EUROSOIL 2012

S7.1.

Title: Soil organic matter at a molecular scale
Convener: Wiesenberg Guido - University of Bayreuth - Germany
Co-Conveners: Gonzalez-Perez Jose A. - IRNAS-CSIC - Spain        
Gonzalez-Vila Francisco J. - IRNAS-CSIC - Spain

During the last decades soil organic matter has been sophistically investigated at a molecular level resulting in an improved knowledge of processes taking place in soil organic matter stabilization. This sessions welcomes all contributions investigating soil organic matter at a molecular scale.

S7.2.

Title: Innovation and soil science - application of advanced NMR and MRI techniques for improving our understanding of soil organic matter formation and its interaction with the mineral phase
Convener: Knicker Heike - IRNAS-CSIC - Spain
Co-Conveners: Berns Anne - Forschungszentrum Jülich - Germany
Conte Pellegrino - University of Palermo - Italy

During the last years, NMR spectroscopy and MRI received considerable attention as means for studying the fate of organic matter in soils. Formerly considered as highly innovative, it turned into a tool that nowadays is established and routinely applied in many soil science laboratories. The ongoing demand for improved tools for studying biomolecules and pharmaceuticals, tremendously enhanced the development of specialized and advanced techniques in the field of one and two dimensional NMR and MRI as well as of relaxometry. The application of those techniques to the heterogeneous mixture "soil" certainly encounters problems concerning spectral resolution and sensitivity, and specific effort is required to adapt those analytical tools to the requirements of soil analysis. Therefore, the goal of the present session is to offer a platform, in which advanced NMR-based techniques are introduced and their applicability to research topics in soil science is discussed. With this attempt we intend to support the establishment of  promising techniques that have already been successfully applied in (bio)chemistry, material science or pharmaceutical research and to demonstrate that such advanced and sophisticated approaches can also contribute to our understanding of both biochemical and abiotic processes involved in soil organic matter formation, retention and stabilization. 

S7.3.

Title: Molecular methods for the characterization of organic matter in soils and for the appraisal of soil fertility and soil sequestration capacity
Convener: Piccolo Alessandro - University of Napoli Federico II - Italy
Co-Conveners: Spaccini Riccardo - University of Napoli Federico II - Italy
Spiteller Michael - University of Dortmund - Germany

The modern understanding of humus chemistry has shown that soil organic matter (SOM) is constituted by several thousands of different molecules associated in superstructures which are stabilized by hydrophobic and hydrogen bonds. While the humic heterogeneous molecules are the end product of the biodegradation process of plant litters and debris, belowground plant exudation, and synthesis of microbial metabolites, their chemical structure as well as their bioactivity are still a function of the specific physical soil properties and vegetation or crop grown on the soil.This recognition of the nature of SOM calls for a molecular approach in soil studies aimed to understand the biological mechanisms of SOM properties. The present availability of advanced physical-chemical instrumentation, as well as sophisticated chemical technologies for molecular recognition through catalytic and bioconjugating techniques, should be applied to enhance the basic hardness of Soil Science. New and advanced molecular approaches should be look for to characterize soil organic molecules in detail and contribute to a further understanding of the OM role in ecosystems and crop productions. In particular, useful and reproducible molecular biomarkers should be found to reveal the processes of SOM transformation and stabilization, highlight the impact of rhyzosphere on soil biofertility, and assess the SOM capacity to fix organic molecules and act as a sink of carbon. 

S7.4.

Title: Molecular dynamics of soil organic matter: challenges, opportunities and limits
Convener: Jansen Boris - University of Amsterdam - Netherlands
Co-Convener: Kögel-Knabner Ingrid - Technische Universitaet Muenchen - Germany

Stability, mobility and composition of soil organic matter (SOM) in various environments play a crucial role in issues ranging from agricultural production and the role of soils in the global carbon cycle, to pedogenesis and the reconstruction of past environments. Stability, mobility and composition of SOM in turn are largely governed by the interplay between its molecular properties and its biogeochemical interactions in a certain soil environment. In this session we try to bring together experts from different fields of SOM research in its broadest sense, but focusing on the molecular composition of SOM and changes thereof. Examples include:
-Transformation, preservation and sequestration of SOM or certain fractions thereof
-The effects of spatial heterogeneity in the soil environment on biogeochemical transformations (e.g. topsoil vs. subsoil)
-The effect of changes in climate and (historic) land use on molecular characteristics of SOM
-Sources of SOM dynamics (plant part/species specific input, rhizodeposition, microorganisms)
-The use of molecular methods to link organic matter dynamics in soils and waters
-The role of biogeochemical transformations of SOM in pedogenesis.
We also welcome researchers who focus on developing advanced molecular characterization and/or modeling techniques applicable to SOM research. Support for our session will be sought from MOLTER. 

S7.5.

Title: Soil organic matter dynamic and climate
Convener: Muscolo Adele Maria - Mediterranea University - Italy
Co-Conveners: Pavlovic Pavle - University of Belgrade - Serbia
Sidari Maria - Mediterranea University - Italy

The relationship  between SOM dynamics and climate change is widely recognized. The large Carbon stock in the soils could be an important factors in the feedback of SOM dynamics to climate change. Therefore this session will focus on experimental research aiming at unravelling the biotic and abiotic factors driving  SOM dynamic.   Special attention will be paid to research aiming at factors determining the chemical quality of SOM  and the availability of SOM to decomposers. Another point of focus will be the response of microbial metabolism to temperature changes and functional links between carbon turnover and microbial diversity in soils.

