedbacks among them.

Terrestrial ecosystems are being exposed to warming and to more frequent and intense drought and rainfall events as a result of climate change. Such changes can have strong implications for biogeochemical cycling and the functioning of soils. Understanding the mechanisms that control the responses to environmental stress is critical for improving predictions on the resistance and resilience of terrestrial ecosystems on a changing world.

The aim of this session is to bridge the knowledge of different disciplines to elucidate the processes and feedbacks underpinning the biogeochemical response to climate change, with emphasis on warming, drought, and drying-rewetting events. This session will give a broad overview of empirical and modelling studies across different scales, considering how climate change affects terrestrial biogeochemistry and the interactions between soil microorganisms, plants and fauna. We will focus on the resilience and the associated recovery dynamics of soil biota to environmental disturbances, as well as on their resistance or adaptation mechanisms to climate change. We will bring together researchers from different environments and create a discussion platform to review the current state-of-the-art, identify knowledge gaps, share ideas, and tackle new challenges in the field.

Part 1:
The fungal prime habitat is soil, and fungi are a key organism group for shaping the soil environment and influencing its functions. Their polarized, network forming growth, their diverse ecological roles such as mutualistic interactions with plants, decomposition of organic residues, their importance as pathogens/predators of various organisms, their role in soil structure buildup and their unique suites of metabolic compounds make them important players for many soil ecosystem functions.
We welcome contributions to this session that study fungal influences on soil functions such as biogeochemical cycling, decomposition and carbon storage, sustainable soil fertility, heavy metal and organic pollutant remediation, soil physics including aggregation, biodiversity relationships and trophic interactions. Contributions may involve both biotrophic (including the mycorrhizal) and/or saprotrophic fungi.

Part 2:
Soil biota provides services that are beneficial to the productivity and sustainability of land use systems. This session aims to discuss how land use systems affect soil biodiversity and how soil biodiversity (i.e. the performance of functional groups) feeds back to soil functions and ecosystem services. Knowledge is mounting that a sustainable intensification of land use needs to include the conservation of processes and functions run by soil biota that are essential for self-preservation considering services provided by soil biota including soil biodiversity. The joined European agricultural policy including soil and biodiversity conservation is asking for surveys throughout Europe. The strong progress in developing methods for biodiversity determination in soil and the quantification of biota specific impacts should be mirrored by the contributions. Moreover, transversal interactions with socio-economical sciences should lead to the development of tools to assess soil management as a socio-ecological issue.
This session will focus on the role of soil biology in delivering soil functions in systems formed by a human, e.g. agricultural, forests or restored sites and the synergies and trade-offs that occur within the bundle of soil functions, crossing several spatial and temporal scales. Additionally we welcome contributions aiming at promotion of soil managing practices that aim to optimize the multi-functionality of soils.

Ecosystem responses to climate change depend on both long-term and dynamic feedbacks occurring between soils, plants and microbial communities. Soil resources and microbial nutrient mineralization mediate vegetation growth. In turn, plants control soil properties through the production of organic residues which are decomposed in the soil, the supply of photosynthates to the rhizosphere, as well as the association with belowground communities. The interactive effects of these responses in the context of changing environmental conditions have a key influence on soil biogeochemistry and the belowground storage of carbon. In this session we invite contributions from manipulative field experiments, observations in natural-climate gradients, and modelling studies that explore the impact of climate change on plant-growth dynamics, microbial diversity and metabolism, as well as soil biogeochemical cycling. Submissions that adopt novel approaches (e.g. molecular, isotopic) or synthesize large-scale outputs focusing on plant-soil-microbe feedbacks to warmer temperatures or water limitation are also 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 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.

The storage, cycling and availability of Nitrogen (N), Carbon (C) and Phosphorus (P) in soils are widely researched topics; however, less investigation has been carried out regarding the coupling and interaction of the C-N-P cycles. This is especially relevant as the quantity and quality of these three elements and their proportions and interactions control fundamental soil functions such as soil fertility and microbial activity, which have profound impacts on key ecosystem services such as primary productivity, carbon capture or biodiversity.
Beside this, there is an urgent need to implement sustainable methodologies, which help to preserve soil quality and mitigate soil degradation. Under these assumptions, traditional and novel soil organic matter amendments will help us to maintain both agricultural yields as well as soil preservation. Increase of organic matter level in soil is not only a question of soil fertility but also a necessity of soil health maintenance and fighting against desertification.
In this session, we call for submissions on a wide range of topics covering C, N, and P cycles in soils, with a special focus on studies assessing their interactions, as well as the current research and latest advances focused on maintaining soil organic matter quantity and quality and therefore preserving soil functionality.
Our aim is to cover also a wide range of spatial scales, from microbial stoichiometry to ecosystem functioning, as well as a range of methodologies, from the microscale process understanding at laboratory scale up to field-based and modelling approaches. Studies in all types of soil and ecosystems, from natural forest to agricultural or urban soils, are welcome.

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. Special attention will be given to the soil chemical, physical, biological and biochemical aspects, including tracing the dynamics of SOM pools and fractions by using 13C/14C/15N/33P/18O isotopes. 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.

Wildfires induce physical and chemical alterations on soil properties, affecting both the quantity and composition of soil organic matter (SOM), and transforming biomass and SOM into pyrogenic carbon (PyC), also known as black carbon. PyC can derive from natural (e.g., wildfire charcoal), as well as anthropogenic sources (e.g., biochar) and it is recognized as important carbon sink in terrestrial and aquatic systems.

Wildfires and PyC can influence physical-, chemical-, and microbial soil functions by: changing composition and properties of native SOM which can modify soil physical properties (e.g. texture, structure, and moisture), changing redox- and pH conditions, and forming aggregates by mineral surface interaction of PyC micro- and nanoparticles. These changes can impact nutrient cycling and plant productivity, pollutant mobility, the soil microbiome, and edaphic fauna. These processes are of high importance for soil biochemistry, functioning, and carbon cycling, and to assess the environmental impact of wildfires for generating predictive tools that can be useful for post-fire restoration actions. To better understand the effects of Wildfires and PyC on soil, a wider knowledge of the abovementioned interlinked processes is urgently needed.

This session aims to bring together monodisciplinary as well interdisciplinary research on wildfire- and PyC-soil biochemistry, and carbon cycling, including studies on the alterations, impacts and cause-effect relationships induced by fire on SOM, as well as on describing recent advances on analytical techniques in the field. It welcomes submissions from lab- to field scale experiments as well as modelling, or meta-analytical approaches. Early career researchers and underrepresented groups in the field are strongly encouraged to apply.

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 nitrogen in terrestrial and aquatic ecosystems, b) and 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. 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. Furthermore, the interactions of nitrogen with other elemental cycles (e.g. phosphorus, carbon) and the impacts of these interactive feedbacks for soil health, biodiversity and water and air quality will be explored in this session. Latest developments in methodological innovations and observational and experimental approaches for unraveling the complexities of nitrogen transformations and transport will also be of interest.

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.

