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The contentious nature of soil organic matter

Nature volume 528, pages 6068 (03 December 2015) | Download Citation

Abstract

The exchange of nutrients, energy and carbon between soil organic matter, the soil environment, aquatic systems and the atmosphere is important for agricultural productivity, water quality and climate. Long-standing theory suggests that soil organic matter is composed of inherently stable and chemically unique compounds. Here we argue that the available evidence does not support the formation of large-molecular-size and persistent ‘humic substances’ in soils. Instead, soil organic matter is a continuum of progressively decomposing organic compounds. We discuss implications of this view of the nature of soil organic matter for aquatic health, soil carbon–climate interactions and land management.

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Author notes

    • Johannes Lehmann
    •  & Markus Kleber

    These authors contributed equally to this work.

Affiliations

  1. Soil and Crop Sciences, School of Integrated Plant Sciences, College of Agriculture and Life Sciences, Cornell University, Ithaca, New York, USA

    • Johannes Lehmann
  2. Atkinson Center for a Sustainable Future, Cornell University, Ithaca, New York, USA

    • Johannes Lehmann
  3. Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon, USA

    • Markus Kleber
  4. Institut für Bodenlandschaftsforschung, Leibniz Zentrum für Agrarlandschaftsforschung (ZALF), Müncheberg, Germany

    • Markus Kleber

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Both authors contributed equally to the concept, outline, and writing of the manuscript.

Competing interests

The authors declare no competing financial interests.

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Correspondence to Johannes Lehmann.

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https://doi.org/10.1038/nature16069

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