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REVIEW

Lessons from a landmark 1991 article on soil structure: distinct precedence of non-destructive assessment and benefits of fresh perspectives in soil research

Philippe C. Baveye https://orcid.org/0000-0002-8432-6141 A * , María Balseiro-Romero B , Nicolas Bottinelli https://orcid.org/0000-0003-4944-9696 C D , María Briones E , Yvan Capowiez F , Patricia Garnier G , Alexandra Kravchenko H , Wilfred Otten I , Valérie Pot G , Steffen Schlüter J and Hans-Jörg Vogel J
+ Author Affiliations
- Author Affiliations

A Saint Loup Research Institute, 7 rue des chênes, La Grande Romelière, Saint Loup Lamairé, 79600 France.

B Instituto de Recursos Naturales y Agrobiología de Sevilla (CSIC), Sevilla, Spain.

C Soils and Fertilizers Research Institute, Hanoi 11910, Vietnam.

D IRD and CNRS, Institute of Ecology and Environmental Sciences Paris, 75005 Paris, France.

E Departamento de Ecología y Biología Animal, Universidade de Vigo, Vigo, Spain.

F INRAE, UMR 1114 EMMAH, INRAE – Université d’Avignon, Domaine Saint Paul, 84914 cedex 09, Avignon, France.

G UMR ECOSYS, INRAE, Université Paris-Saclay, Avenue Lucien Brétignières, Thiverval-Grignon, 78850 France.

H Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA.

I School of Water, Energy and Environment Building 52a, Cranfield University, Cranfield, Bedfordshire MK43 0AL, England.

J Helmholtz Centre for Environmental Research – UFZ, Permoserstr. 15, 04318 Leipzig, Germany.

* Correspondence to: Baveye.RPI@gmail.com

Handling Editor: Balwant Singh

Soil Research 60(4) 321-336 https://doi.org/10.1071/SR21268
Submitted: 25 October 2021  Accepted: 22 December 2021   Published: 19 January 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

In 1991, at the launch of a national symposium devoted to soil structure, the Australian Society of Soil Science invited Professor John Letey to deliver a keynote address, which was later published in the society’s journal. In his lecture, he shared the outcome of his reflexion about what the assessment of soil structure should amount to, in order to produce useful insight into the functioning of soils. His viewpoint was that the focus should be put on the openings present in the structure, rather than on the chunks of material resulting from its mechanical dismantlement. In the present article, we provide some historical background for Letey’s analysis, and try to explain why it took a number of years for the paradigm shift that he advocated to begin to occur. Over the last decade, his perspective that soil structure needs to be characterised via non-destructive methods appears to have gained significant momentum, which is likely to increase further in the near future, as we take advantage of recent technological advances. Other valuable lessons that one can derive from Letey’s pioneering article relate to the extreme value for everyone, even neophytes, to constantly ask questions about where research on given topics is heading, what its goals are, and whether the methods that are used at a certain time are optimal.

Keywords: aggregate stability, computed tomography, earthworms, micromorphology, soil fauna, soil functions, soil image analysis, soil microorganisms, soil measuring, soil organic matter.


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