Despite the tight coupling between carbon (C) and nitrogen (N) cycling in terrestrial ecosystems, these two key elemental cycles are often studied separately, by different research groups using different methods and at different study sites. The aim of this session is to bring together scientists representing both fields of biogeochemistry in order to advance our understanding of the interactions between C and N cycling. C and N dynamics are altered in a changing climate through soil warming, changes in root exudates and litter input, changes in local hydrology, and disturbances including permafrost thaw and wildfires. While enhanced N availability may promote the C sink capacity of vegetation, complex interactions between climate, topography, soils, vegetation, and the microbial world will ultimately control the net ecosystem C and N balance in current and future conditions.
In this session, we welcome contributions that integrate both C and N dynamics across a variety of spatial scales, methods, and terrestrial ecosystem types that aim to address the challenges outlined above. Experimental and observational contributions focusing on ecosystem functions and compartments where C and N coupling occurs are encouraged, such as studies on plant-microbe interactions and priming, microbial processes coupling C and N cycles, and lateral transport of C and N to aquatic systems. We also welcome contributions describing new field and remote sensing methods and local and global models.

Physical (e.g. flow and transport), chemical (e.g. red-ox reactions) and biological (e.g. bio-mineralization) processes play a critical role in controlling reactive transport of contaminants in soils, the vadose zone, and deeper subsurface permeable media, for example during (bio)remediation operations. The characterization and modeling at different scales of such coupled processes in subsurface environments has motivated the development of novel experimental approaches, from laboratory to field, that are capable of quantifying the physical, chemical and biological properties of heterogeneous structures and of the related physical processes at different scales. Detailed experimental investigation and evidence of complex subsurface processes allow testing and validating new measurement techniques, and provide datasets with sufficient resolution and/or high spatial coverage to make the validation of coupled processes theories and numerical models possible.

The session will provide the opportunity for a multidisciplinary discussion based on recent advances in the experimental characterization and modeling of single and multiphase flows (including flows of non-Newtonian fluids), as well as conservative and reactive solute transport and bacterial activity, in porous and fractured media. Examples of such coupled subsurface processes include the dynamics of single and multiphase flows, NAPL dissolution and transport, mixing and mixing-controlled reactions, heat transfer, contaminant (bio)degradation, precipitation/dissolution reactions, bacterial dynamics and biofilm growth. Experiments featuring high resolution measurements with novel sensors, analytical, and imaging techniques, as well as novel modeling and upscaling techniques, will be addressed prominently.

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 invite contributions on soil structure, its formation and alteration and its associated soil functions. Special focuses are on feedbacks between soil physical or chemical processes and soil biology as well as the impact of mechanical stress exerted by heavy vehicles deployed under land management operations, which are linked with each other through a dynamic soil structure. Further, we encourage submissions that integrate complementary measurement techniques, explore new modelling concepts or aim at bridging different scales.

This session deals with the use of geophysical methods for the characterisation of subsurface properties, states, and processes in contexts such as hydrology, agriculture, contaminant transport, etc. Geophysical methods potentially provide subsurface data with an unprecedented high spatial and temporal resolution in a non-invasive manner. However, the interpretation of these measurements is far from straightforward in many contexts and various challenges remain. Among these, the need for improved quantitative use of geophysical measurements in model conceptualisation and parameterisation, and the need to move quantitative hydrogeophysical investigations beyond the laboratory and field scale towards the catchment scale. Therefore, we welcome submissions addressing advances in the acquisition, processing, analysis and interpretation of data obtained from geophysical and other minimally invasive methods applied to a (contaminant) hydrological context. In particular, we encourage contributions on innovations in experimental and numerical methods in support of model-data fusion, including new concepts for coupled and joint inversion, and improving our petrophysical understanding on the link between hydrological and geophysical properties.

The management of both soil and water resources is currently a primary socio-economic concern. The worrying increase in the pressure exerted on soils, surface, and groundwater, linked to climate change and intensive soil-management practices. In this context, knowledge of water and thermal transfer phenomena in the surface layers of soils, in interaction with aquifers on the one hand, and with the atmosphere on the other, plays an essential role. The modeling of water transfer in the soil across spatio-temporal scales with parameterizing soil characteristics and/or flows is crucial and at stake. The hydrodynamic characteristics of the soil must consider both soils textural and structural indicators
Infiltration is an essential component of the hydrological cycle. Estimating soil infiltrability is a key task for hydrologic, agronomic, ecological, and environmental studies. Despite the massive efforts and number of methods, determining soil hydraulic properties from infiltration experiments is hampered by the effects of spatio-temporal variability across scales. High-resolution measurements, both over space and time, are crucial to describe and analyze soil hydraulic properties adequately.
The session focuses on the principles, capabilities, and applications of both infiltration techniques and models:
- Field infiltration techniques from a wide variety of devices in combination with complementary measures and methods (i.e., TDR probes, GPR, ERT, etc.);
- New or revisited numerical and analytical models to account for multiple-porosity and multiple-permeability, hydrophobicity, clogging, shrinking-swelling, or biofilm development, as for many other factors that are considered in the soil-water flow models;
- Estimation of soil hydraulic parameters from infiltration experiments, e.g., the saturated-unsaturated hydraulic conductivity and sorptivity;
- The use of pedotransfer functions based on limited available in-situ data to estimate the parameters describing the hydro-physical and thermal soil characteristics;
- The impact of the quality of the description of soil properties on modeling.
We welcome contributions from simulated and real data investigations in the laboratory or field, successful and failed case studies, and the presentation of new and promising modeling approaches, scenarios, and techniques.

Preferential and non-uniform flows are induced by biotic (e.g., earthworms and roots) and abiotic factors and processes (e.g., wet-dry and freeze-thaw cycles, lithology, and structure) as well as anthropogenic activities (e.g., tillage and cultivation methods in agricultural land, human-made landforms from waste rock dumping and disposal strategies in mining). The understanding of preferential flow is of premium importance in relation to soil hydrology, as it can move a considerable amount of water and solutes in porous media. Preferential flows can occur spatially from the pore scale to entire catchments, across large regions. Temporally, the preferential processes can change during hydrological events, from within hours to seasonal events, and across inter-annual variations of years.
This session welcomes studies on experimental and theoretical challenges to identify, quantify, and model the key physical factors and processes that are responsible for preferential flows in porous media across scales (from pore scale to catchment scale). Contributions are welcome to reflect on experimental studies, novel approaches, and advances in solutions to:
• Understand the geometry and connectivity, formation and dynamics of fissures, fractures, and macropores and their effect on preferential flow;
• Understand the effect of physical processes and geochemical processes on the dynamics of macropores and fracture networks;
• Develop and refine models for quantifying preferential flow, from pore scale to pedon scale and entire catchments and landscapes;
• Unpacking the pore structure of soil using new methods and approaches, including the use of non-Newtonian fluids, for improved characterization of heterogeneous soils and the advancement of flow and transport modeling.

Vadose zone hydrology studies the physical processes in the unsaturated zone. Modeling and observation of soil and vadose zone processes aims at characterizing soil properties and quantifying terrestrial water storage dynamics. The states of soil, air and water affect biogeochemical processes, vegetation water availability, nutrient and pollutant transport at local scale, catchment response functions and rainfall-runoff processes at intermediate scale, land-atmosphere interaction and land-climate feedbacks at the continental scale. Advanced measurement techniques, increased availability of high-frequency data, and the need for terrestrial system understanding challenges vadoze zone modeling concepts, budging model parameterizations from static to near dynamic. This session aims to bring together scientists advancing the current status in modelling soil and vadose zone processes from the pore to the catchment and continental scale. Contributions to this session address soil hydrological processes, characterization of soil properties and soil hydraulic properties, soil biogeochemical processes and their interactions with hydrology, transport of pollutants, and soil vegetation atmosphere modelling.