S7.6.

Title: Dynamics of subsoil organic carbon in relation to soil properties, climate and biota
Convener: Braakhekke Maarten - Max Planck Institute for Biogeochemistry - Germany
Co-Conveners: Hoosbeek Marcel - Wageningen University - Netherlands
Sierra Carlos - Max Planck Institute for Biogeochemistry - Germany

Despite the low soil organic carbon (OC) concentrations, subsoil OC can account for more than 50% of total soil OC. This makes subsoil OC an important carbon pool in the global carbon cycle and a potential sink or source of atmospheric carbon. A better understanding of the various processes and controls of subsoil OC stabilization and transport will help to advance current models on the dynamics of soil OC, leading to better estimates and an overall better understanding of the global carbon cycle. 
We aim to bring together scientists from three different, but related, branches of soil science: those that study soil OC pools, those that study soil OC fluxes, and those that try to model these pools and fluxes at various spatio-temporal scales. Studies that consider the effects of different soil properties, vegetation type, or climate on subsoil carbon dynamics are of particular interest.
We invite submissions from studies that focus on delineating the relative contribution of the various sources of subsoil organic carbon (i.e. rhizodeposition, DOC, bioturbation). Similarly, studies that attempt to infer subsurface fluxes and OC transport from CO2 concentration profile and surface flux measurements are welcome. Finally, we also invite contributions from researchers who develop models at various temporal and spatial scales and include subsoil organic carbon processes. 

S7.7.

Title: Mechanisms of C stabilization and sequestration in soils
Convener: Plaza César - CSIC - Spain
Co-Conveners: Marzadori Claudio - University of Bologna - Italy
Tejada Manuel - University of Seville - Spain
Zaccone Claudio - University of Foggia - Italy

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 (approximately twice as large as the total C in the atmosphere), which can have significant impacts on atmospheric CO2 concentrations and thereby on the 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 (e.g., humic substances and black C), occlusion by macro and microaggregation, and chemical interaction with soil mineral particles and metal ions. 

S7.8.

Title: Long-term effects of agronomic practices on soil organic carbon and crop productivity
Convener: Ventrella Domenico - CRA - Italy
Co-Convener: Francaviglia Rosa - CRA - Italy

Long term experiments play a fundamental role in understanding the evolution of soil fertility resulting from changes in agronomical practices. The maintenance or the improvement of soil organic carbon (SOC) in the soils has been the subject of many studies. For this subject, the current knowledge on how to effectively combine SOC maintenance or improvement with agricultural productivity is not solved. More specifically, the long-term impacts of agronomical practices on soil quality can be determined only with long-term experiments in which  continuous treatments are carried out for many years, allowing long-term dynamics  of soil carbon to be realizedThe general focus of this session will be to increase our understanding of how properties and dynamics of SOC are affected by agronomic practices carried out in long-term experiments and how such soil dynamics help to sustain the crop productivity in terms of yield and quality. In this session, the long-term studies related to the effects of management of crop residues, fertilization, amendment, tillage and crop rotation on SOC maintenance or improvement and crop productivity are solicited. 

S7.9.

Title: Fire effects on soil organic matter
Convener: Wiesenberg Guido - University of Bayreuth - Germany
Co-Conveners: Eckmeier Eileen - University of Bonn - Germany
Gonzalez-Perez Jose A. - IRNAS-CSIC - Spain  
Gonzalez-Vila Francisco J. - IRNAS-CSIC - Spain

Frequently occurring wild fires especially (but not only) in the Mediterranean area lead to a sustainable change in the plant cover and result in significant changes of soil organic matter and its fertility. In the proposed session all associated investigations from soil physical changes after fires affecting soil organic matter towards direct effects are dicussed. In addition to field studies following fires, laboratory experiments investigating the effect of fires on plant litter and soil organic matter are welcome. 

W7.1.

Title: Assessing SOM reproduction in arable soils
Convener: Franko Uwe - Helmholtz Centre for Environmental Research (UFZ) - Germany
Co-Conveners: Brock Christopher - Justus-Liebig-Universität Giessen - Germany
Oberholzer Hansrudolf - Agroscope Reckenholz-Tänikon ART - Switzerland

Soil organic matter (SOM) is an important component of soils and essential for proper soil functioning. Agricultural management activities have a strong impact on SOM turnover and storage in soils. There are threats to SOM-contents coming from direct or indirect effects of climate change due to higher temperatures and shifts in precipitation regimes or adaptations of soil management practices. A proper SOM regime is the precondition for a sustainable land use. Farmers need solutions to easily check their regime of SOM reproduction in order to adapt their management accordingly. This requires the assessment of the actual organic matter input and the site specific decomposition intensity as well as the impact of management activities on SOM reproduction. This workshop aims at a scientific discussion of principles, algorithms and parameters of different methodologies to describe SOM reproduction, including the assessment of the OM quality, of the SOM storage under different site conditions and of the impact of different field management systems on SOM-turnover, considering different scales from field to landscape.  Practical experiences shall be gathered, identifying successful implementations and open questions for further research.