Soil is a heterogeneous and structured environment that is characterised by variable geometry, composition and stability, across spatial scales spanning several orders of magnitude. The physical structure of solid and pore space results in a complex distribution of oxygen, water films and gradients of solutes spanning distances as small as a few micrometers, all of which have a profound effect on the ecological and hydrological functioning of soil.
The soil structure is determined by an interplay of physical, chemical and biological mechanisms, the quantitative role of which is still poorly understood. Soil structure is difficult to study as it is a 3D opaque matrix. To shed light into soil structure, the concept of aggregate has often been used and defines “pieces” of soil structure, that remain bounded under disrupting forces. Microaggregates (250µm) are larger soil units, composed by microaggregates and primary particles, bound together by biological agents, such as roots, fungal hyphae or even earthworm activity. Cutting edge imaging techniques are as well used to observe “in situ” associations of mineral and organic material at micro- and macro-scales and the resulting ever changing pore space, which is partly destroyed when focusing on aggregates, even though it has a fundamental role in soil ecology and functioning.

In this session we integrate the description of structure and its dynamics, using new imaging techniques, with the ecological, functional and physical consequences of the spatial arrangement of soil constituents. A strong interdisciplinary approach is thus required, merging soil physicists, chemists and ecologists. The ultimate aim is to understand how soil structure, from micro-architecture to macropores, emerges from interactions within soil and how it determines the outcome of soil processes, in order to create models of soil functioning that integrate structure dynamics.
This session is divided into two oral blocks, one focusing more on the micro-scale in relation to microbial activities and the other accounting for micro- and macro-scale in relation to soil ecology of larger organisms and soil functioning. Carsten Mueller is the solicited speaker of the first oral block and Matthias Rillig is solicited for the second oral block.

Co-organized as HS8.3.10
Convener: Ulrich Weller | Co-conveners: Amandine Erktan, Naoise Nunan, Claire Chenu, Kai Uwe Totsche
| Wed, 10 Apr, 14:00–18:00
Room G1
| Attendance Thu, 11 Apr, 08:30–10:15
Hall X1

Wednesday, 10 April 2019 | Room G1

Chairperson: Naoise Nunan, Kai Uwe Totsche
14:00–14:15 |
| solicited
Carsten W. Mueller
14:15–14:30 |
Nadja Ray, Andreas Rupp, Alexander Prechtel, and Kai-Uwe Totsche
14:30–14:45 |
Ellen Kandeler, Aurelia Gebala, Runa S. Boeddinghaus, Karolin Müller, Thilo Rennert, Margarida Soares, Johannes Rousk, and Sven Marhan
14:45–15:00 |
Stefan Dultz, Susanne K. Woche, Robert Mikutta, and Georg Guggenberger
15:00–15:15 |
Carlos Gustavo Arellano Caicedo, Pelle Ohlsson, and Edith Hammer
15:15–15:30 |
Eva Lehndorff, Andrei Rodionov, Ciprian Stremtan, Willi Brand, Lutz Plümer, Peter Rottmann, Beate Spiering, and Wulf Amelung
15:30–15:45 |
Steffen A. Schweizer, Franziska B. Bucka, Markus Graf-Rosenfellner, and Ingrid Kögel-Knabner
Coffee break
Chairperson: Amandine Erktan, Ulrich Weller
16:15–16:30 |
| solicited
Matthias C. Rillig
16:30–16:45 |
Maik Lucas, Steffen Schlüter, Hans-Jörg Vogel, and Doris Vetterlein
17:00–17:15 |
Tobias L. Hohenbrink, Anne-Kathrin Schneider, Anne Zangerlé, Boris Schröder, and Loes van Schaik
17:15–17:30 |
Mark Hodson, Jamal Hallam, Joseph Holden, David Robinson, Jonathan Leake, Miranda Prendergast-Miller, Despina Berdeni, Martin Lappage, Emily Guest, Richard Grayson, and Anthony Turner
17:30–17:45 |
Sougueh Cheik Sougueh, Nicolas Bottinelli, Tran Minh Tien, and Pascal Jouquet
17:45–18:00 |
Sara König, Hans-Jörg Vogel, and Ulrich Weller