Land degradation affects more than 52 billion hectares of land around the world. This is caused to a large extent by anthropogenic activities such as land abandonment, mining activities, deforestation, and inadequate land use and management. Disturbance or insufficient rebuilding of the soil physicochemical and biological characteristics can modify the ecosystem functions and services. In the absence of appropriate restoration, soils and ecosystems would remain in a disturbed state or continue to decline. Therefore, restoration and rehabilitation of degraded soils is critical to create healthy and functional ecosystems that support essential functions and services.
In this session, we welcome contributions covering research conducted in this area of research describing experimental, observational, and theoretical studies. Topics of interest are (although not limited to) causes and impacts of land degradation and remedial actions and strategies for soil restoration and rehabilitation at local, regional or global scales.

The growing amount of data on chemical composition of soils all over the world shows constantly increasing anthropogenic activity accompanied by emissions of chemical elements and compounds in quantities exceeding natural background levels, which leads to contamination of basic foods of plant and animal origin. However, the diversity of pollution sources and their location in different climatic, physiographic and geochemical conditions require the development of differentiated approaches to assess and prevent the risk of adverse health and environment effects. The development of technologies for the rehabilitation of soil properties, including its fertility is also a challenge. The problem of soil monitoring and rehabilitation is becoming increasingly topical due to population expansion to abandoned mining areas as well as other polluted industrial areas. We invite researchers to share their ideas and results of studying soil contamination/rehabilitation at various spatial levels - from children's and sports grounds to large cities, abandoned and existing areas of mining, existing and former agricultural areas, etc.. Studies of the site-specific forms of occurrence, migration and accumulation of rare earth and potentially hazardous elements in soils, from different natural and anthropogenic transformed substrata are particularly welcome. We consider it especially important to evaluate the variation and spatial distribution of natural and man-made associations of macro- and microelements as a key to understanding the dynamics of the existence and sustainability of natural and anthropogenic substances and their spatial structures formed in soils that you need to know to provide safe operation of polluted land.

Soil pollution is a worldwide problem degrading soils with a direct impact on food security, human health and the environment. Unsustainable farming practices, industrial activities and mining, untreated urban waste have progressively contaminated soil, air and water. The spatial variability of contamination is a crucial problem when evaluations are required to address reclamation or phytoremediation on agricultural or industrial contaminated sites, because location, content, nature and form of potentially toxic elements (PTE) and/or chemical compounds are usually little-known. Proper investigation tools are necessary to identify the geography of soil contamination, as well as the variability (in space and depth) of soil chemical, physical and hydrological properties, due to their direct influence on soil capacity to filter and buffer contaminants, degrade and attenuate negative effects of PTE and chemical compounds. Soil remediation techniques using several wastes are effective for the recovery of soil properties and fertility whilst decreasing pollutants bioavailability, thus stimulating circular economy (recycling of organic and inorganic wastes), which is a key aim of the new Green Deal policy framework to stimulate lead markets for climate neutral and circular products, in the EU and beyond.
Under this perspective, this session has the aim to converge research studies presenting the most relevant advances on i) the use of ground-breaking technologies aimed to the knowledge of spatial variability of soil pollution and ii) application of soil remediation techniques in the framework of the circular economy.
Main topics addressed: use of sensors and field techniques for soil spatial variability and pollution assessment, mapping of soil organic and inorganic contaminants, contamination affecting soil ecosystem functions and services, precision remediation actions and technologies applied to contaminated sites towards circular economy, modelling of soil hydrological properties as media to forecast and prevent groundwater pollution, Spatial Decision Support Systems as policy tools for monitoring and managing soil pollution.

Sorbent materials have various environmental applications, i.e. water filtration, separation, and purification. Rapid progress in nanotechnology and a new focus on biomass-based instead of non-renewable starting materials have produced a wide range of novel engineered sorbents. The development and evaluation of novel sorbents requires a multidisciplihttps://meetingorganizer.copernicus.org/EGU2020/so1/35078nary approach encompassing environmental, nanotechnology, physical, analytical, and surface chemistry. The necessary evaluations encompass not only the efficiency of these materials to remove contaminants from surface waters and groundwater, industrial wastewater, polluted soils and sediments, etc., but also the potential side-effects of their environmental applications. Contributions examining the use of novel sorbents for environmental remediation are welcome. More specifically the contributions may be focused on:

• biosorbents: characterization; evaluation;
• biochars: process optimization; physically and chemically activated biochars;
• reactive sorbents: development; characterization; evaluation;
• nanotechnology based sorbents: development; characterization; evaluation;
• development of sorbents, reactive sorbents, or catalysts from geomaterials;
• sorbent-based in-situ remediation of contaminated soils, aquifers and sediments: experimental work; field studies;
• ecotoxicity of novel sorbents.

The soil-plant system, as a key part of the environment, can play a crucial role for achieving one of the goals of the European Green Deal, “A zero pollution ambition for a toxic-free environment”. Soils are the basis of terrestrial ecosystems and a crossroad of biogeochemical cycles at the lithosphere-hydrosphere-biosphere-atmosphere interface. However, soils are a limited and fragile resource. Soil health and quality is crucial for food quality production as well as to contribute to boost biodiversity. Soil pollution is, together with other threats (e.g. soil erosion, soil compaction, loss of organic matter), one of the most important concerns contributing for soil degradation and biodiversity loss. Human activities are the sources of soil pollution, such as, the mismanagement of industrial agriculture and mining activities, sewage and waste disposal, contributing to increase the concentration of potentially toxic substances (metals/metalloids, radionuclides and organic compound) in the ecosystems.
Remediation techniques are considered as cost-effective and environmentally friendly technologies for the in situ restoration of the health and productive capacity of soils, mitigating environmental impacts of impaired soils, and last but not least, the recovery of raw materials. Phytoremediation that consider the soil-plant system and particularly the rhizosphere area and soil biota, are effective approaches towards the recovery of polluted soils. These recovery techniques should be introduced and encouraged as they are more environmentally friendly, sustainable and affordable.
Bioremediation and biomining techniques involve the i) extraction of inorganic pollutants or economically valuable elements from soils or technogenic substrates , ii) stabilization of potentially toxic elements in the root zone of plants as well as iii) the microbial degradation of organic pollutants. Optimization and establishment of these technologies requires a sound understanding of soil-associated factors and plant-associated factors as well as root-soil-microbial interactions in the rhizosphere of plants controlling the mobility and availability of the target compounds in soils.

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 relation 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.

The present context of accelerated changes in both climate and land use imposes an unprecedent pressure on a number of vulnerable ecosystems including wetlands, forests and rangelands, in which vegetation closely interacts and coevolves with soils and landforms. Complex interactions between climate, soils and biotic factors are involved in the development of landform-soil-vegetation feedbacks and play an important role in making ecosystems resilient to disturbances. In addition, large shifts in the distribution of vegetation and soils are associated with losses of ecosystem services (including carbon capture), frequently involving thresholds of ecosystem stability and nonlinear responses to both human and climatic pressures. This session will focus on ecogeomorphological and ecohydrological aspects of landscapes (including their connectivity), conservation of soil resources, and the restoration of ecosystem services and functions. We welcome theoretical, modelling, and empirical studies addressing the distribution of vegetation and coevolving soils and landforms, and particularly, contributions with a wide appreciation of the soil erosion-vegetation relationships that rule the formation of landscape-level spatial organization. We also welcome studies describing the implications of these spatial patterns of soils and vegetation for the resilience and stability of ecosystems under the pressure of climate change and/or human disturbances.

As an integral part of terrestrial ecosystems, soils play a crucial role in the provision of numerous ecosystem services. Soil ecosystem services are vital components to all aspects of life and support the production of ecosystem goods and services, such as food and fiber production, water storage and climate and natural hazards regulation, among many others. The provision of soil ecosystem services relies on soil characteristics, processes and functions. Moreover, healthy and diverse soils ensure biodiversity among soil biota (soil biodiversity), which in turn guarantees the provision of soil ecosystem services. Incorrect land uses such as intense land management may critically reduce the ecosystem services provided by soils and result in land degradation through erosion, sealing or pollution processes. Sustainable land management and the conservation and restoration of degraded ecosystems is therefore key to maintain functional soils that can provide multiple ecosystem services. By 2030, the Agenda for Sustainable Development – the 17 ‘Sustainable Development Goals’ – are intended to be achieved. The role of soil science, and the work between soil scientists and other disciplines, will be paramount over the coming decade. In particular, healthy and sustainable soil management plans will need to ensure that soils continue to deliver services to ecosystems, societies, and economies. Global climate change and the burgeoning demands from a growing world population are set to place escalating pressures on soils, suggesting an urgent need to build resilience into soil management whilst also reversing current global trends of soil degradation.
In this session, we welcome contributions covering inter and transdisciplinary research through observational, theoretical and applied studies, on soil ecosystem services and soil function in the context of a changing global environment. Topics of interest are (although not limited to): 1) Impacts of soil degradation on soil function and ecosystem services, 2) Soil conservation and restoration actions for maintaining ecosystem services (including research, management, education and policy), 3) Linking soil ecosystem services and soil function in the context of the SDGs.

This session is supported by the project A09.3.3-LMT-K-712-01-0104 Lithuanian National Ecosystem Services Assessment and Mapping (LINESAM) is funded by the European Social Fund according to the activity “Improvement of researchers” qualification by implementing world-class R&D projects.

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

Silicon (Si) is crucial in numerous biochemical and geochemical processes. Earlier scientific literature on Si cycling focused on abiotic weathering processes, while in recent years, scientists have become more aware of the significant role of biotic controls. Silicon plays a key role in processes governing soil formation and soil-plant feedback interactions. Vegetation, soil organisms, including fauna, microorganisms and fungi, strongly affect Si dynamic in terrestrial ecosystems but the mechanisms are still poorly understood. In particular, Si has numerous beneficial effects on both plant structure, function as well as resilience to biotic and abiotic stresses motivating studies focusing on Si functional ecology and silica biomineralization. The global Si cycle is receiving increased attention because of its links with the carbon cycle as well as other major biogeochemical cycles and toxic elements. A better understanding of the terrestrial Si cycle is thus critical, especially as drastic and subtle changes in the terrestrial Si cycle are occurring worldwide in response to global change.
This session aims at compiling recent work focusing on biogeochemical Si cycling under global change, its functions in terrestrial ecosystems as well as its evolution in the recent past. This session bridges advances from soil sciences, ecology, plant physiology, agronomy, biogeochemistry (including isotopes studies) and palaeontology. We invite studies tackling biotic and abiotic interactions at different time and spatial scales affecting the Si cycle and its interactions with other biogeochemical cycles. We encourage interdisciplinary studies as well as contributions from both field and laboratory experiments encompassing biogeochemical processes, molecular mechanisms to improve our understanding of the role of Si in ecosystem processes. Meta-analyses and paleo-environmental studies using phytoliths are also welcome.

Tropical ecosystems are biomes of global significance due to their large biodiversity, carbon storage capacity, and their role in the hydrological cycle. Historic and recent human activities have, however, resulted in intensive transformation of the tropical ecosystems in the Amazon, Central America, Central Africa and in South East Asia impacting the cycling of nutrient, carbon, water, and energy. Understanding their current functioning at process up to biome level in its pristine and transformed state is elemental for predicting their 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 tropical ecosystems across spatial and temporal scales by means of remote and in-situ observational, modelling, and theoretical studies. Particularly welcome are presentations of novel, interdisciplinary approaches and techniques.

Soil is the largest carbon (C) reservoir in terrestrial ecosystems with twice the amount of atmospheric C and three times the amount in terrestrial vegetation. Carbon related ecosystem services include retention of water and nutrients, promoting soil fertility and productivity and soil resistance to erosion. In addition, changes in the soil C can have strong implications for greenhouse gas emissions from soil with implications in environmental health.

Drivers controlling C pools and its dynamics are multiple (e.g. land use/vegetation cover, climate, texture and bedrock, topography, soil microbial community, soil erosion rates, soil and other environment management practices, etc. ) and some of them are mutually interacting. Also, rate of net soil C loss can be high in some environments due to both climatic constrains or management. Thus, investigation of C dynamics should be addressed with regards to the climate change and climatic extreme events to provide a better understanding of carbon stabilization processes and thus support decision making in soil management and climate adaptation strategies.

The present session highlights the importance of soil C changes, and the interaction among the mechanisms affecting C concentration and stocks in soil. Discussion about the proxies to measure and model C stocks, with special emphasis to cropping systems and natural/semi-natural areas, is encouraged. These proxies should be approached at varying the availability of soil and environment information, including, e.g., soil texture, rainfall, temperature, bulk density, land use and land management, or proximal and remote sensing properties. Studies presented in this session can aim to a wealth of aims, including soil fertility, provision of ecosystem services, and their changes, and the implication for economy, policy, and decision making.

Types of contribution appreciated include, but are not limited to, definitive and intermediate results; project outcomes; proposal of methods or sampling and modelling strategies, and the assessment of their effectiveness; projection of previous results at the light of climate change and climatic extremes; literature surveys, reviews, and meta-analysis. These works will be evaluated at the light of the organisation of a special issue in an impacted journal

This session offers an opportunity to present studies or professional works regarding irrigated agriculture with disciplinary and multidisciplinary approaches copying with the challenges that the COVID19 scenario brings to the researches and society, such as:
• Resilience of irrigated areas at different spatial scales, mainly when water and soil are limiting factors.
• Estimation of crop transpiration/crop water requirement, even considering the possibility to apply controlled water deficit conditions.
• Coupling natural and human systems where ground and surface water and land are limiting resources for irrigation
• Safety in marginal water use in irrigated agriculture
• Traditional, novel, and transitional technologies for irrigation management, control and practical application at different spatial scales.
• Reducing the cost of technology monitoring soil and plant water status, and improving the quality of data acquired from the sensors, as well as on integrating the acquired data into easy-to-use Decision Support System.
• Potential of available remotely and proximal sensed data, mainly referring to those platforms and instruments acquiring frequently high-resolution data, to tackle current and future irrigation problems at different spatial scales.
• Improving the integration of climate change scenarios and weather forecast into agro-hydrological models and decision support systems to improve decisions in irrigation management and in safe surface water-groundwater interactions.
Posters and oral communications are available.

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 terroir effect 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 issue of climate change. In this sense, it is important to stress that in the last decade, the study of terroir has shifted from a largely descriptive regional science to a more applied, technical research field, including: sensors for mapping and monitoring environmental variables, remote sensing and drones for crop monitoring, forecast models, use of microelements and isotopes for wine traceability, metagenome approach to study the biogeochemical cycles of nutrients.
Moreover, public awareness for ecosystem functioning has led to more quantitative approaches in evidencing the relations between management and the ecosystem services of vineyard agroecosystems. Agroecology approaches in vineyard, like the use of cover crops, straw mulching, and organic amendments, are developing to improve biodiversity, organic matter, soil water and nutrient retention, preservation from soil erosion.
On those bases, the session will address the several aspects of viticultural terroirs:
1) quantifying and spatial modelling of terroir components that influence plant growth, fruit composition and quality, mostly examining climate-soil-water relationships; 2) terroir concept resilience to climate change; 3) wine traceability and zoning based on microelements and isotopes; 4) interaction between vineyard management practices and effects on soil and water quality as well as biodiversity and related ecosystem services.

Wildfires are a global phenomenon responsible for tremendous environmental, social and economic losses, which combined with land abandonment, absence of appropriate land management, and urban planning, are expected to exacerbate land degradation and deteriorate the ecosystem services.
But now, wildfires are becoming a persistent threat as shown by the fire risk increase as a consequence of a warmer and drier climate, demanding from the scientific community novel tools for integrated post-fire land management and impact mitigation. This research urges the attention of researchers, stakeholders and decision-makers all over the world since wildfire impacts on soils and ecosystems are severely affecting ecosystem services supply such as raw material and water provisioning, carbon storage, erosion and flood control, and habitat support, which are essential for human life on earth.
The aim of this session is to join researchers that study the effects of wildfires on ecosystems from wildfire prevention to post-fire mitigation. We warmly invite studies that approach by means of laboratory, field experiments, and/or numerical modeling, the following subjects:
i. prescribed and/or experimental fires;
ii. fire severity and burn severity;
iii. fire effects on vegetation, soils and water;
iv. post-fire hydrological and erosive response;
v. post-fire management and mitigation;
vi. , and socio-economic studies on post-fire land management.

Soils provide many essential functions which are indispensable for terrestrial ecosystems and the health of human societies. Beyond the production of biomass these functions are nutrient cycling and retention, filtering and buffering of water, storage of carbon and habitat for an overwhelming biodiversity.
In view of an increasing pressure on agricultural soils and the need for sustainable soil management all these functions need to be taken into account. They emerge from complex interactions between physical, chemical and biological processes in soil and are all affected by multiple societal demands. This need to be understood and disentangled to predict the impact of agricultural soil management on soil functions. The intention of this session is fourfold. We seek contributions which (i) broaden and advance our perspective on soil functions, (ii) enhance our current process understanding of how soil management practices impact one or more soil functions, (iii) show how to quantify soil functions based on suitable proxies or indicators and (iv) demonstrate how soils resist and recover from perturbations.

Natural disturbances in forests, including windthrow events, insect infestations, wildfires and droughts have intensified in severity, frequency, and extent over the last few decades, and ongoing climate change is predicted to further accelerate these trends. If disturbance regimes exceed ecosystem resilience thresholds, forests may change to a new permanent state (e.g. turnover of tree species composition) or may convert fully into non-forest ecosystems.

Forest management practices can influence both the resistance and resilience of a forest ecosystem to its disturbances, in terms of outcomes for biodiversity, nutrient cycling, and the biochemical and physical properties of landscapes. Promotion of mixed species forestry, for instance, can increase stand stability against windthrow, and might decrease forests’ vulnerability to insect attacks or drought. Retention of dead wood, on the other hand, is thought to enhance the recovery of forest structure and complexity, as well as above and below-ground diversity. Type, scale and intensity of disturbance events, along with pre- and post-disturbance management practices, may ultimately lead to changes in vegetation dynamics and plant-soil-atmosphere interactions.

In this session, we hope to stimulate scientific exchange among ecological research disciplines, broaden the view on how forest management shapes forest susceptibility to natural disturbances, and draw attention to how management can alleviate post-disturbance effects on ecosystem functioning. We aim to bring together research spanning from tree and soil processes at the microscale to landscape-level dynamics. We invite contributions investigating natural forest disturbances and pre- and post-disturbance management practices from a variety of perspectives, including:
• Vegetation dynamics;
• Micro-meteorology;
• Plant physiology;
• Soil sciences;
• Microbiology.

Contributions based on observational, experimental, and modeling studies as well as reviews and syntheses are welcome.

The interactions between plants and the environment play a prominent role in terrestrial fluxes and biochemical cycles, but we still lack a general understanding of how these interactions impact plant growth and plant access to soil resources particularly under deficient conditions. The main challenge arises from the complexity of both soil and plants. To address such a knowledge gap, an improved understanding and predictability of plant-related transfer processes are urgently needed.
Emerging experimental techniques such as non-invasive imaging technique and system modeling tools have deepened our insights into the functioning of water and solute transport processes in the soil-plant system. Quantitative approaches that integrate across disciplines and scales constitute stepping stones to foster our understanding of fundamental biophysical processes at the frontier of soil and plants.
This session targets researchers investigating plant-related resource transfer processes across different scales (from the rhizosphere to the global scale) and welcomes scientists from multiple disciplines ranging from soil to plant sciences. We are specifically inviting contributions of:
- Measuring and modeling of water and solute fluxes across soil-plant-atmosphere continuum at different scales.
- Novel experimental and modeling techniques assessing below-ground plant processes such as root growth, root water, and nutrient uptake, root exudation, microbial interactions, and soil aggregation
- Measuring and modeling of soil-plant hydraulics
- Bridging the knowledge gap between biologically and physically oriented research in soil and plant sciences
- Identification of plant strategies to better access and use resources from soil under abiotic stress
- Mechanistic understanding of drought impact on transpiration and photosynthesis and their predictions by earth system model

The proper management of water resources is a key aspect of soil conservation in arid and semiarid environments, where any irrigation activity is structurally and deeply related to the understanding of soil hydrological behaviour. In these areas, irrigation should be regarded to as a fundamental element of any agroecosystem and an effective defence against desertification. Its importance goes beyond the technological aspects, often being traditional irrigation a cultural heritage, which requires to be faced with an (at least) interdisciplinary approach which involves also humanities. On the other hand, improper practices may contribute to soil degradation. As an example irrigation may lead to soil salinization, with dramatic fallout on agricultural productivity, and overgrazing may lead soil to compaction, with negative effects on the soil capability of water buffering.

This session welcomes contributions ranging from the understanding of the soil hydrological behaviour and of the mass fluxes, through the soil, in arid and water—scarce environments and also under stress conditions (e.g. water shortage, compaction, salinization), to the interaction between soil hydrology and irrigation, and to the design of irrigation systems in arid districts and oases, including also the use of non—conventional waters (e.g. water harvesting). Particular attention will be given to the maintenance and improvement of traditional irrigation techniques as well as to precision irrigation techniques, also with local community involvement. Interdisciplinary contributions, which deal with different aspects and functions of the link between soil hydrology and irrigation techniques in arid environments, are encouraged.

This session is co-sponsored by the International Commission on Irrigation and Drainage (ICID).

A grand challenge facing society in the coming decades is to feed the growing human population in a sustainable and healthy manner. This challenge is central to many of the United Nations Sustainable Development goals (SDGs), including the zero hunger goal but also those for human health, water, terrestrial biodiversity and sustainable production and consumption.
This problem is made more complex by an increasingly globalised food system and its interactions with a changing climate. Agri-food system actors - including policy makers, corporations, farmers, and consumers - must meet this challenge while considering potentially conflicting priorities, such as environmental sustainability (e.g., minimising disturbance to ecosystems via greenhouse gas emissions and the use of water, land, fertilisers and other inputs), economic viability (e.g., revenues for food producers and guaranteed access for consumers), nutritional balance and quality (e.g., addressing overconsumption and undernourishment), and resilience to climate change.
This growing complexity of agri-food systems, which can involve global supply chains and difficult environmental and societal tradeoffs, needs to be better understood.
The type of product (e.g. plant or meat based, fresh or processed), as well as the location and method of production, can play an important role in improving the nutritional quality and environmental sustainability of global food production, to enable healthy and sustainable diets. Quantifying and assessing these multiple outcomes while accounting for the linkages, interconnections, and scales of local and global supply chains will be essential for informing decisions aimed at developing sustainable and resilient agri-food systems.
This session welcomes submissions that quantify and assess a range of outcomes from agri-food systems across multiple spatial and temporal scales, and the trade-offs or synergies between them. The session will include studies providing improved methods for quantifying multiple environmental, economic or social dimensions, studies that incorporate the role of food trade into solution-development, and studies that seek to achieve multiple sustainability goals together.

Food traceability is an important issue in food security and quality control.
The possibility of tracing the origin of food stuff is assuming an increasingly important role at the legislative level, as a tool that may allow to prove on product authenticity and to control adulteration.
Establish geochemical and isotopic analytical approaches to trace food play a key role to ensure food safety.

The importance of soil quality and its functions such as nutrient cycling, carbon sequestration, water quality and biodiversity for climate regulation and a sustainable agriculture is more and more recognized. As a limited resource, soil is permanently under pressure and also highly affected by climate change. It often remains unclear how environmental change as well as new management strategies influence the various soil functions and their interactions on the different scales.

Computational models can help to understand and predict effects of a changing environment on soil properties, functions and their relationship by describing soil processes and organism dynamics. However, combining different interrelated functions and processes of a complex system such as soil remain rather challenging especially when scale transfers are needed. Related to that, there is an ongoing debate in how far and to what level of detail biological processes and interactions need to be represented in modelling soil functions.
This is a formidable scientific challenge related to upscaling soil processes from detailed interactions at the pore scale to effective soil functions at the scale of soil profiles or even the landscape scale.

With this session, we want to address several open questions:

a. What biological processes do we need to consider for modelling the dynamics of soil functions?
What data or mechanistic knowledge is missing for modelling soil functions and biological processes?
What are the relevant metrics representing key soil functions and defining soil quality?

b. How much details are needed to adequately describe the system, while keeping models simple enough for understanding their dynamics on different scales?
How important is the incorporation of spatial heterogeneity?

c. What is the appropriate level of model complexity to advice on optimal agricultural management practices?
What can we gain from such models to optimize field experiments?

This session presents theoretical concepts, scaling approaches and mechanistic models for simulating soil properties, functions and biological processes; as well as experimental or field studies which may help to improve modelling approaches.

This session has been promoted by:
Sustainable Agroecosystems (AGRISOST, https://www.agrisost.org/en/)
International Soil Modeling Consortium (ISMC, https://soil-modeling.org/)

Spatial soil information is fundamental for environmental modelling and land use management. Spatial representation (maps) of separate soil attributes (both laterally and vertically) and of soil-landscape processes are needed at a scale appropriate for environmental management. The challenge is to develop explicit, quantitative, and spatially realistic models of the soil-landscape continuum to be used as input in environmental models, such as hydrological, climate or vegetation productivity (crop models) while addressing the uncertainty in the soil layers and its impact in the environmental modelling. Modern advances in soil sensing, geospatial technologies, and spatial statistics are enabling exciting opportunities to efficiently create soil maps that are more consistent, detailed, and accurate than previous maps while providing information about the related uncertainty. The production of high-quality soil maps is a key issue because it enables stakeholders (e.g. farmers, planners, other scientists) to understand the variation of soils at the landscape, field, and sub-field scales. The products of digital soil mapping should be integrated within other environmental models for assessing and mapping soil functions to support sustainable management. Examples of implementation and use of digital soil maps in different disciplines such as agricultural (e.g. crops, food production) and environmental (e.g. element cycles, water, climate) modelling are welcomed. All presentations related to the tools of digital soil mapping, the philosophy and strategies of digital soil mapping at different scales and for different purposes are also welcome.

Several targets of Sustainable Development Goals depend on the soil condition, as they impact ecosystems functioning and food, fibre and timber production. Soil condition regulates the climate, hydrological and nutrient cycle and provide resilience against floods and droughts. Addressing these global issues also requires reliable tools for global soil monitoring, such as Earth Observation (EO) products for mapping and monitoring soils, including their uncertainty. This contemporary research would greatly benefit from synergies between pedometrics and spectroscopy/remote sensing scientists. There is the need to create models linking soil properties with ancillary environmental variables, such as proximal and remote sensing data and that help quantifying uncertainty. These models will allow to understand the processes happening in the soil and in the landscape with space-time patterns, at different scales. In this session, we aim to bring together scientists working on research related to using the full range of pedometrics and soil sensing techniques available for mapping and monitoring soils. A preliminary view indicates some pillars as follows: a) the link between spectroscopy and wet soil laboratory analysis, seeking for the best strategy to evolve soil quality analysis; b) the link between proximal and remote sensing, with soil analysis; c) the link between proximal/remote sensing and pedometrics for extrapolating relationships established at point support to the spatial and temporal extent covered by proximal/remote sensing. We will aim to identify priorities for the future in what is an active area of collaborative research.

Land use, land-use change and forestry (LULUCF) sector is the only sector in National green-house gas (GHG) Inventory that accounts for carbon (C) removals, therefore it has been recognized as important for reaching the long-term climate mitigation objectives. Recently, an issue of uncertainty of the LULUCF sector estimates is strongly being emphasized and scientific community is facing a growing need to facilitate national reporting regarding C emissions/removals under LULUCF sector.
National level estimates often require long-term and comprehensive datasets at national scale, like national forest inventories (NFI), but these data are not always available. To overcome this gap, multi-source data integration, remote-sensing and modelling approaches are commonly used, but all these methods carry many issues.
This session invites contributions on national and subnational carbon budget estimates (past, present and future) in different land uses (forests, crops, grasslands, urban areas) using multiple data sources and different calculation methods. NFI-based, remote sensing and modelling studies on C stocks and/or fluxes in different ecosystem pools (live biomass, dead wood, litter or soil) are encouraged.
Aim is to provide extensive overview of different methodological approaches that can be used for national scale estimates and highlight main issues regarding data integration and model calibration and validation process.

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.

Geostatistical methods are commonly applied in the Water, Earth and Environmental sciences to quantify spatial variation, produce interpolated maps with quantified uncertainty and optimize spatial sampling designs. Space-time geostatistics explores the dynamic aspects of environmental processes and characterise the dynamic variation in terms of correlations. Geostatistics can also be combined with machine learning and mechanistic models to improve the modelling of real-world processes and patterns. Such methods are used to model soil properties, produce climate model outputs, simulate hydrological processes, and to better understand and predict uncertainties overall. Big data analysis and data fusion have become major topics of research due to technological advances and the abundance of new data sources from remote and proximal sensing as well as a multitude of environmental sensor networks. Methodological advances, such as hierarchical Bayesian modeling, machine learning, sparse Gaussian processes, local interaction models, as well as advances in geostatistical software modules in R and Python have enhanced the geostatistical toolbox.

This session aims to provide a forum where scientists from different disciplines can present and discuss innovative geostatistical methods targeting important problems in the Water, Earth and Environmental sciences. We also encourage contributions focusing on real-world applications of state-of-the-art geostatistical methods.

The topics of interest include:
1) Space-time geostatistics for hydrology, soil, climate system observations and modelling
2) Hybrid methods: Integration of geostatistics with optimization and machine learning approaches
3) Advanced parametric and non-parametric spatial estimation and prediction techniques
4) Big spatial data: analysis and visualization
5) Optimisation of spatial sampling frameworks and space-time monitoring designs
6) Algorithms and applications on Earth Observation Systems
7) Data Fusion, mining and information analysis
8) Geostatistical characterization of uncertainties and error propagation
9) Bayesian geostatistical analysis and hierarchical modelling
10) Functional data analysis approaches to geostatistics
11) Multiple point geostatistics

This session is co-sponsored by the International Association for Mathematical Geosciences (IAMG), https://www.iamg.org/

Environmental systems often span spatial and temporal scales covering different orders of magnitude. The session is oriented in collecting studies relevant to understand multiscale aspects of these systems and in proposing adequate multi-platform and inter-disciplinary surveillance networks monitoring tools systems. It is especially aimed to emphasize the interaction between environmental processes occurring at different scales. In particular, a special attention is devoted to the studies focused on the development of new techniques and integrated instrumentation for multiscale monitoring high natural risk areas, such as: volcanic, seismic, energy exploitation, slope instability, floods, coastal instability, climate changes and other environmental context.
We expect contributions derived from several disciplines, such as applied geophysics, geology, seismology, geodesy, geochemistry, remote and proximal sensing, volcanology, geotechnical, soil science, marine geology, oceanography, climatology and meteorology. In this context, the contributions in analytical and numerical modeling of geological and environmental processes are also expected.
Finally, we stress that the inter-disciplinary studies that highlight the multiscale properties of natural processes analyzed and monitored by using several methodologies are welcome.

Soil conservation is a necessary action to achieve a sustainable world because of the crucial role that soils play in the earth system. Reproducible and precise methods are vital to obtain credible data in the soil studies. This session will provide the premier forum for the presentation of new advances in the fields of experimental, theoretical, and applied soil conservation and eco sustainability. The topics of interest for submission may focus on the new technologies regarding soil conservation and eco sustainability together with the important results related to the novel approaches. In details, we seek abstracts on the following topics: erosional and depositional processes, watershed management, soil evolution and weathering, soils and surface processes, land degradation and restoration, environmental sustainability, resource management, sustainable cities, hazardous substances and detection techniques. The promoted methodologies include remote sensing, lab experiments, field experiments, environmental regulation and monitoring, economic technology and instruments, and modeling and decision support tools.

Methods of analysis used in the investigation of soil chemical, biochemical and physical properties play very important role in the progress of soil science. The accuracy of provided analyses and quality of new knowledge and discoveries depends directly from the choice of analytical methods. The wise usage of a wide range of different analytical methods and techniques serves as a foundation for the investigation of the processes in soils and for the assessment of the soil environmental status. Unfortunately, the importance of their utilisation often remains in the shadow and is principally underestimated. Today we can notice, that the spectrum of methods used in soil science varies starting from quite simple ones and ending with high-precision methods based on high-tech instruments.
The aim of this session is to present the usage of different laboratory methods and techniques in soil research and give the possibility for researchers to exchange their experiences. The special goal of this session is to promote a wider use of innovative analytical methods for determination of chemical compounds in mineral and organic soils, sediments, substrates and composts. The innovative methods covering soil organic matter and humic substances analysis are acknowledged. The new concept “lab on phone” has appeared in scientific literature during the last few years, which specifies the use of smartphones as analytical instruments in labs and also for field experiments.
The session gives a favourable opportunity to present the works describing the usage of ICP-MS, GC-MS, HPLC-MS, TGA-MS, FTIR, fluorescence etc. in the soil analysis . The session is not limited to these techniques or methods, the works describing the methods „lab on phone“ or any other innovative method or its application for soil analysis are very expected. The studies connected with methodology of soil chemical analysis and particularly soil organic matter and humic substances are awaited.

Well-designed experiments, measurement and modelling approaches are crucial methodologies in Soil Science, Geomorphology and Hydrology.

Depending on the specific research topic, a great variety of tempo-spatial scales is addressed. From raindrop impact and dust emission on field scale to the shaping of landscapes.

This virtual PICO-Session presents experiments, measurements and modelling approaches in the laboratory and the field investigating processes and quantities of soil detachment by wind, splash erosion and subsurface particle transport highlighting the role of vegetation, land use and harmonisation of experiments.

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. In the second part of this short course, hands-on for X-ray image analyses is offered.

Recent advances in image collection, e.g. using uncrewed 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 landscape scale.

For both historic and contemporary scenarios, the rise of techniques with ‘structure from motion’ (SfM) processing has democratized data access 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 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) modelling technologies, and iv) data processing tools, for instance, using machine learning approaches.

The session is addressed to experimentalists and modellers working on land surface interactions from local to regional scales. The programme is open to a wide range of new studies in micrometeorology and related atmospheric and remote sensing disciplines. The topics include the development of new devices, measurement techniques, experimental design, data analysis methods, as well as novel findings on surface layer theory and parametrization, including local and non-local processes. The theoretical parts encompass soil-vegetation-atmosphere transport, internal boundary-layer theories and flux footprint analyses. Of special interest are synergistic studies employing experimental data, parametrizations and models. This includes energy and trace gas fluxes (inert and reactive) as well as water, carbon dioxide and other GHG fluxes. Specific focus is given to outstanding problems in land surface boundary layer descriptions such as complex terrain, effects of horizontal heterogeneity on sub-meso-scale transport processes, energy balance closure, stable stratification and night time fluxes, dynamic interactions with atmosphere, plants (in canopy and above canopy) and soils.

Stable isotopes are powerful tools for tracing fluxes of water and associated nutrients in the soil-plant-atmosphere continuum. They are increasingly used by various disciplines to better understand the functioning of the soil-plant-atmosphere system. While new methods allow measurements at high spatial and temporal resolution, studies applying tracer methods are now tackling complex interactions between soil processes, plant physiology and ecology, and variable atmospheric drivers. As such, methodological developments and changes are happening quickly and have a strong bearing on process understanding and interpretation of findings. This session aims to address the current state of the art for methods, applications, and process interpretations using stable isotopes in the critical zone and to foster interdisciplinary exchange. We welcome experimental and modeling studies that present methodological developments and applications of isotope tracers to improve the actual knowledge of the water and nutrient exchanges at the soil-plant-atmosphere interfaces. Studies that seek to cross disciplinary boundaries and reveal new eco-hydrological process understanding are especially welcome.

The weathering of primary minerals, the formation of secondary minerals, and the build-up of larger composites up to the size of microaggregates influence the distribution and cycling of elements, nutrients and pollutants, with corresponding effects also on the Earth’s climate. Weathering and mineral formation in soils and sediments are strongly coupled to hydrological and biological processes. The understanding of soil structure formation at various environmental conditions remains rather obscure. Similarly, the understanding of the mechanisms of mineral weathering and composite structure formation on different spatial and temporal scales, their dependence on, and feedbacks with climate and biota, and their role for (trace) element speciation, mobility, and bioavailability is still rudimentary. Yet, aggregation is presumed mandatory to functionally link the "architecture" of soils to fluid flow and reactive transport, activity of microorganisms, the biogeochemical turnover of elements, the stability and resilience of soil structure, and functional and structural biodiversity. By employing field, laboratory, and modeling studies, we aim to compile and discuss recent advances. We will shed light on experimental and observational evidence and emerging concepts on the biogeochemical weathering and formation secondary minerals and larger composites up to the size of microaggregates on the fate of major (e.g., carbon, nitrogen, phosphorus, and sulfur) and trace elements (e.g., antimony, cadmium, molybdenum, and selenium).

The critical zone comprises the Earth's permeable near-surface layer from the top of the canopy to the bottom of the groundwater. It is the zone where hydrosphere, atmosphere, pedosphere and geosphere interact with the biosphere. This fragile skin of our planet, which supports the life and survival of humans maintaining food production and drinking water quality, is endangered by threats such as climate change and land use change.
New approaches and innovative modeling strategies are needed to understand these complex interactions between hydrological, biogeochemical cycles and human resilience processes that may govern critical zone system dynamics, including sources, dynamics and chemistry of water, models to quantify external influences like human activities or erosion, weathering rate, water transfer in the frame of global change and biolological feedback mechanisms.

This session focuses on the advancing proxies that may address pressing interdisciplinary scientific questions in coupling various disciplines like hydrology, soil science and biogeochemistry that cover single-site investigations, targeted experiments, remote sensing studies, large data compilations and modelling. This will be illustrated in this session through studies regarding the critical zone as a whole or within its different compartments, including the different environmental processes (geological, physical, chemical, and biological), their couplings and reactive transport modeling, and exploring the cities resilience.

One of the most challenging sustainable goals of the UN 2030 Agenda and other international agreements is that urban systems have to increase well-being and health. Indeed, these networked systems already host more than half of the world's population and are going to host most of its growth, while they have been mostly designed and managed with limited visions, in particular with respect to their geophysical environment.
This goal got an unforeseen acuity with the Covid-19 pandemic, starting with the confinement strategies that radically brought into question the functioning of these systems, e.g., drastically reducing mobility and breaking its ever increasing trend. Covid-19 was not without precursor (e.g., SARS, MERS) and will not be without successors.

Long term visions based on transdisciplinary scientific advances are therefore indispensable, particularly from the geoscience community. As a consequence, this session calls for contributions from data-driven and theory-driven approaches of urban health under global change. This includes:
- qualitative improvements of epidemic modelling, as trans-disciplinary and nonlinear as possible
- possible interplays between meteorological and/or climate drivers and epidemic/health issues
- novel monitoring capabilities (including contacts tracking), data access, assimilation and multidimensional analysis techniques
- managing field works, geophysical monitoring and planetary missions
- how to have the highest science output during corona pandemic
- a fundamental revision of our urban systems, their greening as well as their mobility offer
- a particular focus on urban biodiversity, in particular to better manage virus vectors
- urban resilience must include resilience to epidemics, and therefore requires revisions of urban governance.

Nature-based Solutions (NBS) are reframing discussion and policy responses worldwide to environmental challenges. Thus, NBS is of growing implementation, supported namely by the EU political agenda (e.g., green deal), as a way to attain the United Nations (UN) Sustainable Development Goals (SDG), and to reinforce the New Urban Agenda. The NBS concept recognise the importance of nature and outline requirements for a systemic and holistic approach to environmental change, based on an understanding of the structure and functioning of ecosystems, and the social and institutional context within which they are situated. Furthermore, there is a growing recognition that human activities exert pressure on natural resources affecting the ecosystem dynamics and therefore the nexus (synergies and trade-offs) between their different functions and services. However, quantification of existing NBS’ effectiveness, their operationalisation and replication in different environmental settings has not been presented in such a way that allows them to be both widely accepted and incorporated in policy development and in practical implementation to achieve the UN SDGs.
This session aims to discuss and advance knowledge of innovative NBS approaches to face environmental challenges, such as water supply and management, agricultural production and healthy ecosystems, and simultaneously provide better understanding of associated social-ecological interactions, contributing to enhance the scientific basis for sustainable development and resilience.
This session seeks to:
- Better understanding of advantages and disadvantages of NBS to address global environmental and societal challenges;
- Studies on adaptation and mitigation options for the effect of climate change on water provisioning and livelihoods;
- New methods and tools to investigate the role of NBS in the context of environmental change; in particular, the effectiveness of NBS for hydro-meteorological risk reduction at landscape/watershed scale;
- New insights, methodologies, tools and best practices enabling successful implementation and upscaling of NBS in multiple contexts;
- Identifying opportunities for and barriers to NBS within current regulatory frameworks and management practices;
- Presenting overviews and case studies of NBS projects that also involve the private sector and market-based mechanisms;
- NBS towards achieving the Sustainable Development Goals (SDGs).

Plastic contamination is a global concern. With increasing usage and disposal of plastics, waste management is often inefficient in processing the volumes of plastic discarded. A large proportion of plastic waste accumulates in the natural environment where clean-up is difficult, if not impossible. This results in the plastic contamination persisting in the environment for many years, having the potential to cause long-term ecological harm, ultimately affecting humans.

To mitigate plastic pollution and find solutions to reduce harmful effects, a better understanding of the sources and pathways of plastics in the environment is needed. This should inform social and industrial practices, as well as advise on regulatory changes to address plastic management. This will also promote developing a roadmap towards the development and safe usage of alternative materials, to reduce environmental and health implications. The approach aims at bringing together academics from a variety of research fields and citizen science initiatives along with stakeholders from civil society and industry, as well as regulators and policymakers. The task requires collaboration across disciplines, from environmental sciences, including biology and chemistry, geosciences, atmospheric sciences and oceanography, to materials science, social sciences and economics.

This session will address the linkages and cross-disciplinary collaborations required for effective progress in this field. We specifically invite presentations featuring successes and challenges in collaboration between academia, industry and regulators. Presentations on tracking plastics and on elucidating connecting mechanisms from human activities through to environmental abundance and impact are encouraged. Studies on biota-plastic interactions, plastic fluxes linked to human activities and environmental changes (from synoptic events to climate change) and studies linking plastic characteristics to toxicological impacts (chemistry, materials science and ecotoxicology) are welcomed.

This is a linked session co-organised and co-designed with a session at the annual meeting of SETAC Europe (Society of Environmental Toxicology and Chemistry), by connected convenor teams, to ensure full integration and input across disciplines. Outputs from the linked sessions will be disseminated widely across SETAC and EGU members through online resources, with a view to effective knowledge sharing and building collaborations.